Add fast graphics render type to block model jsons (#10395)

Make modded leaves behave like vanilla leaves by default (Fixes #10389)

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

@@ -208,6 +208,7 @@ public class CompositeModel implements IUnbakedGeometry<CompositeModel> {
             private final ItemTransforms transforms;
             private TextureAtlasSprite particle;
             private RenderTypeGroup lastRenderTypes = RenderTypeGroup.EMPTY;
+            private RenderTypeGroup lastRenderTypesFast = RenderTypeGroup.EMPTY;
 
             private Builder(boolean isAmbientOcclusion, boolean isGui3d, boolean isSideLit, TextureAtlasSprite particle, ItemTransforms transforms) {
                 this.isAmbientOcclusion = isAmbientOcclusion;
@@ -218,23 +219,32 @@ public class CompositeModel implements IUnbakedGeometry<CompositeModel> {
             }
 
             public void addLayer(BakedModel model) {
-                flushQuads(null);
+                flushQuads(RenderTypeGroup.EMPTY, RenderTypeGroup.EMPTY);
                 children.add(model);
             }
 
             private void addLayer(RenderTypeGroup renderTypes, List<BakedQuad> quads) {
-                var modelBuilder = IModelBuilder.of(isAmbientOcclusion, isSideLit, isGui3d, transforms, particle, renderTypes);
+                this.addLayer(renderTypes, RenderTypeGroup.EMPTY, quads);
+            }
+
+            private void addLayer(RenderTypeGroup renderTypes, RenderTypeGroup renderTypesFast, List<BakedQuad> quads) {
+                var modelBuilder = IModelBuilder.of(isAmbientOcclusion, isSideLit, isGui3d, transforms, particle, renderTypes, renderTypesFast);
                 quads.forEach(modelBuilder::addUnculledFace);
                 children.add(modelBuilder.build());
             }
 
             private void flushQuads(RenderTypeGroup renderTypes) {
+                this.flushQuads(renderTypes, RenderTypeGroup.EMPTY);
+            }
+
+            private void flushQuads(RenderTypeGroup renderTypes, RenderTypeGroup renderTypesFast) {
                 if (!Objects.equals(renderTypes, lastRenderTypes)) {
                     if (!quads.isEmpty()) {
-                        addLayer(lastRenderTypes, quads);
+                        addLayer(lastRenderTypes, lastRenderTypesFast, quads);
                         quads.clear();
                     }
                     lastRenderTypes = renderTypes;
+                    lastRenderTypesFast = renderTypesFast;
                 }
             }
 
@@ -244,20 +254,28 @@ public class CompositeModel implements IUnbakedGeometry<CompositeModel> {
             }
 
             public Builder addQuads(RenderTypeGroup renderTypes, BakedQuad... quadsToAdd) {
-                flushQuads(renderTypes);
+                return this.addQuads(renderTypes, RenderTypeGroup.EMPTY, quadsToAdd);
+            }
+
+            public Builder addQuads(RenderTypeGroup renderTypes, RenderTypeGroup renderTypesFast, BakedQuad... quadsToAdd) {
+                flushQuads(renderTypes, renderTypesFast);
                 Collections.addAll(quads, quadsToAdd);
                 return this;
             }
 
             public Builder addQuads(RenderTypeGroup renderTypes, Collection<BakedQuad> quadsToAdd) {
-                flushQuads(renderTypes);
+                return this.addQuads(renderTypes, RenderTypeGroup.EMPTY, quadsToAdd);
+            }
+
+            public Builder addQuads(RenderTypeGroup renderTypes, RenderTypeGroup renderTypesFast, Collection<BakedQuad> quadsToAdd) {
+                flushQuads(renderTypes, renderTypesFast);
                 quads.addAll(quadsToAdd);
                 return this;
             }
 
             public BakedModel build() {
                 if (!quads.isEmpty()) {
-                    addLayer(lastRenderTypes, quads);
+                    addLayer(lastRenderTypes, lastRenderTypesFast, quads);
                 }
                 var childrenBuilder = ImmutableMap.<String, BakedModel>builder();
                 var itemPassesBuilder = ImmutableList.<BakedModel>builder();

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

@@ -50,7 +50,7 @@ public class EmptyModel extends SimpleUnbakedGeometry<EmptyModel> {
         private static final Material MISSING_TEXTURE = new Material(InventoryMenu.BLOCK_ATLAS, MissingTextureAtlasSprite.getLocation());
 
         public Baked() {
-            super(List.of(), Map.of(), false, false, false, UnitTextureAtlasSprite.INSTANCE, ItemTransforms.NO_TRANSFORMS, RenderTypeGroup.EMPTY);
+            super(List.of(), Map.of(), false, false, false, UnitTextureAtlasSprite.INSTANCE, ItemTransforms.NO_TRANSFORMS, RenderTypeGroup.EMPTY, RenderTypeGroup.EMPTY);
         }
 
         @Override

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

@@ -73,6 +73,12 @@ public class ExtendedBlockModelDeserializer extends BlockModel.Deserializer
             model.customData.setRenderTypeHint(ResourceLocation.parse(renderTypeHintName));
         }
 
+        if (jsonobject.has("render_type_fast"))
+        {
+            var renderTypeHintName = GsonHelper.getAsString(jsonobject, "render_type_fast");
+            model.customData.setRenderTypeFastHint(ResourceLocation.parse(renderTypeHintName));
+        }
+
         if (jsonobject.has("visibility"))
         {
             JsonObject visibility = GsonHelper.getAsJsonObject(jsonobject, "visibility");

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

@@ -32,6 +32,18 @@ public interface IModelBuilder<T extends IModelBuilder<T>> {
         return new Simple(hasAmbientOcclusion, usesBlockLight, isGui3d, transforms, particle, renderTypes);
     }
 
+    static IModelBuilder<?> of(
+        boolean hasAmbientOcclusion,
+        boolean usesBlockLight,
+        boolean isGui3d,
+        ItemTransforms transforms,
+        TextureAtlasSprite particle,
+        RenderTypeGroup renderTypes,
+        RenderTypeGroup renderTypesFast
+    ){
+        return new Simple(hasAmbientOcclusion, usesBlockLight, isGui3d, transforms, particle, renderTypes, renderTypesFast);
+    }
+
     /**
      * Creates a new model builder that collects quads to the provided list, returning
      * {@linkplain EmptyModel#BAKED an empty model} if you call {@link #build()}.
@@ -49,12 +61,20 @@ public interface IModelBuilder<T extends IModelBuilder<T>> {
     class Simple implements IModelBuilder<Simple> {
         private final SimpleBakedModel.Builder builder;
         private final RenderTypeGroup renderTypes;
+        private final RenderTypeGroup renderTypesFast;
 
         private Simple(boolean hasAmbientOcclusion, boolean usesBlockLight, boolean isGui3d,
                        ItemTransforms transforms, TextureAtlasSprite particle, RenderTypeGroup renderTypes
+        ) {
+            this(hasAmbientOcclusion, usesBlockLight, isGui3d, transforms, particle, renderTypes, RenderTypeGroup.EMPTY);
+        }
+
+        private Simple(boolean hasAmbientOcclusion, boolean usesBlockLight, boolean isGui3d,
+                       ItemTransforms transforms, TextureAtlasSprite particle, RenderTypeGroup renderTypes, RenderTypeGroup renderTypesFast
         ) {
             this.builder = new SimpleBakedModel.Builder(hasAmbientOcclusion, usesBlockLight, isGui3d, transforms).particle(particle);
             this.renderTypes = renderTypes;
+            this.renderTypesFast = renderTypesFast;
         }
 
