Merge pull request #2086 from codex128/issue2083

Fixes Issue #2083 (enable vertex colors in glTF loader)

jme3-examples/src/main/java/jme3test/model/TestGltfVertexColor.java

@@ -0,0 +1,73 @@
+/*
+ * Copyright (c) 2009-2023 jMonkeyEngine
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ * * Redistributions of source code must retain the above copyright
+ *   notice, this list of conditions and the following disclaimer.
+ *
+ * * Redistributions in binary form must reproduce the above copyright
+ *   notice, this list of conditions and the following disclaimer in the
+ *   documentation and/or other materials provided with the distribution.
+ *
+ * * Neither the name of 'jMonkeyEngine' nor the names of its contributors
+ *   may be used to endorse or promote products derived from this software
+ *   without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
+ * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+package jme3test.model;
+
+import com.jme3.app.*;
+import com.jme3.math.*;
+import com.jme3.renderer.Limits;
+import com.jme3.renderer.queue.RenderQueue;
+import com.jme3.scene.*;
+import com.jme3.scene.plugins.gltf.GltfModelKey;
+
+public class TestGltfVertexColor extends SimpleApplication {
+    Node probeNode;
+
+    public static void main(String[] args) {
+        TestGltfVertexColor app = new TestGltfVertexColor();
+        app.start();
+    }
+
+    @Override
+    public void simpleInitApp() {
+        rootNode.setShadowMode(RenderQueue.ShadowMode.CastAndReceive);
+        probeNode = (Node) assetManager.loadModel("Scenes/defaultProbe.j3o");
+        rootNode.attachChild(probeNode);
+
+        cam.setFrustumPerspective(45f, (float) cam.getWidth() / cam.getHeight(), 0.1f, 100f);
+        renderer.setDefaultAnisotropicFilter(Math.min(renderer.getLimits().get(Limits.TextureAnisotropy), 8));
+        setPauseOnLostFocus(false);
+
+        flyCam.setEnabled(false);
+        viewPort.setBackgroundColor(new ColorRGBA().setAsSrgb(0.2f, 0.2f, 0.2f, 1.0f));
+
+        loadModel("jme3test/gltfvertexcolor/VertexColorTest.glb", new Vector3f(0, -1, 0), 1);
+    }
+
+    private void loadModel(String path, Vector3f offset, float scale) {
+        GltfModelKey k = new GltfModelKey(path);
+        Spatial s = assetManager.loadModel(k);
+        s.scale(scale);
+        s.move(offset);
+        probeNode.attachChild(s);
+    }
+
+}

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

@@ -385,6 +385,8 @@ public class GltfLoader implements AssetLoader {
                 JsonObject attributes = meshObject.getAsJsonObject("attributes");
                 assertNotNull(attributes, "No attributes defined for mesh " + mesh);
 
+                boolean useVertexColors = false;
+
                 skinBuffers.clear();
 
                 for (Map.Entry<String, JsonElement> entry : attributes.entrySet()) {
@@ -408,6 +410,10 @@ public class GltfLoader implements AssetLoader {
                             mesh.setBuffer(vb);
                         }
                     }
+                    // if the color buffer is used, we will need to enable vertex colors on the material
+                    if (bufferType.startsWith("COLOR")) {
+                        useVertexColors = true;
+                    }
                 }
                 handleSkinningBuffers(mesh, skinBuffers);
 
@@ -476,6 +482,10 @@ public class GltfLoader implements AssetLoader {
                     }
                 }
 
+                if (useVertexColors) {
+                    geom.getMaterial().setBoolean("UseVertexColor", useVertexColors);
+                }
+
                 geom.setName(name + "_" + index);
                 
                 geom.updateModelBound();