QGLWidget中的渲染和颜色选择:如何应对这两者

时间:2012-07-21 12:25:51

标签: c++ qt opengl qglwidget double-buffering

我想知道是否有比这更好的解决方案:我有渲染代码和颜色选择代码,我已经分享了可以在这两个代码(VBO等等)之间共享的所有东西,我的代码看起来像:

void paintGL()
{

label1:

  if(picking_running)
  {
     ... code to draw the colors for the picking
  }
  else
  {
     ... normal code to draw the scene the user should see
  }


  if(picking_running)
  {
      ... do the colorpick and identify the clicked element...

     picking_running = FALSE;

     goto label1; // this prevent the paintGL function to end and get swapBuffers called, I don't want the "flickering" to be visible to the user between the color picking mode and the normal mode

  }

} // end of the paintGL, here swapBuffers is called automatically

代码有效,并且用户看不到任何闪烁,但坦率地说,在我的代码中转到goto的想法似乎是一个糟糕的解决方案。

你还有其他更好的主意吗?

2 个答案:

答案 0 :(得分:1)

使用setAutoBufferSwap(false)并自己调用QGLWidget :: swapBuffers。您还可以将采样渲染为未渲染的缓冲区/纹理。

答案 1 :(得分:1)

因为无论如何都要执行可见渲染,为什么不这样实现它:

void paintGL()
{
  if(picking_running)
  {
     /* ... code to draw the colors for the picking */

     /* ... do the colorpick and identify the clicked element... */
  }

  /* ... normal code to draw the scene the user should see */
}