Instead of using an enum, use a usual custom class struct like we use
for GskGpuOp.
As a side effect of that refactoring, the display gained a hash table
for textures where we can't use the render data because the texture is
used in multiple renderers.
The goal here is that a texture is always cached and we can ensure that
there is a 1:1 relation between textures and their GskGpuImage. This is
important in particular for external textures - like dmabufs - where we
absolutely don't want 2 images with 2 device memories, and where we use
toggle references to keep them alive.
Reserve 3 texture units per immutable sampler (because that's the
maximum per YUV sampler).
Ensure that the max-sampler calculations always include the immutable
samplers, too.
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.
Shader compilers struggle with compiling code that indexes texture
arrays by indexes, so keep the fallback shaders simple and don't do that
there.
There's not much of a performance difference anyway between those two
methods.
In the case where descriptor indexing is not enabled and the number of
max images is small (or we use extensive amounts of immutable samplers),
we need to be able to switch descriptors.
This patch makes that possible.
We compile custom shaders for Vulkan 1.0 that don't require the
extension.
We also ensure that our accesses are uniform by only executing one
shader at a time.
Let the objects track the number of samplers or buffers needed.
This is a required step for making Vulkan work with less featureful
(read: mobile) implementations.
This is relevant went encountering repeat nodes, where the repeat cutoff
will make the fwidth of the position go wild otherwise.
Gradients require more work now, because we need to compute offsets
twice - once for the pixel, once for the offst.
Carry an n_external_textures variable around when selecting programs and
compile different programs for different amounts of external textures.
For now, this code is unused, but dmabufs will need it.
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.
There's a well hidden line in the spec that says in
https://registry.khronos.org/vulkan/specs/1.3/html/chap15.html#interfaces-resources-descset
If the combined image sampler enables sampler Y′CBCR conversion,
it **must** be indexed only by constant integral expressions when
aggregated into arrays in shader code, irrespective of the
shaderSampledImageArrayDynamicIndexing feature.
So we'll use the same trick that we use for old GL here and do an
if dance that gives us dynamically uniform expressions.
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.
Define an array with a compile-time-constant variable size for the
immutable samplers.
A bunch of work is necessary to ensure that at least one element is in
the sampler array, because the GLSL code
sampler2D immutable_textures[0];
is invalid.
This allows having different layouts sothat we can support immutable
samplers, whcih are required for multiplane and YUV formats.
We don't use them yet.
use it to collect the optional features we are interested in and turn
them on only if available.
For now we add the dmabuf features, but we don't use them yet.
The main reason here is that we want to not fail when the texture size
is larger than the supported GpuImage size.
When that happens, for now we just fallback slowly - ulitmately to
drawing with Cairo, which is going to be clipped.