         @Override

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

@@ -39,10 +39,16 @@ public class ItemLayerModel implements IUnbakedGeometry<ItemLayerModel> {
     @Nullable
     private ImmutableList<Material> textures;
     private final Int2ObjectMap<ResourceLocation> renderTypeNames;
+    private final Int2ObjectMap<ResourceLocation> renderTypeFastNames;
 
     private ItemLayerModel(@Nullable ImmutableList<Material> textures, Int2ObjectMap<ResourceLocation> renderTypeNames) {
+        this(textures, renderTypeNames, new Int2ObjectOpenHashMap<>());
+    }
+
+    private ItemLayerModel(@Nullable ImmutableList<Material> textures, Int2ObjectMap<ResourceLocation> renderTypeNames, Int2ObjectMap<ResourceLocation> renderTypeFastNames) {
         this.textures = textures;
         this.renderTypeNames = renderTypeNames;
+        this.renderTypeFastNames = renderTypeFastNames;
     }
 
     @Override
@@ -69,7 +75,9 @@ public class ItemLayerModel implements IUnbakedGeometry<ItemLayerModel> {
             var quads = UnbakedGeometryHelper.bakeElements(unbaked, $ -> sprite, modelState);
             var renderTypeName = renderTypeNames.get(i);
             var renderTypes = renderTypeName != null ? context.getRenderType(renderTypeName) : null;
-            builder.addQuads(renderTypes != null ? renderTypes : normalRenderTypes, quads);
+            var renderTypeFastName = renderTypeFastNames.get(i);
+            var renderTypesFast = renderTypeFastName != null ? context.getRenderType(renderTypeFastName) : null;
+            builder.addQuads(renderTypes != null ? renderTypes : normalRenderTypes, renderTypesFast != null ? renderTypesFast : RenderTypeGroup.EMPTY, quads);
         }
 
         return builder.build();
@@ -80,20 +88,27 @@ public class ItemLayerModel implements IUnbakedGeometry<ItemLayerModel> {
 
         @Override
         public ItemLayerModel read(JsonObject jsonObject, JsonDeserializationContext deserializationContext) {
+            var renderTypeNames = readRenderTypeNames(jsonObject, "render_types");
+            var renderTypeFastNames = readRenderTypeNames(jsonObject, "render_types_fast");
+            return new ItemLayerModel(null, renderTypeNames, renderTypeFastNames);
+        }
+
+        private static Int2ObjectMap<ResourceLocation> readRenderTypeNames(JsonObject jsonObject, String key) {
             var renderTypeNames = new Int2ObjectOpenHashMap<ResourceLocation>();
-            if (jsonObject.has("render_types")) {
-                var renderTypes = jsonObject.getAsJsonObject("render_types");
+            if (jsonObject.has(key)) {
+                var renderTypes = jsonObject.getAsJsonObject(key);
                 for (var entry : renderTypes.entrySet()) {
                     var renderType = ResourceLocation.parse(entry.getKey());
                     for (var layer : entry.getValue().getAsJsonArray())
                         if (renderTypeNames.put(layer.getAsInt(), renderType) != null)
-                            throw new JsonParseException("Registered duplicate render type for layer " + layer);
+                            throw new JsonParseException("Registered duplicate " + key + " for layer " + layer);
                 }
             }
 
-            return new ItemLayerModel(null, renderTypeNames);
+            return renderTypeNames;
         }
 
+        @Deprecated(forRemoval = true, since = "1.21.4")
         protected void readLayerData(JsonObject jsonObject, String name, Int2ObjectOpenHashMap<ResourceLocation> renderTypeNames, Int2ObjectMap<ForgeFaceData> layerData, boolean logWarning) {
             if (!jsonObject.has(name))
                 return;

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

@@ -250,6 +250,42 @@ public abstract class BlockStateProvider implements DataProvider {
             models().cubeColumnHorizontal(name(block) + "_horizontal", side, end).renderType(renderType));
     }
 
+    public void axisBlockWithRenderTypeAndFast(RotatedPillarBlock block, String renderType, String renderTypeFast) {
+        axisBlockWithRenderTypeAndFast(block, blockTexture(block), renderType, renderTypeFast);
+    }
+
+    public void logBlockWithRenderTypeAndFast(RotatedPillarBlock block, String renderType, String renderTypeFast) {
+        axisBlockWithRenderTypeAndFast(block, blockTexture(block), extend(blockTexture(block), "_top"), renderType, renderTypeFast);
+    }
+
+    public void axisBlockWithRenderTypeAndFast(RotatedPillarBlock block, ResourceLocation baseName, String renderType, String renderTypeFast) {
+        axisBlockWithRenderTypeAndFast(block, extend(baseName, "_side"), extend(baseName, "_end"), renderType, renderTypeFast);
+    }
+
+    public void axisBlockWithRenderTypeAndFast(RotatedPillarBlock block, ResourceLocation side, ResourceLocation end, String renderType, String renderTypeFast) {
+        axisBlock(block,
+            models().cubeColumn(name(block), side, end).renderType(renderType, renderTypeFast),
+            models().cubeColumnHorizontal(name(block) + "_horizontal", side, end).renderType(renderType, renderTypeFast));
+    }
+
+    public void axisBlockWithRenderTypeAndFast(RotatedPillarBlock block, ResourceLocation renderType, ResourceLocation renderTypeFast) {
+        axisBlockWithRenderTypeAndFast(block, blockTexture(block), renderType, renderTypeFast);
+    }
+
+    public void logBlockWithRenderType(RotatedPillarBlock block, ResourceLocation renderType, ResourceLocation renderTypeFast) {
+        axisBlockWithRenderTypeAndFast(block, blockTexture(block), extend(blockTexture(block), "_top"), renderType, renderTypeFast);
+    }
+
+    public void axisBlockWithRenderTypeAndFast(RotatedPillarBlock block, ResourceLocation baseName, ResourceLocation renderType, ResourceLocation renderTypeFast) {
+        axisBlockWithRenderTypeAndFast(block, extend(baseName, "_side"), extend(baseName, "_end"), renderType, renderTypeFast);
+    }
+
+    public void axisBlockWithRenderTypeAndFast(RotatedPillarBlock block, ResourceLocation side, ResourceLocation end, ResourceLocation renderType, ResourceLocation renderTypeFast) {
+        axisBlock(block,
+            models().cubeColumn(name(block), side, end).renderType(renderType, renderTypeFast),
+            models().cubeColumnHorizontal(name(block) + "_horizontal", side, end).renderType(renderType, renderTypeFast));
+    }
+
     public void axisBlock(RotatedPillarBlock block, ModelFile vertical, ModelFile horizontal) {
         getVariantBuilder(block)
             .partialState().with(RotatedPillarBlock.AXIS, Axis.Y)
@@ -381,6 +417,38 @@ public abstract class BlockStateProvider implements DataProvider {
         stairsBlockInternalWithRenderType(block, name + "_stairs", side, bottom, top, renderType);
     }
 
