Introduce custom loader additions to the model data generators. (#7450)

Currently implemented loaders:
* OBJ
* Composite
* Multi-layer
* Item layers (vanilla item/generated but with fullbright texture support)
* Bucket
* Separate Perspective

src/main/java/net/minecraftforge/client/model/SeparatePerspectiveModel.java

@@ -19,6 +19,7 @@
 
 package net.minecraftforge.client.model;
 
+import com.google.common.collect.ImmutableBiMap;
 import com.google.common.collect.ImmutableMap;
 import com.google.common.collect.Maps;
 import com.google.common.collect.Sets;
@@ -164,7 +165,7 @@ public class SeparatePerspectiveModel implements IModelGeometry<SeparatePerspect
     {
         public static final Loader INSTANCE = new Loader();
 
-        private static final ImmutableMap<String, ItemCameraTransforms.TransformType> PERSPECTIVES = ImmutableMap.<String, ItemCameraTransforms.TransformType>builder()
+        public static final ImmutableBiMap<String, ItemCameraTransforms.TransformType> PERSPECTIVES = ImmutableBiMap.<String, ItemCameraTransforms.TransformType>builder()
                 .put("none", ItemCameraTransforms.TransformType.NONE)
                 .put("third_person_left_hand", ItemCameraTransforms.TransformType.THIRD_PERSON_LEFT_HAND)
                 .put("third_person_right_hand", ItemCameraTransforms.TransformType.THIRD_PERSON_RIGHT_HAND)

src/main/java/net/minecraftforge/client/model/generators/CustomLoaderBuilder.java

@@ -0,0 +1,55 @@
+package net.minecraftforge.client.model.generators;
+
+import com.google.common.base.Preconditions;
+import com.google.gson.JsonObject;
+import net.minecraft.util.ResourceLocation;
+import net.minecraftforge.common.data.ExistingFileHelper;
+
+import java.util.LinkedHashMap;
+import java.util.Map;
+
+public abstract class CustomLoaderBuilder<T extends ModelBuilder<T>>
+{
+    protected final ResourceLocation loaderId;
+    protected final T parent;
+    protected final ExistingFileHelper existingFileHelper;
+    protected final Map<String, Boolean> visibility = new LinkedHashMap<>();
+
+    protected CustomLoaderBuilder(ResourceLocation loaderId, T parent, ExistingFileHelper existingFileHelper)
+    {
+        this.loaderId = loaderId;
+        this.parent = parent;
+        this.existingFileHelper = existingFileHelper;
+    }
+
+    public CustomLoaderBuilder<T> visibility(String partName, boolean show)
+    {
+        Preconditions.checkNotNull(partName, "partName must not be null");
+        this.visibility.put(partName, show);
+        return this;
+    }
+
+    public T end()
+    {
+        return parent;
+    }
+
+    public JsonObject toJson(JsonObject json)
+    {
+        json.addProperty("loader", loaderId.toString());
+
+        if (visibility.size() > 0)
+        {
+            JsonObject visibilityObj = new JsonObject();
+
+            for(Map.Entry<String, Boolean> entry : visibility.entrySet())
+            {
+                visibilityObj.addProperty(entry.getKey(), entry.getValue());
+            }
+
+            json.add("visibility", visibilityObj);
+        }
+
+        return json;
+    }
+}

src/main/java/net/minecraftforge/client/model/generators/ModelBuilder.java

@@ -19,13 +19,10 @@
 
 package net.minecraftforge.client.model.generators;
 
-import java.util.ArrayList;
-import java.util.Arrays;
-import java.util.LinkedHashMap;
-import java.util.List;
-import java.util.Map;
+import java.util.*;
 import java.util.Map.Entry;
 import java.util.function.BiConsumer;
+import java.util.function.BiFunction;
 import java.util.stream.Collectors;
 
 import javax.annotation.Nullable;
@@ -75,6 +72,8 @@ public class ModelBuilder<T extends ModelBuilder<T>> extends ModelFile {
 
     protected final List<ElementBuilder> elements = new ArrayList<>();
 
