Color transform can have multiple types and these different types
want to store different metadata. We previously stored this metadata
directly on wlr_color_transform even for transforms that don't use it.
Instead, let's take the prior art from wlr_scene where each scene node
is built on a base node. Notice how wlr_color_transform_lut3d now has
a `struct wlr_color_transform base`. This is advantageous in multiple
ways:
1. We don't allocate memory for metadata that will never be used.
2. This is more type safe: Compositors can pass around a
struct wlr_color_transform_lut3d if they know they only want to use a
3d_lut.
3. This is more scalable. As we add more transform types, we don't have
to keep growing a monolithic struct.
This change makes it possible to support both the direct srgb-format
pipeline and indirect (color-managed, or non-srgb-format) pipeline
for the same render buffer.
Instead of having separate getters for shm formats and DMA-BUF
formats, use the same pattern as wlr_output_impl.get_primary_formats
with a single function which takes buffer caps as input.
Saving the old context and immediately making our own context
current is a common pattern. Let's make it easier to do.
No functional change, just refactoring.
Since we only use the backend capabilities here we can simply pass
them in directly. This allows other locations to create an allocator
even if they don't have a backend. They can simply specify the caps
they want instead.
Some opaque pixel formats (nv12, p010) require per-plane bytes_per_block
info. However, it doesn't make sense to store them in
wlr_pixel_format_info, as they will never be useful (currently, this
info is used for shm, which doesn't have a concept of multi-planar
buffers.)
Let's define a separate array and function for determining whether a
pixel format has alpha.
This is the last of a set of commits which ensures that both textures
and render buffers can be accessed through _UNORM and _SRGB image
views. While _UNORM image views are not yet used for 8-bpc image
formats, they will be needed in the future to support color transforms
for both textures and render buffers.
These comments were a bit misleading:
- "GL_TEXTURE_2D == mutable": not really, imported non-external-only
DMA-BUFs would also use this target, but are not mutable.
- "Only affects target == GL_TEXTURE_2D": same here.
- "If imported from a wlr_buffer": not really, would be NULL if
imported from a shm wlr_buffer.
Adjust these comments to better reflect reality and adjust the check
in gles2_texture_update_from_buffer().
We can double import a dmabuf if we use it as a texture target and
a render target. Instead, let's unify render targets and texture dmabuf
imports to use wlr_gles2_buffer which manages the EGLImageKHR
This will become necessary when we switch away from scissoring. For the
time being, this cleans things up a bit and allows for a trivial
blending implementation for textures when that comes.
