Add an implementation of GdkDmabufDownloader that uses
gsk_renderer_render_texture + GL texture download.
Since gsk isn't threadsafe, we do the download in the main thread,
taking care to not disturb the current GL context of whatever is
going on there at the time.
And since gsk renderers are expensive to create, we cache it
in the display.
Note that gsk does not yet have any special support for
dmabuf textures, so for now, they will always get downloaded
and then reuploaded as GL textures.
This is a simple helper that feed a GdkTexture
through a renderer and returns the resulting
texture. This will be used to convert dmabuf
textures to 'native' textures.
Trying to use it is a programming error, applications should have code
that uses real modifiers.
Also add a check to the formatsbuilder so our code doesn't include the
invalid modifier by accident.
We don't really know how to deal with it, so better force applications
to figure out what to do.
When adding the formats of a downloader, allow them to return FALSE to
mean "This method is not supported", which is a useful way to opt out
when checking GL or Vulkan extensions and finding out that the desired
one isn't supported.
The code now by default puts all planes into the same fd - like
v4l does, too.
The old behavior of one fd per plane can be enabled via --disjoint.
Also, am --undecorated option has been added so that the window
isn't decorated and all that the renderer has to do is display the
dmabuf.
This is useful when debugging just the dmabuf rendering.
This seems to be what everyone does, so we should do it, too.
Previously it was assumed that an fd of -1 would mean reusing the
previous fd with a different offset, but that seems to be uncommon.
This uses the dma-heap kernel api to create a dma-buf
and use it for a GdkDmabufTexture. It supports a few
formats to test how well GL conversion of YUV works.
The YUV code is adapted from weston tests.
We did have 4 ordering variations of ARGB straight,
but only 3 premultiplied. Add the missing one.
Update all the places where we switch over memory formats.
1. Split out the download function from the mmap'ing of the plane(s)
2. Make the code mmap() all the planes
3. Determine size using lseek() as documented by libdrm, instead of
trying to guess it from the format.
4. Fix some bugs, like switcheroos of width and height
Tries to sanitize the dmabuf to conform to the values expected
by Vulkan/EGL which should also be the values expected by
Wayland compositors
We put these sanitized values into the GdkDmabufTexture, by
sanitizing the input from GdkDmabufTextureBuilder, which are
controlled by the callers.
Things we do here:
1. Disallow any dmabuf format that we do not know.
1. Treat the INVALID modifier the same as LINEAR.
2. Ignore all other modifiers.
3. Try and fix various inconsistencies between V4L and Mesa,
like NV12.
*** WARNING ***
This function is not absolutely perfect, you do not have a
perfect dmabuf afterwards.
In particular, it doesn't check sizes.
