Add debug hologram projector (#79)

StructureLib built the missing block name on the server, where only
en_US is loaded, so players on dedicated servers saw English names in
chat. Send the item's lang key and let the client translate it. Stacks
whose name is not a plain key, GT meta items among them, keep the old
server side name.

Players also saw two shapes of the same message: a bracketed name with
rarity color and an item tooltip from two of the survivalPlaceBlocks
branches, a bare yellow name from the stack list branch. All three now
build the name the same way.

.github/workflows/optimize-images.yml

@@ -0,0 +1,17 @@
+name: Optimize images
+
+on:
+  pull_request:
+    branches: [ master, main, release/** ]
+    paths:
+      - "**/*.png"
+
+  push:
+    branches: [ master, main, release/** ]
+    paths:
+      - "**/*.png"
+
+jobs:
+  optimize-images:
+    uses: GTNewHorizons/GTNH-Actions-Workflows/.github/workflows/optimize-images.yml@master
+    secrets: inherit

.github/workflows/publish-javadoc.yaml

@@ -5,6 +5,7 @@ on:
     branches:
       - master
       - feature/doc
+      - '**/*-javadoc'
     tags:
       - '*'
   delete:
@@ -26,7 +27,7 @@ jobs:
         with:
           fetch-depth: 0
           ref: gh-pages
-    
+
       - name: Deploy 🚀
         id: deploy
         shell: bash
@@ -34,17 +35,17 @@ jobs:
           if git rm -r $TARGET_FOLDER ; then
             echo Nothing to clean up
           fi
-          
+
           find . -name javadoc -type d -print | sed 's#^\./\(.*\)/javadoc$#\1#' | sort --version-sort --reverse > index.txt
           git add index.txt
           git config user.name "${GITHUB_ACTOR}"
           git config user.email "${GITHUB_ACTOR_ID}-${GITHUB_ACTOR}@users.noreply.github.com"
           git commit -m "Clean up javadoc after ref $TARGET_FOLDER is deleted"
           git push
-          echo "hash=$(git rev-parse HEAD)" >> $GITHUB_OUTPUT            
+          echo "hash=$(git rev-parse HEAD)" >> $GITHUB_OUTPUT
         env:
           TARGET_FOLDER: ${{ github.ref_name }}
-          
+
   javadoc:
     if: github.event_name == 'push'
     concurrency: javadoc-publish

LICENSE

@@ -0,0 +1,674 @@
+                    GNU GENERAL PUBLIC LICENSE
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+License would be to refrain entirely from conveying the Program.
+
+  13. Use with the GNU Affero General Public License.
+
+  Notwithstanding any other provision of this License, you have
+permission to link or combine any covered work with a work licensed
+under version 3 of the GNU Affero General Public License into a single
+combined work, and to convey the resulting work.  The terms of this
+License will continue to apply to the part which is the covered work,
+but the special requirements of the GNU Affero General Public License,
+section 13, concerning interaction through a network will apply to the
+combination as such.
+
+  14. Revised Versions of this License.
+
+  The Free Software Foundation may publish revised and/or new versions of
+the GNU General Public License from time to time.  Such new versions will
+be similar in spirit to the present version, but may differ in detail to
+address new problems or concerns.
+
+  Each version is given a distinguishing version number.  If the
+Program specifies that a certain numbered version of the GNU General
+Public License "or any later version" applies to it, you have the
+option of following the terms and conditions either of that numbered
+version or of any later version published by the Free Software
+Foundation.  If the Program does not specify a version number of the
+GNU General Public License, you may choose any version ever published
+by the Free Software Foundation.
+
+  If the Program specifies that a proxy can decide which future
+versions of the GNU General Public License can be used, that proxy's
+public statement of acceptance of a version permanently authorizes you
+to choose that version for the Program.
+
+  Later license versions may give you additional or different
+permissions.  However, no additional obligations are imposed on any
+author or copyright holder as a result of your choosing to follow a
+later version.
+
+  15. Disclaimer of Warranty.
+
+  THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
+APPLICABLE LAW.  EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT
+HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY
+OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO,
+THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+PURPOSE.  THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM
+IS WITH YOU.  SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF
+ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
+
+  16. Limitation of Liability.
+
+  IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
+WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
+THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
+GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
+USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
+DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
+PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
+EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
+SUCH DAMAGES.
+
+  17. Interpretation of Sections 15 and 16.
+
+  If the disclaimer of warranty and limitation of liability provided
+above cannot be given local legal effect according to their terms,
+reviewing courts shall apply local law that most closely approximates
+an absolute waiver of all civil liability in connection with the
+Program, unless a warranty or assumption of liability accompanies a
+copy of the Program in return for a fee.
+
+                     END OF TERMS AND CONDITIONS
+
+            How to Apply These Terms to Your New Programs
+
+  If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+  To do so, attach the following notices to the program.  It is safest
+to attach them to the start of each source file to most effectively
+state the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+    <one line to give the program's name and a brief idea of what it does.>
+    Copyright (C) <year>  <name of author>
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+Also add information on how to contact you by electronic and paper mail.
+
+  If the program does terminal interaction, make it output a short
+notice like this when it starts in an interactive mode:
+
+    <program>  Copyright (C) <year>  <name of author>
+    This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
+    This is free software, and you are welcome to redistribute it
+    under certain conditions; type `show c' for details.
+
+The hypothetical commands `show w' and `show c' should show the appropriate
+parts of the General Public License.  Of course, your program's commands
+might be different; for a GUI interface, you would use an "about box".
+
+  You should also get your employer (if you work as a programmer) or school,
+if any, to sign a "copyright disclaimer" for the program, if necessary.
+For more information on this, and how to apply and follow the GNU GPL, see
+<https://www.gnu.org/licenses/>.
+
+  The GNU General Public License does not permit incorporating your program
+into proprietary programs.  If your program is a subroutine library, you
+may consider it more useful to permit linking proprietary applications with
+the library.  If this is what you want to do, use the GNU Lesser General
+Public License instead of this License.  But first, please read
+<https://www.gnu.org/licenses/why-not-lgpl.html>.

addon.gradle

@@ -1,7 +1,7 @@
 javadoc {
     javadocTool = javaToolchains.javadocToolFor {
         // Last version with frames, but it also has search
-        languageVersion = JavaLanguageVersion.of(11)
+        languageVersion = JavaLanguageVersion.of(25)
         vendor = JvmVendorSpec.ADOPTIUM
     }
 
@@ -18,9 +18,8 @@ javadoc {
 
     options {
         overview "src/main/javadoc/overview.html"
-        links 'https://docs.oracle.com/javase/8/docs/api/'
+        links 'https://docs.oracle.com/en/java/javase/25/docs/api/'
         links 'https://skmedix.github.io/ForgeJavaDocs/javadoc/forge/1.7.10-10.13.4.1614/'
-        addBooleanOption("-frames", true)
     }
 }
 

dependencies.gradle

@@ -1,9 +1,9 @@
 // Add your dependencies here
 
 dependencies {
-    api("com.github.GTNewHorizons:GTNHLib:0.8.44:dev")
-    implementation("com.github.GTNewHorizons:NotEnoughItems:2.8.48-GTNH:dev")
-
+    api("com.github.GTNewHorizons:GTNHLib:0.11.21:dev")
+    implementation("com.github.GTNewHorizons:NotEnoughItems:2.8.110-GTNH:dev")
     testImplementation(platform('org.junit:junit-bom:5.9.2'))
     testImplementation('org.junit.jupiter:junit-jupiter')
+	testRuntimeOnly ('org.junit.platform:junit-platform-launcher')
 }

gradle.properties

@@ -39,14 +39,34 @@ remoteMappings = https\://raw.githubusercontent.com/MinecraftForge/FML/1.7.10/co
 # `./gradlew runClient --username=AnotherPlayer`, or configuring this command in your IDE.
 developmentEnvironmentUserName = Developer
 
-# Enables using modern Java syntax (up to version 17) via Jabel, while still targeting JVM 8.
-# See https://github.com/bsideup/jabel for details on how this works.
-enableModernJavaSyntax = true
+# Enables modern Java syntax support. Valid values:
+# - false: No modern syntax, Java 8 only
+# - jabel: Jabel syntax-only support, compiles to J8 bytecode
+# - jvmDowngrader: Full modern Java via JVM Downgrader (syntax + stdlib APIs)
+# - modern: Native modern Java bytecode, no downgrading
+enableModernJavaSyntax = jabel
 
 # If set, ignores the above setting and compiles with the given toolchain. This may cause unexpected issues,
 # and should *not* be used in most situations. -1 disables this.
 # forceToolchainVersion = -1
 
+# Target JVM version for JVM Downgrader bytecode downgrading.
+# Only used when enableModernJavaSyntax = jvmDowngrader
+# downgradeTargetVersion = 8
+
+# Comma-separated list of Java versions for multi-release jar support (JVM Downgrader only).
+# Classes will be available in META-INF/versions/N/ for each version N in this list.
+# Default: "21,25" (J25+ gets native classes, J21-24 gets partial downgrade, J8-20 gets full downgrade).
+# jvmDowngraderMultiReleaseVersions = 21,25
+
+# Specifies how JVM Downgrader API stubs are provided. Options:
+# - shade: Shade minimized stubs into the jar
+# - gtnhlib: GTNHLib provides stubs at runtime (adds version constraint)
+# - external: Another dependency provides stubs (no constraint, no warning)
+# - (empty): Warning reminding you to configure stubs
+# Note: 'shade' option requires you to verify license compliance, see: https://github.com/unimined/JvmDowngrader/blob/main/LICENSE.md
+# jvmDowngraderStubsProvider =
+
 # Enables injecting missing generics into the decompiled source code for a better coding experience.
 # Turns most publicly visible List, Map, etc. into proper List<E>, Map<K, V> types.
 enableGenericInjection = true

gradle/gradle-daemon-jvm.properties

@@ -1,12 +1,12 @@
 #This file is generated by updateDaemonJvm
-toolchainUrl.FREE_BSD.AARCH64=https\://api.foojay.io/disco/v3.0/ids/df211d3c3eefdc408b462041881bc575/redirect
-toolchainUrl.FREE_BSD.X86_64=https\://api.foojay.io/disco/v3.0/ids/b41931cf1e70bc8e08d7dd19c343ef00/redirect
-toolchainUrl.LINUX.AARCH64=https\://api.foojay.io/disco/v3.0/ids/df211d3c3eefdc408b462041881bc575/redirect
-toolchainUrl.LINUX.X86_64=https\://api.foojay.io/disco/v3.0/ids/b41931cf1e70bc8e08d7dd19c343ef00/redirect
-toolchainUrl.MAC_OS.AARCH64=https\://api.foojay.io/disco/v3.0/ids/46949723aaa20c7b64d7ecfed7207034/redirect
-toolchainUrl.MAC_OS.X86_64=https\://api.foojay.io/disco/v3.0/ids/d6690dfd71c4c91e08577437b5b2beb0/redirect
-toolchainUrl.UNIX.AARCH64=https\://api.foojay.io/disco/v3.0/ids/df211d3c3eefdc408b462041881bc575/redirect
-toolchainUrl.UNIX.X86_64=https\://api.foojay.io/disco/v3.0/ids/b41931cf1e70bc8e08d7dd19c343ef00/redirect
-toolchainUrl.WINDOWS.AARCH64=https\://api.foojay.io/disco/v3.0/ids/3cd7045fca9a72cd9bc7d14a385e594c/redirect
-toolchainUrl.WINDOWS.X86_64=https\://api.foojay.io/disco/v3.0/ids/552c7bffe0370c66410a51c55985b511/redirect
+toolchainUrl.FREE_BSD.AARCH64=https\://api.foojay.io/disco/v3.0/ids/cf726b4a1c84b50457225f9bba6d7650/redirect
+toolchainUrl.FREE_BSD.X86_64=https\://api.foojay.io/disco/v3.0/ids/fa1e318c287360478e3c83a9a3ef1007/redirect
+toolchainUrl.LINUX.AARCH64=https\://api.foojay.io/disco/v3.0/ids/cf726b4a1c84b50457225f9bba6d7650/redirect
+toolchainUrl.LINUX.X86_64=https\://api.foojay.io/disco/v3.0/ids/fa1e318c287360478e3c83a9a3ef1007/redirect
+toolchainUrl.MAC_OS.AARCH64=https\://api.foojay.io/disco/v3.0/ids/c2dd35c9d0aaf0ba6ad0791320f99dfc/redirect
+toolchainUrl.MAC_OS.X86_64=https\://api.foojay.io/disco/v3.0/ids/e5810bd7fd1f8a586644409d395a7e55/redirect
+toolchainUrl.UNIX.AARCH64=https\://api.foojay.io/disco/v3.0/ids/cf726b4a1c84b50457225f9bba6d7650/redirect
+toolchainUrl.UNIX.X86_64=https\://api.foojay.io/disco/v3.0/ids/fa1e318c287360478e3c83a9a3ef1007/redirect
+toolchainUrl.WINDOWS.AARCH64=https\://api.foojay.io/disco/v3.0/ids/7b3c4877c0749019e6805bb61e421497/redirect
+toolchainUrl.WINDOWS.X86_64=https\://api.foojay.io/disco/v3.0/ids/d76df094a9cbbabd3b08251f9e61444a/redirect
 toolchainVersion=25

gradle/wrapper/gradle-wrapper.properties

@@ -1,6 +1,6 @@
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-9.2.1-bin.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-9.4.0-bin.zip
 networkTimeout=10000
 validateDistributionUrl=true
 zipStoreBase=GRADLE_USER_HOME

gradlew

@@ -57,7 +57,7 @@
 #       Darwin, MinGW, and NonStop.
 #
 #   (3) This script is generated from the Groovy template
-#       https://github.com/gradle/gradle/blob/HEAD/platforms/jvm/plugins-application/src/main/resources/org/gradle/api/internal/plugins/unixStartScript.txt
+#       https://github.com/gradle/gradle/blob/b631911858264c0b6e4d6603d677ff5218766cee/platforms/jvm/plugins-application/src/main/resources/org/gradle/api/internal/plugins/unixStartScript.txt
 #       within the Gradle project.
 #
 #       You can find Gradle at https://github.com/gradle/gradle/.

settings.gradle

@@ -17,7 +17,7 @@ pluginManagement {
 }
 
 plugins {
-    id 'com.gtnewhorizons.gtnhsettingsconvention' version '2.0.10'
+    id 'com.gtnewhorizons.gtnhsettingsconvention' version '2.0.26'
 }
 
