c++ - Qt - 需要递归重绘，怎么样？

Question

我有以下代码:

paintGL()
{

    if(mouse_was_clicked)
    {
       ... do the color picking with openGL to identify a clicked element

       ... !!! now I need to call again paintGL() to switch the selected element from the 
              old one to the new one but I can't create a recursive cycle!
    }
    else
    {
       ... normal code to draw the scene and the selected element in red ...
    }
}

如行所示，我需要一种方法来再次调用绘制事件。有没有什么方法可以在不创建潜在活锁的情况下完成此操作？比如推迟新的油漆事件？

Answer 1

如果您的 paintGL() 中的控制流如此简单，只需确保当前在 else block 中的内容在每种情况下都被执行:

void MyWidget::paintGL()
{
    if(mouse_was_clicked)
    {
        ... do the color picking with openGL to identify a clicked element
    }

    ... normal code to draw the scene and the selected element in red ...
}