opengl: glFlush() vs. glFinish()

Question

I\'m having trouble distinguishing the practical difference between calling glFlush() and glFinish().

The docs say that glFlush()

Answer 1

Have a look here. In short, it says:

glFinish() has the same effect as glFlush(), with the addition that glFinish() will block until all commands submitted have been executed.

Another article describes other differences:

• Swap functions (used in double-buffered applications) automatically flush the commands, so no need to call glFlush
• glFinish forces OpenGL to perform outstanding commands, which is a bad idea (e.g. with VSync)

To sum up, this means that you don't even need these functions when using double buffering, except if your swap-buffers implementation doesn't automatically flush the commands.