+    protected CustomLoaderBuilder customLoader = null;
+
     protected ModelBuilder(ResourceLocation outputLocation, ExistingFileHelper existingFileHelper) {
         super(outputLocation);
         this.existingFileHelper = existingFileHelper;
@@ -178,6 +177,7 @@ public class ModelBuilder<T extends ModelBuilder<T>> extends ModelFile {
     }
 
     public ElementBuilder element() {
+        Preconditions.checkState(customLoader == null, "Cannot use elements and custom loaders at the same time");
         ElementBuilder ret = new ElementBuilder();
         elements.add(ret);
         return ret;
@@ -191,13 +191,29 @@ public class ModelBuilder<T extends ModelBuilder<T>> extends ModelFile {
      * @throws IndexOutOfBoundsException if {@code} index is out of bounds
      */
     public ElementBuilder element(int index) {
+        Preconditions.checkState(customLoader == null, "Cannot use elements and custom loaders at the same time");
         Preconditions.checkElementIndex(index, elements.size(), "Element index");
         return elements.get(index);
     }
 
+    /**
+     * Use a custom loader instead of the vanilla elements.
+     * @param customLoaderFactory
+     * @return the custom loader builder
+     */
+    public <L extends CustomLoaderBuilder<T>> L customLoader(BiFunction<T, ExistingFileHelper, L> customLoaderFactory)
+    {
+        Preconditions.checkState(elements.size() == 0, "Cannot use elements and custom loaders at the same time");
+        Preconditions.checkNotNull(customLoaderFactory, "customLoaderFactory must not be null");
+        L customLoader  = customLoaderFactory.apply(self(), existingFileHelper);
+        this.customLoader = customLoader;
+        return customLoader;
+    }
+
     @VisibleForTesting
     public JsonObject toJson() {
         JsonObject root = new JsonObject();
+
         if (this.parent != null) {
             root.addProperty("parent", this.parent.getLocation().toString());
         }
@@ -290,6 +306,9 @@ public class ModelBuilder<T extends ModelBuilder<T>> extends ModelFile {
             root.add("elements", elements);
         }
 
+        if (customLoader != null)
+            return customLoader.toJson(root);
+
         return root;
     }
 

src/main/java/net/minecraftforge/client/model/generators/ModelProvider.java

@@ -35,6 +35,7 @@ import com.google.gson.GsonBuilder;
 import net.minecraft.data.DataGenerator;
 import net.minecraft.data.DirectoryCache;
 import net.minecraft.data.IDataProvider;
+import net.minecraft.resources.IResource;
 import net.minecraft.resources.ResourcePackType;
 import net.minecraft.util.ResourceLocation;
 import net.minecraftforge.common.data.ExistingFileHelper;
@@ -51,12 +52,39 @@ public abstract class ModelProvider<T extends ModelBuilder<T>> implements IDataP
         }
 
         @Override
-        public boolean exists(ResourceLocation loc, ResourcePackType type, String pathSuffix, String pathPrefix) {
-            if (generatedModels.containsKey(loc)) {
-                return true;
+        public boolean exists(ResourceLocation loc, ResourcePackType type, String pathSuffix, String pathPrefix)
+        {
+            if (pathPrefix.equals("models") && pathSuffix.equals(".json"))
+            {
+                if (generatedModels.containsKey(loc))
+                {
+                    return true;
+                }
             }
             return delegate.exists(loc, type, pathSuffix, pathPrefix);
         }
+
+        @Override
+        public boolean exists(ResourceLocation loc, ResourcePackType type) {
+            if (loc.getPath().startsWith("models/") && loc.getPath().endsWith(".json"))
+            {
+                ResourceLocation modelLoc = new ResourceLocation(
+                        loc.getNamespace(),
+                        loc.getPath().substring("models/".length(), loc.getPath().length() - ".json".length())
+                );
+                if (generatedModels.containsKey(modelLoc))
+                {
+                    return true;
+                }
+            }
+            return delegate.exists(loc, type);
+        }
+
+        @Override
+        public IResource getResource(ResourceLocation loc, ResourcePackType type) throws IOException
+        {
+            return delegate.getResource(loc, type);
+        }
     }
 
