We now handle the case where memory is not HOST_CACHED.
We also track the memory type now so we can avoid mapping image memory
that is not HOST_CACHED and use buffer transfers instead.
This adds GSK_GPU_IMAGE_CAN_MIPMAP and GSK_GPU_IMAGE_MIPMAP flags and
support to ensure_image() and image creation functions for creating a
mipmapped image.
Mipmaps are created using the new mipmap op that uses
glGenerateMipmap() on GL and equivalent blit ops on Vulkan.
This is then used to ensure the image is mipmapped when rendering it
with a texture-scale node.
Add a GSK_GPU_IMAGE_STRAIGHT_ALPHA and use it for images that have
straight alpha.
Make sure those images get passed through a premultiplying pass with
the new straight alpha shader.
Also remove the old Postprocess flags from the Vulkan image that were a
leftover from copying that code from the old Vulkan renderer.
This now uses all the previously added features to allow displaying YUV
images.
Also add a utility function that turns an image into a toggle ref for a
texture. This makes sure that reffing the image also refs the texture
and that ensures that textures stay alive as long as the image is in
use.
For now, the flags are just there because, and nobody uses them yet.
The only flag is EXTERNAL, which for now I'm using for YUV buffers,
though it's a bit undefined what that means.
Images can now have samplers - meaning they must be rendered with that
sampler. It also means that sampler must be handled as an immutable
sampler in descriptorsets.
These samplers can be created with a samplerYcbcrConversion, so code has
been added to pass that conversion when creating the imageview.
Also add code to GskVulkanFrame to track immutable samplers.
Nobody is making use of this yet.
... and use it to initialize the "proper" projection matrix to use in
shaders.
The resulting viewport will go from top left (0,0) to bottom right
(width, height) and the z clipping plane will go from -10000 to 10000.
This heaves over an inital chunk of code from the Vulkan renderer to
execute shaders.
The only shader that exists for now is a shader that draws a single
texture.
We use that to replace the blit op we were doing before.
For now, it just renders using cairo, uploads the result to the GPU,
blits it onto the framebuffer and then is happy.
But it can do that using Vulkan and using GL (no idea which version).
The most important thing still missing is shaders.
It also has a bunch of copy/paste from the Vulkan renderer that isn't
used yet.
But I didn't want to rip it out and then try to copy it back later
