Desktop OpenGL implements a GL_FRAMEBUFFER_SRGB setting; query that instead
of the frambuffer color encoding.
With this change it is no longer necessary to enable FRAMEBUFFER_SRGB
in the macOS setup; remove it.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
macOS is the only platform where desktop OpenGL is used. To support
foreign ANGLE contexts add a setting to override Gio's selection of
OpenGL implementation.
The bulk of this change is making all function pointers per-context
instead of global, and loading the OpenGL library dynamically. As a side
effect we're closer to Gio tolerating a platform without any OpenGL
implementation. For example, Apple has deprecated OpenGL and OpenGL ES
on its platforms and may remove them in the future.
Note that as a side-effect of this change, Gio needs Go 1.16 or newer to
run on iOS.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
Programs such as gio-example/glfw rely on Gio drawing blending with
the framebuffer background. This change makes it so when sRGB emulation
is active.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
The reflected uniform names are for the shader versions that don't use uniform
buffer objects. For UBO shaders, the names won't resolve.
This change adds a panic when shader uniforms are not found, and fixes
Fixes gio#216
Signed-off-by: Elias Naur <mail@eliasnaur.com>
Elias Naur