+    public void stairsBlockWithRenderTypeAndFast(StairBlock block, ResourceLocation texture, String renderType, String renderTypeFast) {
+        stairsBlockWithRenderTypeAndFast(block, texture, texture, texture, renderType, renderTypeFast);
+    }
+
+    public void stairsBlockWithRenderTypeAndFast(StairBlock block, String name, ResourceLocation texture, String renderType, String renderTypeFast) {
+        stairsBlockWithRenderTypeAndFast(block, name, texture, texture, texture, renderType, renderTypeFast);
+    }
+
+    public void stairsBlockWithRenderTypeAndFast(StairBlock block, ResourceLocation side, ResourceLocation bottom, ResourceLocation top, String renderType, String renderTypeFast) {
+        stairsBlockInternalWithRenderTypeAndFast(block, key(block).toString(), side, bottom, top, ResourceLocation.tryParse(renderType), ResourceLocation.tryParse(renderTypeFast));
+    }
+
+    public void stairsBlockWithRenderTypeAndFast(StairBlock block, String name, ResourceLocation side, ResourceLocation bottom, ResourceLocation top, String renderType, String renderTypeFast) {
+        stairsBlockInternalWithRenderTypeAndFast(block, name + "_stairs", side, bottom, top, ResourceLocation.tryParse(renderType), ResourceLocation.tryParse(renderTypeFast));
+    }
+
+    public void stairsBlockWithRenderTypeAndFast(StairBlock block, ResourceLocation texture, ResourceLocation renderType, ResourceLocation renderTypeFast) {
+        stairsBlockWithRenderTypeAndFast(block, texture, texture, texture, renderType, renderTypeFast);
+    }
+
+    public void stairsBlockWithRenderTypeAndFast(StairBlock block, String name, ResourceLocation texture, ResourceLocation renderType, ResourceLocation renderTypeFast) {
+        stairsBlockWithRenderTypeAndFast(block, name, texture, texture, texture, renderType, renderTypeFast);
+    }
+
+    public void stairsBlockWithRenderTypeAndFast(StairBlock block, ResourceLocation side, ResourceLocation bottom, ResourceLocation top, ResourceLocation renderType, ResourceLocation renderTypeFast) {
+        stairsBlockInternalWithRenderTypeAndFast(block, key(block).toString(), side, bottom, top, renderType, renderTypeFast);
+    }
+
+    public void stairsBlockWithRenderTypeAndFast(StairBlock block, String name, ResourceLocation side, ResourceLocation bottom, ResourceLocation top, ResourceLocation renderType, ResourceLocation renderTypeFast) {
+        stairsBlockInternalWithRenderTypeAndFast(block, name + "_stairs", side, bottom, top, renderType, renderTypeFast);
+    }
+
     private void stairsBlockInternal(StairBlock block, String baseName, ResourceLocation side, ResourceLocation bottom, ResourceLocation top) {
         ModelFile stairs = models().stairs(baseName, side, bottom, top);
         ModelFile stairsInner = models().stairsInner(baseName + "_inner", side, bottom, top);
@@ -395,6 +463,13 @@ public abstract class BlockStateProvider implements DataProvider {
         stairsBlock(block, stairs, stairsInner, stairsOuter);
     }
 
+    private void stairsBlockInternalWithRenderTypeAndFast(StairBlock block, String baseName, ResourceLocation side, ResourceLocation bottom, ResourceLocation top, ResourceLocation renderType, ResourceLocation renderTypeFast) {
+        ModelFile stairs = models().stairs(baseName, side, bottom, top).renderType(renderType, renderTypeFast);
+        ModelFile stairsInner = models().stairsInner(baseName + "_inner", side, bottom, top).renderType(renderType, renderTypeFast);
+        ModelFile stairsOuter = models().stairsOuter(baseName + "_outer", side, bottom, top).renderType(renderType, renderTypeFast);
+        stairsBlock(block, stairs, stairsInner, stairsOuter);
+    }
+
     public void stairsBlock(StairBlock block, ModelFile stairs, ModelFile stairsInner, ModelFile stairsOuter) {
         getVariantBuilder(block)
             .forAllStatesExcept(state -> {
@@ -532,6 +607,32 @@ public abstract class BlockStateProvider implements DataProvider {
             models().fenceSide(name + "_fence_side", texture).renderType(renderType));
     }
 
+    public void fenceBlockWithRenderTypeAndFast(FenceBlock block, ResourceLocation texture, String renderType, String renderTypeFast) {
+        String baseName = key(block).toString();
+        fourWayBlock(block,
+            models().fencePost(baseName + "_post", texture).renderType(renderType, renderTypeFast),
+            models().fenceSide(baseName + "_side", texture).renderType(renderType, renderTypeFast));
+    }
+
+    public void fenceBlockWithRenderTypeAndFast(FenceBlock block, String name, ResourceLocation texture, String renderType, String renderTypeFast) {
+        fourWayBlock(block,
+            models().fencePost(name + "_fence_post", texture).renderType(renderType, renderTypeFast),
+            models().fenceSide(name + "_fence_side", texture).renderType(renderType, renderTypeFast));
+    }
+
+    public void fenceBlockWithRenderTypeAndFast(FenceBlock block, ResourceLocation texture, ResourceLocation renderType, ResourceLocation renderTypeFast) {
+        String baseName = key(block).toString();
+        fourWayBlock(block,
+            models().fencePost(baseName + "_post", texture).renderType(renderType, renderTypeFast),
+            models().fenceSide(baseName + "_side", texture).renderType(renderType, renderTypeFast));
+    }
+
+    public void fenceBlockWithRenderTypeAndFast(FenceBlock block, String name, ResourceLocation texture, ResourceLocation renderType, ResourceLocation renderTypeFast) {
+        fourWayBlock(block,
+            models().fencePost(name + "_fence_post", texture).renderType(renderType, renderTypeFast),
+            models().fenceSide(name + "_fence_side", texture).renderType(renderType, renderTypeFast));
+    }
+
     public void fenceGateBlock(FenceGateBlock block, ResourceLocation texture) {
         fenceGateBlockInternal(block, key(block).toString(), texture);
     }
@@ -556,6 +657,22 @@ public abstract class BlockStateProvider implements DataProvider {
         fenceGateBlockInternalWithRenderType(block, name + "_fence_gate", texture, renderType);
     }
 