     public static final String BLOCK_FOLDER = "block";
@@ -357,6 +385,14 @@ public abstract class ModelProvider<T extends ModelBuilder<T>> implements IDataP
         return singleTexture(name, BLOCK_FOLDER + "/carpet", "wool", wool);
     }
 
+    /**
+     * Gets a model builder that's not directly saved to disk. Meant for use in custom model loaders.
+     */
+    public T nested()
+    {
+        return factory.apply(new ResourceLocation("dummy:dummy"));
+    }
+
     public ModelFile.ExistingModelFile getExistingFile(ResourceLocation path) {
         ModelFile.ExistingModelFile ret = new ModelFile.ExistingModelFile(extendWithFolder(path), existingFileHelper);
         ret.assertExistence();

src/main/java/net/minecraftforge/client/model/generators/loaders/CompositeModelBuilder.java

@@ -0,0 +1,50 @@
+package net.minecraftforge.client.model.generators.loaders;
+
+import com.google.common.base.Preconditions;
+import com.google.gson.JsonObject;
+import net.minecraft.fluid.Fluid;
+import net.minecraft.util.ResourceLocation;
+import net.minecraftforge.client.model.generators.CustomLoaderBuilder;
+import net.minecraftforge.client.model.generators.ModelBuilder;
+import net.minecraftforge.common.data.ExistingFileHelper;
+
+import java.util.LinkedHashMap;
+import java.util.Map;
+
+public class CompositeModelBuilder<T extends ModelBuilder<T>> extends CustomLoaderBuilder<T>
+{
+    public static <T extends ModelBuilder<T>> CompositeModelBuilder<T> begin(T parent, ExistingFileHelper existingFileHelper)
+    {
+        return new CompositeModelBuilder<>(parent, existingFileHelper);
+    }
+
+    private final Map<String, T> childModels = new LinkedHashMap<>();
+
+    protected CompositeModelBuilder(T parent, ExistingFileHelper existingFileHelper)
+    {
+        super(new ResourceLocation("forge:composite"), parent, existingFileHelper);
+    }
+
+    public CompositeModelBuilder<T> submodel(String name, T modelBuilder)
+    {
+        Preconditions.checkNotNull(name, "name must not be null");
+        Preconditions.checkNotNull(modelBuilder, "modelBuilder must not be null");
+        childModels.put(name, modelBuilder);
+        return this;
+    }
+
+    @Override
+    public JsonObject toJson(JsonObject json)
+    {
+        json = super.toJson(json);
+
+        JsonObject parts = new JsonObject();
+        for(Map.Entry<String, T> entry : childModels.entrySet())
+        {
+            parts.add(entry.getKey(), entry.getValue().toJson());
+        }
+        json.add("parts", parts);
+
+        return json;
+    }
+}

src/main/java/net/minecraftforge/client/model/generators/loaders/DynamicBucketModelBuilder.java

