[glTF] Patch uv2 naming for shaders.

examples/js/loaders/GLTF2Loader.js

@@ -735,6 +735,11 @@ THREE.GLTF2Loader = ( function () {
 					shaderText = shaderText.replace( regEx, 'uv' );
 					break;
 
+				case 'TEXCOORD_1':
+
+					shaderText = shaderText.replace( regEx, 'uv2' );
+					break;
+
 				case 'COLOR_0':
 				case 'COLOR0':
 				case 'COLOR':

examples/js/loaders/GLTFLoader.js

@@ -745,6 +745,11 @@ THREE.GLTFLoader = ( function () {
 					shaderText = shaderText.replace( regEx, 'uv' );
 					break;
 
+				case 'TEXCOORD_1':
+
+					shaderText = shaderText.replace( regEx, 'uv2' );
+					break;
+
 				case 'COLOR_0':
 				case 'COLOR0':
 				case 'COLOR':