+    public void fenceGateBlockWithRenderTypeAndFast(FenceGateBlock block, ResourceLocation texture, String renderType, String renderTypeFast) {
+        fenceGateBlockInternalWithRenderTypeAndFast(block, key(block).toString(), texture, ResourceLocation.tryParse(renderType), ResourceLocation.tryParse(renderTypeFast));
+    }
+
+    public void fenceGateBlockWithRenderTypeAndFast(FenceGateBlock block, String name, ResourceLocation texture, String renderType, String renderTypeFast) {
+        fenceGateBlockInternalWithRenderTypeAndFast(block, name + "_fence_gate", texture, ResourceLocation.tryParse(renderType), ResourceLocation.tryParse(renderTypeFast));
+    }
+
+    public void fenceGateBlockWithRenderTypeAndFast(FenceGateBlock block, ResourceLocation texture, ResourceLocation renderType, ResourceLocation renderTypeFast) {
+        fenceGateBlockInternalWithRenderTypeAndFast(block, key(block).toString(), texture, renderType, renderTypeFast);
+    }
+
+    public void fenceGateBlockWithRenderTypeAndFast(FenceGateBlock block, String name, ResourceLocation texture, ResourceLocation renderType, ResourceLocation renderTypeFast) {
+        fenceGateBlockInternalWithRenderTypeAndFast(block, name + "_fence_gate", texture, renderType, renderTypeFast);
+    }
+
     private void fenceGateBlockInternal(FenceGateBlock block, String baseName, ResourceLocation texture) {
         ModelFile gate = models().fenceGate(baseName, texture);
         ModelFile gateOpen = models().fenceGateOpen(baseName + "_open", texture);
@@ -572,6 +689,14 @@ public abstract class BlockStateProvider implements DataProvider {
         fenceGateBlock(block, gate, gateOpen, gateWall, gateWallOpen);
     }
 
+    private void fenceGateBlockInternalWithRenderTypeAndFast(FenceGateBlock block, String baseName, ResourceLocation texture, ResourceLocation renderType, ResourceLocation renderTypeFast) {
+        ModelFile gate = models().fenceGate(baseName, texture).renderType(renderType, renderTypeFast);
+        ModelFile gateOpen = models().fenceGateOpen(baseName + "_open", texture).renderType(renderType, renderTypeFast);
+        ModelFile gateWall = models().fenceGateWall(baseName + "_wall", texture).renderType(renderType, renderTypeFast);
+        ModelFile gateWallOpen = models().fenceGateWallOpen(baseName + "_wall_open", texture).renderType(renderType, renderTypeFast);
+        fenceGateBlock(block, gate, gateOpen, gateWall, gateWallOpen);
+    }
+
     public void fenceGateBlock(FenceGateBlock block, ModelFile gate, ModelFile gateOpen, ModelFile gateWall, ModelFile gateWallOpen) {
         getVariantBuilder(block).forAllStatesExcept(state -> {
             ModelFile model = gate;
@@ -613,6 +738,22 @@ public abstract class BlockStateProvider implements DataProvider {
         wallBlockInternalWithRenderType(block, name + "_wall", texture, renderType);
     }
 
+    public void wallBlockWithRenderTypeAndFast(WallBlock block, ResourceLocation texture, String renderType, String renderTypeFast) {
+        wallBlockInternalWithRenderTypeAndFast(block, key(block).toString(), texture, ResourceLocation.tryParse(renderType), ResourceLocation.tryParse(renderTypeFast));
+    }
+
+    public void wallBlockWithRenderTypeAndFast(WallBlock block, String name, ResourceLocation texture, String renderType, String renderTypeFast) {
+        wallBlockInternalWithRenderTypeAndFast(block, name + "_wall", texture, ResourceLocation.tryParse(renderType), ResourceLocation.tryParse(renderTypeFast));
+    }
+
+    public void wallBlockWithRenderTypeAndFast(WallBlock block, ResourceLocation texture, ResourceLocation renderType, ResourceLocation renderTypeFast) {
+        wallBlockInternalWithRenderTypeAndFast(block, key(block).toString(), texture, renderType, renderTypeFast);
+    }
+
+    public void wallBlockWithRenderTypeAndFast(WallBlock block, String name, ResourceLocation texture, ResourceLocation renderType, ResourceLocation renderTypeFast) {
+        wallBlockInternalWithRenderTypeAndFast(block, name + "_wall", texture, renderType, renderTypeFast);
+    }
+
     private void wallBlockInternal(WallBlock block, String baseName, ResourceLocation texture) {
         wallBlock(block, models().wallPost(baseName + "_post", texture),
             models().wallSide(baseName + "_side", texture),
@@ -625,6 +766,12 @@ public abstract class BlockStateProvider implements DataProvider {
             models().wallSideTall(baseName + "_side_tall", texture).renderType(renderType));
     }
 
+    private void wallBlockInternalWithRenderTypeAndFast(WallBlock block, String baseName, ResourceLocation texture, ResourceLocation renderType, ResourceLocation renderTypeFast) {
+        wallBlock(block, models().wallPost(baseName + "_post", texture).renderType(renderType, renderTypeFast),
+            models().wallSide(baseName + "_side", texture).renderType(renderType, renderTypeFast),
+            models().wallSideTall(baseName + "_side_tall", texture).renderType(renderType, renderTypeFast));
+    }
+
     public static final ImmutableMap<Direction, Property<WallSide>> WALL_PROPS = ImmutableMap.<Direction, Property<WallSide>>builder()
             .put(Direction.EAST,  BlockStateProperties.EAST_WALL)
             .put(Direction.NORTH, BlockStateProperties.NORTH_WALL)
@@ -677,6 +824,22 @@ public abstract class BlockStateProvider implements DataProvider {
         paneBlockInternalWithRenderType(block, name + "_pane", pane, edge, renderType);
     }
 
