function preventDefault (context, path, commands, iterator) {
    if (context._webGLRenderer) context._webGLRenderer.getOrSetCutout(path);
    context._domRenderer.preventDefault(commands[++iterator]);
    return iterator;
}
Getter method used for retrieving the used WebGLRenderer (if any).

@method

@return {WebGLRenderer|null}    The WebGLRenderer being used by the Context.