Re: [pygame] erratic behavior with 'display.update(Rect)'

To: "pygame-users@xxxxxxxx" <pygame-users@xxxxxxxx>

Subject: Re: [pygame] erratic behavior with 'display.update(Rect)'

From: Ian Mallett <ian@xxxxxxxxxxxxxx>

Date: Mon, 13 Jul 2015 17:49:51 -0700

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On Mon, Jul 13, 2015 at 5:34 PM, Tom Rothamel <tom@xxxxxxxxxxx> wrote:

There isn't a way to update a portion of the display using OpenGL. OpenGL expects you to redraw the screen from scratch every frame, and then flip to the next frame.

How are you drawing to the screen? Are you using GL calls? Or pygame blits to the screen surface? The later doesn't work with OPENGL.

âYes and:

Is it possible that the cause is that OPENGL is being used by pygame?

On Windows, afaik, this only happens if you request it with the pygame.OPENGL flag. Nevertheless, inspecting the value of the following should say for sure:

import os
print(os.environ["SDL_VIDEODRIVER"])

Pro-tip: IIRC, you can also set that value to whatever you like before you initialize PyGame. Some values.

Ian