Merge pull request #15438 from donmccurdy/bug-gltfloader-clone-interleaved

GLTFLoader: Fix bug with certain interleaved attributes.

examples/js/loaders/GLTFLoader.js

@@ -1611,12 +1611,12 @@ THREE.GLTFLoader = ( function () {
 			var itemSize = attribute.itemSize;
 			var array = attribute.array.slice( 0, count * itemSize );
 
-			for ( var i = 0; i < count; ++ i ) {
+			for ( var i = 0, j = 0; i < count; ++ i ) {
 
-				array[ i ] = attribute.getX( i );
-				if ( itemSize >= 2 ) array[ i + 1 ] = attribute.getY( i );
-				if ( itemSize >= 3 ) array[ i + 2 ] = attribute.getZ( i );
-				if ( itemSize >= 4 ) array[ i + 3 ] = attribute.getW( i );
+				array[ j ++ ] = attribute.getX( i );
+				if ( itemSize >= 2 ) array[ j ++ ] = attribute.getY( i );
+				if ( itemSize >= 3 ) array[ j ++ ] = attribute.getZ( i );
+				if ( itemSize >= 4 ) array[ j ++ ] = attribute.getW( i );
 
 			}