In some cases, we were creating gigantic intermediate textures
only to clip out a small section afterwards (e.g. in the listbox
example in gtk4-demo). This is wasteful if we apply effects on
the texture, such as blur or color-matrix. So, clip the dimensions
of the intermediate texture with the current clip. To make this
feasible, we move the texture coordinate computation out of the
pipeline setup functions into the node_as_texture function where
this clipping happens.
One extra complication we encounter is that the node might get
clipped away completely. Since Vulkan does not allow to create
empty images, we bail out in this case and not draw anything.
With these changes, the listbox example in gtk4-demo goes from
32M pixels of intermediate texture to 320000.
Instead of having a function with lots of arguments in
GskVulkanRender that we call from GskVulkanRenderPass which
then just calls back into GskVulkanRenderPass, just create
the new render pass object locally, and an api to add it
to the list that GskVulkanRender keeps. This makes it
a lot easier to preserve all the relevant parameters from
the parent render pass.
Move away from the idea of intra-frame sampling, since we only
push samples once per frame, anyway. Instead, make the profiler
keep a rolling average of the last n frames.
Whenever we need a node as a texture, we now start a new render
pass that renders the node into a new intermediate texture, and
set up a semaphore to make the current render pass wait for it.
As part of this reorganization, much of the setup and drawing
code moved from gskvulkanrender.c to gskvulkanrenderpass.c.
Allow to pass in semaphores to wait for before executing
and to signal after executing the command buffer. This
just exposes the capabilities of the underlying Vulkan
api. Update all callers to pass no semaphores, for now.
We will use this in the future.
I've finally figured out the right combination of src and dest
stage and access flags to make all validation warnings go away.
This commit only fixes the direct upload code.
This is another example for a 2-texture shader.
So far, only separable blend modes are implemented.
The implementation is not optimized, with an
if-else cascade in the shader.
We were looking at uninitialized memory here, instead
of the type of the source clip, as we should.
This showed up as mispositioned clip in the first frame
of a crossfade stack transition, and also as overdraw in
sliding stack transitions.
We already move the descriptor set layout out of it,
so we can just as well keep the pipeline layouts in
the render object as well, and get rid of this extra
object. Update all callers.
Instead of doing multiple copy commands with a tiny buffer
for each glyph, we can just batch them all together. This
also avoids the issue of creating multiple barriers for the
same image.