 

src/main/java/com/gtnewhorizon/structurelib/ChannelPickHandler.java

@@ -0,0 +1,88 @@
+package com.gtnewhorizon.structurelib;
+
+import java.util.Collection;
+import java.util.Map;
+
+import javax.annotation.Nullable;
+
+import net.minecraft.block.Block;
+import net.minecraft.entity.player.EntityPlayer;
+import net.minecraft.entity.player.EntityPlayerMP;
+import net.minecraft.item.ItemStack;
+import net.minecraft.util.ChatComponentTranslation;
+import net.minecraft.util.MovingObjectPosition;
+import net.minecraft.world.World;
+
+import com.gtnewhorizon.structurelib.alignment.constructable.ChannelDataAccessor;
+import com.gtnewhorizon.structurelib.net.SetChannelDataMessage;
+
+/**
+ * Handler for middle-click channel picking. When the player holds a hologram projector on the cursor and middle-clicks
+ * a registered indicator item, the corresponding channel is set on the projector. The same applies in world when the
+ * projector is held in hand and a registered indicator block is middle-clicked. Shift+middle-click wipes all channels.
+ * Was made side neutral to support server-side validation at some point if necessary.
+ */
+public final class ChannelPickHandler {
+
+    private ChannelPickHandler() {}
+
+    /**
+     * Handle a middle-click event while holding a hologram projector on the cursor.
+     */
+    public static boolean handleMiddleClick(EntityPlayer player, ItemStack holoStack, @Nullable ItemStack targetStack,
+            final boolean isSneaking) {
+        return handlePick(player, holoStack, targetStack, isSneaking, true);
+    }
+
+    public static boolean handleWorldPick(World world, EntityPlayer player, ItemStack holoStack,
+            @Nullable MovingObjectPosition hit, final boolean isSneaking) {
+        ItemStack targetStack = null;
+
+        if (hit != null) {
+            Block block = world.getBlock(hit.blockX, hit.blockY, hit.blockZ);
+            if (!block.isAir(world, hit.blockX, hit.blockY, hit.blockZ)) {
+                targetStack = block.getPickBlock(hit, world, hit.blockX, hit.blockY, hit.blockZ, player);
+            }
+        }
+
+        // A null target still goes through so that shift+middle-click wipes even when aiming at nothing
+        return handlePick(player, holoStack, targetStack, isSneaking, false);
+    }
+
+    private static boolean handlePick(EntityPlayer player, ItemStack holoStack, @Nullable ItemStack targetStack,
+            final boolean isSneaking, final boolean onCursor) {
+        // Clear channels on shift+middle-click. The "press again to confirm" gesture is gated client-side
+        // (see ChannelWipeConfirmation) before this method is ever called.
+        if (isSneaking) {
+            ChannelDataAccessor.wipeChannelData(holoStack);
+            sendChannelData(player, holoStack, onCursor);
+            player.addChatMessage(new ChatComponentTranslation("structurelib.pickchannel.cleared"));
+            return true;
+        }
+
+        if (targetStack == null) return false; // nothing hovered, cancel silently
+
+        Collection<Map.Entry<String, Integer>> channels = ChannelDescription.iterate(targetStack);
+        if (channels.isEmpty()) {
+            player.addChatMessage(new ChatComponentTranslation("structurelib.pickchannel.nomapping"));
+            return false;
+        }
+
+        // Assuming there's only 1 channel per item for now (same behavior as drag and drop)
+        Map.Entry<String, Integer> first = channels.iterator().next();
+        ChannelDataAccessor.setChannelData(holoStack, first.getKey(), first.getValue());
+        sendChannelData(player, holoStack, onCursor);
+        player.addChatMessage(
+                new ChatComponentTranslation("structurelib.pickchannel.success", first.getKey(), first.getValue()));
+        return true;
+    }
+
+    /**
+     * Player is the one triggering this update, so should already be in-sync.
+     */
+    private static void sendChannelData(EntityPlayer player, ItemStack holoStack, boolean onCursor) {
+        if (!(player instanceof EntityPlayerMP)) {
+            StructureLib.net.sendToServer(new SetChannelDataMessage(holoStack, onCursor));
+        }
+    }
+}

src/main/java/com/gtnewhorizon/structurelib/ChannelWipeConfirmation.java

@@ -0,0 +1,33 @@
+package com.gtnewhorizon.structurelib;
+
+import net.minecraft.client.Minecraft;
+import net.minecraft.entity.player.EntityPlayer;
+import net.minecraft.util.ChatComponentTranslation;
+
+/**
+ * Client-side-only confirmation gate for "wipe all channels" shift+middle-click gesture.
+ */
+public final class ChannelWipeConfirmation {
+
+    private static final long CONFIRM_WINDOW_MS = 5000;
+    private static long armedAtMs = -1;
+
+    private ChannelWipeConfirmation() {}
+
+    /**
+     * Call this before invoking {@link ChannelPickHandler} whenever the wipe gesture (shift+middle-click) is detected.
+     *
+     * @return true if this is a confirming second press within the window and the wipe should proceed now; false if
+     *         this press only armed the confirmation.
+     */
+    public static boolean confirm(EntityPlayer player) {
+        long now = Minecraft.getSystemTime();
+        if (now - armedAtMs > CONFIRM_WINDOW_MS) {
+            armedAtMs = now;
+            player.addChatMessage(new ChatComponentTranslation("structurelib.pickchannel.confirmwipe"));
+            return false;
+        }
+        armedAtMs = -1;
+        return true;
+    }
+}

src/main/java/com/gtnewhorizon/structurelib/ClientProxy.java

@@ -30,6 +30,7 @@ import net.minecraft.util.IChatComponent;
 import net.minecraft.util.IIcon;
 import net.minecraft.util.Vec3;
 import net.minecraft.world.World;
+import net.minecraftforge.client.event.MouseEvent;
 import net.minecraftforge.client.event.RenderWorldLastEvent;
 import net.minecraftforge.common.MinecraftForge;
 import net.minecraftforge.common.config.ConfigElement;
@@ -40,6 +41,7 @@ import org.apache.commons.lang3.tuple.Pair;
 import org.lwjgl.opengl.GL11;
 
 import com.gtnewhorizon.structurelib.entity.fx.WeightlessParticleFX;
+import com.gtnewhorizon.structurelib.item.ItemConstructableTrigger;
 import com.gtnewhorizon.structurelib.net.RegistryOrderSyncMessage;
 import com.gtnewhorizon.structurelib.net.SetChannelDataMessage;
 
@@ -53,6 +55,8 @@ import cpw.mods.fml.common.eventhandler.SubscribeEvent;
 import cpw.mods.fml.common.gameevent.TickEvent.ClientTickEvent;
 import cpw.mods.fml.common.gameevent.TickEvent.Phase;
 import cpw.mods.fml.common.network.FMLNetworkEvent;
+import cpw.mods.fml.relauncher.Side;
+import cpw.mods.fml.relauncher.SideOnly;
 
 public class ClientProxy extends CommonProxy {
 
@@ -346,9 +350,7 @@ public class ClientProxy extends CommonProxy {
         @Override
         public boolean equals(Object o) {
             if (this == o) return true;
-            if (!(o instanceof HintParticleInfo)) return false;
-
-            HintParticleInfo that = (HintParticleInfo) o;
+            if (!(o instanceof HintParticleInfo that)) return false;
 
             return x == that.x && y == that.y && z == that.z;
         }
@@ -397,8 +399,6 @@ public class ClientProxy extends CommonProxy {
             double worldY = y + 0.25;
             double worldZ = z + 0.25;
 
-            // this rendering code is independently written by glee8e on July 10th, 2023
-            // and is released as part of StructureLib under LGPL terms, just like everything else in this project
             // cube is a very special model. its facings can be rendered correctly by viewer distance without using
             // surface normals and view vector
             // here we do a 2 pass render.
@@ -564,6 +564,35 @@ public class ClientProxy extends CommonProxy {
 
     public static class ForgeEventHandler {
 
+        @SubscribeEvent
+        @SideOnly(Side.CLIENT)
+        public void onMouseEvent(MouseEvent event) {
+            final EntityPlayer player = Minecraft.getMinecraft().thePlayer;
+
+            if (player == null || player.isDead) {
+                return;
+            }
+
+            final ItemStack heldItem = player.getHeldItem();
+
+            if (heldItem == null || !(heldItem.getItem() instanceof ItemConstructableTrigger)) return;
+
+            if (event.button != 2 || !event.buttonstate) return;
+
+            // Sink the middle click as soon as a projector is held, so vanilla pick block does not run
+            event.setCanceled(true);
+
+            final boolean isSneaking = player.isSneaking();
+            if (isSneaking && !ChannelWipeConfirmation.confirm(player)) return;
+
+            ChannelPickHandler.handleWorldPick(
+                    player.worldObj,
+                    player,
+                    heldItem,
+                    Minecraft.getMinecraft().objectMouseOver,
+                    isSneaking);
+        }
+
         @SubscribeEvent
         public void onEntityJoinWorld(EntityJoinWorldEvent e) {
             if (e.world.isRemote && e.entity instanceof EntityClientPlayerMP) {

src/main/java/com/gtnewhorizon/structurelib/CommonProxy.java

@@ -17,6 +17,7 @@ import net.minecraftforge.common.MinecraftForge;
 import com.gtnewhorizon.structurelib.net.ErrorHintParticleMessage;
 import com.gtnewhorizon.structurelib.net.UpdateHintParticleMessage;
 
+import cpw.mods.fml.common.event.FMLInitializationEvent;
 import cpw.mods.fml.common.event.FMLLoadCompleteEvent;
 import cpw.mods.fml.common.event.FMLPreInitializationEvent;
 import cpw.mods.fml.common.eventhandler.SubscribeEvent;
@@ -64,6 +65,8 @@ public class CommonProxy {
 
     public void preInit(FMLPreInitializationEvent e) {}
 
+    public void init(FMLInitializationEvent e) {}
+
     public long getOverworldTime() {
         return MinecraftServer.getServer().getEntityWorld().getTotalWorldTime();
     }

src/main/java/com/gtnewhorizon/structurelib/GuiEditRegistryConfig.java

@@ -112,7 +112,6 @@ public class GuiEditRegistryConfig extends GuiScreen {
     /**
      * Adds the buttons (and other controls) to the screen in question.
      */
-    @SuppressWarnings("unchecked")
     @Override
     public void initGui() {
         Keyboard.enableRepeatEvents(true);
@@ -185,8 +184,7 @@ public class GuiEditRegistryConfig extends GuiScreen {
      */
     @Override
     public void onGuiClosed() {
-        if (this.configID != null && this.parentScreen instanceof GuiConfig) {
-            GuiConfig parentGuiConfig = (GuiConfig) this.parentScreen;
+        if (this.configID != null && this.parentScreen instanceof GuiConfig parentGuiConfig) {
             parentGuiConfig.needsRefresh = true;
             parentGuiConfig.initGui();
         }
@@ -319,21 +317,16 @@ public class GuiEditRegistryConfig extends GuiScreen {
         for (EntriesList list : lists) {
             list.drawScreenPost(mouseX, mouseY, partialTicks);
         }
-        if (this.undoHoverChecker.checkHover(mouseX, mouseY)) this.drawToolTip(
+        if (this.undoHoverChecker.checkHover(mouseX, mouseY)) this.func_146283_a(
                 this.mc.fontRenderer.listFormattedStringToWidth(I18n.format("fml.configgui.tooltip.undoAll"), 300),
                 mouseX,
                 mouseY);
-        if (this.resetHoverChecker.checkHover(mouseX, mouseY)) this.drawToolTip(
+        if (this.resetHoverChecker.checkHover(mouseX, mouseY)) this.func_146283_a(
                 this.mc.fontRenderer.listFormattedStringToWidth(I18n.format("fml.configgui.tooltip.resetAll"), 300),
                 mouseX,
                 mouseY);
     }
 
-    @SuppressWarnings("rawtypes")
-    public void drawToolTip(List stringList, int x, int y) {
-        this.func_146283_a(stringList, x, y);
-    }
-
     private class EntriesList extends GuiListExtended {
 
         final String heading;
@@ -571,13 +564,13 @@ public class GuiEditRegistryConfig extends GuiScreen {
         void drawToolTip(int mouseX, int mouseY) {
             // ensure checkHover() is always called, or the hover threshold might fail under certain corner cases
             if (hoverCheckerText.checkHover(mouseX, mouseY)) {
-                GuiEditRegistryConfig.this.drawToolTip(
+                GuiEditRegistryConfig.this.func_146283_a(
                         mc.fontRenderer.listFormattedStringToWidth(tooltip, entriesList.getListWidth()),
                         mouseX,
                         mouseY);
             }
             if (hoverCheckerBtnDrag.checkHover(mouseX, mouseY) && !isDragging) {
-                GuiEditRegistryConfig.this.drawToolTip(
+                GuiEditRegistryConfig.this.func_146283_a(
                         mc.fontRenderer.listFormattedStringToWidth(
                                 I18n.format("structurelib.configgui.drag.tooltip"),
                                 entriesList.getListWidth()),

src/main/java/com/gtnewhorizon/structurelib/SortedRegistry.java

@@ -75,7 +75,6 @@ public class SortedRegistry<V> implements Iterable<V> {
     }
 
     static void cleanup(MinecraftServer server) {
-        @SuppressWarnings("unchecked")
         List<EntityPlayerMP> players = server.getConfigurationManager().playerEntityList;
         Set<UUID> onlinePlayerIDs = players.stream().map(EntityPlayerMP::getUniqueID).collect(Collectors.toSet());
         int removed = 0;

src/main/java/com/gtnewhorizon/structurelib/StructureLib.java

@@ -22,6 +22,7 @@ import com.gtnewhorizon.structurelib.command.CommandConfigureChannels;
 import com.gtnewhorizon.structurelib.command.CommandRegistryDebug;
 import com.gtnewhorizon.structurelib.item.ItemBlockHint;
 import com.gtnewhorizon.structurelib.item.ItemConstructableTrigger;
+import com.gtnewhorizon.structurelib.item.ItemDebugConstructableTrigger;
 import com.gtnewhorizon.structurelib.item.ItemFrontRotationTool;
 import com.gtnewhorizon.structurelib.net.AlignmentMessage;
 import com.gtnewhorizon.structurelib.net.ErrorHintParticleMessage;
@@ -33,6 +34,7 @@ import com.gtnewhorizon.structurelib.util.XSTR;
 
 import cpw.mods.fml.common.Mod;
 import cpw.mods.fml.common.SidedProxy;
+import cpw.mods.fml.common.event.FMLInitializationEvent;
 import cpw.mods.fml.common.event.FMLInterModComms;
 import cpw.mods.fml.common.event.FMLLoadCompleteEvent;
 import cpw.mods.fml.common.event.FMLPreInitializationEvent;
@@ -98,6 +100,7 @@ public class StructureLib {
     static Item itemBlockHint;
     static Item itemFrontRotationTool;
     static Item itemConstructableTrigger;
+    static Item itemDebugConstructableTrigger;
     public static final CreativeTabs creativeTab = new CreativeTabs("structurelib") {
 
         @Override
@@ -118,6 +121,9 @@ public class StructureLib {
         GameRegistry.registerItem(
                 itemConstructableTrigger = new ItemConstructableTrigger(),
                 itemConstructableTrigger.getUnlocalizedName());
+        GameRegistry.registerItem(
+                itemDebugConstructableTrigger = new ItemDebugConstructableTrigger(),
+                itemDebugConstructableTrigger.getUnlocalizedName());
         proxy.preInit(e);
         NetworkRegistry.INSTANCE.registerGuiHandler(instance(), new GuiHandler());
 
@@ -128,6 +134,11 @@ public class StructureLib {
         DevelopHelper.onPreInit();
     }
 
+    @Mod.EventHandler
+    public void init(FMLInitializationEvent e) {
+        proxy.init(e);
+    }
+
     @Mod.EventHandler
     public void loadComplete(FMLLoadCompleteEvent e) {
         proxy.loadComplete(e);

src/main/java/com/gtnewhorizon/structurelib/alignment/constructable/ChannelDataAccessor.java