+    public void paneBlockWithRenderTypeAndFast(IronBarsBlock block, ResourceLocation pane, ResourceLocation edge, String renderType, String renderTypeFast) {
+        paneBlockInternalWithRenderTypeAndFast(block, key(block).toString(), pane, edge, ResourceLocation.tryParse(renderType), ResourceLocation.tryParse(renderTypeFast));
+    }
+
+    public void paneBlockWithRenderTypeAndFast(IronBarsBlock block, String name, ResourceLocation pane, ResourceLocation edge, String renderType, String renderTypeFast) {
+        paneBlockInternalWithRenderTypeAndFast(block, name + "_pane", pane, edge, ResourceLocation.tryParse(renderType), ResourceLocation.tryParse(renderTypeFast));
+    }
+
+    public void paneBlockWithRenderTypeAndFast(IronBarsBlock block, ResourceLocation pane, ResourceLocation edge, ResourceLocation renderType, ResourceLocation renderTypeFast) {
+        paneBlockInternalWithRenderTypeAndFast(block, key(block).toString(), pane, edge, renderType, renderTypeFast);
+    }
+
+    public void paneBlockWithRenderTypeAndFast(IronBarsBlock block, String name, ResourceLocation pane, ResourceLocation edge, ResourceLocation renderType, ResourceLocation renderTypeFast) {
+        paneBlockInternalWithRenderTypeAndFast(block, name + "_pane", pane, edge, renderType, renderTypeFast);
+    }
+
     private void paneBlockInternal(IronBarsBlock block, String baseName, ResourceLocation pane, ResourceLocation edge) {
         ModelFile post = models().panePost(baseName + "_post", pane, edge);
         ModelFile side = models().paneSide(baseName + "_side", pane, edge);
@@ -695,6 +858,15 @@ public abstract class BlockStateProvider implements DataProvider {
         paneBlock(block, post, side, sideAlt, noSide, noSideAlt);
     }
 
+    private void paneBlockInternalWithRenderTypeAndFast(IronBarsBlock block, String baseName, ResourceLocation pane, ResourceLocation edge, ResourceLocation renderType, ResourceLocation renderTypeFast) {
+        ModelFile post = models().panePost(baseName + "_post", pane, edge).renderType(renderType, renderTypeFast);
+        ModelFile side = models().paneSide(baseName + "_side", pane, edge).renderType(renderType, renderTypeFast);
+        ModelFile sideAlt = models().paneSideAlt(baseName + "_side_alt", pane, edge).renderType(renderType, renderTypeFast);
+        ModelFile noSide = models().paneNoSide(baseName + "_noside", pane).renderType(renderType, renderTypeFast);
+        ModelFile noSideAlt = models().paneNoSideAlt(baseName + "_noside_alt", pane).renderType(renderType, renderTypeFast);
+        paneBlock(block, post, side, sideAlt, noSide, noSideAlt);
+    }
+
     public void paneBlock(IronBarsBlock block, ModelFile post, ModelFile side, ModelFile sideAlt, ModelFile noSide, ModelFile noSideAlt) {
         MultiPartBlockStateBuilder builder = getMultipartBuilder(block)
             .part().modelFile(post).addModel().end();
@@ -734,6 +906,22 @@ public abstract class BlockStateProvider implements DataProvider {
         doorBlockInternalWithRenderType(block, name + "_door", bottom, top, renderType);
     }
 
+    public void doorBlockWithRenderTypeAndFast(DoorBlock block, ResourceLocation bottom, ResourceLocation top, String renderType, String renderTypeFast) {
+        doorBlockInternalWithRenderTypeAndFast(block, key(block).toString(), bottom, top, ResourceLocation.tryParse(renderType), ResourceLocation.tryParse(renderTypeFast));
+    }
+
+    public void doorBlockWithRenderTypeAndFast(DoorBlock block, String name, ResourceLocation bottom, ResourceLocation top, String renderType, String renderTypeFast) {
+        doorBlockInternalWithRenderTypeAndFast(block, name + "_door", bottom, top, ResourceLocation.tryParse(renderType), ResourceLocation.tryParse(renderTypeFast));
+    }
+
+    public void doorBlockWithRenderTypeAndFast(DoorBlock block, ResourceLocation bottom, ResourceLocation top, ResourceLocation renderType, ResourceLocation renderTypeFast) {
+        doorBlockInternalWithRenderTypeAndFast(block, key(block).toString(), bottom, top, renderType, renderTypeFast);
+    }
+
+    public void doorBlockWithRenderTypeAndFast(DoorBlock block, String name, ResourceLocation bottom, ResourceLocation top, ResourceLocation renderType, ResourceLocation renderTypeFast) {
+        doorBlockInternalWithRenderTypeAndFast(block, name + "_door", bottom, top, renderType, renderTypeFast);
+    }
+
     private void doorBlockInternal(DoorBlock block, String baseName, ResourceLocation bottom, ResourceLocation top) {
         ModelFile bottomLeft = models().doorBottomLeft(baseName + "_bottom_left", bottom, top);
         ModelFile bottomLeftOpen = models().doorBottomLeftOpen(baseName + "_bottom_left_open", bottom, top);
@@ -758,6 +946,18 @@ public abstract class BlockStateProvider implements DataProvider {
         doorBlock(block, bottomLeft, bottomLeftOpen, bottomRight, bottomRightOpen, topLeft, topLeftOpen, topRight, topRightOpen);
     }
 
+    private void doorBlockInternalWithRenderTypeAndFast(DoorBlock block, String baseName, ResourceLocation bottom, ResourceLocation top, ResourceLocation renderType, ResourceLocation renderTypeFast) {
+        ModelFile bottomLeft = models().doorBottomLeft(baseName + "_bottom_left", bottom, top).renderType(renderType, renderTypeFast);
+        ModelFile bottomLeftOpen = models().doorBottomLeftOpen(baseName + "_bottom_left_open", bottom, top).renderType(renderType, renderTypeFast);
+        ModelFile bottomRight = models().doorBottomRight(baseName + "_bottom_right", bottom, top).renderType(renderType, renderTypeFast);
+        ModelFile bottomRightOpen = models().doorBottomRightOpen(baseName + "_bottom_right_open", bottom, top).renderType(renderType, renderTypeFast);
+        ModelFile topLeft = models().doorTopLeft(baseName + "_top_left", bottom, top).renderType(renderType, renderTypeFast);
+        ModelFile topLeftOpen = models().doorTopLeftOpen(baseName + "_top_left_open", bottom, top).renderType(renderType, renderTypeFast);
+        ModelFile topRight = models().doorTopRight(baseName + "_top_right", bottom, top).renderType(renderType, renderTypeFast);
+        ModelFile topRightOpen = models().doorTopRightOpen(baseName + "_top_right_open", bottom, top).renderType(renderType, renderTypeFast);
+        doorBlock(block, bottomLeft, bottomLeftOpen, bottomRight, bottomRightOpen, topLeft, topLeftOpen, topRight, topRightOpen);
+    }
+
     public void doorBlock(DoorBlock block, ModelFile bottomLeft, ModelFile bottomLeftOpen, ModelFile bottomRight, ModelFile bottomRightOpen, ModelFile topLeft, ModelFile topLeftOpen, ModelFile topRight, ModelFile topRightOpen) {
         getVariantBuilder(block).forAllStatesExcept(state -> {
             int yRot = ((int) state.getValue(DoorBlock.FACING).toYRot()) + 90;
@@ -824,6 +1024,22 @@ public abstract class BlockStateProvider implements DataProvider {
         trapdoorBlockInternalWithRenderType(block, name + "_trapdoor", texture, orientable, renderType);
     }
 
