GLTFLoader: Explicitly clone ShaderMaterial properties.

examples/js/loaders/GLTFLoader.js

@@ -451,6 +451,32 @@ THREE.GLTFLoader = ( function () {
 
 			name: EXTENSIONS.KHR_MATERIALS_PBR_SPECULAR_GLOSSINESS,
 
+			specularGlossinessParams: [
+				'color',
+				'map',
+				'lightMap',
+				'lightMapIntensity',
+				'aoMap',
+				'aoMapIntensity',
+				'emissive',
+				'emissiveIntensity',
+				'emissiveMap',
+				'bumpMap',
+				'bumpScale',
+				'normalMap',
+				'displacementMap',
+				'displacementScale',
+				'displacementBias',
+				'specularMap',
+				'specular',
+				'glossinessMap',
+				'glossiness',
+				'alphaMap',
+				'envMap',
+				'envMapIntensity',
+				'refractionRatio',
+			],
+
 			getMaterialType: function () {
 
 				return THREE.ShaderMaterial;
@@ -629,6 +655,24 @@ THREE.GLTFLoader = ( function () {
 
 			},
 
+			cloneMaterial: function ( source ) {
+
+				var target = source.clone();
+
+				target.isGLTFSpecularGlossinessMaterial = true;
+
+				var params = this.specularGlossinessParams;
+
+				for ( var i = 0; i < params.length; i ++ ) {
+
+					target[ params[ i ] ] = source[ params[ i ] ];
+
+				}
+
+				return target;
+
+			},
+
 			// Here's based on refreshUniformsCommon() and refreshUniformsStandard() in WebGLRenderer.
 			refreshUniforms: function ( renderer, scene, camera, geometry, material, group ) {
 
@@ -1799,6 +1843,7 @@ THREE.GLTFLoader = ( function () {
 
 		var scope = this;
 		var json = this.json;
+		var extensions = this.extensions;
 
 		return this._withDependencies( [
 
@@ -1838,7 +1883,16 @@ THREE.GLTFLoader = ( function () {
 
 						if ( useVertexColors || useFlatShading ) {
 
-							material = material.clone();
+							if ( material.isGLTFSpecularGlossinessMaterial ) {
+
+								var specGlossExtension = extensions[ EXTENSIONS.KHR_MATERIALS_PBR_SPECULAR_GLOSSINESS ];
+								material = specGlossExtension.cloneMaterial( material );
+
+							} else {
+
+								material = material.clone();
+
+							}
 
 						}