@@ -38,7 +38,9 @@ public class ChannelDataAccessor {
      * If given subchannel does not exist, masterStack may or may not be returned to save performance. Code within
      * StructureLib can depend on this behavior, you cannot.
      *
-     * @param masterStack trigger item. can be the return value of another {@link #withChannel(ItemStack, String)} call
+     * @param masterStack trigger item. can be the return value of another
+     *                    {@link com.gtnewhorizon.structurelib.alignment.constructable.ChannelDataAccessor#withChannel(net.minecraft.item.ItemStack, String)}
+     *                    call
      * @param channel     subchannel to use. will use current master channel data instead if this channel does not exist
      *                    Note: all channel identifiers are supposed to be lower case and not empty.
      * @return a trigger item with new master channel
@@ -107,13 +109,13 @@ public class ChannelDataAccessor {
      * 
      * @param masterStack trigger stack to check
      * @param channel     channel identifier. Note: all channel identifiers are supposed to be lower case and not empty.
-     * @param data        subchannel data. should always be a positive value
+     * @param data        positive subchannel data
      */
     public static void setChannelData(ItemStack masterStack, String channel, int data) {
         if (StringUtils.isEmpty(channel) || masterStack == null) throw new IllegalArgumentException();
+        if (data < 1) throw new IllegalArgumentException("Channel data must be positive");
         if (StructureLibAPI.isDebugEnabled() && !channel.toLowerCase(Locale.ROOT).equals(channel))
             throw new IllegalArgumentException("Channel name can be lower case ONLY");
-        if (data <= 0) throw new IllegalArgumentException();
         if (masterStack.stackTagCompound == null) masterStack.stackTagCompound = new NBTTagCompound();
         NBTTagCompound main = masterStack.stackTagCompound;
         if (!main.hasKey(SECONDARY_HINT_TAG, TAG_COMPOUND)) main.setTag(SECONDARY_HINT_TAG, new NBTTagCompound());
@@ -146,7 +148,12 @@ public class ChannelDataAccessor {
      */
     public static void wipeChannelData(ItemStack masterStack) {
         if (masterStack == null) throw new IllegalArgumentException();
-        if (masterStack.stackTagCompound != null) masterStack.stackTagCompound.removeTag(SECONDARY_HINT_TAG);
+        if (masterStack.stackTagCompound != null) {
+            masterStack.stackTagCompound.removeTag(SECONDARY_HINT_TAG);
+            if (masterStack.stackTagCompound.hasNoTags()) {
+                masterStack.stackTagCompound = null;
+            }
+        }
     }
 
     /**

src/main/java/com/gtnewhorizon/structurelib/alignment/constructable/ConstructableUtility.java

@@ -16,6 +16,7 @@ import com.gtnewhorizon.structurelib.StructureLib;
 import com.gtnewhorizon.structurelib.StructureLibAPI;
 import com.gtnewhorizon.structurelib.alignment.IAlignment;
 import com.gtnewhorizon.structurelib.alignment.enumerable.ExtendedFacing;
+import com.gtnewhorizon.structurelib.item.ItemDebugConstructableTrigger;
 import com.gtnewhorizon.structurelib.structure.IItemSource;
 import com.gtnewhorizon.structurelib.structure.ISurvivalBuildEnvironment;
 
@@ -70,11 +71,10 @@ public class ConstructableUtility {
 
         if (constructable == null) return false;
 
-        if (aPlayer instanceof EntityPlayerMP) {
-            EntityPlayerMP playerMP = (EntityPlayerMP) aPlayer;
+        if (aPlayer instanceof EntityPlayerMP playerMP) {
             // server side and sneaking (already checked above)
             // do construct
-            if (aPlayer.capabilities.isCreativeMode) {
+            if (aPlayer.capabilities.isCreativeMode || aStack.getItem() instanceof ItemDebugConstructableTrigger) {
                 constructable.construct(aStack, false);
             } else if (constructable instanceof ISurvivalConstructable) {
                 int built = ((ISurvivalConstructable) constructable).survivalConstruct(

src/main/java/com/gtnewhorizon/structurelib/block/BlockHint.java

@@ -65,10 +65,9 @@ public class BlockHint extends Block {
     }
 
     @Override
-    @SuppressWarnings("unchecked")
-    public void getSubBlocks(Item aItem, CreativeTabs par2CreativeTabs, List aList) {
+    public void getSubBlocks(Item item, CreativeTabs tab, List<ItemStack> list) {
         for (int i = 0; i <= 15; i++) {
-            aList.add(new ItemStack(aItem, 1, i));
+            list.add(new ItemStack(item, 1, i));
         }
     }
 }

src/main/java/com/gtnewhorizon/structurelib/command/CommandConfigureChannels.java

@@ -26,7 +26,7 @@ public class CommandConfigureChannels extends CommandBase {
     public String getCommandUsage(ICommandSender p_71518_1_) {
         return "/sl_channel <wipe/getall>\n" + "/sl_channel <get/unset> <channel name>\n"
                 + "/sl_channel <set> <channel name> <value>\n"
-                + "<channel name> can have space in it. <value> must be positive integer";
+                + "<channel name> can have space in it. Values below 1 clear the channel";
     }
 
     @Override
@@ -45,9 +45,7 @@ public class CommandConfigureChannels extends CommandBase {
     public void processCommand(ICommandSender sender, String[] args) {
         if (args.length == 0) throw new WrongUsageException(getCommandUsage(sender));
 
-        if (!(sender instanceof EntityPlayerMP)) throw new WrongUsageException("must be a player");
-
-        EntityPlayerMP player = (EntityPlayerMP) sender;
+        if (!(sender instanceof EntityPlayerMP player)) throw new WrongUsageException("must be a player");
 
         ItemStack heldItem = player.getHeldItem();
         if (heldItem == null || !(heldItem.getItem() instanceof ItemConstructableTrigger)) {
@@ -110,11 +108,14 @@ public class CommandConfigureChannels extends CommandBase {
                     throw new WrongUsageException("%s not a valid value", args[args.length - 1]);
                 }
 
-                if (value <= 0) throw new WrongUsageException("%s not a valid value", args[args.length - 1]);
-
-                ChannelDataAccessor.setChannelData(heldItem, channel, value);
+                if (value < 1) {
+                    ChannelDataAccessor.unsetChannelData(heldItem, channel);
+                } else {
+                    ChannelDataAccessor.setChannelData(heldItem, channel, value);
+                }
                 player.inventoryContainer.detectAndSendChanges();
-                sender.addChatMessage(new ChatComponentText(channel + " value: " + value));
+                sender.addChatMessage(
+                        new ChatComponentText(value < 1 ? channel + " no value" : channel + " value: " + value));
                 break;
         }
     }

src/main/java/com/gtnewhorizon/structurelib/command/CommandRegistryDebug.java

@@ -39,9 +39,7 @@ public class CommandRegistryDebug extends CommandBase {
     public void processCommand(ICommandSender sender, String[] args) {
         if (args.length != 1) throw new WrongUsageException(getCommandUsage(sender));
 
-        if (!(sender instanceof EntityPlayerMP)) throw new WrongUsageException("must be a player");
-
-        EntityPlayerMP player = (EntityPlayerMP) sender;
+        if (!(sender instanceof EntityPlayerMP player)) throw new WrongUsageException("must be a player");
 
         SortedRegistry<?> registry = SortedRegistry.getRegistry(args[0]);
         if (registry == null) throw new WrongUsageException("registry not found");

src/main/java/com/gtnewhorizon/structurelib/core/StructureLibCore.java

@@ -1,5 +1,6 @@
 package com.gtnewhorizon.structurelib.core;
 
+import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.List;
 import java.util.Map;
@@ -7,7 +8,9 @@ import java.util.Set;
 
 import com.gtnewhorizon.gtnhmixins.IEarlyMixinLoader;
 
+import cpw.mods.fml.relauncher.FMLLaunchHandler;
 import cpw.mods.fml.relauncher.IFMLLoadingPlugin;
+import cpw.mods.fml.relauncher.Side;
 
 @IFMLLoadingPlugin.MCVersion("1.7.10")
 public class StructureLibCore implements IFMLLoadingPlugin, IEarlyMixinLoader {
@@ -44,6 +47,11 @@ public class StructureLibCore implements IFMLLoadingPlugin, IEarlyMixinLoader {
 
     @Override
     public List<String> getMixins(Set<String> loadedCoreMods) {
-        return Arrays.asList("blockChangeNotifier.MixinForgeHooks", "blockChangeNotifier.MixinWorld");
+        List<String> mixins = new ArrayList<>(
+                Arrays.asList("blockChangeNotifier.MixinForgeHooks", "blockChangeNotifier.MixinWorld"));
+        if (FMLLaunchHandler.side() == Side.CLIENT) {
+            mixins.add("MixinGuiContainer_PickChannel");
+        }
+        return mixins;
     }
 }

src/main/java/com/gtnewhorizon/structurelib/gui/GuiScreenConfigureChannels.java

@@ -64,6 +64,9 @@ public class GuiScreenConfigureChannels extends GuiContainer implements IGuiScre
     private GuiTextField key, value;
     protected int guiTop, guiLeft;
     private List<String> info;
+    private boolean wipePending = false;
+    private long wipePendingTime = 0;
+    private static final long WIPE_CONFIRM_TIMEOUT_MS = 3000;
 
     public GuiScreenConfigureChannels(Container container, ItemStack trigger) {
         super(container);
@@ -346,9 +349,17 @@ public class GuiScreenConfigureChannels extends GuiContainer implements IGuiScre
                 ChannelDataAccessor.unsetChannelData(trigger, key.getText());
                 break;
             case WIPE_BTN:
-                ChannelDataAccessor.wipeChannelData(trigger);
-                key.setText("");
-                this.value.setText("");
+                if (!wipePending) {
+                    wipePending = true;
+                    wipePendingTime = System.currentTimeMillis();
+                    btn.displayString = I18n.format(I18N_PREFIX + "wipe.confirm");
+                } else {
+                    wipePending = false;
+                    btn.displayString = I18n.format(I18N_PREFIX + "wipe");
+                    ChannelDataAccessor.wipeChannelData(trigger);
+                    key.setText("");
+                    this.value.setText("");
+                }
                 break;
         }
 
@@ -369,6 +380,10 @@ public class GuiScreenConfigureChannels extends GuiContainer implements IGuiScre
         super.updateScreen();
         key.updateCursorCounter();
         value.updateCursorCounter();
+        if (wipePending && System.currentTimeMillis() - wipePendingTime > WIPE_CONFIRM_TIMEOUT_MS) {
+            wipePending = false;
+            getButtonList().get(WIPE_BTN).displayString = I18n.format(I18N_PREFIX + "wipe");
+        }
     }
 
     @Override

src/main/java/com/gtnewhorizon/structurelib/item/ItemBlockHint.java

@@ -21,10 +21,9 @@ public class ItemBlockHint extends ItemBlock {
     }
 
     @Override
-    @SuppressWarnings("unchecked")
-    public void addInformation(ItemStack aStack, EntityPlayer aPlayer, List aList, boolean aF3_H) {
-        aList.add(translateToLocal("structurelib.blockhint.desc.0")); // Helps while building
-        switch (aStack.getItemDamage()) {
+    public void addInformation(ItemStack stack, EntityPlayer player, List<String> tooltip, boolean adv) {
+        tooltip.add(translateToLocal("structurelib.blockhint.desc.0")); // Helps while building
+        switch (stack.getItemDamage()) {
             case 0:
             case 1:
             case 2:
@@ -37,35 +36,36 @@ public class ItemBlockHint extends ItemBlock {
             case 9:
             case 10:
             case 11:
-                aList.add(
+                // Placeholder for a certain group.
+                tooltip.add(
                         EnumChatFormatting.AQUA.toString() + EnumChatFormatting.BOLD
-                                + translateToLocal("structurelib.blockhint.desc.1")); // Placeholder for a certain
-                                                                                      // group.
+                                + translateToLocal("structurelib.blockhint.desc.1"));
                 break;
             case 12:
-                aList.add(
+                // General placeholder.
+                tooltip.add(
                         EnumChatFormatting.AQUA.toString() + EnumChatFormatting.BOLD
-                                + translateToLocal("structurelib.blockhint.desc.2")); // General placeholder.
+                                + translateToLocal("structurelib.blockhint.desc.2"));
                 break;
             case 13:
-                aList.add(
+                // Make sure it contains Air material.
+                tooltip.add(
                         EnumChatFormatting.AQUA.toString() + EnumChatFormatting.BOLD
-                                + translateToLocal("structurelib.blockhint.desc.3")); // Make sure it contains Air
-                                                                                      // material.
+                                + translateToLocal("structurelib.blockhint.desc.3"));
                 break;
             case 14:
-                aList.add(
+                // Make sure it does not contain Air material.
+                tooltip.add(
                         EnumChatFormatting.AQUA.toString() + EnumChatFormatting.BOLD
-                                + translateToLocal("structurelib.blockhint.desc.4")); // Make sure it does not contain
-                                                                                      // Air material.
+                                + translateToLocal("structurelib.blockhint.desc.4"));
                 break;
             case 15:
-                aList.add(EnumChatFormatting.BLUE + translateToLocal("structurelib.blockhint.desc.5")); // ERROR, what
-                                                                                                        // did u expect?
+                // ERROR, what did u expect?
+                tooltip.add(EnumChatFormatting.BLUE + translateToLocal("structurelib.blockhint.desc.5"));
                 break;
             default: // WTF?
-                aList.add("Damn son where did you get that!?");
-                aList.add(EnumChatFormatting.BLUE + "From outer space... I guess...");
+                tooltip.add("Damn son where did you get that!?");
+                tooltip.add(EnumChatFormatting.BLUE + "From outer space... I guess...");
         }
     }
 

src/main/java/com/gtnewhorizon/structurelib/item/ItemConstructableTrigger.java

@@ -45,31 +45,30 @@ public class ItemConstructableTrigger extends Item {
         return ConstructableUtility.handle(stack, player, world, x, y, z, side);
     }
 
-    @SuppressWarnings("unchecked")
     @Override
-    public void addInformation(ItemStack aStack, EntityPlayer ep, List aList, boolean boo) {
+    public void addInformation(ItemStack stack, EntityPlayer player, List<String> tooltip, boolean adv) {
         if (Keyboard.isKeyDown(Keyboard.KEY_LSHIFT)) {
-            aList.add(
+            tooltip.add(
                     translateToLocalFormatted(
                             "item.structurelib.constructableTrigger.desc.lshift.0",
-                            ChannelDataAccessor.countChannelData(aStack)));
-            ChannelDataAccessor.iterateChannelData(aStack).map(e -> e.getKey() + ": " + e.getValue())
-                    .forEach(aList::add);
+                            ChannelDataAccessor.countChannelData(stack)));
+            ChannelDataAccessor.iterateChannelData(stack).map(e -> e.getKey() + ": " + e.getValue())
+                    .forEach(tooltip::add);
         } else {
-            aList.add(translateToLocal("item.structurelib.constructableTrigger.desc.0")); // Triggers Constructable
-                                                                                          // Interface
-            aList.add(BLUE + translateToLocal("item.structurelib.constructableTrigger.desc.1")); // Shows multiblock
-                                                                                                 // construction
-                                                                                                 // details,
-            aList.add(BLUE + translateToLocal("item.structurelib.constructableTrigger.desc.2")); // just Use on a
-                                                                                                 // multiblock
-                                                                                                 // controller.
-            aList.add(BLUE + translateToLocal("item.structurelib.constructableTrigger.desc.3")); // (Sneak Use in
-                                                                                                 // creative to build)
-            aList.add(BLUE + translateToLocal("item.structurelib.constructableTrigger.desc.4")); // Quantity affects
-                                                                                                 // tier/mode/type
-            if (ChannelDataAccessor.hasSubChannel(aStack))
-                aList.add(translateToLocal("item.structurelib.constructableTrigger.desc.5"));
+            // Tooltip text:
+            // Triggers Constructable Interface
+            // Shows multiblock construction details,
+            // just Use on a multiblock controller.
+            // (Sneak Use in creative to build)
+            // Quantity affects tier/mode/type
+
+            tooltip.add(translateToLocal("item.structurelib.constructableTrigger.desc.0"));
+            tooltip.add(BLUE + translateToLocal("item.structurelib.constructableTrigger.desc.1"));
+            tooltip.add(BLUE + translateToLocal("item.structurelib.constructableTrigger.desc.2"));
+            tooltip.add(BLUE + translateToLocal("item.structurelib.constructableTrigger.desc.3"));
+            tooltip.add(BLUE + translateToLocal("item.structurelib.constructableTrigger.desc.4"));
+            if (ChannelDataAccessor.hasSubChannel(stack))
+                tooltip.add(translateToLocal("item.structurelib.constructableTrigger.desc.5"));
         }
     }
 }

src/main/java/com/gtnewhorizon/structurelib/item/ItemDebugConstructableTrigger.java

