When using EGL the mesa+nvidia stack are unable to offload 32bit
framebuffers despite having this capability on GLX. In practice the X11
server does not support alpha windows so we dont need the alpha
component in our framebuffer. We previously had alpha specified in our
framebuffer since we do alpha texturing but testing shows this isnt
required for mesa/intel or nvidia drivers and we must pick a 24bit
config for users to enable render offloading for mixed gpu systems.
fixes#6984
Without this we get somewhat misleading errors from later in the
swapchain creation when this fails. This is currently happening for
users attempting to use multi-gpu with prime offloading on nvidia.
When sharing DMA-BUFs it is required the announce the underlying
hardware capabilities via supported modifiers.
Add new device_query_dmabuf_capabilities vfunc to gs_exports and connect it
to the egl implementation stubs in the supported render platforms. Add a new
public method gs_query_dmabuf_capabilities() that calls the vfunc above.
Add new device_query_dmabuf_modifiers vfunc to gs_exports and connect it
to the egl implementation in the supported render platforms. Add a new
public method gs_query_dmabuf_modifiers() that calls the vfunc above.
This adds the drmbuf format as a parameter separate from the obs texture
format that will be used. drmbuf's may have a variety of formats that we
need to pass correctly to get a usable texture which may correspond to
multi-platform texture formats.
Implement device_texture_create_from_dmabuf for EGL/X11 and EGL/Wayland.
The code is shared between them, in a new gl-egl-common.c file.
This is currently limited to a few common RGB(A) formats for now, which
seems to cover most use cases.
DMA-BUF is a widespread Linux buffer sharing mechanism. It is what's
commonly used zero-copy screen sharing by Wayland compositors.
Add a new 'device_texture_create_from_dmabuf' vfunc to gs_exports,
and stub implementations to libobs-opengl. Add a new public method
gs_texture_create_from_dmabuf() that calls this vfunc.
Introduce the EGL/X11 winsys, and use it when the OBS_USE_EGL environment
variable is defined. This variable is only temporary, for future commits
will add a proper concept of platform.
All the EGL/X11 code is authored by Ivan Avdeev <me@w23.ru>.