@@ -0,0 +1,83 @@
+package net.minecraftforge.client.model.generators.loaders;
+
+import com.google.common.base.Preconditions;
+import com.google.gson.JsonObject;
+import net.minecraft.fluid.Fluid;
+import net.minecraft.util.ResourceLocation;
+import net.minecraftforge.client.model.generators.CustomLoaderBuilder;
+import net.minecraftforge.client.model.generators.ModelBuilder;
+import net.minecraftforge.common.data.ExistingFileHelper;
+
+public class DynamicBucketModelBuilder<T extends ModelBuilder<T>> extends CustomLoaderBuilder<T>
+{
+    public static <T extends ModelBuilder<T>> DynamicBucketModelBuilder<T> begin(T parent, ExistingFileHelper existingFileHelper)
+    {
+        return new DynamicBucketModelBuilder<>(parent, existingFileHelper);
+    }
+
+    private ResourceLocation fluid;
+    private Boolean flipGas;
+    private Boolean applyTint;
+    private Boolean coverIsMask;
+    private Boolean applyFluidLuminosity;
+
+    protected DynamicBucketModelBuilder(T parent, ExistingFileHelper existingFileHelper)
+    {
+        super(new ResourceLocation("forge:bucket"), parent, existingFileHelper);
+    }
+
+    public DynamicBucketModelBuilder<T> fluid(Fluid fluid)
+    {
+        Preconditions.checkNotNull(fluid, "fluid must not be null");
+        this.fluid = fluid.getRegistryName();
+        return this;
+    }
+
+    public DynamicBucketModelBuilder<T> flipGas(boolean flip)
+    {
+        this.flipGas = flip;
+        return this;
+    }
+
+    public DynamicBucketModelBuilder<T> applyTint(boolean tint)
+    {
+        this.applyTint = tint;
+        return this;
+    }
+
+    public DynamicBucketModelBuilder<T> coverIsMask(boolean coverIsMask)
+    {
+        this.coverIsMask = coverIsMask;
+        return this;
+    }
+
+    public DynamicBucketModelBuilder<T> applyFluidLuminosity(boolean applyFluidLuminosity)
+    {
+        this.applyFluidLuminosity = applyFluidLuminosity;
+        return this;
+    }
+
+    @Override
+    public JsonObject toJson(JsonObject json)
+    {
+        json = super.toJson(json);
+
+        Preconditions.checkNotNull(fluid, "fluid must not be null");
+
+        json.addProperty("fluid", fluid.toString());
+
+        if (flipGas != null)
+            json.addProperty("flipGas", flipGas);
+
+        if (applyTint != null)
+            json.addProperty("applyTint", applyTint);
+
+        if (coverIsMask != null)
+            json.addProperty("coverIsMask", coverIsMask);
+
+        if (applyFluidLuminosity != null)
+            json.addProperty("applyFluidLuminosity", applyFluidLuminosity);
+
+        return json;
+    }
+}

src/main/java/net/minecraftforge/client/model/generators/loaders/ItemLayersModelBuilder.java

@@ -0,0 +1,49 @@
+package net.minecraftforge.client.model.generators.loaders;
+
+import com.google.common.base.Preconditions;
+import com.google.gson.JsonArray;
+import com.google.gson.JsonObject;
+import net.minecraft.util.ResourceLocation;
+import net.minecraftforge.client.model.generators.CustomLoaderBuilder;
+import net.minecraftforge.client.model.generators.ModelBuilder;
+import net.minecraftforge.common.data.ExistingFileHelper;
+
+import java.util.LinkedHashSet;
+import java.util.Set;
+
+public class ItemLayersModelBuilder<T extends ModelBuilder<T>> extends CustomLoaderBuilder<T>
+{
+    public static <T extends ModelBuilder<T>> ItemLayersModelBuilder<T> begin(T parent, ExistingFileHelper existingFileHelper)
+    {
+        return new ItemLayersModelBuilder<>(parent, existingFileHelper);
+    }
+
+    private final Set<Integer> fullbright = new LinkedHashSet<>();
+
+    protected ItemLayersModelBuilder(T parent, ExistingFileHelper existingFileHelper)
+    {
+        super(new ResourceLocation("forge:item-layers"), parent, existingFileHelper);
+    }
+
+    public ItemLayersModelBuilder<T> fullbright(int layer)
+    {
+        Preconditions.checkArgument(layer >= 0, "layer must be >= 0");
+        fullbright.add(layer);
+        return this;
+    }
+
+    @Override
+    public JsonObject toJson(JsonObject json)
+    {
+        json = super.toJson(json);
+
+        JsonArray parts = new JsonArray();
+        for(int entry : fullbright)
+        {
+            parts.add(entry);
+        }
+        json.add("fullbright_layers", parts);
+
+        return json;
+    }
+}

src/main/java/net/minecraftforge/client/model/generators/loaders/MultiLayerModelBuilder.java

