Opened 2 years ago

Closed 21 months ago

#13215 closed defect (fixed)

OpenGLSdlGraphics3dManager::setupScreen() might invoke `glGetIntegerv` without GL context

Reported by: GMTA Owned by: lephilousophe
Priority: low Component: Common
Version: Keywords:
Cc: Game: Grim Fandango

Description (last modified by GMTA)

When switching from the launcher to an OpenGL game such as Grim Fandango, the GL context is destroyed and then created again. To create a new context, OpenGLSdlGraphics3dManager::setupScreen() is invoked. Before it actually created a new context, the MSAA sample count is retrieved with:

SDL_GL_GetAttribute(SDL_GL_MULTISAMPLESAMPLES, &currentSamples);

This in turn invokes glGetIntegerv. According to the OpenGL spec, invoking any API without an active GL context results in undefined behavior.

While porting ScummVM to SerenityOS, I have had to patch out the above call to make Grim Fandango work at all. This is not a fix but a workaround, but it might be useful for you to see.

A possible solution would be to make sure to only retrieve the samples when a GL context exists.

Related SerenityOS PR:

Attachments (1)

0001-Prevent-call-to-glGetIntegerv-without-context.patch (1.2 KB ) - added by GMTA 2 years ago.

Download all attachments as: .zip

Change History (3)

comment:1 by GMTA, 2 years ago

Description: modified (diff)

comment:2 by lephilousophe, 21 months ago

Owner: set to lephilousophe
Resolution: fixed
Status: newclosed
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