Hardware decoding things often need access to additional handles from
the windowing system, such as the X11 or Wayland display when using
vaapi. The opengl-cb had nothing dedicated for this, and used the weird
GL_MP_MPGetNativeDisplay GL extension (which was mpv specific and not
officially registered with OpenGL).
This was awkward, and a pain due to having to emulate GL context
behavior (like needing a TLS variable to store context for the pseudo GL
extension function). In addition (and not inherently due to this), we
could pass only one resource from mpv builtin context backends to
hwdecs. It was also all GL specific.
Replace this with a newer mechanism. It works for all RA backends, not
just GL. the API user can explicitly pass the objects at init time via
mpv_render_context_create(). Multiple resources are naturally possible.
The API uses MPV_RENDER_PARAM_* defines, but internally we use strings.
This is done for 2 reasons: 1. trying to leave libmpv and internal
mechanisms decoupled, 2. not having to add public API for some of the
internal resource types (especially D3D/GL interop stuff).
To remain sane, drop support for obscure half-working opengl-cb things,
like the DRM interop (was missing necessary things), the RPI window
thing (nobody used it), and obscure D3D interop things (not needed with
ANGLE, others were undocumented). In order not to break ABI and the C
API, we don't remove the associated structs from opengl_cb.h.
The parts which are still needed (in particular DRM interop) needs to be
ported to the render API.
The testing_only field is not referenced anymore with vaglx removed and
the previous commit dropping all uses.
The ra_hwdec_driver.api field became unused with the previous commit,
but all hwdec interop drivers still initialized it.
Since this touches highly OS-specific code, build regressions are
possible (plus the previous commit might break hw decoding at runtime).
At least hwdec_cuda.c still used the .api field, other than initializing
it.
This is done in several steps:
1. refactor MPGLContext -> struct ra_ctx
2. move GL-specific stuff in vo_opengl into opengl/context.c
3. generalize context creation to support other APIs, and add --gpu-api
4. rename all of the --opengl- options that are no longer opengl-specific
5. move all of the stuff from opengl/* that isn't GL-specific into gpu/
(note: opengl/gl_utils.h became opengl/utils.h)
6. rename vo_opengl to vo_gpu
7. to handle window screenshots, the short-term approach was to just add
it to ra_swchain_fns. Long term (and for vulkan) this has to be moved to
ra itself (and vo_gpu altered to compensate), but this was a stop-gap
measure to prevent this commit from getting too big
8. move ra->fns->flush to ra_gl_ctx instead
9. some other minor changes that I've probably already forgotten
Note: This is one half of a major refactor, the other half of which is
provided by rossy's following commit. This commit enables support for
all linux platforms, while his version enables support for all non-linux
platforms.
Note 2: vo_opengl_cb.c also re-uses ra_gl_ctx so it benefits from the
--opengl- options like --opengl-early-flush, --opengl-finish etc. Should
be a strict superset of the old functionality.
Disclaimer: Since I have no way of compiling mpv on all platforms, some
of these ports were done blindly. Specifically, the blind ports included
context_mali_fbdev.c and context_rpi.c. Since they're both based on
egl_helpers, the port should have gone smoothly without any major
changes required. But if somebody complains about a compile error on
those platforms (assuming anybody actually uses them), you know where to
complain.
Runtime untested, because I get this:
[vo/rpi] Could not get DISPMANX objects.
This happened even when building older git versions, and on a RPI image
that hasn't changed in the recent years. I don't know how to make this
POS work again, so I guess if there's a bug in the new code, it will
remain broken.
This does two separate rather intrusive things:
1. Make the hwdec context (which does initialization, provides the
device to the decoder, and other basic state) and frame mapping
(getting textures from a mp_image) separate. This is more
flexible, and you could map multiple images at once. It will
help removing some hwdec special-casing from video.c.
2. Switch all hwdec API use to ra. Of course all code is still
GL specific, but in theory it would be possible to support other
backends. The most important change is that the hwdec interop
returns ra objects, instead of anything GL specific. This removes
the last dependency on GL-specific header files from video.c.
I'm mixing these separate changes because both requires essentially
rewriting all the glue code, so better do them at once. For the same
reason, this change isn't done incrementally.
hwdec_ios.m is untested, since I can't test it. Apart from superficial
mistakes, this also requires dealing with Apple's texture format
fuckups: they force you to use GL_LUMINANCE[_ALPHA] instead of GL_RED
and GL_RG. We also need to report the correct format via ra_tex to
the renderer, which is done by find_la_variant(). It's unknown whether
this works correctly.
hwdec_rpi.c as well as vo_rpi.c are still broken. (I need to pull my
RPI out of a dusty pile of devices and cables, so, later.)
Move multiple GL-specific things from the renderer to other places like
vo_opengl.c, vo_opengl_cb.c, and ra_gl.c.
The vp_w/vp_h parameters to gl_video_resize() make no sense anymore, and
are implicitly part of struct fbodst.
Checking the main framebuffer depth is moved to vo_opengl.c. For
vo_opengl_cb.c it always assumes 8. The API user now has to override
this manually. The previous heuristic didn't make much sense anyway.
The only remaining dependency on GL is the hwdec stuff, which is harder
to change.
TLS is a headache. We should avoid it if we can.
The involved mechanism is unfortunately entangled with the unfortunate
libmpv API for returning pointers to host API objects. This has to be
kept until we change the API somehow.
Practically untested out of pure laziness. I'm sure I'll get a bunch of
reports if it's broken.
The video code can deal fine with feeding software image formats to
hwdec interop drivers. In RPI's case, this is preferable for
performance, working around OpenGL bugs (see RPI firmware issue #666),
and because OpenGL rendering doesn't bring too many advantages due to
RPI supporting GLES 2.0 only.
Maybe a way to force the normal video path is needed later. But
currently, this can be tested by just not loading the hwdec interop
driver.
If you run command-line mpv and set --hwdec to something that does
not load the RPI interop layer, you'll even have to use --hwdec-preload
manually to get it enabled.
This overlay support specifically skips the OpenGL rendering chain, and
uses GL rendering only for OSD/subtitles. This is for devices which
don't have performant GL support.
hwdec_rpi.c contains code ported from vo_rpi.c. vo_rpi.c is going to be
deprecated. I left in the code for uploading sw surfaces (as it might
be slightly more efficient for rendering sw decoded video), although
it's dead code for now.
wm4
Niklas Haas