@@ -0,0 +1,52 @@
+package net.minecraftforge.client.model.generators.loaders;
+
+import com.google.common.base.Preconditions;
+import com.google.gson.JsonObject;
+import net.minecraft.client.renderer.RenderType;
+import net.minecraft.util.ResourceLocation;
+import net.minecraftforge.client.model.MultiLayerModel;
+import net.minecraftforge.client.model.generators.CustomLoaderBuilder;
+import net.minecraftforge.client.model.generators.ModelBuilder;
+import net.minecraftforge.common.data.ExistingFileHelper;
+
+import java.util.LinkedHashMap;
+import java.util.Map;
+
+public class MultiLayerModelBuilder<T extends ModelBuilder<T>> extends CustomLoaderBuilder<T>
+{
+    public static <T extends ModelBuilder<T>> MultiLayerModelBuilder<T> begin(T parent, ExistingFileHelper existingFileHelper)
+    {
+        return new MultiLayerModelBuilder<>(parent, existingFileHelper);
+    }
+
+    private final Map<String, T> childModels = new LinkedHashMap<>();
+
+    protected MultiLayerModelBuilder(T parent, ExistingFileHelper existingFileHelper)
+    {
+        super(new ResourceLocation("forge:multi-layer"), parent, existingFileHelper);
+    }
+
+    public MultiLayerModelBuilder<T> submodel(RenderType layer, T modelBuilder)
+    {
+        Preconditions.checkNotNull(layer, "layer must not be null");
+        Preconditions.checkArgument(MultiLayerModel.Loader.BLOCK_LAYERS.containsValue(layer), "layer must be supported by MultiLayerModel");
+        Preconditions.checkNotNull(modelBuilder, "modelBuilder must not be null");
+        childModels.put(MultiLayerModel.Loader.BLOCK_LAYERS.inverse().get(layer), modelBuilder);
+        return this;
+    }
+
+    @Override
+    public JsonObject toJson(JsonObject json)
+    {
+        json = super.toJson(json);
+
+        JsonObject parts = new JsonObject();
+        for(Map.Entry<String, T> entry : childModels.entrySet())
+        {
+            parts.add(entry.getKey(), entry.getValue().toJson());
+        }
+        json.add("layers", parts);
+
+        return json;
+    }
+}

src/main/java/net/minecraftforge/client/model/generators/loaders/OBJLoaderBuilder.java

