Use morphTargetsRelative in GLTF loader

This uses the newly added functionality for loading morph target data in
GLTF loader; there's no need to clone attribute data anymore.

examples/js/loaders/GLTFLoader.js

@@ -1309,95 +1309,9 @@ THREE.GLTFLoader = ( function () {
 			var morphPositions = accessors[ 0 ];
 			var morphNormals = accessors[ 1 ];
 
-			// Clone morph target accessors before modifying them.
-
-			for ( var i = 0, il = morphPositions.length; i < il; i ++ ) {
-
-				if ( geometry.attributes.position === morphPositions[ i ] ) continue;
-
-				morphPositions[ i ] = cloneBufferAttribute( morphPositions[ i ] );
-
-			}
-
-			for ( var i = 0, il = morphNormals.length; i < il; i ++ ) {
-
-				if ( geometry.attributes.normal === morphNormals[ i ] ) continue;
-
-				morphNormals[ i ] = cloneBufferAttribute( morphNormals[ i ] );
-
-			}
-
-			for ( var i = 0, il = targets.length; i < il; i ++ ) {
-
-				var target = targets[ i ];
-				var attributeName = 'morphTarget' + i;
-
-				if ( hasMorphPosition ) {
-
-					// Three.js morph position is absolute value. The formula is
-					//   basePosition
-					//     + weight0 * ( morphPosition0 - basePosition )
-					//     + weight1 * ( morphPosition1 - basePosition )
-					//     ...
-					// while the glTF one is relative
-					//   basePosition
-					//     + weight0 * glTFmorphPosition0
-					//     + weight1 * glTFmorphPosition1
-					//     ...
-					// then we need to convert from relative to absolute here.
-
-					if ( target.POSITION !== undefined ) {
-
-						var positionAttribute = morphPositions[ i ];
-						positionAttribute.name = attributeName;
-
-						var position = geometry.attributes.position;
-
-						for ( var j = 0, jl = positionAttribute.count; j < jl; j ++ ) {
-
-							positionAttribute.setXYZ(
-								j,
-								positionAttribute.getX( j ) + position.getX( j ),
-								positionAttribute.getY( j ) + position.getY( j ),
-								positionAttribute.getZ( j ) + position.getZ( j )
-							);
-
-						}
-
-					}
-
-				}
-
-				if ( hasMorphNormal ) {
-
-					// see target.POSITION's comment
-
-					if ( target.NORMAL !== undefined ) {
-
-						var normalAttribute = morphNormals[ i ];
-						normalAttribute.name = attributeName;
-
-						var normal = geometry.attributes.normal;
-
-						for ( var j = 0, jl = normalAttribute.count; j < jl; j ++ ) {
-
-							normalAttribute.setXYZ(
-								j,
-								normalAttribute.getX( j ) + normal.getX( j ),
-								normalAttribute.getY( j ) + normal.getY( j ),
-								normalAttribute.getZ( j ) + normal.getZ( j )
-							);
-
-						}
-
-					}
-
-				}
-
-			}
-
 			if ( hasMorphPosition ) geometry.morphAttributes.position = morphPositions;
 			if ( hasMorphNormal ) geometry.morphAttributes.normal = morphNormals;
+			geometry.morphTargetsRelative = true;
 
 			return geometry;
 
@@ -1485,31 +1399,6 @@ THREE.GLTFLoader = ( function () {
 
 	}
 
-	function cloneBufferAttribute( attribute ) {
-
-		if ( attribute.isInterleavedBufferAttribute ) {
-
-			var count = attribute.count;
-			var itemSize = attribute.itemSize;
-			var array = attribute.array.slice( 0, count * itemSize );
-
-			for ( var i = 0, j = 0; i < count; ++ 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 );
-
-			}
-
-			return new THREE.BufferAttribute( array, itemSize, attribute.normalized );
-
-		}
-
-		return attribute.clone();
-
-	}
-
 	/* GLTF PARSER */
 
 	function GLTFParser( json, extensions, options ) {

examples/jsm/loaders/GLTFLoader.js

@@ -1373,95 +1373,9 @@ var GLTFLoader = ( function () {
 			var morphPositions = accessors[ 0 ];
 			var morphNormals = accessors[ 1 ];
 