@@ -0,0 +1,14 @@
+package com.gtnewhorizon.structurelib.item;
+
+import static com.gtnewhorizon.structurelib.StructureLibAPI.MOD_ID;
+
+/**
+ * Hologram projector that always performs a creative build, whatever the player's game mode.
+ */
+public class ItemDebugConstructableTrigger extends ItemConstructableTrigger {
+
+    public ItemDebugConstructableTrigger() {
+        setUnlocalizedName("structurelib.debugConstructableTrigger");
+        setTextureName(MOD_ID + ":itemDebugConstructableTrigger");
+    }
+}

src/main/java/com/gtnewhorizon/structurelib/item/ItemFrontRotationTool.java

@@ -34,15 +34,14 @@ public class ItemFrontRotationTool extends Item {
 
     @Override
     @SideOnly(Side.CLIENT)
-    public void addInformation(ItemStack p_77624_1_, EntityPlayer p_77624_2_, List<String> aList, boolean p_77624_4_) {
-        aList.add(translateToLocal("item.structurelib.frontRotationTool.desc.0")); // Triggers Front Rotation Interface
-        aList.add(EnumChatFormatting.BLUE + translateToLocal("item.structurelib.frontRotationTool.desc.1")); // Rotates
-                                                                                                             // only the
-                                                                                                             // front
-                                                                                                             // panel,
-        aList.add(EnumChatFormatting.BLUE + translateToLocal("item.structurelib.frontRotationTool.desc.2")); // which
-                                                                                                             // allows
-                                                                                                             // structure
-                                                                                                             // rotation.
+    public void addInformation(ItemStack stack, EntityPlayer player, List<String> tooltip, boolean adv) {
+        // Tooltip Text:
+        // Triggers Front Rotation Interface
+        // Rotates only the front panel,
+        // which allows structure rotation.
+
+        tooltip.add(translateToLocal("item.structurelib.frontRotationTool.desc.0"));
+        tooltip.add(EnumChatFormatting.BLUE + translateToLocal("item.structurelib.frontRotationTool.desc.1"));
+        tooltip.add(EnumChatFormatting.BLUE + translateToLocal("item.structurelib.frontRotationTool.desc.2"));
     }
 }

src/main/java/com/gtnewhorizon/structurelib/mixins/early/MixinGuiContainer_PickChannel.java

@@ -0,0 +1,64 @@
+package com.gtnewhorizon.structurelib.mixins.early;
+
+import net.minecraft.client.Minecraft;
+import net.minecraft.client.gui.GuiScreen;
+import net.minecraft.client.gui.inventory.GuiContainer;
+import net.minecraft.entity.player.EntityPlayer;
+import net.minecraft.inventory.Slot;
+import net.minecraft.item.ItemStack;
+
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.gen.Invoker;
+import org.spongepowered.asm.mixin.injection.At;
+import org.spongepowered.asm.mixin.injection.Inject;
+import org.spongepowered.asm.mixin.injection.callback.CallbackInfo;
+
+import com.gtnewhorizon.structurelib.ChannelPickHandler;
+import com.gtnewhorizon.structurelib.ChannelWipeConfirmation;
+import com.gtnewhorizon.structurelib.StructureLib;
+import com.gtnewhorizon.structurelib.item.ItemConstructableTrigger;
+
+import codechicken.nei.NEIClientConfig;
+import codechicken.nei.guihook.GuiContainerManager;
+import cpw.mods.fml.common.Loader;
+
+@Mixin(value = GuiContainer.class, priority = 100)
+public abstract class MixinGuiContainer_PickChannel {
+
+    @Inject(method = "mouseClicked(III)V", at = @At("HEAD"), cancellable = true)
+    private void slib$onMouseClicked(int mouseX, int mouseY, int mouseButton, CallbackInfo ci) {
+        if (mouseButton != 2) return;
+
+        EntityPlayer player = Minecraft.getMinecraft().thePlayer;
+        if (player == null) return;
+
+        ItemStack cursorStack = player.inventory.getItemStack();
+        if (cursorStack == null || !(cursorStack.getItem() instanceof ItemConstructableTrigger)) return;
+
+        // Sink middle click as soon as projector is picked up
+        ci.cancel();
+
+        ItemStack hoveredStack = null;
+        try {
+            Slot slot = slib$invokeGetSlotAtPosition(mouseX, mouseY);
+            if (slot != null) {
+                hoveredStack = slot.getStack();
+            }
+
+            // try NEI
+            if (hoveredStack == null && Loader.isModLoaded("NotEnoughItems") && !NEIClientConfig.isHidden()) {
+                hoveredStack = GuiContainerManager.getStackMouseOver((GuiContainer) (Object) this);
+            }
+        } catch (Exception e) {
+            StructureLib.LOGGER.error("Error while resolving hovered slot for channel pick", e);
+        }
+
+        boolean isSneaking = GuiScreen.isShiftKeyDown();
+        if (isSneaking && !ChannelWipeConfirmation.confirm(player)) return;
+
+        ChannelPickHandler.handleMiddleClick(player, cursorStack, hoveredStack, isSneaking);
+    }
+
+    @Invoker("getSlotAtPosition")
+    protected abstract Slot slib$invokeGetSlotAtPosition(int x, int y);
+}

src/main/java/com/gtnewhorizon/structurelib/net/SetChannelDataMessage.java

@@ -23,15 +23,22 @@ import io.netty.buffer.ByteBuf;
 public class SetChannelDataMessage implements IMessage {
 
     private final List<Map.Entry<String, Integer>> data = new ArrayList<>();
+    private boolean onCursor;
 
     public SetChannelDataMessage() {}
 
     public SetChannelDataMessage(ItemStack trigger) {
+        this(trigger, false);
+    }
+
+    public SetChannelDataMessage(ItemStack trigger, final boolean onCursor) {
+        this.onCursor = onCursor;
         ChannelDataAccessor.iterateChannelData(trigger).forEach(data::add);
     }
 
     @Override
     public void fromBytes(ByteBuf buf) {
+        onCursor = buf.readBoolean();
         data.clear();
         int size = ByteBufUtils.readVarShort(buf);
         for (int i = 0; i < size; i++) {
@@ -41,6 +48,7 @@ public class SetChannelDataMessage implements IMessage {
 
     @Override
     public void toBytes(ByteBuf buf) {
+        buf.writeBoolean(onCursor);
         ByteBufUtils.writeVarShort(buf, data.size());
         for (Entry<String, Integer> e : data) {
             ByteBufUtils.writeUTF8String(buf, e.getKey());
@@ -53,11 +61,11 @@ public class SetChannelDataMessage implements IMessage {
         @Override
         public IMessage onMessage(SetChannelDataMessage message, MessageContext ctx) {
             EntityPlayerMP player = ctx.getServerHandler().playerEntity;
-            ItemStack heldItem = player.getHeldItem();
-            if (heldItem != null && heldItem.getItem() instanceof ItemConstructableTrigger) {
-                ChannelDataAccessor.wipeChannelData(heldItem);
+            ItemStack target = message.onCursor ? player.inventory.getItemStack() : player.getHeldItem();
+            if (target != null && target.getItem() instanceof ItemConstructableTrigger) {
+                ChannelDataAccessor.wipeChannelData(target);
                 for (Entry<String, Integer> e : message.data) {
-                    ChannelDataAccessor.setChannelData(heldItem, e.getKey(), e.getValue());
+                    ChannelDataAccessor.setChannelData(target, e.getKey(), e.getValue());
                 }
                 // since this is a set all channel request from the client, we would assume client already know
                 // what this would look like on the client, so no sync
@@ -65,7 +73,7 @@ public class SetChannelDataMessage implements IMessage {
                 StructureLib.LOGGER.warn(
                         "{} trying to set channel data on {}, which is not a hologram projector!",
                         player.getUniqueID(),
-                        heldItem);
+                        target);
             }
             return null;
         }

src/main/java/com/gtnewhorizon/structurelib/structure/ChatThrottleKey.java

@@ -14,9 +14,7 @@ class ChatThrottleKey {
         @Override
         public boolean equals(Object o) {
             if (this == o) return true;
-            if (!(o instanceof NoExplicitChannel)) return false;
-
-            NoExplicitChannel that = (NoExplicitChannel) o;
+            if (!(o instanceof NoExplicitChannel that)) return false;
 
             return subchannel.equals(that.subchannel);
         }

src/main/java/com/gtnewhorizon/structurelib/structure/IChannelDefinition.java

@@ -0,0 +1,98 @@
+package com.gtnewhorizon.structurelib.structure;
+
+/**
+ * Describes a channel used by one structure definition.
+ *
+ * <p>
+ * Channel values are integers stored on the constructable trigger item. Implementations may override the default
+ * validation and normalization policy when a simple bounded range is not sufficient.
+ * </p>
+ */
+public interface IChannelDefinition {
+
+    /**
+     * Creates a channel with a bounded inclusive range and clamping normalization.
+     *
+     * @param channel      channel identifier
+     * @param minimumValue inclusive minimum value
+     * @param maximumValue inclusive maximum value
+     * @return bounded channel definition
+     */
+    static IChannelDefinition bounded(String channel, int minimumValue, int maximumValue) {
+        if (minimumValue < 1 || maximumValue < minimumValue) {
+            throw new IllegalArgumentException("Invalid channel bounds");
+        }
+        return new IChannelDefinition() {
+
+            @Override
+            public String getChannel() {
+                return channel;
+            }
+
+            @Override
+            public int getMinimumValue() {
+                return minimumValue;
+            }
+
+            @Override
+            public int getMaximumValue() {
+                return maximumValue;
+            }
+        };
+    }
+
+    /**
+     * Creates a channel accepting every positive integer.
+     *
+     * @param channel channel identifier
+     * @return unbounded channel definition
+     */
+    static IChannelDefinition unbounded(String channel) {
+        return () -> channel;
+    }
+
+    /**
+     * Returns the lower-case channel identifier.
+     *
+     * @return channel identifier
+     */
+    String getChannel();
+
+    /**
+     * Returns the smallest value advertised by this definition. The default is {@code 1}.
+     *
+     * @return minimum value
+     */
+    default int getMinimumValue() {
+        return 1;
+    }
+
+    /**
+     * Returns the largest value advertised by this definition. The default is {@link java.lang.Integer#MAX_VALUE}.
+     *
+     * @return maximum value
+     */
+    default int getMaximumValue() {
+        return Integer.MAX_VALUE;
+    }
+
+    /**
+     * Checks whether a value is already valid without normalization.
+     *
+     * @param value value to check
+     * @return true when the value is valid
+     */
+    default boolean isValueValid(int value) {
+        return value >= getMinimumValue() && value <= getMaximumValue();
+    }
+
+    /**
+     * Converts a stored value to the value used by the structure definition.
+     *
+     * @param value stored value
+     * @return normalized value
+     */
+    default int normalizeValue(int value) {
+        return Math.max(getMinimumValue(), Math.min(getMaximumValue(), value));
+    }
+}

src/main/java/com/gtnewhorizon/structurelib/structure/IStructureDefinition.java

@@ -3,6 +3,8 @@ package com.gtnewhorizon.structurelib.structure;
 import static com.gtnewhorizon.structurelib.structure.IStructureWalker.ignoreBlockUnloaded;
 import static com.gtnewhorizon.structurelib.structure.IStructureWalker.skipBlockUnloaded;
 
+import java.util.Collection;
+import java.util.Collections;
 import java.util.function.Function;
 
 import net.minecraft.entity.player.EntityPlayer;
@@ -56,6 +58,48 @@ import com.gtnewhorizon.structurelib.alignment.enumerable.ExtendedFacing;
  */
 public interface IStructureDefinition<T> {
 
+    /**
+     * Returns channel definitions declared by this structure.
+     *
+     * @return an immutable or otherwise read-only channel collection
+     */
+    default Collection<IChannelDefinition> getChannelDefinitions() {
+        return Collections.emptyList();
+    }
+
+    /**
+     * Returns channel definitions explicitly added by the structure builder.
+     *
+     * @return explicitly declared channel definitions
+     */
+    default Collection<IChannelDefinition> getExplicitChannelDefinitions() {
+        return getChannelDefinitions();
+    }
+
+    /**
+     * Finds a channel definition by identifier.
+     *
+     * @param channel channel identifier
+     * @return channel definition, or {@code null} when it is not declared
+     */
+    default IChannelDefinition getChannelDefinition(String channel) {
+        for (IChannelDefinition definition : getChannelDefinitions()) {
+            if (definition.getChannel().equals(channel)) return definition;
+        }
+        return null;
+    }
+
+    /**
+     * Reads one channel using the standard trigger-item channel semantics.
+     *
+     * @param trigger trigger item containing channel data
+     * @param channel channel identifier
+     * @return stored channel data, or the trigger stack size when absent
+     */
+    default int getChannelData(ItemStack trigger, String channel) {
+        return ChannelDataAccessor.getChannelData(trigger, channel);
+    }
+
     /**
      * Used internally
      * <p>

src/main/java/com/gtnewhorizon/structurelib/structure/IStructureElement.java

@@ -4,7 +4,9 @@ import static com.gtnewhorizon.structurelib.StructureLib.LOGGER;
 import static com.gtnewhorizon.structurelib.StructureLib.PANIC_MODE;
 
 import java.util.Arrays;
+import java.util.Collection;
 import java.util.Collections;
+import java.util.List;
 import java.util.function.Consumer;
 import java.util.function.Predicate;
 
@@ -32,6 +34,15 @@ public interface IStructureElement<T> {
 
     boolean check(T t, World world, int x, int y, int z);
 
+    /**
+     * Returns the channels used by this element.
+     *
+     * @return lower-case channel identifiers
+     */
+    default Collection<String> getChannels() {
+        return Collections.emptySet();
+    }
+
     /**
      * Pure (stateless and side effect free) function to test if current block could be valid. Used to give user hints
      * about incorrectly placed blocks given a controller and trigger item. If couldBeValid(...) == false for a set of
@@ -42,6 +53,30 @@ public interface IStructureElement<T> {
         return true;
     }
 
