setImageSmoothingEnabled(enabled){
            if( this._imageSmoothingEnabled !== enabled ){
                this._imageSmoothingEnabled = enabled;
                this.setInternalCacheNeedsRefresh();
                this.viewer.forceRedraw();
            }
        }
Sets whether image smoothing is enabled or disabled
@param {Boolean} enabled If true, uses gl.LINEAR as the TEXTURE_MIN_FILTER and TEXTURE_MAX_FILTER, otherwise gl.NEAREST.