void checkObjectDragged(int prevX, int prevY, int deltaX, int deltaY, int modifiers) {
		for (int i = 0; i < JmolConstants.SHAPE_MAX; ++i) {
			Shape shape = frame.shapes[i];
			if (shape != null) {
				shape.checkObjectDragged(prevX, prevY, deltaX, deltaY, modifiers);
			}
		}
	}