+    /**
+     * Returns a human-readable description of what block(s) this element accepts. Used for diagnostic messages when
+     * structure checks fail (e.g. "expected Input Bus at (1, 2, 3)").
+     * <p>
+     * Unlike {@link #getBlocksToPlace}, which returns the full set of concrete block variants for autoplacing (e.g.
+     * every tier of Input Bus), this method returns <b>category-level</b> descriptions suitable for display to the
+     * player (e.g. just "Input Bus"). It also requires no parameters, no world, trigger item, or environment, making it
+     * usable in contexts where those are unavailable.
+     * <p>
+     * Implementations should return <b>lang keys</b> (e.g. {@code "tile.blockGlass.name"}) rather than pre-translated
+     * display names. The caller is responsible for translating these keys on the client side via
+     * {@code StatCollector.translateToLocal()}. If a key has no matching translation, {@code translateToLocal} returns
+     * the input string unchanged, so pre-translated fallback strings also work.
+     *
+     * @param context the context object (e.g. the multiblock controller), used to determine state-dependent
+     *                descriptions
+     * @return a list of accepted block descriptions as lang keys (or display names as fallback), or null if no
+     *         description is available
+     */
+    @Nullable
+    default List<String> getDescription(T context) {
+        return null;
+    }
+
     boolean spawnHint(T t, World world, int x, int y, int z, ItemStack trigger);
 
     boolean placeBlock(T t, World world, int x, int y, int z, ItemStack trigger);
@@ -71,7 +106,7 @@ public interface IStructureElement<T> {
                 "Default implementation of survivalPlaceBlock hit! Things aren't going to work well! IStructureElement class: {}",
                 getClass().getName());
         if (!StructureLibAPI.isBlockTriviallyReplaceable(world, x, y, z, actor)) return PlaceResult.REJECT;
-        return PlaceResult.SKIP;
+        return PlaceResult.REJECT_CONTINUE;
     }
 
     /**
@@ -181,7 +216,7 @@ public interface IStructureElement<T> {
         if (StructureLibAPI.isDebugEnabled()) LOGGER.info(
                 "Fallback shim code of survivalPlaceBlock hit! Things aren't going to work well! IStructureElement class: {}",
                 getClass().getName());
-        return PlaceResult.SKIP;
+        return PlaceResult.REJECT_CONTINUE;
     }
 
     /**
@@ -204,6 +239,12 @@ public interface IStructureElement<T> {
             public boolean spawnHint(T t, World world, int x, int y, int z, ItemStack trigger) {
                 return IStructureElement.this.spawnHint(t, world, x, y, z, trigger);
             }
+
+            @Nullable
+            @Override
+            public List<String> getDescription(T context) {
+                return IStructureElement.this.getDescription(context);
+            }
         };
     }
 
@@ -237,16 +278,21 @@ public interface IStructureElement<T> {
 
     enum PlaceResult {
         /**
-         * This element either exists already, or does not yet have an implementation for survivalPlaceBlock, or some
-         * other unforeseen situations. TODO this definition doesn't seem right. Should we separate SKIP from EXISTS, or
-         * SKIP from ERROR?
+         * The element's check passed, the position is already valid. No placement is needed. In the walker: continue
+         * iteration (no error, not counted as placed). In ofChain: short-circuits, remaining alternatives are skipped.
          */
         SKIP,
         /**
-         * This element's space is occupied by other stuff and require player attention, or player missing required
-         * resource, or the block cannot be placed due to obscure mechanisms, or some other unforeseen situations.
+         * The element cannot handle this position (occupied, missing resources, etc.). In the walker: stop iteration
+         * with error particles. In ofChain: try next alternative.
          */
         REJECT,
+        /**
+         * This element has no survivalPlaceBlock implementation (default fallback), or otherwise cannot place but is
+         * not an error condition. In the walker: continue iteration silently (like SKIP). In ofChain: try next
+         * alternative (like REJECT), so a better-suited element can handle it.
+         */
+        REJECT_CONTINUE,
         /**
          * Autoplace cannot proceed within this tick. To proceed further would require stopping the placement and wait
          * for next round.

src/main/java/com/gtnewhorizon/structurelib/structure/IStructureElementChain.java

@@ -1,7 +1,9 @@
 package com.gtnewhorizon.structurelib.structure;
 
 import java.util.ArrayList;
+import java.util.LinkedHashSet;
 import java.util.List;
+import java.util.Set;
 import java.util.function.Consumer;
 import java.util.function.Predicate;
 
@@ -61,6 +63,19 @@ public interface IStructureElementChain<T> extends IStructureElement<T> {
         return false;
     }
 
+    @Nullable
+    @Override
+    default List<String> getDescription(T context) {
+        Set<String> descriptions = new LinkedHashSet<>();
+        for (IStructureElement<T> fallback : fallbacks()) {
+            List<String> desc = fallback.getDescription(context);
+            if (desc != null) {
+                descriptions.addAll(desc);
+            }
+        }
+        return descriptions.isEmpty() ? null : new ArrayList<>(descriptions);
+    }
+
     @Nullable
     @Override
     default BlocksToPlace getBlocksToPlace(T t, World world, int x, int y, int z, ItemStack trigger,
@@ -82,47 +97,51 @@ public interface IStructureElementChain<T> extends IStructureElement<T> {
     @Override
     default PlaceResult survivalPlaceBlock(T t, World world, int x, int y, int z, ItemStack trigger, IItemSource s,
             EntityPlayerMP actor, Consumer<IChatComponent> chatter) {
-        boolean haveSkip = false;
+        boolean allContinue = true;
         List<IChatComponent> bufferedNoise = new ArrayList<>();
         for (IStructureElement<T> fallback : fallbacks()) {
             PlaceResult result = fallback.survivalPlaceBlock(t, world, x, y, z, trigger, s, actor, bufferedNoise::add);
             switch (result) {
+                case REJECT_CONTINUE:
+                    break;
                 case REJECT:
+                    allContinue = false;
                     break;
                 case SKIP:
-                    haveSkip = true;
-                    break;
+                    bufferedNoise.forEach(chatter);
+                    return PlaceResult.SKIP;
                 default:
                     return result;
             }
         }
         // dump all that noise back into upstream
         bufferedNoise.forEach(chatter);
-        // TODO need reconsider to ensure this is the right course of action
-        return haveSkip ? PlaceResult.SKIP : PlaceResult.REJECT;
+        return allContinue ? PlaceResult.REJECT_CONTINUE : PlaceResult.REJECT;
     }
 
     @Override
     default PlaceResult survivalPlaceBlock(T t, World world, int x, int y, int z, ItemStack trigger,
             AutoPlaceEnvironment env) {
-        boolean haveSkip = false;
+        boolean allContinue = true;
         List<IChatComponent> bufferedNoise = new ArrayList<>();
         for (IStructureElement<T> fallback : fallbacks()) {
             PlaceResult result = fallback
                     .survivalPlaceBlock(t, world, x, y, z, trigger, env.withChatter(bufferedNoise::add));
             switch (result) {
+                case REJECT_CONTINUE:
+                    break;
                 case REJECT:
+                    allContinue = false;
                     break;
                 case SKIP:
-                    haveSkip = true;
-                    break;
+                    bufferedNoise.forEach(env.getChatter());
+                    return PlaceResult.SKIP;
                 default:
                     return result;
             }
         }
         // dump all that noise back into upstream
         bufferedNoise.forEach(env.getChatter());
-        // TODO need reconsider to ensure this is the right course of action
-        return haveSkip ? PlaceResult.SKIP : PlaceResult.REJECT;
+        return allContinue ? PlaceResult.REJECT_CONTINUE : PlaceResult.REJECT;
     }
 }

src/main/java/com/gtnewhorizon/structurelib/structure/IStructureElementCheckOnly.java

@@ -27,12 +27,12 @@ public interface IStructureElementCheckOnly<T> extends IStructureElement<T> {
     @Override
     default PlaceResult survivalPlaceBlock(T t, World world, int x, int y, int z, ItemStack trigger, IItemSource s,
             EntityPlayerMP actor, Consumer<IChatComponent> chatter) {
-        return PlaceResult.SKIP;
+        return PlaceResult.REJECT_CONTINUE;
     }
 
     @Override
     default PlaceResult survivalPlaceBlock(T t, World world, int x, int y, int z, ItemStack trigger,
             AutoPlaceEnvironment env) {
-        return PlaceResult.SKIP;
+        return PlaceResult.REJECT_CONTINUE;
     }
 }

src/main/java/com/gtnewhorizon/structurelib/structure/LazyStructureElement.java

@@ -1,5 +1,6 @@
 package com.gtnewhorizon.structurelib.structure;
 
+import java.util.List;
 import java.util.function.Consumer;
 import java.util.function.Function;
 
@@ -65,4 +66,10 @@ class LazyStructureElement<T> implements IStructureElementDeferred<T> {
             AutoPlaceEnvironment env) {
         return get(t).survivalPlaceBlock(t, world, x, y, z, trigger, env);
     }
+
+    @Nullable
+    @Override
+    public List<String> getDescription(T context) {
+        return elem != null ? elem.getDescription(context) : null;
+    }
 }

src/main/java/com/gtnewhorizon/structurelib/structure/StructureDefinition.java

@@ -5,8 +5,12 @@ import static com.gtnewhorizon.structurelib.structure.StructureUtility.notAir;
 import static com.gtnewhorizon.structurelib.structure.StructureUtility.step;
 
 import java.util.Arrays;
+import java.util.BitSet;
+import java.util.Collection;
+import java.util.Collections;
 import java.util.HashMap;
 import java.util.HashSet;
+import java.util.Locale;
 import java.util.Map;
 import java.util.NoSuchElementException;
 import java.util.Set;
@@ -19,18 +23,28 @@ public class StructureDefinition<T> implements IStructureDefinition<T> {
     private final Map<Character, IStructureElement<T>> elements;
     private final Map<String, String> shapes;
     private final Map<String, IStructureElement<T>[]> structures;
-    private final Map<String, Set<Vec3Impl>> occupiedSpaces;
+    private final Map<String, OccupiedSpace> occupiedSpaces;
+    private final Map<String, IChannelDefinition> channelDefinitions;
+    private final Set<String> explicitChannels;
+    private final Collection<IChannelDefinition> channelDefinitionValues;
+    private final Collection<IChannelDefinition> explicitChannelDefinitions;
 
     public static <B> Builder<B> builder() {
         return new Builder<>();
     }
 
     private StructureDefinition(Map<Character, IStructureElement<T>> elements, Map<String, String> shapes,
-            Map<String, IStructureElement<T>[]> structures, Map<String, Set<Vec3Impl>> occupiedSpaces) {
+            Map<String, IStructureElement<T>[]> structures, Map<String, OccupiedSpace> occupiedSpaces,
+            Map<String, IChannelDefinition> channelDefinitions, Set<String> explicitChannels) {
         this.elements = elements;
         this.shapes = shapes;
         this.structures = structures;
         this.occupiedSpaces = occupiedSpaces;
+        this.channelDefinitions = Collections.unmodifiableMap(new HashMap<>(channelDefinitions));
+        this.explicitChannels = Collections.unmodifiableSet(new HashSet<>(explicitChannels));
+        this.channelDefinitionValues = Collections.unmodifiableCollection(this.channelDefinitions.values());
+        this.explicitChannelDefinitions = Collections.unmodifiableList(
+                this.explicitChannels.stream().map(this.channelDefinitions::get).collect(Collectors.toList()));
     }
 
     public static class Builder<T> {
@@ -42,13 +56,17 @@ public class StructureDefinition<T> implements IStructureDefinition<T> {
         private final Map<Vec3Impl, Character> navigates;
         private final Map<Character, IStructureElement<T>> elements;
         private final Map<String, String> shapes;
-        private final Map<String, Set<Vec3Impl>> occupiedSpaces;
+        private final Map<String, OccupiedSpace> occupiedSpaces;
+        private final Map<String, IChannelDefinition> channels;
+        private final Set<String> explicitChannels;
 
         private Builder() {
             navigates = new HashMap<>();
             elements = new HashMap<>();
             shapes = new HashMap<>();
             occupiedSpaces = new HashMap<>();
+            channels = new HashMap<>();
+            explicitChannels = new HashSet<>();
         }
 
         public Map<Character, IStructureElement<T>> getElements() {
@@ -95,7 +113,19 @@ public class StructureDefinition<T> implements IStructureDefinition<T> {
                 }
                 builder.setLength(builder.length() - 1);
             }
-            Set<Vec3Impl> occupiedSpace = new HashSet<>();
+            int sizeA = 0;
+            int sizeB = 0;
+            long occupiedCount = 0;
+            for (String[] strings : structurePiece) {
+                sizeB = Math.max(sizeB, strings.length);
+                for (String string : strings) {
+                    sizeA = Math.max(sizeA, string.length());
+                    for (int i = 0; i < string.length(); i++) {
+                        if (string.charAt(i) != ' ') occupiedCount++;
+                    }
+                }
+            }
+            OccupiedSpace occupiedSpace = new OccupiedSpace(sizeA, sizeB, structurePiece.length, occupiedCount);
             // these track the global current location
             int aa = 0, bb = 0, cc = 0;
             // these track the vec3 towards next meaningful element
@@ -109,7 +139,7 @@ public class StructureDefinition<T> implements IStructureDefinition<T> {
                 } else if (ch == '~') {
                     builder.setCharAt(i, A);
                     ch = A;
-                    occupiedSpace.add(Vec3Impl.getFromPool(aa, bb, cc));
+                    occupiedSpace.add(aa, bb, cc);
                 }
                 if (ch == A) {
                     aa++;
@@ -135,28 +165,45 @@ public class StructureDefinition<T> implements IStructureDefinition<T> {
                         addElement(navigate, step(vec3));
                     }
                     builder.setCharAt(i - 1, navigate);
-                    occupiedSpace.add(Vec3Impl.getFromPool(aa, bb, cc));
+                    occupiedSpace.add(aa, bb, cc);
                     aa++;
                     a = 0;
                     b = 0;
                     c = 0;
                 } else {
-                    occupiedSpace.add(Vec3Impl.getFromPool(aa, bb, cc));
+                    occupiedSpace.add(aa, bb, cc);
                     aa++;
                 }
             }
 
             occupiedSpaces.put(name, occupiedSpace);
 
-            String built = builder.toString().replaceAll("[\\uA000\\uB000\\uC000]", "");
+            boolean hasPlus = false;
+            boolean hasMinus = false;
 
-            if (built.contains("+")) {
+            int write = 0;
+            for (int read = 0; read < builder.length(); read++) {
+                char ch = builder.charAt(read);
+                if (ch == A || ch == B || ch == C) {
+                    continue;
+                }
+                if (ch == '+') {
+                    hasPlus = true;
+                } else if (ch == '-') {
+                    hasMinus = true;
+                }
+                if (read != write) builder.setCharAt(write, ch);
+                write++;
+            }
+            builder.setLength(write);
+
+            if (hasPlus) {
                 addElement('+', notAir());
             }
-            if (built.contains("-")) {
+            if (hasMinus) {
                 addElement('-', isAir());
             }
-            shapes.put(name, built);
+            shapes.put(name, builder.toString());
             return this;
         }
 
@@ -165,22 +212,61 @@ public class StructureDefinition<T> implements IStructureDefinition<T> {
          */
         @Deprecated
         public Builder<T> addElement(Character name, IStructureElement<T> structurePiece) {
-            elements.putIfAbsent(name, structurePiece);
+            if (elements.putIfAbsent(name, structurePiece) == null) registerElementChannel(structurePiece);
             return this;
         }
 
         public Builder<T> addElement(char name, IStructureElement<T> structurePiece) {
-            elements.putIfAbsent(name, structurePiece);
+            if (elements.putIfAbsent(name, structurePiece) == null) registerElementChannel(structurePiece);
             return this;
         }
 
