Add EntityRenderState to IClientItemExtensions#get*ArmorModel

patches/net/minecraft/client/renderer/entity/EntityRenderDispatcher.java.patch

@@ -1,5 +1,13 @@
 --- a/net/minecraft/client/renderer/entity/EntityRenderDispatcher.java
 +++ b/net/minecraft/client/renderer/entity/EntityRenderDispatcher.java
+@@ -203,6 +_,7 @@
+             }
+
+             p_363537_.popPose();
++            net.neoforged.neoforge.client.renderstate.RenderStateExtensions.unsetEntityRenderState();
+         } catch (Throwable throwable) {
+             CrashReport crashreport = CrashReport.forThrowable(throwable, "Rendering entity in world");
+             CrashReportCategory crashreportcategory = crashreport.addCategory("Entity being rendered");
 @@ -246,12 +_,12 @@
      ) {
          AABB aabb = p_114444_.getBoundingBox().move(-p_114444_.getX(), -p_114444_.getY(), -p_114444_.getZ());

patches/net/minecraft/client/renderer/entity/layers/EquipmentLayerRenderer.java.patch

@@ -5,7 +5,7 @@
          @Nullable ResourceLocation p_371639_
      ) {
 +        net.neoforged.neoforge.client.extensions.common.IClientItemExtensions extensions = net.neoforged.neoforge.client.extensions.common.IClientItemExtensions.of(p_371670_);
-+        p_371731_ = extensions.getGenericArmorModel(p_371670_, p_387484_, p_371731_);
++        p_371731_ = net.neoforged.neoforge.client.ClientHooks.getGenericArmorModel(extensions, p_371670_, p_387484_, p_371731_);
          List<EquipmentClientInfo.Layer> list = this.equipmentAssets.get(p_387603_).getLayers(p_387484_);
          if (!list.isEmpty()) {
 -            int i = p_371670_.is(ItemTags.DYEABLE) ? DyedItemColor.getOrDefault(p_371670_, 0) : 0;

src/main/java/net/neoforged/neoforge/client/ClientHooks.java

@@ -51,6 +51,7 @@
 import net.minecraft.client.gui.screens.inventory.tooltip.ClientTooltipComponent;
 import net.minecraft.client.gui.screens.inventory.tooltip.ClientTooltipPositioner;
 import net.minecraft.client.model.HumanoidModel;
+import net.minecraft.client.model.Model;
 import net.minecraft.client.model.geom.ModelLayerLocation;
 import net.minecraft.client.model.geom.builders.LayerDefinition;
 import net.minecraft.client.multiplayer.ClientLevel;
@@ -181,6 +182,7 @@
 import net.neoforged.neoforge.client.gui.map.MapDecorationRendererManager;
 import net.neoforged.neoforge.client.model.data.ModelData;
 import net.neoforged.neoforge.client.renderstate.RegisterRenderStateModifiersEvent;
+import net.neoforged.neoforge.client.renderstate.RenderStateExtensions;
 import net.neoforged.neoforge.common.NeoForge;
 import net.neoforged.neoforge.common.NeoForgeMod;
 import net.neoforged.neoforge.forge.snapshots.ForgeSnapshotsModClient;
@@ -255,6 +257,10 @@ public static float getGuiFarPlane() {
         return 11_000F + depth;
     }
 
+    public static Model getGenericArmorModel(IClientItemExtensions extensions, ItemStack itemStack, EquipmentClientInfo.LayerType layerType, Model original) {
+        return extensions.getGenericArmorModel(itemStack, RenderStateExtensions.getCurrentRenderState(), layerType, original);
+    }
+
     public static ResourceLocation getArmorTexture(ItemStack armor, EquipmentClientInfo.LayerType type, EquipmentClientInfo.Layer layer, ResourceLocation _default) {
         ResourceLocation result = IClientItemExtensions.of(armor).getArmorTexture(armor, type, layer, _default);
         return result != null ? result : _default;

src/main/java/net/neoforged/neoforge/client/extensions/common/IClientItemExtensions.java

@@ -13,6 +13,7 @@
 import net.minecraft.client.model.Model;
 import net.minecraft.client.player.LocalPlayer;
 import net.minecraft.client.renderer.entity.layers.EquipmentLayerRenderer;
+import net.minecraft.client.renderer.entity.state.EntityRenderState;
 import net.minecraft.client.resources.model.EquipmentClientInfo;
 import net.minecraft.core.component.DataComponents;
 import net.minecraft.resources.ResourceLocation;
@@ -93,31 +94,33 @@ default boolean applyForgeHandTransform(PoseStack poseStack, LocalPlayer player,
     /**
      * Queries the humanoid armor model for this item when it's equipped.
      *
-     * @param itemStack The item stack
-     * @param layerType The slot the item is in
-     * @param original  The original armor model. Will have attributes set.
+     * @param itemStack   The item stack
+     * @param renderState The state of the entity being rendered
+     * @param layerType   The slot the item is in
+     * @param original    The original armor model. Will have attributes set.
      * @return A HumanoidModel to be rendered. Relevant properties are to be copied over by the caller.
-     * @see #getGenericArmorModel(ItemStack, EquipmentClientInfo.LayerType, Model)
+     * @see #getGenericArmorModel(ItemStack, EntityRenderState, EquipmentClientInfo.LayerType, Model)
      */
-    default Model getHumanoidArmorModel(ItemStack itemStack, EquipmentClientInfo.LayerType layerType, Model original) {
+    default Model getHumanoidArmorModel(ItemStack itemStack, EntityRenderState renderState, EquipmentClientInfo.LayerType layerType, Model original) {
         return original;
     }
 
