Adding full support for custom materials to GltfLoader

jme3-plugins/src/gltf/java/com/jme3/scene/plugins/gltf/CustomContentManager.java

@@ -214,7 +214,7 @@ private <T> T readExtension(String name, JsonElement el, T input) throws AssetLo
                 continue;
             }
             try {
-                return (T) loader.handleExtension(gltfLoader, name, el, ext.getValue(), input);
+                input = (T) loader.handleExtension(gltfLoader, name, el, ext.getValue(), input);
             } catch (ClassCastException e) {
                 throw new AssetLoadException("Extension loader " + loader.getClass().getName() + " for extension " + ext.getKey() + " is incompatible with type " + input.getClass(), e);
             }

jme3-plugins/src/gltf/java/com/jme3/scene/plugins/gltf/GltfLoader.java

@@ -31,6 +31,7 @@
  */
 package com.jme3.scene.plugins.gltf;
 
+import static com.jme3.scene.plugins.gltf.GltfMaterialData.*;
 import static com.jme3.scene.plugins.gltf.GltfUtils.assertNotNull;
 import static com.jme3.scene.plugins.gltf.GltfUtils.findCommonAncestor;
 import static com.jme3.scene.plugins.gltf.GltfUtils.getAdapterForMaterial;
@@ -82,7 +83,7 @@
 import com.jme3.asset.AssetLoader;
 import com.jme3.asset.TextureKey;
 import com.jme3.material.Material;
-import com.jme3.material.RenderState;
+import com.jme3.material.RenderState.BlendMode;
 import com.jme3.math.ColorRGBA;
 import com.jme3.math.FastMath;
 import com.jme3.math.Matrix4f;
@@ -109,6 +110,7 @@
 import com.jme3.util.BufferInputStream;
 import com.jme3.util.BufferUtils;
 import com.jme3.util.IntMap;
+import com.jme3.util.SafeArrayList;
 import com.jme3.util.mikktspace.MikktspaceTangentGenerator;
 
 /**
@@ -143,13 +145,20 @@ public class GltfLoader implements AssetLoader {
     private final Vector3fArrayPopulator vector3fArrayPopulator = new Vector3fArrayPopulator();
     private final QuaternionArrayPopulator quaternionArrayPopulator = new QuaternionArrayPopulator();
     private final Matrix4fArrayPopulator matrix4fArrayPopulator = new Matrix4fArrayPopulator();
-    private final Map<String, MaterialAdapter> defaultMaterialAdapters = new HashMap<>();
+    @Deprecated private final Map<String, MaterialAdapter> defaultMaterialAdapters = new HashMap<>();
     private final CustomContentManager customContentManager = new CustomContentManager();
     private boolean useNormalsFlag = false;
 
     Map<SkinData, List<Spatial>> skinnedSpatials = new HashMap<>();
     private final IntMap<SkinBuffers> skinBuffers = new IntMap<>();
 
+    private static SafeArrayList<GltfMaterialFactory> materialFactoryList = new SafeArrayList<>(GltfMaterialFactory.class);
+
+    static {
+        materialFactoryList.add(new UnshadedMaterialFactory());
+        materialFactoryList.add(new PBRLightingMaterialFactory());
+    }
+
     public GltfLoader() {
         defaultMaterialAdapters.put("pbrMetallicRoughness", new PBRMetalRoughMaterialAdapter());
     }
@@ -526,9 +535,10 @@ public Geometry[] readMeshPrimitives(int meshIndex) throws IOException {
                     geom.setMaterial(defaultMat);
                 } else {
                     useNormalsFlag = false;
-                    geom.setMaterial(readMaterial(materialIndex));
-                    if (geom.getMaterial().getAdditionalRenderState()
-                            .getBlendMode() == RenderState.BlendMode.Alpha) {
+                    Material material = readMaterial(materialIndex, useVertexColors);
+                    geom.setMaterial(material);
+                    BlendMode blendMode = material.getAdditionalRenderState().getBlendMode();
+                    if (blendMode == BlendMode.Alpha || blendMode == BlendMode.AlphaAdditive) {
                         // Alpha blending is enabled for this material. Let's place the geom in the
                         // transparent bucket.
                         geom.setQueueBucket(RenderQueue.Bucket.Transparent);
@@ -540,10 +550,6 @@ public Geometry[] readMeshPrimitives(int meshIndex) throws IOException {
                     }
                 }
 