@@ -0,0 +1,98 @@
+package net.minecraftforge.client.model.generators.loaders;
+
+import com.google.common.base.Preconditions;
+import com.google.gson.JsonObject;
+import net.minecraft.resources.ResourcePackType;
+import net.minecraft.util.ResourceLocation;
+import net.minecraftforge.client.model.generators.CustomLoaderBuilder;
+import net.minecraftforge.client.model.generators.ModelBuilder;
+import net.minecraftforge.common.data.ExistingFileHelper;
+
+public class OBJLoaderBuilder<T extends ModelBuilder<T>> extends CustomLoaderBuilder<T>
+{
+    public static <T extends ModelBuilder<T>> OBJLoaderBuilder<T> begin(T parent, ExistingFileHelper existingFileHelper)
+    {
+        return new OBJLoaderBuilder<>(parent, existingFileHelper);
+    }
+
+    private ResourceLocation modelLocation;
+    private Boolean detectCullableFaces;
+    private Boolean diffuseLighting;
+    private Boolean flipV;
+    private Boolean ambientToFullbright;
+    private ResourceLocation materialLibraryOverrideLocation;
+
+    protected OBJLoaderBuilder(T parent, ExistingFileHelper existingFileHelper)
+    {
+        super(new ResourceLocation("forge:obj"), parent, existingFileHelper);
+    }
+
+    public OBJLoaderBuilder<T> modelLocation(ResourceLocation modelLocation)
+    {
+        Preconditions.checkNotNull(modelLocation, "modelLocation must not be null");
+        Preconditions.checkArgument(existingFileHelper.exists(modelLocation, ResourcePackType.CLIENT_RESOURCES),
+                "OBJ Model %s does not exist in any known resource pack", modelLocation);
+        this.modelLocation = modelLocation;
+        return this;
+    }
+
+    public OBJLoaderBuilder<T> detectCullableFaces(boolean detectCullableFaces)
+    {
+        this.detectCullableFaces = detectCullableFaces;
+        return this;
+    }
+
+    public OBJLoaderBuilder<T> diffuseLighting(boolean diffuseLighting)
+    {
+        this.diffuseLighting = diffuseLighting;
+        return this;
+    }
+
+    public OBJLoaderBuilder<T> flipV(boolean flipV)
+    {
+        this.flipV = flipV;
+        return this;
+    }
+
+    public OBJLoaderBuilder<T> ambientToFullbright(boolean ambientToFullbright)
+    {
+        this.ambientToFullbright = ambientToFullbright;
+        return this;
+    }
+
+    public OBJLoaderBuilder<T> overrideMaterialLibrary(ResourceLocation materialLibraryOverrideLocation)
+    {
+        Preconditions.checkNotNull(materialLibraryOverrideLocation, "materialLibraryOverrideLocation must not be null");
+        Preconditions.checkArgument(existingFileHelper.exists(materialLibraryOverrideLocation, ResourcePackType.CLIENT_RESOURCES),
+                "OBJ Model %s does not exist in any known resource pack", materialLibraryOverrideLocation);
+        this.materialLibraryOverrideLocation = materialLibraryOverrideLocation;
+        return this;
+    }
+
+    @Override
+    public JsonObject toJson(JsonObject json)
+    {
+        json = super.toJson(json);
+
+        Preconditions.checkNotNull(modelLocation, "modelLocation must not be null");
+
+        json.addProperty("model", modelLocation.toString());
+
+        if (detectCullableFaces != null)
+            json.addProperty("detectCullableFaces", detectCullableFaces);
+
+        if (diffuseLighting != null)
+            json.addProperty("diffuseLighting", diffuseLighting);
+
+        if (flipV != null)
+            json.addProperty("flip-v", flipV);
+
+        if (ambientToFullbright != null)
+            json.addProperty("ambientToFullbright", ambientToFullbright);
+
+        if (materialLibraryOverrideLocation != null)
+            json.addProperty("materialLibraryOverrideLocation", materialLibraryOverrideLocation.toString());
+
+        return json;
+    }
+}

src/main/java/net/minecraftforge/client/model/generators/loaders/SeparatePerspectiveModelBuilder.java