     /**
      * Queries the armor model for this item when it's equipped. Useful in place of
-     * {@link #getHumanoidArmorModel(ItemStack, EquipmentClientInfo.LayerType, Model)} for wrapping the original
+     * {@link #getHumanoidArmorModel(ItemStack, EntityRenderState, EquipmentClientInfo.LayerType, Model)} for wrapping the original
      * model or returning anything non-standard.
      * <p>
      * If you override this method you are responsible for copying any properties you care about from the original model.
      *
-     * @param itemStack The item stack
-     * @param layerType The slot the item is in
-     * @param original  The original armor model. Will have attributes set.
+     * @param itemStack   The item stack
+     * @param renderState The state of the entity being rendered
+     * @param layerType   The slot the item is in
+     * @param original    The original armor model. Will have attributes set.
      * @return A Model to be rendered. Relevant properties must be copied over manually.
-     * @see #getHumanoidArmorModel(ItemStack, EquipmentClientInfo.LayerType, Model)
+     * @see #getHumanoidArmorModel(ItemStack, EntityRenderState, EquipmentClientInfo.LayerType, Model)
      */
-    default Model getGenericArmorModel(ItemStack itemStack, EquipmentClientInfo.LayerType layerType, Model original) {
-        Model replacement = getHumanoidArmorModel(itemStack, layerType, original);
+    default Model getGenericArmorModel(ItemStack itemStack, EntityRenderState renderState, EquipmentClientInfo.LayerType layerType, Model original) {
+        Model replacement = getHumanoidArmorModel(itemStack, renderState, layerType, original);
         if (replacement != original) {
             if (original instanceof HumanoidModel<?> originalHumanoid && replacement instanceof HumanoidModel<?> replacementHumanoid) {
                 ClientHooks.copyModelProperties(originalHumanoid, replacementHumanoid);
@@ -127,23 +130,6 @@ default Model getGenericArmorModel(ItemStack itemStack, EquipmentClientInfo.Laye
         return original;
     }
 
-    /**
-     * Called when an armor piece is about to be rendered, allowing parts of the model to be animated or changed.
-     *
-     * @param itemStack       The item stack being worn
-     * @param livingEntity    The entity wearing the armor
-     * @param equipmentSlot   The slot the armor stack is being worn in
-     * @param model           The armor model being rendered
-     * @param limbSwing       The swing position of the entity's walk animation
-     * @param limbSwingAmount The swing speed of the entity's walk animation
-     * @param partialTick     The partial tick time
-     * @param ageInTicks      The total age of the entity, with partialTick already applied
-     * @param netHeadYaw      The yaw (Y rotation) of the entity's head
-     * @param headPitch       The pitch (X rotation) of the entity's head
-     */
-    // TODO 1.21.2: add back patch that calls this method from HumanoidArmorLayer
-    default void setupModelAnimations(LivingEntity livingEntity, ItemStack itemStack, EquipmentSlot equipmentSlot, Model model, float limbSwing, float limbSwingAmount, float partialTick, float ageInTicks, float netHeadYaw, float headPitch) {}
-
     /**
      * Called to render an overlay on the first-person camera.
      * <p>

src/main/java/net/neoforged/neoforge/client/renderstate/RenderStateExtensions.java

@@ -33,6 +33,8 @@ private RenderStateExtensions() {}
 
     private static final Map<ResourceKey<MapDecorationType>, Collection<MapDecorationRenderStateModifier>> MAP_DECORATION = new Reference2ObjectArrayMap<>();
 
+    private static final ThreadLocal<EntityRenderState> RENDERING_STATE = ThreadLocal.withInitial(() -> null);
+
     @SuppressWarnings("unchecked")
     @ApiStatus.Internal
     public static <E extends Entity, S extends EntityRenderState> void onUpdateEntityRenderState(EntityRenderer<E, S> renderer, E entity, S renderState) {
@@ -49,6 +51,16 @@ public static <E extends Entity, S extends EntityRenderState> void onUpdateEntit
         for (BiConsumer<E, S> modifier : modifiers) {
             modifier.accept(entity, renderState);
         }
+
+        RENDERING_STATE.set(renderState);
+    }
+
+    public static EntityRenderState getCurrentRenderState() {
+        return RENDERING_STATE.get();
+    }
+
+    public static void unsetEntityRenderState() {
+        RENDERING_STATE.remove();
     }
 