+        public Builder<T> addChannel(IChannelDefinition definition) {
+            validateChannelDefinition(definition);
+            channels.put(definition.getChannel(), definition);
+            explicitChannels.add(definition.getChannel());
+            return this;
+        }
+
+        public Builder<T> addChannel(String channel, int minimumValue, int maximumValue) {
+            return addChannel(IChannelDefinition.bounded(channel, minimumValue, maximumValue));
+        }
+
+        private void registerElementChannel(IStructureElement<T> structurePiece) {
+            for (String channel : structurePiece.getChannels()) {
+                validateChannelName(channel);
+                if (!explicitChannels.contains(channel)) {
+                    channels.putIfAbsent(channel, IChannelDefinition.unbounded(channel));
+                }
+            }
+        }
+
+        private void validateChannelDefinition(IChannelDefinition definition) {
+            if (definition == null) throw new IllegalArgumentException("Channel definition cannot be null");
+            validateChannelName(definition.getChannel());
+            if (definition.getMinimumValue() < 1 || definition.getMaximumValue() < definition.getMinimumValue()) {
+                throw new IllegalArgumentException("Invalid channel definition values");
+            }
+        }
+
+        private void validateChannelName(String channel) {
+            if (channel == null || channel.isEmpty() || !channel.toLowerCase(Locale.ROOT).equals(channel)) {
+                throw new IllegalArgumentException("Channel name must be non-empty and lower case");
+            }
+        }
+
         public IStructureDefinition<T> build() {
+            for (IStructureElement<T> element : elements.values()) {
+                registerElementChannel(element);
+            }
             Map<String, IStructureElement<T>[]> structures = compileStructureMap();
             return new StructureDefinition<>(
                     new HashMap<>(elements),
                     new HashMap<>(shapes),
                     structures,
-                    occupiedSpaces);
+                    occupiedSpaces,
+                    channels,
+                    explicitChannels);
         }
 
         @SuppressWarnings("unchecked")
@@ -233,6 +319,21 @@ public class StructureDefinition<T> implements IStructureDefinition<T> {
         return structures;
     }
 
+    @Override
+    public Collection<IChannelDefinition> getChannelDefinitions() {
+        return channelDefinitionValues;
+    }
+
+    @Override
+    public Collection<IChannelDefinition> getExplicitChannelDefinitions() {
+        return explicitChannelDefinitions;
+    }
+
+    @Override
+    public IChannelDefinition getChannelDefinition(String channel) {
+        return channelDefinitions.get(channel);
+    }
+
     @Override
     public IStructureElement<T>[] getStructureFor(String name) {
         IStructureElement<T>[] elements = structures.get(name);
@@ -242,8 +343,49 @@ public class StructureDefinition<T> implements IStructureDefinition<T> {
 
     @Override
     public boolean isContainedInStructure(String name, int offsetA, int offsetB, int offsetC) {
-        Set<Vec3Impl> occupiedSpace = occupiedSpaces.get(name);
+        OccupiedSpace occupiedSpace = occupiedSpaces.get(name);
         if (occupiedSpace == null) throw new NoSuchElementException(name);
-        return occupiedSpace.contains(new Vec3Impl(offsetA, offsetB, offsetC));
+        return occupiedSpace.contains(offsetA, offsetB, offsetC);
+    }
+
+    private static class OccupiedSpace {
+
+        private final int sizeA;
+        private final int sizeB;
+        private final int sizeC;
+        private final BitSet occupied;
+        private final Set<Vec3Impl> sparseOccupied;
+
+        private OccupiedSpace(int sizeA, int sizeB, int sizeC, long occupiedCount) {
+            this.sizeA = sizeA;
+            this.sizeB = sizeB;
+            this.sizeC = sizeC;
+            long volume = (long) sizeA * sizeB * sizeC;
+            if (volume <= Integer.MAX_VALUE && volume <= Math.max(1024L, occupiedCount * 256L)) {
+                occupied = new BitSet((int) volume);
+                sparseOccupied = null;
+            } else {
+                occupied = null;
+                sparseOccupied = new HashSet<>();
+            }
+        }
+
+        private void add(int a, int b, int c) {
+            if (occupied != null) {
+                occupied.set(index(a, b, c));
+            } else {
+                sparseOccupied.add(new Vec3Impl(a, b, c));
+            }
+        }
+
+        private boolean contains(int a, int b, int c) {
+            if (a < 0 || b < 0 || c < 0 || a >= sizeA || b >= sizeB || c >= sizeC) return false;
+            if (occupied != null) return occupied.get(index(a, b, c));
+            return sparseOccupied.contains(new Vec3Impl(a, b, c));
+        }
+
+        private int index(int a, int b, int c) {
+            return (c * sizeB + b) * sizeA + a;
+        }
     }
 }

src/main/java/com/gtnewhorizon/structurelib/structure/StructureUtility.java

@@ -4,12 +4,14 @@ import static com.gtnewhorizon.structurelib.StructureLib.LOGGER;
 import static com.gtnewhorizon.structurelib.StructureLib.PANIC_MODE;
 import static java.lang.Integer.MIN_VALUE;
 
+import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collection;
 import java.util.Collections;
 import java.util.Comparator;
 import java.util.HashMap;
 import java.util.HashSet;
+import java.util.LinkedHashSet;
 import java.util.List;
 import java.util.Map;
 import java.util.Map.Entry;
@@ -30,15 +32,18 @@ import javax.annotation.Nullable;
 import net.minecraft.block.Block;
 import net.minecraft.entity.player.EntityPlayer;
 import net.minecraft.entity.player.EntityPlayerMP;
+import net.minecraft.event.HoverEvent;
 import net.minecraft.init.Blocks;
 import net.minecraft.item.Item;
 import net.minecraft.item.ItemBlock;
 import net.minecraft.item.ItemStack;
 import net.minecraft.nbt.NBTTagCompound;
 import net.minecraft.tileentity.TileEntity;
+import net.minecraft.util.ChatComponentText;
 import net.minecraft.util.ChatComponentTranslation;
 import net.minecraft.util.IChatComponent;
 import net.minecraft.util.IIcon;
+import net.minecraft.util.StatCollector;
 import net.minecraft.world.World;
 import net.minecraftforge.common.util.ForgeDirection;
 
@@ -314,6 +319,25 @@ public class StructureUtility {
         return survivalPlaceBlock(block, meta, world, x, y, z, s, (EntityPlayer) actor, chatter);
     }
 
+    /**
+     * Build a chat component naming the given stack, so that the receiving client localizes it.
+     * <p>
+     * Falls back to the server side display name for stacks whose name is not a plain translation key, e.g. items that
+     * assemble their name in {@link Item#getItemStackDisplayName(ItemStack)}.
+     */
+    private static IChatComponent getStackChatName(ItemStack stack) {
+        String key = stack.getUnlocalizedName() + ".name";
+        if (!StatCollector.canTranslate(key)) return stack.func_151000_E();
+        IChatComponent name = new ChatComponentText("[").appendSibling(new ChatComponentTranslation(key))
+                .appendText("]");
+        NBTTagCompound tag = new NBTTagCompound();
+        stack.writeToNBT(tag);
+        name.getChatStyle()
+                .setChatHoverEvent(new HoverEvent(HoverEvent.Action.SHOW_ITEM, new ChatComponentText(tag.toString())))
+                .setColor(stack.getRarity().rarityColor);
+        return name;
+    }
+
     /**
      * This is a helper method for implementing
      * {@link IStructureElement#survivalPlaceBlock(Object, World, int, int, int, ItemStack, IItemSource, EntityPlayerMP, Consumer)}
@@ -338,13 +362,10 @@ public class StructureUtility {
         ItemStack stack = new ItemStack(itemBlock, 1, itemMeta);
         if (!s.takeOne(stack, true)) {
             if (chatter != null) chatter.accept(
-                    new ChatComponentTranslation(
-                            "structurelib.autoplace.error.no_simple_block",
-                            stack.func_151000_E()));
+                    new ChatComponentTranslation("structurelib.autoplace.missing_block", getStackChatName(stack)));
             return PlaceResult.REJECT;
         }
-        if (block instanceof ICustomBlockSetting) {
-            ICustomBlockSetting blockCustom = (ICustomBlockSetting) block;
+        if (block instanceof ICustomBlockSetting blockCustom) {
             blockCustom.setBlock(world, x, y, z, meta);
         } else if (!stack.copy()
                 .tryPlaceItemIntoWorld(actor, world, x, y, z, ForgeDirection.UP.ordinal(), 0.5f, 0.5f, 0.5f)) {
@@ -447,7 +468,7 @@ public class StructureUtility {
         if (!StructureLibAPI.isBlockTriviallyReplaceable(world, x, y, z, actor)) return PlaceResult.REJECT;
         if (!assumeStackPresent && !s.takeOne(stack, true)) {
             if (chatter != null) chatter.accept(
-                    new ChatComponentTranslation("structurelib.autoplace.error.no_item_stack", stack.func_151000_E()));
+                    new ChatComponentTranslation("structurelib.autoplace.missing_block", getStackChatName(stack)));
             return PlaceResult.REJECT;
         }
         if (!stack.copy().tryPlaceItemIntoWorld(actor, world, x, y, z, ForgeDirection.UP.ordinal(), 0.5f, 0.5f, 0.5f))
@@ -637,7 +658,7 @@ public class StructureUtility {
      * given tier, then player will be allowed to use multiple kinds of blocks, but their tier is guaranteed to be the
      * same.
      * <p>
-     * <h3>WARNING</h3> <b>You SHOULD NOT return notSet from your tierExtractor.</b> If you do so, we will have this
+     * <h4>WARNING</h4> <b>You SHOULD NOT return notSet from your tierExtractor.</b> If you do so, we will have this
      * chain of events:
      * <ul>
      * <li>at check start, tier is reset to notSet
@@ -650,7 +671,7 @@ public class StructureUtility {
      * doing its business
      * <li>Player enjoy a (probably) hilariously shaped multi and (probably) reduced build cost.
      * </ul>
-     * <h3>Example Implementation</h3>
+     * <h4>Example Implementation</h4>
      * <p>
      * Assume you have 16 tier, each map to one particular block's 16 different meta. You will usually want something
      * like this
@@ -706,6 +727,29 @@ public class StructureUtility {
     public static <T, TIER> IStructureElement<T> ofBlocksTiered(ITierConverter<TIER> tierExtractor,
             @Nullable List<Pair<Block, Integer>> allKnownTiers, @Nullable TIER notSet, BiConsumer<T, TIER> setter,
             Function<T, TIER> getter) {
+        List<String> descriptions = null;
+        if (allKnownTiers != null) {
+            descriptions = new ArrayList<>();
+            for (Pair<Block, Integer> tier : allKnownTiers) {
+                Item item = Item.getItemFromBlock(tier.getLeft());
+                if (item != null) {
+                    descriptions.add(new ItemStack(item, 1, tier.getRight()).getUnlocalizedName() + ".name");
+                }
+            }
+        }
+        return ofBlocksTiered(tierExtractor, allKnownTiers, notSet, setter, getter, descriptions);
+    }
+
+    /**
+     * Like {@link #ofBlocksTiered(ITierConverter, List, Object, BiConsumer, Function)}, but with an explicit
+     * description that will be returned by {@link IStructureElement#getDescription(Object)}.
+     *
+     * @param description the description lang keys to attach to this element, or null for no description
+     * @see #ofBlocksTiered(ITierConverter, List, Object, BiConsumer, Function)
+     */
+    public static <T, TIER> IStructureElement<T> ofBlocksTiered(ITierConverter<TIER> tierExtractor,
+            @Nullable List<Pair<Block, Integer>> allKnownTiers, @Nullable TIER notSet, BiConsumer<T, TIER> setter,
+            Function<T, TIER> getter, @Nullable List<String> description) {
         List<Pair<Block, Integer>> hints = allKnownTiers == null ? Collections.emptyList() : allKnownTiers;
         if (hints.stream().anyMatch(Objects::isNull)) throw new IllegalArgumentException();
         IStructureElementCheckOnly<T> check = ofBlocksTiered(tierExtractor, notSet, setter, getter);
@@ -746,8 +790,7 @@ public class StructureUtility {
             public boolean placeBlock(T t, World world, int x, int y, int z, ItemStack trigger) {
                 Pair<Block, Integer> hint = getHint(trigger);
                 if (hint == null) return false;
-                if (hint.getKey() instanceof ICustomBlockSetting) {
-                    ICustomBlockSetting block = (ICustomBlockSetting) hint.getKey();
+                if (hint.getKey() instanceof ICustomBlockSetting block) {
                     block.setBlock(world, x, y, z, hint.getValue());
                 } else {
                     world.setBlock(x, y, z, hint.getKey(), hint.getValue(), 2);
@@ -767,7 +810,7 @@ public class StructureUtility {
             public PlaceResult survivalPlaceBlock(T t, World world, int x, int y, int z, ItemStack trigger,
                     AutoPlaceEnvironment env) {
                 Pair<Block, Integer> hint = getHint(trigger);
-                if (hint == null) return PlaceResult.REJECT; // TODO or SKIP?
+                if (hint == null) return PlaceResult.REJECT;
                 Block block = world.getBlock(x, y, z);
                 int meta = world.getBlockMetadata(x, y, z);
                 TIER tier = tierExtractor.convert(block, meta);
@@ -784,6 +827,24 @@ public class StructureUtility {
                         env.getActor(),
                         env.getChatter());
             }
+
+            @Nullable
+            @Override
+            public List<String> getDescription(T context) {
+                TIER currentTier = getter.apply(context);
+                if (Objects.equals(currentTier, notSet)) return description;
+
+                for (Pair<Block, Integer> pair : hints) {
+                    TIER pairTier = tierExtractor.convert(pair.getKey(), pair.getValue());
+                    if (!Objects.equals(pairTier, currentTier)) continue;
+                    Item item = Item.getItemFromBlock(pair.getKey());
+                    if (item == null) continue;
+                    return Collections
+                            .singletonList(new ItemStack(item, 1, pair.getValue()).getUnlocalizedName() + ".name");
+                }
+                return description;
+            }
+
         };
     }
 
@@ -1407,10 +1468,65 @@ public class StructureUtility {
                         AutoPlaceEnvironment env) {
                     return BlocksToPlace.create(block, meta);
                 }
+
+                @Nullable
+                @Override
+                public List<String> getDescription(T context) {
+                    Item item = Item.getItemFromBlock(block);
+                    if (item == null) return null;
+                    return Collections.singletonList(new ItemStack(item, 1, meta).getUnlocalizedName() + ".name");
+                }
             };
         } else {
             return new IStructureElement<T>() {
 
