vo_gpu: vulkan: use libplacebo instead

This commit rips out the entire mpv vulkan implementation in favor of
exposing lightweight wrappers on top of libplacebo instead, which
provides much of the same except in a more up-to-date and polished form.

This (finally) unifies the code base between mpv and libplacebo, which
is something I've been hoping to do for a long time.

Note: The ra_pl wrappers are abstract enough from the actual libplacebo
device type that we can in theory re-use them for other devices like
d3d11 or even opengl in the future, so I moved them to a separate
directory for the time being. However, the rest of the code is still
vulkan-specific, so I've kept the "vulkan" naming and file paths, rather
than introducing a new `--gpu-api` type. (Which would have been ended up
with significantly more code duplicaiton)

Plus, the code and functionality is similar enough that for most users
this should just be a straight-up drop-in replacement.

Note: This commit excludes some changes; specifically, the updates to
context_win and hwdec_cuda are deferred to separate commits for
authorship reasons.

1 files changed, 7 insertions, 4 deletions

diff --git a/wscript b/wscript
index d3d49090c8..09eb5da529 100644
--- a/wscript
+++ b/wscript
@@ -805,11 +805,14 @@ video_output_features = [
                 "Aborting. If you really mean to compile without OpenGL " +
                 "video outputs use --disable-gl.",
     }, {
+        'name': '--libplacebo',
+        'desc': 'libplacebo support',
+        'func': check_pkg_config('libplacebo >= 1.18.0'),
+    }, {
         'name': '--vulkan',
-        'desc': 'Vulkan context support',
-        'deps': 'shaderc',
-        # Lowest version tested, Ubuntu 16.04's
-        'func': check_pkg_config('vulkan >= 1.0.61'),
+        'desc':  'Vulkan context support',
+        'deps': 'libplacebo',
+        'func': check_pkg_config('vulkan'),
     }, {
         'name': 'egl-helpers',
         'desc': 'EGL helper functions',