-                if (useVertexColors) {
-                    geom.getMaterial().setBoolean("UseVertexColor", useVertexColors);
-                }
-
                 geom.setName(name + "_" + index);
 
                 geom.updateModelBound();
@@ -802,7 +808,75 @@ protected ByteBuffer getBytes(int bufferIndex, String uri, Integer bufferLength)
         return data;
     }
 
-    public Material readMaterial(int materialIndex) throws IOException {
+    public Material readMaterial(int materialIndex, boolean usesVertexColors) throws IOException {
+        // Fallback to the old material adapter system, if the legacy flag is set.
+        if (GltfUtils.isMaterialAdaptersEnabled(info)) {
+            return readMaterialUsingMaterialAdapters(materialIndex);
+        }
+
+        assertNotNull(materials, "There is no material defined yet a mesh references one");
+        JsonObject materialJson = materials.get(materialIndex).getAsJsonObject();
+
+        GltfMaterialData gltfMaterialData = readStandardMaterialParameters(materialJson);
+        gltfMaterialData.setHasVertexColors(usesVertexColors);
+        gltfMaterialData = customContentManager.readExtensionAndExtras("material", materialJson, gltfMaterialData);
+        return createMaterial(gltfMaterialData, materialIndex);
+    }
+
+    protected GltfMaterialData readStandardMaterialParameters(JsonObject materialJson) throws IOException {
+        GltfMaterialData gltfMaterialData = new GltfMaterialData();
+        gltfMaterialData.setGltfParam(MATERIAL_NAME_PARAM, getAsString(materialJson, "name"));
+
+        JsonObject pbrMetallicRoughnessJson = materialJson.getAsJsonObject("pbrMetallicRoughness");
+        if (pbrMetallicRoughnessJson != null) {
+            gltfMaterialData.setGltfParam(BASE_COLOR_PARAM, getAsColor(pbrMetallicRoughnessJson, "baseColorFactor"));
+            gltfMaterialData.setGltfParam(BASE_COLOR_TEXTURE_PARAM, getAsTexture2D(pbrMetallicRoughnessJson, "baseColorTexture"));
+            gltfMaterialData.setGltfParam(METALLIC_FACTOR_PARAM, getAsFloat(pbrMetallicRoughnessJson, "metallicFactor"));
+            gltfMaterialData.setGltfParam(ROUGHNESS_FACTOR_PARAM, getAsFloat(pbrMetallicRoughnessJson, "roughnessFactor"));
+            gltfMaterialData.setGltfParam(METALLIC_ROUGHNESS_TEXTURE_PARAM, getAsTexture2D(pbrMetallicRoughnessJson, "metallicRoughnessTexture"));
+        }
+
+        JsonObject normalTextureJson = materialJson.getAsJsonObject("normalTexture");
+        if (normalTextureJson != null) {
+            gltfMaterialData.setGltfParam(NORMAL_TEXTURE_PARAM, readTexture(normalTextureJson));
+            gltfMaterialData.setGltfParam(NORMAL_SCALE_PARAM, getAsFloat(normalTextureJson, "scale"));
+            useNormalsFlag = true;
+        }
+
+        JsonObject occlusionTextureJson = materialJson.getAsJsonObject("occlusionTexture");
+        if (occlusionTextureJson != null) {
+            gltfMaterialData.setGltfParam(OCCLUSION_TEXTURE_PARAM, readTexture(occlusionTextureJson));
+            gltfMaterialData.setGltfParam(OCCLUSION_TEXTURE_STRENGTH_PARAM, getAsFloat(occlusionTextureJson, "strength"));
+        }
+
+        gltfMaterialData.setGltfParam(EMISSIVE_TEXTURE_PARAM, getAsTexture2D(materialJson, "emissiveTexture"));
+        gltfMaterialData.setGltfParam(EMISSIVE_COLOR_PARAM, getAsColor(materialJson, "emissiveFactor"));
+
+        String alphaMode = getAsString(materialJson, "alphaMode");
+        gltfMaterialData.setGltfParam(ALPHA_MODE_PARAM, alphaMode);
+        if ("MASK".equals(alphaMode)) {
+            gltfMaterialData.setGltfParam(ALPHA_CUTOFF_PARAM, getAsFloat(materialJson, "alphaCutoff"));
+        }
+
+        gltfMaterialData.setGltfParam(DOUBLE_SIDED_PARAM, getAsBoolean(materialJson, "doubleSided"));
+
+        return gltfMaterialData;
+    }
+
+    protected Material createMaterial(GltfMaterialData gltfMaterialData, int materialIndex) {
+        for (GltfMaterialFactory gltfMaterialFactory : materialFactoryList) {
+            if (gltfMaterialFactory.accepts(info.getKey(), gltfMaterialData)) {
+                return gltfMaterialFactory.createMaterial(info.getManager(), info.getKey(), gltfMaterialData);
+            }
+        }
+
+        logger.log(Level.WARNING, "Couldn't find any matching GltfMaterialFactory for material " + materialIndex);
+        useNormalsFlag = false;
+        return defaultMat;
+    }
+
+    @Deprecated
+    protected Material readMaterialUsingMaterialAdapters(int materialIndex) throws IOException {
         assertNotNull(materials, "There is no material defined yet a mesh references one");
 
