code: private boolean checkPoint(int mx, int my, ControlPoint pt) {
  		int dx = (int) Math.abs((10+(width * pt.pos)) - mx);
  		int dy = Math.abs((y+barHeight+7)-my);
  		
  		if ((dx < 5) && (dy < 7)) {
  			return true;
  		}
  		
  		return false;
  	}
docs: Check if there is a control point at the specified mouse location
  
  @param mx The mouse x coordinate
  @param my The mouse y coordinate
  @param pt The point to check agianst
  @return True if the mouse point conincides with the control point