void frameControl(Token token, boolean isSubCmd) throws ScriptException {
		switch (token.tok) {
		case Token.playrev:
			viewer.reverseAnimation();
		case Token.play:
		case Token.resume:
			viewer.resumeAnimation();
			return;
		case Token.pause:
			viewer.pauseAnimation();
			return;
		case Token.next:
			viewer.setAnimationNext();
			return;
		case Token.prev:
			viewer.setAnimationPrevious();
			return;
		case Token.rewind:
			viewer.rewindAnimation();
			return;
		default:
			evalError(GT._("invalid {0} control keyword", "frame") + ": " + token.toString());
		}
	}