     @ApiStatus.Internal

tests/src/main/java/net/neoforged/neoforge/debug/client/ClientTests.java

@@ -13,9 +13,12 @@
 import net.minecraft.client.KeyMapping;
 import net.minecraft.client.Minecraft;
 import net.minecraft.client.gui.GuiGraphics;
+import net.minecraft.client.model.Model;
 import net.minecraft.client.renderer.RenderType;
+import net.minecraft.client.renderer.entity.state.EntityRenderState;
 import net.minecraft.client.renderer.texture.MissingTextureAtlasSprite;
 import net.minecraft.client.renderer.texture.TextureAtlas;
+import net.minecraft.client.resources.model.EquipmentClientInfo;
 import net.minecraft.client.resources.sounds.AbstractSoundInstance;
 import net.minecraft.client.resources.sounds.Sound;
 import net.minecraft.client.resources.sounds.SoundInstance;
@@ -24,11 +27,14 @@
 import net.minecraft.network.chat.Component;
 import net.minecraft.resources.ResourceLocation;
 import net.minecraft.sounds.SoundSource;
+import net.minecraft.util.Mth;
 import net.minecraft.world.entity.EquipmentSlot;
 import net.minecraft.world.entity.player.Player;
 import net.minecraft.world.item.Item;
 import net.minecraft.world.item.ItemStack;
 import net.minecraft.world.item.Items;
+import net.minecraft.world.item.equipment.ArmorMaterials;
+import net.minecraft.world.item.equipment.ArmorType;
 import net.minecraft.world.phys.Vec3;
 import net.neoforged.api.distmarker.Dist;
 import net.neoforged.neoforge.client.event.ClientChatEvent;
@@ -143,6 +149,26 @@ public void renderFirstPersonOverlay(ItemStack stack, EquipmentSlot equipmentSlo
         });
     }
 
+    @TestHolder(description = "Tests that the render state can be properly accessed when choosing an armor model for an item.", enabledByDefault = true)
+    static void renderStateOnEquipment(final DynamicTest test) {
+        var item = test.registrationHelper().items().registerItem("wiggling_chestplate", properties -> new Item(ArmorMaterials.IRON.humanoidProperties(properties, ArmorType.CHESTPLATE)));
+        test.framework().modEventBus().addListener((final RegisterClientExtensionsEvent event) -> event.registerItem(new IClientItemExtensions() {
+            @Override
+            public Model getGenericArmorModel(ItemStack itemStack, EntityRenderState renderState, EquipmentClientInfo.LayerType layerType, Model original) {
+                var result = IClientItemExtensions.super.getGenericArmorModel(itemStack, renderState, layerType, original);
+                result.root().yRot = 0.35F * Mth.sin(0.6F * renderState.ageInTicks);
+                return result;
+            }
+        }, item));
+        test.eventListeners().forge().addListener((final PlayerEvent.PlayerLoggedInEvent event) -> {
+            // Give item to player for testing
+            event.getEntity().addItem(item.toStack());
+
+            // Request confirmation from the player
+            test.requestConfirmation(event.getEntity(), Component.literal("Does the 'wiggling_chestplate' wiggle while being worn?"));
+        });
+    }
+
     private static final class SineSound extends AbstractSoundInstance {
         SineSound(Vec3 position) {
             super(ResourceLocation.fromNamespaceAndPath("neotests_audio_stream_test", "sine_wave"), SoundSource.BLOCKS, SoundInstance.createUnseededRandom());

tests/src/main/java/net/neoforged/neoforge/oldtest/client/CustomArmorModelTest.java

@@ -9,6 +9,7 @@
 import net.minecraft.client.model.HumanoidModel;
 import net.minecraft.client.model.Model;
 import net.minecraft.client.model.geom.ModelLayers;
+import net.minecraft.client.renderer.entity.state.EntityRenderState;
 import net.minecraft.client.renderer.entity.state.HumanoidRenderState;
 import net.minecraft.client.resources.model.EquipmentClientInfo;
 import net.minecraft.core.component.DataComponents;
@@ -70,7 +71,7 @@ private static final class ClientEvents {
         private static void onRegisterClientExtensions(RegisterClientExtensionsEvent event) {
             event.registerItem(new IClientItemExtensions() {
                 @Override
-                public HumanoidModel<?> getHumanoidArmorModel(ItemStack itemStack, EquipmentClientInfo.LayerType armorSlot, Model _default) {
+                public HumanoidModel<?> getHumanoidArmorModel(ItemStack itemStack, EntityRenderState renderState, EquipmentClientInfo.LayerType armorSlot, Model _default) {
                     return ENDERMAN.get();
                 }