Add GetCollisionBoxesEvent. Allows manipulation of the collision boxes for moving entities and entities stuck in walls. (#3397)

patches/minecraft/net/minecraft/entity/Entity.java.patch

@@ -109,6 +109,15 @@
              this.field_184239_as = null;
              entity.func_184225_p(this);
          }
+@@ -2182,7 +2201,7 @@
+         double d1 = p_145771_3_ - (double)blockpos.func_177956_o();
+         double d2 = p_145771_5_ - (double)blockpos.func_177952_p();
+         List<AxisAlignedBB> list = this.field_70170_p.func_147461_a(this.func_174813_aQ());
+-
++        net.minecraftforge.common.MinecraftForge.EVENT_BUS.post(new net.minecraftforge.event.world.GetCollisionBoxesEvent(this.field_70170_p, this, this.func_174813_aQ(), list));
+         if (list.isEmpty())
+         {
+             return false;
 @@ -2336,6 +2355,7 @@
      {
          if (!this.field_70170_p.field_72995_K && !this.field_70128_L)

patches/minecraft/net/minecraft/world/World.java.patch

@@ -206,6 +206,15 @@
              this.func_72964_e(i, j).func_76612_a(p_72838_1_);
              this.field_72996_f.add(p_72838_1_);
              this.func_72923_a(p_72838_1_);
+@@ -1221,7 +1284,7 @@
+                 }
+             }
+         }
+-
++        net.minecraftforge.common.MinecraftForge.EVENT_BUS.post(new net.minecraftforge.event.world.GetCollisionBoxesEvent(this, p_184144_1_, p_184144_2_, list));
+         return list;
+     }
+ 
 @@ -1296,7 +1359,6 @@
          return list;
      }

src/main/java/net/minecraftforge/event/world/GetCollisionBoxesEvent.java

@@ -0,0 +1,73 @@
+/*
+ * Minecraft Forge
+ * Copyright (c) 2016.
+ *
+ * This library 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 version 2.1
+ * of the License.
+ *
+ * This library 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.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+package net.minecraftforge.event.world;
+
+import net.minecraft.entity.Entity;
+import net.minecraft.util.math.AxisAlignedBB;
+import net.minecraft.world.World;
+import net.minecraftforge.common.MinecraftForge;
+import net.minecraftforge.fml.common.eventhandler.Cancelable;
+
+import javax.annotation.Nullable;
+import java.util.List;
+
+/**
+ * This event is fired after {@link Entity#pushOutOfBlocks(double, double, double)} calls {@link World#getCollisionBoxes(AxisAlignedBB)}
+ * and before returning the list in {@link World#getCollisionBoxes(Entity, AxisAlignedBB)}<br>
+ * <br>
+ * {@link #entity} contains the entity calling {@link Entity#pushOutOfBlocks(double, double, double)} or the entity passed in the {@link World#getCollisionBoxes(Entity, AxisAlignedBB)}. <b>Can be null.</b><br>
+ * {@link #aabb} contains the AxisAlignedBB passed in the method.<br>
+ * {@link #collisionBoxesList} contains the list of detected collision boxes intersecting with {@link #aabb}. The list can be modified.<br>
+ * <br>
+ * This event is not {@link Cancelable}.<br>
+ * <br>
+ * This event does not have a result. {@link HasResult} <br>
+ * <br>
+ * This event is fired on the {@link MinecraftForge#EVENT_BUS}.<br>
+ **/
+public class GetCollisionBoxesEvent extends WorldEvent
+{
+    private final Entity entity;
+    private final AxisAlignedBB aabb;
+    private final List<AxisAlignedBB> collisionBoxesList;
+
+    public GetCollisionBoxesEvent(World world, @Nullable Entity entity, AxisAlignedBB aabb, List<AxisAlignedBB> collisionBoxesList)
+    {
+        super(world);
+        this.entity = entity;
+        this.aabb = aabb;
+        this.collisionBoxesList = collisionBoxesList;
+    }
+
+    public Entity getEntity()
+    {
+        return entity;
+    }
+
+    public AxisAlignedBB getAabb()
+    {
+        return aabb;
+    }
+
+    public List<AxisAlignedBB> getCollisionBoxesList()
+    {
+        return collisionBoxesList;
+    }
+}