+    public void trapdoorBlockWithRenderTypeAndFast(TrapDoorBlock block, ResourceLocation texture, boolean orientable, String renderType, String renderTypeFast) {
+        trapdoorBlockInternalWithRenderTypeAndFast(block, key(block).toString(), texture, orientable, ResourceLocation.tryParse(renderType), ResourceLocation.tryParse(renderTypeFast));
+    }
+
+    public void trapdoorBlockWithRenderTypeAndFast(TrapDoorBlock block, String name, ResourceLocation texture, boolean orientable, String renderType, String renderTypeFast) {
+        trapdoorBlockInternalWithRenderTypeAndFast(block, name + "_trapdoor", texture, orientable, ResourceLocation.tryParse(renderType), ResourceLocation.tryParse(renderTypeFast));
+    }
+
+    public void trapdoorBlockWithRenderTypeAndFast(TrapDoorBlock block, ResourceLocation texture, boolean orientable, ResourceLocation renderType, ResourceLocation renderTypeFast) {
+        trapdoorBlockInternalWithRenderTypeAndFast(block, key(block).toString(), texture, orientable, renderType, renderTypeFast);
+    }
+
+    public void trapdoorBlockWithRenderTypeAndFast(TrapDoorBlock block, String name, ResourceLocation texture, boolean orientable, ResourceLocation renderType, ResourceLocation renderTypeFast) {
+        trapdoorBlockInternalWithRenderTypeAndFast(block, name + "_trapdoor", texture, orientable, renderType, renderTypeFast);
+    }
+
     private void trapdoorBlockInternal(TrapDoorBlock block, String baseName, ResourceLocation texture, boolean orientable) {
         ModelFile bottom = orientable ? models().trapdoorOrientableBottom(baseName + "_bottom", texture) : models().trapdoorBottom(baseName + "_bottom", texture);
         ModelFile top = orientable ? models().trapdoorOrientableTop(baseName + "_top", texture) : models().trapdoorTop(baseName + "_top", texture);
@@ -838,6 +1054,13 @@ public abstract class BlockStateProvider implements DataProvider {
         trapdoorBlock(block, bottom, top, open, orientable);
     }
 
+    private void trapdoorBlockInternalWithRenderTypeAndFast(TrapDoorBlock block, String baseName, ResourceLocation texture, boolean orientable, ResourceLocation renderType, ResourceLocation renderTypeFast) {
+        ModelFile bottom = orientable ? models().trapdoorOrientableBottom(baseName + "_bottom", texture).renderType(renderType, renderTypeFast) : models().trapdoorBottom(baseName + "_bottom", texture).renderType(renderType, renderTypeFast);
+        ModelFile top = orientable ? models().trapdoorOrientableTop(baseName + "_top", texture).renderType(renderType, renderTypeFast) : models().trapdoorTop(baseName + "_top", texture).renderType(renderType, renderTypeFast);
+        ModelFile open = orientable ? models().trapdoorOrientableOpen(baseName + "_open", texture).renderType(renderType, renderTypeFast) : models().trapdoorOpen(baseName + "_open", texture).renderType(renderType, renderTypeFast);
+        trapdoorBlock(block, bottom, top, open, orientable);
+    }
+
     public void trapdoorBlock(TrapDoorBlock block, ModelFile bottom, ModelFile top, ModelFile open, boolean orientable) {
         getVariantBuilder(block).forAllStatesExcept(state -> {
             int xRot = 0;

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

@@ -60,6 +60,7 @@ public class ModelBuilder<T extends ModelBuilder<T>> extends ModelFile {
     protected final ExistingFileHelper existingFileHelper;
 
     protected String renderType = null;
+    protected String renderTypeFast = null;
     protected boolean ambientOcclusion = true;
     protected GuiLight guiLight = null;
 
@@ -149,12 +150,17 @@ public class ModelBuilder<T extends ModelBuilder<T>> extends ModelFile {
     }
 
     /**
-     * Set the render type for this model.
+     * Set the render type for this model. Any render types to be used must be registered via
+     * {@link net.minecraftforge.client.event.RegisterNamedRenderTypesEvent RegisterNamedRenderTypesEvent}.
+     * <p>
+     * Consider using {@linkplain #renderType(String, String)} if you need to set a render type for
+     * {@linkplain net.minecraft.client.GraphicsStatus#FAST fast graphics}.
      *
-     * @param renderType the render type. Must be registered via
-     *                   {@link net.minecraftforge.client.event.RegisterNamedRenderTypesEvent}
+     * @param renderType the render type
      * @return this builder
-     * @throws NullPointerException  if {@code renderType} is {@code null}
+     *
+     * @throws NullPointerException if {@code renderType} is {@code null}
+     * @see #renderType(String, String)
      */
     public T renderType(String renderType) {
         Preconditions.checkNotNull(renderType, "Render type must not be null");
@@ -162,16 +168,55 @@ public class ModelBuilder<T extends ModelBuilder<T>> extends ModelFile {
     }
 
     /**
-     * Set the render type for this model.
+     * Set the render types for this model. Any render types to be used must be registered via
+     * {@link net.minecraftforge.client.event.RegisterNamedRenderTypesEvent RegisterNamedRenderTypesEvent}.
      *
-     * @param renderType the render type. Must be registered via
-     *                   {@link net.minecraftforge.client.event.RegisterNamedRenderTypesEvent}
+     * @param renderType     the render type for {@linkplain net.minecraft.client.GraphicsStatus#FANCY fancy graphics}
+     * @param renderTypeFast the render type for {@linkplain net.minecraft.client.GraphicsStatus#FAST fast graphics}
      * @return this builder
-     * @throws NullPointerException  if {@code renderType} is {@code null}
+     *
+     * @throws NullPointerException if {@code renderType} is {@code null}
+     */
+    public T renderType(String renderType, String renderTypeFast) {
+        Preconditions.checkNotNull(renderType, "Render type must not be null");
+        return renderType(ResourceLocation.parse(renderType), ResourceLocation.parse(renderTypeFast));
+    }
+
+    /**
+     * Set the render type for this model. Any render types to be used must be registered via
+     * {@link net.minecraftforge.client.event.RegisterNamedRenderTypesEvent RegisterNamedRenderTypesEvent}.
+     * <p>
+     * Consider using {@linkplain #renderType(ResourceLocation, ResourceLocation)} if you need to set a render type for
+     * {@linkplain net.minecraft.client.GraphicsStatus#FAST fast graphics}.
+     *
+     * @param renderType the render type
+     * @return this builder
+     *
+     * @throws NullPointerException if {@code renderType} is {@code null}
+     * @see #renderType(ResourceLocation, ResourceLocation)
      */
     public T renderType(ResourceLocation renderType) {
         Preconditions.checkNotNull(renderType, "Render type must not be null");
         this.renderType = renderType.toString();
+        this.renderTypeFast = null;
+        return self();
+    }
+
+    /**
+     * Set the render types for this model. Any render types to be used must be registered via
+     * {@link net.minecraftforge.client.event.RegisterNamedRenderTypesEvent RegisterNamedRenderTypesEvent}.
+     *
+     * @param renderType     the render type for {@linkplain net.minecraft.client.GraphicsStatus#FANCY fancy graphics}
+     * @param renderTypeFast the render type for {@linkplain net.minecraft.client.GraphicsStatus#FAST fast graphics}
+     * @return this builder
+     *
+     * @throws NullPointerException if {@code renderType} is {@code null}
+     */
+    public T renderType(ResourceLocation renderType, ResourceLocation renderTypeFast) {
+        Preconditions.checkNotNull(renderType, "Render type must not be null");
+        Preconditions.checkNotNull(renderTypeFast, "Fast graphics render type must not be null");
+        this.renderType = renderType.toString();
+        this.renderTypeFast = renderType.toString();
         return self();
     }
 