+                @Override
+                public PlaceResult survivalPlaceBlock(T t, World world, int x, int y, int z, ItemStack trigger,
+                        AutoPlaceEnvironment env) {
+                    BlocksToPlace e = getBlocksToPlace(t, world, x, y, z, trigger, env);
+                    IItemSource source = env.getSource();
+                    EntityPlayer actor = env.getActor();
+                    Consumer<IChatComponent> chatter = env.getChatter();
+                    if (check(t, world, x, y, z)) return PlaceResult.SKIP;
+                    if (e.getStacks() == null) {
+                        ItemStack taken = source.takeOne(e.getPredicate(), true);
+                        return StructureUtility.survivalPlaceBlock(
+                                taken,
+                                NBTMode.EXACT,
+                                taken.stackTagCompound,
+                                false,
+                                world,
+                                x,
+                                y,
+                                z,
+                                source,
+                                actor,
+                                chatter);
+                    }
+                    for (ItemStack stack : e.getStacks()) {
+                        if (!source.takeOne(stack, true)) {
+                            env.getChatter().accept(
+                                    new ChatComponentTranslation(
+                                            "structurelib.autoplace.missing_block",
+                                            getStackChatName(stack)));
+                            continue;
+                        }
+                        return StructureUtility.survivalPlaceBlock(
+                                stack,
+                                NBTMode.EXACT,
+                                stack.stackTagCompound,
+                                false,
+                                world,
+                                x,
+                                y,
+                                z,
+                                source,
+                                actor,
+                                chatter);
+                    }
+                    return PlaceResult.REJECT;
+                }
+
                 @Override
                 public boolean check(T t, World world, int x, int y, int z) {
                     Block worldBlock = world.getBlock(x, y, z);
@@ -1439,6 +1555,14 @@ public class StructureUtility {
                         AutoPlaceEnvironment env) {
                     return BlocksToPlace.create(block, meta);
                 }
+
+                @Nullable
+                @Override
+                public List<String> getDescription(T context) {
+                    Item item = Item.getItemFromBlock(block);
+                    if (item == null) return null;
+                    return Collections.singletonList(new ItemStack(item, 1, meta).getUnlocalizedName() + ".name");
+                }
             };
         }
     }
@@ -1481,6 +1605,14 @@ public class StructureUtility {
                     // there is getSubItems on ItemBlock, but it's client only
                     return BlocksToPlace.create(defaultBlock, defaultMeta);
                 }
+
+                @Nullable
+                @Override
+                public List<String> getDescription(T context) {
+                    Item item = Item.getItemFromBlock(block);
+                    if (item == null) return null;
+                    return Collections.singletonList(new ItemStack(item, 1, 0).getUnlocalizedName() + ".name");
+                }
             };
         } else {
             return new IStructureElement<T>() {
@@ -1513,6 +1645,14 @@ public class StructureUtility {
                     // there is getSubItems on ItemBlock, but it's client only
                     return BlocksToPlace.create(defaultBlock, defaultMeta);
                 }
+
+                @Nullable
+                @Override
+                public List<String> getDescription(T context) {
+                    Item item = Item.getItemFromBlock(block);
+                    if (item == null) return null;
+                    return Collections.singletonList(new ItemStack(item, 1, 0).getUnlocalizedName() + ".name");
+                }
             };
         }
     }
@@ -1776,6 +1916,71 @@ public class StructureUtility {
                     AutoPlaceEnvironment env) {
                 return element.survivalPlaceBlock(t, world, x, y, z, trigger, env);
             }
+
+            @Nullable
+            @Override
+            public List<String> getDescription(T context) {
+                return element.getDescription(context);
+            }
+        };
+    }
+
+    /**
+     * Wraps an element and overrides its description. Useful for providing human-readable names to elements whose
+     * underlying implementation doesn't provide a description (e.g. tiered block elements).
+     *
+     * @param description the description to use, or null to clear any existing description
+     * @param element     the element to wrap
+     */
+    public static <B extends IStructureElement<T>, T> IStructureElement<T> withDescription(
+            @Nullable List<String> description, B element) {
+        return new IStructureElement<T>() {
+
+            @Override
+            public boolean check(T t, World world, int x, int y, int z) {
+                return element.check(t, world, x, y, z);
+            }
+
+            @Override
+            public boolean couldBeValid(T t, World world, int x, int y, int z, ItemStack trigger) {
+                return element.couldBeValid(t, world, x, y, z, trigger);
+            }
+
+            @Override
+            public boolean placeBlock(T t, World world, int x, int y, int z, ItemStack trigger) {
+                return element.placeBlock(t, world, x, y, z, trigger);
+            }
+
+            @Override
+            public boolean spawnHint(T t, World world, int x, int y, int z, ItemStack trigger) {
+                return element.spawnHint(t, world, x, y, z, trigger);
+            }
+
+            @Nullable
+            @Override
+            public BlocksToPlace getBlocksToPlace(T t, World world, int x, int y, int z, ItemStack trigger,
+                    AutoPlaceEnvironment env) {
+                return element.getBlocksToPlace(t, world, x, y, z, trigger, env);
+            }
+
+            @Override
+            @Deprecated
+            public PlaceResult survivalPlaceBlock(T t, World world, int x, int y, int z, ItemStack trigger,
+                    IItemSource s, EntityPlayerMP actor, Consumer<IChatComponent> chatter) {
+                return element.survivalPlaceBlock(t, world, x, y, z, trigger, s, actor, chatter);
+            }
+
+            @Override
+            public PlaceResult survivalPlaceBlock(T t, World world, int x, int y, int z, ItemStack trigger,
+                    AutoPlaceEnvironment env) {
+                return element.survivalPlaceBlock(t, world, x, y, z, trigger, env);
+            }
+
+            @Nullable
+            @Override
+            public List<String> getDescription(T context) {
+                return description;
+            }
         };
     }
 
@@ -1832,6 +2037,12 @@ public class StructureUtility {
                     AutoPlaceEnvironment env) {
                 return element.survivalPlaceBlock(t, world, x, y, z, trigger, env);
             }
+
+            @Nullable
+            @Override
+            public List<String> getDescription(T context) {
+                return element.getDescription(context);
+            }
         };
     }
 
@@ -1840,11 +2051,11 @@ public class StructureUtility {
     /**
      * Enable this structure element only if given predicate returns true.
      * <p>
-     * Return SKIP when survival auto place if given predicate returns false.
+     * Return REJECT_CONTINUE when survival auto place if given predicate returns false.
      */
     public static <T> IStructureElement<T> onlyIf(Predicate<? super T> predicate,
             IStructureElement<? super T> downstream) {
-        return onlyIf(predicate, downstream, PlaceResult.SKIP);
+        return onlyIf(predicate, downstream, PlaceResult.REJECT_CONTINUE);
     }
 
     /**
@@ -1901,6 +2112,12 @@ public class StructureUtility {
                 if (predicate.test(t)) return downstream.survivalPlaceBlock(t, world, x, y, z, trigger, env);
                 return placeResultWhenDisabled;
             }
+
+            @Nullable
+            @Override
+            public List<String> getDescription(T context) {
+                return downstream.getDescription(context);
+            }
         };
     }
 
@@ -1913,10 +2130,10 @@ public class StructureUtility {
      * using {@link #isAir()}. It will not attempt to capture any errors though, so next one will not be tried if
      * previous one would crash.
      * <p>
-     * (*): For survival auto place, it will * REJECT, if all structure element REJECT * SKIP, if 1 or more structure
-     * element SKIP and the rest structure element (0 or more) REJECT * any other result, **immediately** upon any
-     * structure element returns these other results. This behavior is not 100% fixed and might change later on, but we
-     * will send the notice on a best effort basis.
+     * (*): For survival auto place, it will: REJECT, if any structure element returns REJECT (and none returned ACCEPT,
+     * STOP, ACCEPT_STOP, or SKIP); REJECT_CONTINUE, if all structure elements return REJECT_CONTINUE (none returned
+     * REJECT); SKIP, as soon as any structure element returns SKIP; any other result, immediately upon any structure
+     * element returning those.
      * <p>
      * Take care while chaining, as it will try to call every structure element until it returns true. If none does it
      * will finally return false.
@@ -1998,6 +2215,12 @@ public class StructureUtility {
                     AutoPlaceEnvironment env) {
                 return elem.survivalPlaceBlock(t.getCurrentContext(), world, x, y, z, trigger, env);
             }
+
+            @Nullable
+            @Override
+            public List<String> getDescription(T context) {
+                return elem.getDescription(context.getCurrentContext());
+            }
         };
     }
     // endregion
@@ -2607,7 +2830,7 @@ public class StructureUtility {
         if (keyExtractor == null || map == null) {
             throw new IllegalArgumentException();
         }
-        return defer(keyExtractorCheck.andThen(map::get), keyExtractor.<IStructureElement<T>>andThen(map::get));
+        return defer(keyExtractorCheck.andThen(map::get), keyExtractor.andThen(map::get));
     }
 
     /**
@@ -2771,7 +2994,14 @@ public class StructureUtility {
      * See channels.md in docs folder
      */
     public static <T> IStructureElement<T> withChannel(String channel, IStructureElement<T> backing) {
-        return new IStructureElement<T>() {
+        return new IStructureElement<>() {
+
+            private final Collection<String> channels = channelsFor(backing, channel);
+
+            @Override
+            public Collection<String> getChannels() {
+                return channels;
+            }
 
             public boolean check(T t, World world, int x, int y, int z) {
                 return backing.check(t, world, x, y, z);
@@ -2811,7 +3041,8 @@ public class StructureUtility {
             @Override
             public BlocksToPlace getBlocksToPlace(T t, World world, int x, int y, int z, ItemStack trigger,
                     AutoPlaceEnvironment env) {
-                return backing.getBlocksToPlace(t, world, x, y, z, trigger, env);
+                return backing
+                        .getBlocksToPlace(t, world, x, y, z, ChannelDataAccessor.withChannel(trigger, channel), env);
             }
 
             @Deprecated
@@ -2835,8 +3066,21 @@ public class StructureUtility {
                     warnNoExplicitSubChannel(env.getActor());
                 return backing.survivalPlaceBlock(t, world, x, y, z, newTrigger, env);
             }
+
+            @Nullable
+            @Override
+            public List<String> getDescription(T context) {
+                return backing.getDescription(context);
+            }
         };
     }
+
+    private static <T> Collection<String> channelsFor(IStructureElement<T> backing, String channel) {
+        Set<String> channels = new LinkedHashSet<>();
+        channels.add(channel);
+        channels.addAll(backing.getChannels());
+        return Collections.unmodifiableSet(channels);
+    }
     // endregion
 
     /**

src/main/java/com/gtnewhorizon/structurelib/structure/SurvivalBuildStructureWalker.java

@@ -43,9 +43,10 @@ class SurvivalBuildStructureWalker<T> implements IStructureWalker<T> {
         env.offsetABC[2] = c;
         env.setSource(params.getSource());
         PlaceResult placeResult = element.survivalPlaceBlock(object, world, x, y, z, trigger, env);
-        if (placeResult != PlaceResult.SKIP && built == -1) built = 0;
+        if (placeResult != PlaceResult.SKIP && placeResult != PlaceResult.REJECT_CONTINUE && built == -1) built = 0;
         switch (placeResult) {
             case SKIP:
+            case REJECT_CONTINUE:
                 return true;
             case ACCEPT:
                 if (check) element.check(object, world, x, y, z);

src/main/java/com/gtnewhorizon/structurelib/util/InventoryUtility.java

@@ -1,17 +1,3 @@
-/**
- * Copyright (c) 2022, glee8e This file is part of StructureLib.
- * <p>
- * StructureLib is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General
- * Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any
- * later version.
- * <p>
- * StructureLib is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied
- * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
- * details.
- * <p>
- * You should have received a copy of the GNU Lesser General Public License along with Foobar; if not, write to the Free
- * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
- */
 package com.gtnewhorizon.structurelib.util;
 
 import java.util.Arrays;

src/main/java/com/gtnewhorizon/structurelib/util/ItemStackArrayIterable.java

@@ -1,41 +0,0 @@
-package com.gtnewhorizon.structurelib.util;
-
-import java.util.Iterator;
-
-import net.minecraft.item.ItemStack;
-
-public class ItemStackArrayIterable implements Iterable<ItemStack> {
-
-    private final ItemStack[] stacks;
-
-    public ItemStackArrayIterable(ItemStack[] stacks) {
-        this.stacks = stacks;
-    }
-
-    public ItemStack[] getStacks() {
-        return stacks;
-    }
-
-    @Override
-    public Iterator<ItemStack> iterator() {
-        return new Iterator<ItemStack>() {
-
-            private int ptr = 0;
-
-            @Override
-            public boolean hasNext() {
-                return ptr < stacks.length;
-            }
-
-            @Override
-            public ItemStack next() {
-                return stacks[ptr++];
-            }
-
-            @Override
-            public void remove() {
-                stacks[ptr - 1] = null;
-            }
-        };
-    }
-}

src/main/java/com/gtnewhorizon/structurelib/util/MiscUtils.java

@@ -11,7 +11,6 @@ public class MiscUtils {
 
     private MiscUtils() {}
 
-    @SuppressWarnings("unchecked")
     public static Set<String> getTagKeys(NBTTagCompound tag) {
         return tag.func_150296_c();
     }

src/main/java/com/gtnewhorizon/structurelib/util/Vec3Impl.java

@@ -141,8 +141,7 @@ public class Vec3Impl implements Comparable<Vec3Impl> {
     public boolean equals(Object o) {
         if (this == o) {
             return true;
-        } else if (o instanceof Vec3Impl) {
-            Vec3Impl vec3i = (Vec3Impl) o;
+        } else if (o instanceof Vec3Impl vec3i) {
             return val0 == vec3i.val0 && val1 == vec3i.val1 && val2 == vec3i.val2;
         }
         return false;

src/main/javadoc/overview.html

@@ -174,6 +174,37 @@ StructureLib API documentation.
     master channel.
 </p>
 
+<h3>Metadata-only channels</h3>
+
+<p>
+    A channel does not need to represent a block or an element in a structure shape. Structure definitions can declare
+    metadata-only channels for values such as a widget selection or a variable structure height. These declarations are
+    independent of <code>addElement</code> and do not require a fake block or a shape character.
+</p>
+
+<pre>
+IStructureDefinition.&lt;Controller&gt;builder()
+        .addChannel("height", 3, 100)
+        .addChannel("length", 4, 50)
+        .addChannel(IChannelDefinition.unbounded("widget"))
+        .addElement('A', ...)
+        .build();
+</pre>
+
+<p>
+    Channel values are still stored as integers in the trigger item's <code>channels</code> NBT compound. The
+    generic channel GUI has no active structure definition, so it edits integers and does not impose one
+    structure's range on every other structure using the same channel name. Structure-aware code reads values through
+    <code>IStructureDefinition#getChannelData</code>, which uses the definition's default when the subchannel is absent
+    and then applies that definition's local normalization policy.
+</p>
+
+<p>
+    Existing elements wrapped with <code>StructureUtility.withChannel</code> are discovered automatically. An explicit
+    channel declaration supplies its local range and normalization policy for that structure. The same channel name may
+    therefore use different ranges in different structure definitions.
+</p>
+
 <h3>why is this called channel?</h3>
 
 Just give me a better name and I'd do the renaming.

src/main/resources/assets/structurelib/lang/en_US.lang

@@ -37,13 +37,20 @@ item.structurelib.constructableTrigger.gui.add=Add
 item.structurelib.constructableTrigger.gui.set=Update
 item.structurelib.constructableTrigger.gui.unset=Remove
 item.structurelib.constructableTrigger.gui.wipe=§4Clear
+item.structurelib.constructableTrigger.gui.wipe.confirm=§4Sure?
 item.structurelib.constructableTrigger.gui.channels.from=§rMod: §9§o%s
 item.structurelib.constructableTrigger.gui.info=Many multiblocks support some degree of variation in their structure and a sub channel allows indication of which variant to use.\n All sub channels have a sequence of lowercase characters as key and a positive integer as value. Most known sub channels should be available as typeahead completions.\n You can also drag and drop items from NEI to set the corresponding sub channel value. These items all have a tooltip of "§oIndicates§r §ovalue§r §oX§r §ofor§r §osub§r §ochannel§r §oY§r".
 