@@ -0,0 +1,66 @@
+package net.minecraftforge.client.model.generators.loaders;
+
+import com.google.common.base.Preconditions;
+import com.google.gson.JsonObject;
+import net.minecraft.client.renderer.model.ItemCameraTransforms;
+import net.minecraft.util.ResourceLocation;
+import net.minecraftforge.client.model.MultiLayerModel;
+import net.minecraftforge.client.model.SeparatePerspectiveModel;
+import net.minecraftforge.client.model.generators.CustomLoaderBuilder;
+import net.minecraftforge.client.model.generators.ModelBuilder;
+import net.minecraftforge.common.data.ExistingFileHelper;
+
+import java.util.LinkedHashMap;
+import java.util.Map;
+
+public class SeparatePerspectiveModelBuilder<T extends ModelBuilder<T>> extends CustomLoaderBuilder<T>
+{
+    public static <T extends ModelBuilder<T>> SeparatePerspectiveModelBuilder<T> begin(T parent, ExistingFileHelper existingFileHelper)
+    {
+        return new SeparatePerspectiveModelBuilder<>(parent, existingFileHelper);
+    }
+
+    private T base;
+    private final Map<String, T> childModels = new LinkedHashMap<>();
+
+    protected SeparatePerspectiveModelBuilder(T parent, ExistingFileHelper existingFileHelper)
+    {
+        super(new ResourceLocation("forge:separate-perspective"), parent, existingFileHelper);
+    }
+
+    public SeparatePerspectiveModelBuilder<T> base(T modelBuilder)
+    {
+        Preconditions.checkNotNull(modelBuilder, "modelBuilder must not be null");
+        base = modelBuilder;
+        return this;
+    }
+
+    public SeparatePerspectiveModelBuilder<T> perspective(ItemCameraTransforms.TransformType perspective, T modelBuilder)
+    {
+        Preconditions.checkNotNull(perspective, "layer must not be null");
+        Preconditions.checkArgument(SeparatePerspectiveModel.Loader.PERSPECTIVES.containsValue(perspective), "perspective is not included in SeparatePerspectiveModel. New mc version?");
+        Preconditions.checkNotNull(modelBuilder, "modelBuilder must not be null");
+        childModels.put(SeparatePerspectiveModel.Loader.PERSPECTIVES.inverse().get(perspective), modelBuilder);
+        return this;
+    }
+
+    @Override
+    public JsonObject toJson(JsonObject json)
+    {
+        json = super.toJson(json);
+
+        if (base != null)
+        {
+            json.add("base", base.toJson());
+        }
+
+        JsonObject parts = new JsonObject();
+        for(Map.Entry<String, T> entry : childModels.entrySet())
+        {
+            parts.add(entry.getKey(), entry.getValue().toJson());
+        }
+        json.add("perspectives", parts);
+
+        return json;
+    }
+}

src/main/java/net/minecraftforge/common/data/ExistingFileHelper.java

@@ -70,6 +70,22 @@ public class ExistingFileHelper {
         return new ResourceLocation(base.getNamespace(), prefix + "/" + base.getPath() + suffix);
     }
 
+    /**
+     * Check if a given resource exists in the known resource packs.
+     *
+     * @param loc        the base location of the resource, e.g.
+     *                   {@code "minecraft:block/stone"}
+     * @param type       the type of resources to check
+     * @return {@code true} if the resource exists in any pack, {@code false}
+     *         otherwise
+     */
+    public boolean exists(ResourceLocation loc, ResourcePackType type) {
+        if (!enable) {
+            return true;
+        }
+        return getManager(type).hasResource(loc);
+    }
+
     /**
      * Check if a given resource exists in the known resource packs.
      * 
@@ -83,15 +99,17 @@ public class ExistingFileHelper {
      *         otherwise
      */
     public boolean exists(ResourceLocation loc, ResourcePackType type, String pathSuffix, String pathPrefix) {
-        if (!enable) {
-            return true;
-        }
-        return getManager(type).hasResource(getLocation(loc, pathSuffix, pathPrefix));
+        return exists(getLocation(loc, pathSuffix, pathPrefix), type);
     }
 
     @VisibleForTesting
     public IResource getResource(ResourceLocation loc, ResourcePackType type, String pathSuffix, String pathPrefix) throws IOException {
-        return getManager(type).getResource(getLocation(loc, pathSuffix, pathPrefix));
+        return getResource(getLocation(loc, pathSuffix, pathPrefix), type);
+    }
+
+    @VisibleForTesting
+    public IResource getResource(ResourceLocation loc, ResourcePackType type) throws IOException {
+        return getManager(type).getResource(loc);
     }
 
     /**