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

@@ -366,7 +366,8 @@ public abstract class ModelProvider<T extends ModelBuilder<T>> implements DataPr
     }
 
     public T leaves(String name, ResourceLocation texture) {
-        return singleTexture(name, BLOCK_FOLDER + "/leaves", "all", texture);
+        return singleTexture(name, BLOCK_FOLDER + "/leaves", "all", texture)
+            .renderType("cutout_mipped", "solid");
     }
 
     /**

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

@@ -34,6 +34,7 @@ public class ItemLayerModelBuilder<T extends ModelBuilder<T>> extends CustomLoad
 
     private final Int2ObjectMap<ForgeFaceData> faceData = new Int2ObjectOpenHashMap<>();
     private final Map<ResourceLocation, IntSet> renderTypes = new LinkedHashMap<>();
+    private final Map<ResourceLocation, IntSet> renderTypesFast = new LinkedHashMap<>();
     private final IntSet layersWithRenderTypes = new IntOpenHashSet();
 
     protected ItemLayerModelBuilder(T parent, ExistingFileHelper existingFileHelper)
@@ -116,6 +117,23 @@ public class ItemLayerModelBuilder<T extends ModelBuilder<T>> extends CustomLoad
         return renderType(asLoc, layers);
     }
 
+    public ItemLayerModelBuilder<T> renderType(String renderType, String renderTypeFast, int... layers)
+    {
+        Preconditions.checkNotNull(renderType, "Render type must not be null");
+        Preconditions.checkNotNull(renderTypeFast, "Fast graphics render type must not be null");
+        ResourceLocation asLoc;
+        if (renderType.contains(":"))
+            asLoc = ResourceLocation.parse(renderType);
+        else
+            asLoc = parent.getLocation().withPath(renderType);
+        ResourceLocation asLocFast;
+        if (renderTypeFast.contains(":"))
+            asLocFast = ResourceLocation.parse(renderTypeFast);
+        else
+            asLocFast = parent.getLocation().withPath(renderTypeFast);
+        return renderType(asLoc, asLocFast, layers);
+    }
+
     /**
      * Set the render type for a set of layers.
      *
@@ -145,6 +163,25 @@ public class ItemLayerModelBuilder<T extends ModelBuilder<T>> extends CustomLoad
         return this;
     }
 
+    public ItemLayerModelBuilder<T> renderType(ResourceLocation renderType, ResourceLocation renderTypeFast, int... layers)
+    {
+        Preconditions.checkNotNull(renderType, "Render type must not be null");
+        Preconditions.checkNotNull(renderTypeFast, "Fast graphics render type must not be null");
+        Preconditions.checkNotNull(layers, "Layers must not be null");
+        Preconditions.checkArgument(layers.length > 0, "At least one layer must be specified");
+        Preconditions.checkArgument(Arrays.stream(layers).allMatch(i -> i >= 0), "All layers must be >= 0");
+        var alreadyAssigned = Arrays.stream(layers).filter(layersWithRenderTypes::contains).toArray();
+        Preconditions.checkArgument(alreadyAssigned.length == 0, "Attempted to re-assign layer render types: " + Arrays.toString(alreadyAssigned));
+        var renderTypeLayers = renderTypes.computeIfAbsent(renderType, $ -> new IntOpenHashSet());
+        var renderTypeFastLayers = renderTypesFast.computeIfAbsent(renderType, $ -> new IntOpenHashSet());
+        Arrays.stream(layers).forEach(layer -> {
+            renderTypeLayers.add(layer);
+            renderTypeFastLayers.add(layer);
+            layersWithRenderTypes.add(layer);
+        });
+        return this;
+    }
+
     @Override
     public JsonObject toJson(JsonObject json)
     {
@@ -171,6 +208,14 @@ public class ItemLayerModelBuilder<T extends ModelBuilder<T>> extends CustomLoad
         });
         json.add("render_types", renderTypes);
 
+        JsonObject renderTypesFast = new JsonObject();
+        this.renderTypesFast.forEach((renderTypeFast, layers) -> {
+            JsonArray array = new JsonArray();
+            layers.intStream().sorted().forEach(array::add);
+            renderTypesFast.add(renderTypeFast.toString(), array);
+        });
+        json.add("render_types_fast", renderTypesFast);
+
         return json;
     }
 }

src/main/java/net/minecraftforge/client/model/geometry/BlockGeometryBakingContext.java

@@ -34,6 +34,8 @@ public class BlockGeometryBakingContext implements IGeometryBakingContext {
     private Transformation rootTransform;
     @Nullable
     private ResourceLocation renderTypeHint;
+    @Nullable
+    private ResourceLocation renderTypeFastHint;
     private boolean gui3d = true;
 
     @ApiStatus.Internal
@@ -115,10 +117,22 @@ public class BlockGeometryBakingContext implements IGeometryBakingContext {
         return owner.parent != null ? owner.parent.customData.getRenderTypeHint() : null;
     }
 
+    @Nullable
+    @Override
+    public ResourceLocation getRenderTypeFastHint() {
+        if (renderTypeFastHint != null)
+            return renderTypeFastHint;
+        return owner.parent != null ? owner.parent.customData.getRenderTypeFastHint() : null;
+    }
+
     public void setRenderTypeHint(ResourceLocation renderTypeHint) {
         this.renderTypeHint = renderTypeHint;
     }
 
+    public void setRenderTypeFastHint(ResourceLocation renderTypeFastHint) {
+        this.renderTypeFastHint = renderTypeFastHint;
+    }
+
     public void setGui3d(boolean gui3d) {
         this.gui3d = gui3d;
     }
@@ -128,6 +142,7 @@ public class BlockGeometryBakingContext implements IGeometryBakingContext {
         this.rootTransform = other.rootTransform;
         this.visibilityData.copyFrom(other.visibilityData);
         this.renderTypeHint = other.renderTypeHint;
+        this.renderTypeFastHint = other.renderTypeFastHint;
         this.gui3d = other.gui3d;
     }
 

src/main/java/net/minecraftforge/client/model/geometry/IGeometryBakingContext.java

