Add back Forge item model shaper mixin

neoforge/src/main/java/org/embeddedt/modernfix/neoforge/mixin/perf/dynamic_resources/ItemModelMesherForgeMixin.java

@@ -0,0 +1,83 @@
+package org.embeddedt.modernfix.neoforge.mixin.perf.dynamic_resources;
+
+import net.minecraft.client.renderer.ItemModelShaper;
+import net.minecraft.client.resources.model.BakedModel;
+import net.minecraft.client.resources.model.ModelManager;
+import net.minecraft.client.resources.model.ModelResourceLocation;
+import net.minecraft.core.Holder;
+import net.minecraft.resources.ResourceLocation;
+import net.minecraft.world.item.Item;
+import net.neoforged.neoforge.client.model.RegistryAwareItemModelShaper;
+import org.embeddedt.modernfix.annotation.ClientOnlyMixin;
+import org.embeddedt.modernfix.dynamicresources.ModelLocationCache;
+import org.embeddedt.modernfix.util.ItemMesherMap;
+import org.spongepowered.asm.mixin.*;
+import org.spongepowered.asm.mixin.injection.At;
+import org.spongepowered.asm.mixin.injection.Inject;
+import org.spongepowered.asm.mixin.injection.callback.CallbackInfo;
+
+import java.util.HashMap;
+import java.util.Map;
+
+@Mixin(RegistryAwareItemModelShaper.class)
+@ClientOnlyMixin
+public abstract class ItemModelMesherForgeMixin extends ItemModelShaper {
+    @Shadow(remap = false) @Final @Mutable private Map<Holder.Reference<Item>, ModelResourceLocation> locations;
+
+    private Map<Holder.Reference<Item>, ModelResourceLocation> overrideLocations;
+
+    public ItemModelMesherForgeMixin(ModelManager arg) {
+        super(arg);
+    }
+
+    private static final ModelResourceLocation SENTINEL = new ModelResourceLocation(new ResourceLocation("modernfix", "sentinel"), "sentinel");
+
+    @Inject(method = "<init>", at = @At("RETURN"))
+    private void replaceLocationMap(CallbackInfo ci) {
+        overrideLocations = new HashMap<>();
+        // need to replace this map because mods query locations through it
+        locations = new ItemMesherMap<>(this::mfix$getLocationForge);
+    }
+
+    @Unique
+    private ModelResourceLocation mfix$getLocationForge(Holder.Reference<Item> item) {
+        ModelResourceLocation map = overrideLocations.getOrDefault(item, SENTINEL);
+        if(map == SENTINEL) {
+            /* generate the appropriate location from our cache */
+            map = ModelLocationCache.get(item.value());
+        }
+        return map;
+    }
+
+    /**
+     * @author embeddedt
+     * @reason Get the stored location for that item and meta, and get the model
+     * from that location from the model manager.
+     **/
+    @Overwrite
+    @Override
+    public BakedModel getItemModel(Item item) {
+        ModelResourceLocation map = mfix$getLocationForge(item.builtInRegistryHolder());
+        return map == null ? null : getModelManager().getModel(map);
+    }
+
+    /**
+     * @author embeddedt
+     * @reason Don't get all models during init (with dynamic loading, that would
+     * generate them all). Just store location instead.
+     **/
+    @Overwrite
+    @Override
+    public void register(Item item, ModelResourceLocation location) {
+        overrideLocations.put(item.builtInRegistryHolder(), location);
+    }
+
+    /**
+     * @author embeddedt
+     * @reason Disable cache rebuilding (with dynamic loading, that would generate
+     * all models).
+     **/
+    @Overwrite
+    @Override
+    public void rebuildCache() {}
+}