We are seeing posix_fallocate fail with ENOENT occasionally.
This shouldn't happen according to the docs, but it does. Fall back
to ftruncate if it does. It gives us less guarantees, but it makes
the ci not fail so much.
Due to the way the intermediate offscreen gets drawn, we might end up
with seams at the edges.
And I don't think it's worth spending more time on than saying "not
opaque".
Fixes the compare-render testsuite
New testcase included.
We want to operate with opacities, so it makes sense to have this radily
available.
And we're doing a walk over all children on creation anyway, so why not
just capture the rect there.
We want to be able to express opaque grids. This means that the app
provides either a row of columns of opaque nodes or a column of rows,
and then the containers will magically figure it out.
The main use case for this is terminals, which are uilt using cells. And
when there's a transparent background configured but the contents are
opaque, it'd be nice if we could figure that out.
Also remove the 80% requirement. It is rather arbitrary and while it
helps for some cases, the aforementioned grid would suffer.
Clip nodes often appear in the widget tree.
And the implementation can be trivial because of the sanity checks
already performed before calling the vfunc.
This is required because transform nodes appear everywhere.
We just exit for all transforms that can't transform the clip rect
losslessly. Both because they are rare and because we'd make the
coverage possibilities much lower.
Containers can walk the list of children back to front, trying to find
the topmost node that fully covers the viewport.
And then they can skip drawing all the nodes before that one.
Asks a node to add itself if it is fully covering the clip rectangle.
In that case, it is the first node that needs to be added.
If the node is not fully covering the clip, it should not draw itself,
because there might be stuff needing to be drawn below.
If a node adds itself, it should call gsk_gpu_render_pass_begin_op().
We find the first child that covers >80% of the container and return
that.
This is a nice speedup for the common case of a GtkWindow being covered
by a large opaque background.
It will fall apart for fancy themes that play with transparency or for
small windows because the shadow region gets too large.
But then we just scan the whole node tree.
We could think about adapting the 80% number, because that wasn't chosen
with any real scientific data behind it.
This takes both the vertical and horizontal rectangle that isn't
covering the rounded corners and intersects both with the child's opaque
rect.
And then it returns the larger of the two.
This means the small slices of a window near the left/right (or
top/bottom) will never be covered, but if we wanted that, we'd need to
use something else than a rectangle - either a region or actually a
rounded rect.
But that is a lot more expensive to implement.
Tests are node files dumped into testsuite/gsk/opaque
They are named "name-X-Y-W-H.node" with X Y W H being the expected
opaque rectangle or "name.node" if there is no opacity.
A simple example is included here.
We can in fact meet complex transforms here. Asserting that they
are simple doesn't make it so. Instead, simply bail out if a
transform is too complex; in this case we can't offload anyway,
so no need to walk the tree further.
Test included.
Fixes: #6824
We wanted premultiplied images in all cases anyway, and moving that
requirement means we can also move the caching code for re-caching
textures into the texture specific code.
This uses offscreens for every call to get_node_as_image().
This is useful both for benchmarking benefits of those implementations
as well as checking that the node-specific paths produce identical
results.
gsk_gpu_node_processor_ensure_image() was a weird amalgamation of stuff
withe weird required and disallowed flags.
Refactor it to make the two operations we actually do there more
explicit: Removing straight alpha and generating mipmaps.
This untangling is also desirable in the future when we also want to
handle colorstates here.
Always return premultiplied images.
2 fallback cases for clip and transform nodes did not require that. If
those cases turn out to be important, they can call
gsk_gpu_get_node_as_image() directly as that's the more flexible option.
Pass through to the child instead of offscreening.
I mainly implemented it for the assertion, because this might be a
sneaky way to introduce bugs without exhaustive checking that we don't
offload stuff that is offscreened.
No actual bugs that I'm aware of, so no tests.
Strictly defensive coding.
When getting a texture as image, we were always returning the texture
unconditionally.
However, we want to mipmap textures when the scale factor is too large,
and this code path did not do that.
The same codepath on the GL renderer doesn't do that either, so the test
is disabled for it.
The switch statement was ugly.
Plus, the code should be close to the add_node() vfunc implementation,
so they can be modified together.
See future commits for an example where this matters.