+item.structurelib.debugConstructableTrigger.name=Debug Multiblock Structure Hologram Projector
+
 channels.structurelib.show_errors=When set, will highlight parts of the multiblock that is definitely wrong
 
-structurelib.tooltip.channelvalue=§7Indicates value §6%d§r§7 for sub channel §6%s
-structurelib.tooltip.indicator_dnd=Drop into GUI to select this value for this channel
+structurelib.tooltip.channelvalue=§7Value §b%d§r§7 for subchannel §b%s
+structurelib.tooltip.indicator_dnd=Drop into GUI or middle-click to select this value for this channel
+structurelib.pickchannel.success=§aSet §b%s§r§a to §b%d§r
+structurelib.pickchannel.cleared=§aAll channels cleared§r
+structurelib.pickchannel.confirmwipe=§6Sneak+Middle-click again to clear all channels
+structurelib.pickchannel.nomapping=§cNo channel mapping found for this item
 
 structurelib.autoplace.built_stat=Built %s blocks
 structurelib.autoplace.complete=§aThis multiblock has completed!
@@ -51,6 +58,7 @@ structurelib.autoplace.error.not_enabled=§cThis multiblock does not support aut
 structurelib.autoplace.error.no_simple_block=§cSuggested to place §r%s§c but none was found
 structurelib.autoplace.error.no_item_stack=§cSuggested to place block by using §r%s§c but none was found
 structurelib.autoplace.warning.no_explicit_channel=§6This structure depends on nonexistent sub channel §r%s§6. Using master channel instead.
+structurelib.autoplace.missing_block=§cMissing block: %s
 
 structurelib.blockhint.desc.0=Helps while building
 structurelib.blockhint.0.name=Hint 1 dot

src/main/resources/assets/structurelib/lang/ru_RU.lang

@@ -0,0 +1,200 @@
+tile.structurelib.blockhint.name=Подсказка
+tile.structurelib.blockhint.0.name=Подсказка 1 точка
+tile.structurelib.blockhint.1.name=Подсказка 2 точки
+tile.structurelib.blockhint.2.name=Подсказка 3 точки
+tile.structurelib.blockhint.3.name=Подсказка 4 точки
+tile.structurelib.blockhint.4.name=Подсказка 5 точек
+tile.structurelib.blockhint.5.name=Подсказка 6 точек
+tile.structurelib.blockhint.6.name=Подсказка 7 точек
+tile.structurelib.blockhint.7.name=Подсказка 8 точек
+tile.structurelib.blockhint.8.name=Подсказка 9 точек
+tile.structurelib.blockhint.9.name=Подсказка 10 точек
+tile.structurelib.blockhint.10.name=Подсказка 11 точек
+tile.structurelib.blockhint.11.name=Подсказка 12 точек
+tile.structurelib.blockhint.12.name=Общая подсказка
+tile.structurelib.blockhint.13.name=Подсказка воздух
+tile.structurelib.blockhint.14.name=Подсказка нет воздуха
+tile.structurelib.blockhint.15.name=Подсказка ошибка
+
+item.structurelib.frontRotationTool.name=Инструмент для поворота (Автономный)
+item.structurelib.frontRotationTool.desc.0=Открывает интерфейс поворота лицевой стороны
+item.structurelib.frontRotationTool.desc.1=Поворачивает только лицевую сторону,
+item.structurelib.frontRotationTool.desc.2=что позволяет повернуть всю структуру.
+
+item.structurelib.constructableTrigger.name=Голограммный проектор мультиблоковой структуры
+item.structurelib.constructableTrigger.desc.0=Используется по интерфейсу контроллера
+item.structurelib.constructableTrigger.desc.1=Показывает схему постройки мультиблочной структуры,
+item.structurelib.constructableTrigger.desc.2=используется при нажатии по контроллеру
+item.structurelib.constructableTrigger.desc.3=(Shift+ПКМ для автоматической постройки)
+item.structurelib.constructableTrigger.desc.4=Количество проекторов в одном слоте влияет на тир/режим/тип постройки, если он не задан в GUI проектора
+item.structurelib.constructableTrigger.desc.5=Удерживайте §l[LSHIFT]§r для отображения данных канала
+item.structurelib.constructableTrigger.desc.lshift.0=Содержит %d подканал
+item.structurelib.constructableTrigger.too_fast=Подождите %d миллисекунд перед очередным автозаполнением...
+item.structurelib.constructableTrigger.gui.title=Подканалы
+item.structurelib.constructableTrigger.gui.key=Ключ:
+item.structurelib.constructableTrigger.gui.value=Значение:
+item.structurelib.constructableTrigger.gui.add=Добавить
+item.structurelib.constructableTrigger.gui.set=Обновить
+item.structurelib.constructableTrigger.gui.unset=Удалить
+item.structurelib.constructableTrigger.gui.wipe=§4Очистить
+item.structurelib.constructableTrigger.gui.wipe.confirm=§4Уверен?
+item.structurelib.constructableTrigger.gui.channels.from=§rМод: §9§o%s
+item.structurelib.constructableTrigger.gui.info=Многие мультиблоки поддерживают различные вариации структуры. Субканал позволяет указать, какой именно вариант использовать.\nВсе субканалы в качестве ключа используют строку из строчных букв, а в качестве значения - положительное целое число. Для большинства известных субканалов доступно автодополнение при вводе.\nВы также можете перетаскивать предметы из NEI, чтобы задать значение соответствующего субканала. Все эти предметы имеют подсказку: "§oЗадаёт§r §oзначение§r §oX§r §oдля§r §oсубканала§r §oY§r"
+
+channels.structurelib.show_errors=Если включено, подсвечивает элементы мультиблока с явными ошибками
+
+structurelib.tooltip.channelvalue=§7Указывает значение §b%d§r§7 для подканала §b%s
+structurelib.tooltip.indicator_dnd=Перейдите в GUI, чтобы выбрать это значение для этого канала.
+
+structurelib.autoplace.built_stat=Построено %s блоков
+structurelib.autoplace.complete=§aЭтот мультиблок собран!
+structurelib.autoplace.error.not_enabled=§cЭтот мультиблок не поддерживает автозаполнение в выживании!
+structurelib.autoplace.error.no_simple_block=§cПредлагалось разместить §r%s§c но ничего не нашлось
+structurelib.autoplace.error.no_item_stack=§cПредлагалось разместить блок используя §r%s§c но ничего не нашлось
+structurelib.autoplace.warning.no_explicit_channel=§6Эта структура зависит от несуществующего подканала §r%s§6. Вместо этого используйте главный канал.
+
+structurelib.blockhint.desc.0=Помогает при постройке
+structurelib.blockhint.0.name=Подсказка 1 точка
+structurelib.blockhint.1.name=Подсказка 2 точки
+structurelib.blockhint.2.name=Подсказка 3 точки
+structurelib.blockhint.3.name=Подсказка 4 точки
+structurelib.blockhint.4.name=Подсказка 5 точек
+structurelib.blockhint.5.name=Подсказка 6 точек
+structurelib.blockhint.6.name=Подсказка 7 точек
+structurelib.blockhint.7.name=Подсказка 8 точек
+structurelib.blockhint.8.name=Подсказка 9 точек
+structurelib.blockhint.9.name=Подсказка 10 точек
+structurelib.blockhint.10.name=Подсказка 11 точек
+structurelib.blockhint.11.name=Подсказка 12 точек
+structurelib.blockhint.desc.1=Заполнитель конкретной группы.
+structurelib.blockhint.12.name=Общая подсказка
+structurelib.blockhint.desc.2=Общий заполнитель.
+structurelib.blockhint.13.name=Подсказка воздух
+structurelib.blockhint.desc.3=Убедитесь, что это содержит воздух.
+structurelib.blockhint.14.name=Подсказка нет воздуха
+structurelib.blockhint.desc.4=Убедитесь, что это не содержит воздух.
+structurelib.blockhint.15.name=Подсказка ошибка
+structurelib.blockhint.desc.5=ОШИБКА (а что вы ожидали?)
+itemGroup.structurelib=StructureLib
+
+structurelib.facing.0=вниз нормальный нет
+structurelib.facing.1=вниз нормальный по горизонтали
+structurelib.facing.2=вниз нормальный по вертикали
+structurelib.facing.3=вниз нормальный оба
+structurelib.facing.4=вниз по часовой стрелке нет
+structurelib.facing.5=вниз по часовой стрелке по горизонтали
+structurelib.facing.6=вниз по часовой стрелке по вертикали
+structurelib.facing.7=вниз по часовой стрелке оба
+structurelib.facing.8=вниз перевернутый
+structurelib.facing.9=вниз перевернутый
+structurelib.facing.10=вниз перевернутый
+structurelib.facing.11=вниз перевернутый
+structurelib.facing.12=вниз против часовой стрелки
+structurelib.facing.13=вниз против часовой стрелки
+structurelib.facing.14=вниз против часовой стрелки
+structurelib.facing.15=вниз против часовой стрелки
+structurelib.facing.16=вверх нормальный нет
+structurelib.facing.17=вверх нормальный по горизонтали
+structurelib.facing.18=вверх нормальный по вертикали
+structurelib.facing.19=вверх нормальный оба
+structurelib.facing.20=вверх по часовой стрелке нет
+structurelib.facing.21=вверх по часовой стрелке по горизонтали
+structurelib.facing.22=вверх по часовой стрелке по вертикали
+structurelib.facing.23=вверх по часовой стрелке оба
+structurelib.facing.24=вверх перевернутый
+structurelib.facing.25=вверх перевернутый
+structurelib.facing.26=вверх перевернутый
+structurelib.facing.27=вверх перевернутый
+structurelib.facing.28=вверх против часовой стрелки
+structurelib.facing.29=вверх против часовой стрелки
+structurelib.facing.30=вверх против часовой стрелки
+structurelib.facing.31=вверх против часовой стрелки
+structurelib.facing.32=север нормальный нет
+structurelib.facing.33=север нормальный по горизонтали
+structurelib.facing.34=север нормальный по вертикали
+structurelib.facing.35=север нормальный оба
+structurelib.facing.36=север по часовой стрелке нет
+structurelib.facing.37=север по часовой стрелке по горизонтали
+structurelib.facing.38=север по часовой стрелке по вертикали
+structurelib.facing.39=север по часовой стрелке оба
+structurelib.facing.40=север перевернутый
+structurelib.facing.41=север перевернутый
+structurelib.facing.42=север перевернутый
+structurelib.facing.43=север перевернутый
+structurelib.facing.44=север против часовой стрелки
+structurelib.facing.45=север против часовой стрелки
+structurelib.facing.46=север против часовой стрелки
+structurelib.facing.47=север против часовой стрелки
+structurelib.facing.48=юг нормальный нет
+structurelib.facing.49=юг нормальный по горизонтали
+structurelib.facing.50=юг нормальный по вертикали
+structurelib.facing.51=юг нормальный оба
+structurelib.facing.52=юг по часовой стрелке нет
+structurelib.facing.53=юг по часовой стрелке по горизонтали
+structurelib.facing.54=юг по часовой стрелке по вертикали
+structurelib.facing.55=юг по часовой стрелке оба
+structurelib.facing.56=юг перевернутый
+structurelib.facing.57=юг перевернутый
+structurelib.facing.58=юг перевернутый
+structurelib.facing.59=юг перевернутый
+structurelib.facing.60=юг против часовой стрелки
+structurelib.facing.61=юг против часовой стрелки
+structurelib.facing.62=юг против часовой стрелки
+structurelib.facing.63=юг против часовой стрелки
+structurelib.facing.64=запад нормальный нет
+structurelib.facing.65=запад нормальный по горизонтали
+structurelib.facing.66=запад нормальный по вертикали
+structurelib.facing.67=запад нормальный оба
+structurelib.facing.68=запад по часовой стрелке нет
+structurelib.facing.69=запад по часовой стрелке по горизонтали
+structurelib.facing.70=запад по часовой стрелке по вертикали
+structurelib.facing.71=запад по часовой стрелке оба
+structurelib.facing.72=запад перевернутый
+structurelib.facing.73=запад перевернутый
+structurelib.facing.74=запад перевернутый
+structurelib.facing.75=запад перевернутый
+structurelib.facing.76=запад против часовой стрелки
+structurelib.facing.77=запад против часовой стрелки
+structurelib.facing.78=запад против часовой стрелки
+structurelib.facing.79=запад против часовой стрелки
+structurelib.facing.80=восток нормальный нет
+structurelib.facing.81=восток нормальный по горизонтали
+structurelib.facing.82=восток нормальный по вертикали
+structurelib.facing.83=восток нормальный оба
+structurelib.facing.84=восток по часовой стрелке нет
+structurelib.facing.85=восток по часовой стрелке по горизонтали
+structurelib.facing.86=восток по часовой стрелке по вертикали
+structurelib.facing.87=восток по часовой стрелке оба
+structurelib.facing.88=восток перевернутый
+structurelib.facing.89=восток перевернутый
+structurelib.facing.90=восток перевернутый
+structurelib.facing.91=восток перевернутый
+structurelib.facing.92=восток против часовой стрелки
+structurelib.facing.93=восток против часовой стрелки
+structurelib.facing.94=восток против часовой стрелки
+structurelib.facing.95=восток против часовой стрелки
+
+structurelib.config.client=Настройки клиента
+structurelib.config.client.tooltip=Настройки, которые изменяют только внешний вид игры, но не то, как она функционирует.
+structurelib.config.client.hologram=Голограммные настройки
+structurelib.config.client.hologram.tooltip=Настройки, которые по умолчанию меняют способ проецирования голограммы в мир.
+structurelib.config.client.hologram.maxCoexisting=Макс. сосуществующих голограмм
+structurelib.config.client.hologram.maxCoexisting.tooltip=Количество голограмм, которые могут сосуществовать. Обычно все подсказки, сгенерированные одним щелчком ПКМ, принадлежат одной голограмме. Будет предпринята попытка удаления старой голограммы, когда будет проецироваться новая голограмма и этот лимит будет превышен.
+structurelib.config.client.hologram.removeColliding=Удалить сталкивающиеся голограммы
+structurelib.config.client.hologram.removeColliding.tooltip=Whether an attempt will be made to remove any existing hologram that collides with a new hologram.
+
+structurelib.config.registries=Sorted Registries
+structurelib.config.registries.tooltip=Sorted Registry is how StructureLib internally keep track of certain features. Each individual elements may be reordered, disabled and enabled at user's command. Changes will be synced to server if needed.\nThis gui can also be accessed in game by shift right clicking air with Multiblock Structure Hologram Projector.
+structurelib.config.registries.stackextractors=Stack Extractors
+structurelib.config.registries.stackextractors.tooltip=Controls which inventory-from-stack functions are enabled during survival autoplace
+structurelib.config.registries.inventoryproviders=Источники инвентарей
+structurelib.config.registries.inventoryproviders.tooltip=Controls which inventories functions are enabled during survival autoplace
+
+structurelib.configgui.enabled=Включённый элемент
+structurelib.configgui.disabled=Отключённый элемент
+structurelib.configgui.drag.tooltip=Перетащите эту кнопку, чтобы изменить порядок этого элемента.
+
+structurelib.sortedregistry.inventoryproviders.5000-main-inventory=Основной инвентарь игрока
+structurelib.sortedregistry.inventoryproviders.5000-main-inventory.tooltip=36 ячеек для предметов в вашем основном инвентаре. Слоты для брони исключены.
+structurelib.sortedregistry.inventoryproviders.7000-ender-inventory=Инвентарь сундука Эндера
+structurelib.sortedregistry.inventoryproviders.7000-ender-inventory.tooltip=Соединяет на ваш инвентарь из ванильного сундука Эндера. Требуется не менее один "похожий на рюкзак Эндера" предмет в основном инвентаре для работы.

src/main/resources/assets/structurelib/lang/zh_CN.lang

@@ -42,7 +42,7 @@ item.structurelib.constructableTrigger.gui.info=许多多方块的结构都是
 
 channels.structurelib.show_errors=添加后，在投影时会高亮标出必然错误的部分
 
-structurelib.tooltip.channelvalue=§7表示子信道 §6%2$s§r§7 为 §6%d§r
+structurelib.tooltip.channelvalue=§7表示子信道 §b%2$s§r§7 为 §b%d§r
 structurelib.tooltip.indicator_dnd=拖入GUI中来选择该值
 
 structurelib.autoplace.built_stat=已放置 %s 个方块