-			// Clone morph target accessors before modifying them.
-
-			for ( var i = 0, il = morphPositions.length; i < il; i ++ ) {
-
-				if ( geometry.attributes.position === morphPositions[ i ] ) continue;
-
-				morphPositions[ i ] = cloneBufferAttribute( morphPositions[ i ] );
-
-			}
-
-			for ( var i = 0, il = morphNormals.length; i < il; i ++ ) {
-
-				if ( geometry.attributes.normal === morphNormals[ i ] ) continue;
-
-				morphNormals[ i ] = cloneBufferAttribute( morphNormals[ i ] );
-
-			}
-
-			for ( var i = 0, il = targets.length; i < il; i ++ ) {
-
-				var target = targets[ i ];
-				var attributeName = 'morphTarget' + i;
-
-				if ( hasMorphPosition ) {
-
-					// Three.js morph position is absolute value. The formula is
-					//   basePosition
-					//     + weight0 * ( morphPosition0 - basePosition )
-					//     + weight1 * ( morphPosition1 - basePosition )
-					//     ...
-					// while the glTF one is relative
-					//   basePosition
-					//     + weight0 * glTFmorphPosition0
-					//     + weight1 * glTFmorphPosition1
-					//     ...
-					// then we need to convert from relative to absolute here.
-
-					if ( target.POSITION !== undefined ) {
-
-						var positionAttribute = morphPositions[ i ];
-						positionAttribute.name = attributeName;
-
-						var position = geometry.attributes.position;
-
-						for ( var j = 0, jl = positionAttribute.count; j < jl; j ++ ) {
-
-							positionAttribute.setXYZ(
-								j,
-								positionAttribute.getX( j ) + position.getX( j ),
-								positionAttribute.getY( j ) + position.getY( j ),
-								positionAttribute.getZ( j ) + position.getZ( j )
-							);
-
-						}
-
-					}
-
-				}
-
-				if ( hasMorphNormal ) {
-
-					// see target.POSITION's comment
-
-					if ( target.NORMAL !== undefined ) {
-
-						var normalAttribute = morphNormals[ i ];
-						normalAttribute.name = attributeName;
-
-						var normal = geometry.attributes.normal;
-
-						for ( var j = 0, jl = normalAttribute.count; j < jl; j ++ ) {
-
-							normalAttribute.setXYZ(
-								j,
-								normalAttribute.getX( j ) + normal.getX( j ),
-								normalAttribute.getY( j ) + normal.getY( j ),
-								normalAttribute.getZ( j ) + normal.getZ( j )
-							);
-
-						}
-
-					}
-
-				}
-
-			}
-
 			if ( hasMorphPosition ) geometry.morphAttributes.position = morphPositions;
 			if ( hasMorphNormal ) geometry.morphAttributes.normal = morphNormals;
+			geometry.morphTargetsRelative = true;
 
 			return geometry;
 
@@ -1549,31 +1463,6 @@ var GLTFLoader = ( function () {
 
 	}
 
-	function cloneBufferAttribute( attribute ) {
-
-		if ( attribute.isInterleavedBufferAttribute ) {
-
-			var count = attribute.count;
-			var itemSize = attribute.itemSize;
-			var array = attribute.array.slice( 0, count * itemSize );
-
-			for ( var i = 0, j = 0; i < count; ++ 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 );
-
-			}
-
-			return new BufferAttribute( array, itemSize, attribute.normalized );
-
-		}
-
-		return attribute.clone();
-
-	}
-
 	/* GLTF PARSER */
 
 	function GLTFParser( json, extensions, options ) {