For a simple OpenGL code:
Qt Code: 
  1. void display(void)
  2. {
  3.    glClear(GL_COLOR_BUFFER_BIT);
  4.  
  5.    glColor3f (0.0, 1.0, 0.0);
  6.    glPushMatrix();
  7.    glRotatef(-rotAngle, 0.0, 0.0, 0.1);
  8.    glBegin (GL_LINES);
  9.       glVertex2f (-0.5, 0.5);
  10.       glVertex2f (0.5, -0.5);
  11.    glEnd ();
  12.    glPopMatrix();
  13.  
  14.    glColor3f (0.0, 0.0, 1.0);
  15.    glPushMatrix();
  16.    glRotatef(rotAngle, 0.0, 0.0, 0.1);
  17.    glBegin (GL_LINES);
  18.       glVertex2f (0.5, 0.5);
  19.       glVertex2f (-0.5, -0.5);
  20.    glEnd ();
  21.    glPopMatrix();
  22.  
  23.    glFlush();
  24. }
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I mean, whether I could add the lines drawn by OpenGL as a path defined by QPainterPath ?

Then I could operate using the "path" more easily.

Thanks a lot