//override
    _resetAssembler () {
        this.setVertsDirty(true);
        this._assembler = new CustomAssembler();
        this._assembler.init(this);
    }

    //override
    _activateMaterial () {
        let material = this.sharedMaterials[0];
        if (!material) {
            this.disableRender();
            return;
        }
        
        material = cc.Material.getInstantiatedMaterial(material, this);
        this.setMaterial(0, material);
        this.markForRender(true);
    }

   init (comp) {
        super.init(comp);
        this._renderData = new cc.RenderData();
        this._renderData.init(this);

        this.initLocal();
        this.initData();
    }

    //override
    updateRenderData (comp) {
        if (comp._vertsDirty) {
            this.updateUVs(comp);
            this.updateVerts(comp);
            comp._vertsDirty = false;
        }
    }