@@ -74,6 +74,13 @@ public interface IGeometryBakingContext {
     @Nullable
     ResourceLocation getRenderTypeHint();
 
+    /**
+     * @return a hint of the {@linkplain net.minecraft.client.GraphicsStatus#FAST fast graphics} render type this model
+     * should use. Custom loaders may ignore this.
+     */
+    @Nullable
+    default ResourceLocation getRenderTypeFastHint() { return null; }
+
     /**
      * Queries the visibility of a component of this model.
      *
@@ -89,4 +96,20 @@ public interface IGeometryBakingContext {
     default RenderTypeGroup getRenderType(ResourceLocation name) {
         return NamedRenderTypeManager.get(name);
     }
+
+    /**
+     * {@return a {@link RenderTypeGroup} from the {@link #getRenderTypeHint()}, or the empty group if not found.}
+     */
+    default RenderTypeGroup getRenderType() {
+        var hint = getRenderTypeHint();
+        return hint == null ? RenderTypeGroup.EMPTY : getRenderType(hint);
+    }
+
+    /**
+     * {@return a {@link RenderTypeGroup} from the {@link #getRenderTypeHint()}, or the empty group if not found.}
+     */
+    default RenderTypeGroup getRenderTypeFast() {
+        var hint = getRenderTypeFastHint();
+        return hint == null ? RenderTypeGroup.EMPTY : getRenderType(hint);
+    }
 }

src/main/java/net/minecraftforge/client/model/geometry/SimpleUnbakedGeometry.java

@@ -25,10 +25,8 @@ public abstract class SimpleUnbakedGeometry<T extends SimpleUnbakedGeometry<T>>
     public BakedModel bake(IGeometryBakingContext context, ModelBaker baker, Function<Material, TextureAtlasSprite> spriteGetter, ModelState modelState) {
         TextureAtlasSprite particle = spriteGetter.apply(context.getMaterial("particle"));
 
-        var renderTypeHint = context.getRenderTypeHint();
-        var renderTypes = renderTypeHint != null ? context.getRenderType(renderTypeHint) : RenderTypeGroup.EMPTY;
         IModelBuilder<?> builder = IModelBuilder.of(context.useAmbientOcclusion(), context.useBlockLight(), context.isGui3d(),
-                context.getTransforms(), particle, renderTypes);
+                context.getTransforms(), particle, context.getRenderType(), context.getRenderTypeFast());
 
         addQuads(context, builder, baker, spriteGetter, modelState);
 

src/main/java/net/minecraftforge/client/model/geometry/StandaloneGeometryBakingContext.java

@@ -51,6 +51,8 @@ public class StandaloneGeometryBakingContext implements IGeometryBakingContext {
     private final Transformation rootTransform;
     @Nullable
     private final ResourceLocation renderTypeHint;
+    @Nullable
+    private final ResourceLocation renderTypeFastHint;
     private final BiPredicate<String, Boolean> visibilityTest;
 
     private StandaloneGeometryBakingContext(
@@ -60,6 +62,18 @@ public class StandaloneGeometryBakingContext implements IGeometryBakingContext {
         ItemTransforms transforms, Transformation rootTransform,
         @Nullable ResourceLocation renderTypeHint,
         BiPredicate<String, Boolean> visibilityTest
+    ) {
+        this(modelName, materialCheck, materialLookup, isGui3d, useBlockLight, useAmbientOcclusion, transforms, rootTransform, renderTypeHint, null, visibilityTest);
+    }
+
+    private StandaloneGeometryBakingContext(
+        ResourceLocation modelName, Predicate<String> materialCheck,
+        Function<String, Material> materialLookup, boolean isGui3d,
+        boolean useBlockLight, boolean useAmbientOcclusion,
+        ItemTransforms transforms, Transformation rootTransform,
+        @Nullable ResourceLocation renderTypeHint,
+        @Nullable ResourceLocation renderTypeFastHint,
+        BiPredicate<String, Boolean> visibilityTest
     ) {
         this.modelName = modelName;
         this.materialCheck = materialCheck;
@@ -70,6 +84,7 @@ public class StandaloneGeometryBakingContext implements IGeometryBakingContext {
         this.transforms = transforms;
         this.rootTransform = rootTransform;
         this.renderTypeHint = renderTypeHint;
+        this.renderTypeFastHint = renderTypeFastHint;
         this.visibilityTest = visibilityTest;
     }
 
@@ -119,6 +134,12 @@ public class StandaloneGeometryBakingContext implements IGeometryBakingContext {
         return renderTypeHint;
     }
 
+    @Nullable
+    @Override
+    public ResourceLocation getRenderTypeFastHint() {
+        return renderTypeFastHint;
+    }
+
     @Override
     public boolean isComponentVisible(String component, boolean fallback) {
         return visibilityTest.test(component, fallback);
@@ -143,6 +164,8 @@ public class StandaloneGeometryBakingContext implements IGeometryBakingContext {
         private Transformation rootTransform = Transformation.identity();
         @Nullable
         private ResourceLocation renderTypeHint;
+        @Nullable
+        private ResourceLocation renderTypeFastHint;
         private BiPredicate<String, Boolean> visibilityTest = (c, def) -> def;
 
         private Builder() { }
@@ -156,6 +179,7 @@ public class StandaloneGeometryBakingContext implements IGeometryBakingContext {
             this.transforms = parent.getTransforms();
             this.rootTransform = parent.getRootTransform();
             this.renderTypeHint = parent.getRenderTypeHint();
+            this.renderTypeFastHint = parent.getRenderTypeFastHint();
             this.visibilityTest = parent::isComponentVisible;
         }
 
@@ -205,6 +229,12 @@ public class StandaloneGeometryBakingContext implements IGeometryBakingContext {
             return this;
         }
 
+        public Builder withRenderTypeHint(ResourceLocation renderTypeHint, ResourceLocation renderTypeFastHint) {
+            this.renderTypeHint = renderTypeHint;
+            this.renderTypeFastHint = renderTypeFastHint;
+            return this;
+        }
+
         @SuppressWarnings("deprecation")
         public Builder withVisibleComponents(Object2BooleanMap<String> parts) {
             this.visibilityTest = parts::getOrDefault;
@@ -212,7 +242,7 @@ public class StandaloneGeometryBakingContext implements IGeometryBakingContext {
         }
 
         public StandaloneGeometryBakingContext build(ResourceLocation modelName) {
-            return new StandaloneGeometryBakingContext(modelName, materialCheck, materialLookup, isGui3d, useBlockLight, useAmbientOcclusion, transforms, rootTransform, renderTypeHint, visibilityTest);
+            return new StandaloneGeometryBakingContext(modelName, materialCheck, materialLookup, isGui3d, useBlockLight, useAmbientOcclusion, transforms, rootTransform, renderTypeHint, renderTypeFastHint, visibilityTest);
         }
     }
 }