commit 44e8451cd9 ("render/gles2: hide shm formats without GL
support") added the is_gles2_pixel_format_supported() function to
render/gles2/pixel_format.c, whose stated purpose is to "check whether
the renderer has the needed GL extensions to read a given pixel format."
It then used that function to filter the pixel formats returned by
get_gles2_shm_formats().
The result of this change is that RGB formats are no longer reported for
GL drivers that don't implement EXT_read_format_bgra, even when those
formats are supported for rendering (which they have to be for
wlr_gles2_renderer_create() to succeed). This is a pretty clear
regression, since wlr_renderer_init_wl_shm() fails when either of
WL_SHM_FORMAT_ARGB8888 or WL_SHM_FORMAT_XRGB8888 are missing.
To fix the regression, change is_gles2_pixel_format_supported() to
accept all pixel formats that support rendering, regardless of whether
we can read them or not, and move the check for EXT_read_format_bgra
back into gles2_read_pixels(). (There's already a check for this
extension in gles2_preferred_read_format(), so we're not breaking any
abstraction that wasn't already broken.)
Tested on the NVIDIA 495.46 proprietary driver, which doesn't support
EXT_read_format_bgra.
Fixes: 44e8451cd9 ("render/gles2: hide shm formats without GL support")
Thomas Hebb
59b9518f07