Bug 98310

Summary:	GLES context returned by OpenGL API
Product:	Mesa	Reporter:	Cedric Sodhi <manday>
Component:	EGL	Assignee:	mesa-dev
Status:	RESOLVED NOTOURBUG	QA Contact:	mesa-dev
Severity:	major
Priority:	medium
Version:	git
Hardware:	Other
OS:	All
Whiteboard:
i915 platform:		i915 features:

Description Cedric Sodhi 2016-10-18 15:01:51 UTC

The ultimate consequence of this bug is that EPoxy thinks that the current context is OpenGL, although it is GLES2. It reports this up to GTK/GDK which then abandones GLES2 rendering (because it thinks OpenGL is being used).

EPoxy tests whether the current context is OpenGL by

epoxy_egl_get_current_gl_context_api( )

in two steps, by first binding the API which is being tested for:

eglBindAPI( EGL_OPENGL_API );

and subsequently testing for a context

if( eglGetCurrentContext( ) ) ...

I don't know whether this is actually a proper way of testing this (or why this is required by further up in the first place), but I can definitely say I do NOT have OpenGL (simply because of the lack of X11 libraries and I built Mesa only with GLES2) but that call, after the OPENGL_API was bound, returns a context. Which in turn makes Epoxy think that the context is OpenGL.

Comment 1 Adam Jackson 2016-10-18 15:12:48 UTC

Mesa is right, epoxy is wrong:

https://github.com/anholt/libepoxy/pull/90

Comment 2 Chad Versace 2016-10-18 15:22:14 UTC

Related bug on the real libepoxy bugtracker: https://github.com/anholt/libepoxy/issues/25

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