         JsonObject matData = materials.get(materialIndex).getAsJsonObject();
@@ -922,6 +996,10 @@ public void readCameras() throws IOException {
         }
     }
 
+    protected Texture2D getAsTexture2D(JsonObject jsonObject, String textureName) throws IOException {
+        return readTexture(jsonObject.getAsJsonObject(textureName));
+    }
+
     public Texture2D readTexture(JsonObject texture) throws IOException {
         return readTexture(texture, false);
     }
@@ -1715,4 +1793,44 @@ public static void registerDefaultExtrasLoader(Class<? extends ExtrasLoader> loa
     public static void unregisterDefaultExtrasLoader() {
         CustomContentManager.defaultExtraLoaderClass = UserDataLoader.class;
     }
+
+    /**
+     * Registers a new material factory and places it before all existing factories.<br/>
+     * The ordering of these factories defines their priority. When a new material needs to be created,
+     * the loader searches for the first material factory that accepts the given material data.
+     *
+     * @param materialFactory The {@link GltfMaterialFactory} to register.
+     */
+    public static void registerMaterialFactoryFirst(GltfMaterialFactory materialFactory) {
+            unregisterMaterialFactory(materialFactory.getClass());
+            materialFactoryList.add(0, materialFactory);
+    }
+
+    /**
+     * Registers a new material factory and places it behind all existing factories.<br/>
+     * The ordering of these factories defines their priority. When a new material needs to be created,
+     * the loader searches for the first material factory that accepts the given material data.
+     *
+     * @param materialFactory The {@link GltfMaterialFactory} to register.
+     */
+    public static void registerMaterialFactoryLast(GltfMaterialFactory materialFactory) {
+        unregisterMaterialFactory(materialFactory.getClass());
+        materialFactoryList.add(materialFactory);
+    }
+
+    /**
+     * Unregisters a material factory by its class.
+     *
+     * @param materialFactoryClass The class of the {@link GltfMaterialFactory} to unregister.
+     */
+    public static void unregisterMaterialFactory(Class<? extends GltfMaterialFactory> materialFactoryClass) {
+        materialFactoryList.removeIf(materialFactoryClass::isInstance);
+    }
+
+    /**
+     * Unregisters all material factories.
+     */
+    public static void unregisterAllMaterialFactories() {
+        materialFactoryList.clear();
+    }
 }