谷歌开发的draco格式文件将obj文件压缩成drc文件后将大大减小文件大小（threejs加载有mtl文件的drc文件）

问题描述：当前threejs是92版本 但是当前版本还没有能够直接加载带贴图文件的drc格式的loader；

解决办法：先加载mtl文件将obj文件分解（按照mtl文件内材质贴图信息进行分解）再将分解的obj文件转成drc全部加载一遍就能解决贴图的办法 ；

代码：

 THREE.Loader.Handlers.add( /.dds$/i, new THREE.DDSLoader() );
        var modelObject = new THREE.Object3D();
        var loadNum = 0;
        var mtlLoader = new THREE.MTLLoader();
//        new THREE.MTLLoader()
        mtlLoader.setPath( '__PUBLIC__/wap/dracoModel/0518xialian/' );
        mtlLoader.load( 'cs.mtl', function ( materials ) {
                materials.preload();
                new THREE.OBJLoader()
                    .setMaterials( materials )
                    .setPath( '__PUBLIC__/wap/dracoModel/0518xialian/' )
                    .load( 'cs.obj', function ( object ) {

//                        object.position.x = -0.55;
//                        object.position.y = -0;
//                        object.position.z = 1.1;
                        object.scale.x = 0.0005;
                        object.scale.y = 0.0005;
                        object.scale.z = 0.0005;
                        scene.add( object );

                    }, onProgress, onError );

//        dracoLoader.load( '__PUBLIC__/wap/images/bunny.drc', function ( geometry ) {

//                    dracoLoader.load( '__PUBLIC__/wap/dracoModel/9015/1.drc', function ( geometry ) {
//                        geometry.computeVertexNormals();
//                        var material = new THREE.MeshStandardMaterial( { vertexColors: THREE.VertexColors } );
//                        var mesh = new THREE.Mesh( geometry, material );
//                        mesh.castShadow = true;
//                        mesh.receiveShadow = true;
////            mesh.position.x = -10;
////            mesh.position.y = -5;
////            mesh.position.z = -10;
//                        mesh.scale.x = 0.005;
//                        mesh.scale.y = 0.005;
//                        mesh.scale.z = 0.005;
//                        scene.add( mesh );
//
//                        // Release decoder resources.
//                        THREE.DRACOLoader.releaseDecoderModule();
//
//                    } );


            //将素材加载到场景中回掉函数
            var loaderCallback = function(geometry) {

                var material = null;
//                console.log(loadNum);
                if(loadNum === drcNameArray.length-1){
                    scene.add(modelObject);
                }else{
                    geometry.computeVertexNormals();
                    var midName = drcNameArray[loadNum].split('.')[1];
//                    midName = midName.slice(0,2);
                     material = materials.materials[midName];
                     console.log(midName);
//                     console.log(drcNameArray[loadNum].split('.')[1]);
//                     console.log(materials.materials);
                    var mesh = new THREE.Mesh( geometry, material );
                    mesh.castShadow = true;
                    mesh.receiveShadow = true;
                    mesh.scale.x = 0.0003;
                    mesh.scale.y = 0.0003;
                    mesh.scale.z = 0.0003;
//                        // Release decoder resources.
//                        THREE.DRACOLoader.releaseDecoderModule();
                    modelObject.add(mesh);
                    loadNum++;
//                    console.log(loadNum)
                    dracoLoader.load("__PUBLIC__/wap/dracoModel/hongpei01/drc/" + [drcNameArray[loadNum]],loaderCallback,function(){});
                }
                // item.halfSize = getObjectHalfSize(modelObject);

            };
//            dracoLoader.load("__PUBLIC__/wap/dracoModel/hongpei01/drc/" + drcNameArray[0],loaderCallback,function(){});
            //将素材加载到场景中回掉函数end
            } );

描述：目前我们是这么解决的；