UNDEFINED when used as source layout means that the contents of
the underlying memory becomes undefined. This isn't what we want
here: we don't want to mutate the imported pixel data.
The Vulkan spec isn't really clear what the proper value should be
here, but after discussing with driver developers [1] it seems like
UNDEFINED isn't the right one. The recommendation is to use GENERAL
instead.
[1]: https://github.com/ValveSoftware/gamescope/issues/356
This change makes it possible to support both the direct srgb-format
pipeline and indirect (color-managed, or non-srgb-format) pipeline
for the same render buffer.
Pre-multipled sRGB values need to be un-multiplied before conversion
to linear and then re-multiplied after. Compare shaders/texture.frag.
This fixes an issue in labwc where titlebar corners (rendered as
ARGB textures) did not match the rest of the titlebar (rendered as
a solid wlr_scene_rect).
Note: 0.17 has other instances in render/vulkan/renderer.c that need
the same fix.
If the compositor were to try to handle a GPU reset within the lost
signal (by recreating the renderer) we should avoid referencing renderer
resources after the lost signal. This prevents use after free for such
compositors.
Simon Ser
Kirill Primak
Manuel Stoeckl
John Lindgren
Alexander Orzechowski