This makes sure that we don't have cursors disappearing on Windows upon
scrolling because we can't find a cursor that exists on the system during
a scroll, and unlike GTK-3.x, we do not default to the arrow pointer on GTK4.
Just mimic what we have on X11 and Wayland: the trusty standard arrow pointer.
Fixes issue #3581.
We were calling _gdk_surface_update_size() every frame, even if the
window size didn't change. This would cause us to discard all cached
buffers and redraw the whole screen.
This was BAD.
Recognize a common pattern: A rounded clip with
a color node, followed by a border node, with the
same outline. This is what CSS backgrounds frequently
produce, and we can render it more efficiently with
a combined shader.
Now that colors aren't uniforms anymore, we don't
win much by using the inset_shadow shader. The fragment
shaders of inset_shadow and border are identical. And
the regular border setup does nine-slicing.
Colors are not state that we carry across draw ops,
so setting the color on the render job doesn't make
much sense. Instead, pass the color to the various
draw calls. Add a few new ones for that purpose.
Also, shorten the names of some by going from
'load_vertices_from_offscreen' to 'draw_offscreen'.
Don't place the insertion cursor render nodes in the
middle of the text nodes for all the text. This helps
the renderer batching the text draw calls together.
This reduces how many changes we make when recording uniform state, which
increases the chances that the data offset will be the same when applying
uniforms.
Since we make full snapshots when recording uniform state of batches, we
need to perform some deduplication to avoid so many repeated uniform calls.
This uses a closed hashtable to determine if we are likely changing the
value to something new.
This does not currently compare values, it instead only compares that we
are going to point at a new offset into the uniform buffer. We could go
further if we compare upon updating values (we did that early on in the
prototype) so that offsets are less likely to be changed.
When the color passed is transparent black, use
the color from the texture as source, instead of
as mask. This lets use use the coloring program
both for regular and color glyphs, avoiding
program changes in text with Emoji.
Instead of using uniforms for color used in multiple
programs, pass it as vertex attributes. This will let
us batch more draw calls, since we don't have to change
uniforms so often. In particular, for syntax-highlighted
text.
We may want to change the interface between the
shaders and the renderer for ngl, and therefore,
sharing the shaders between gl and ngl will not
be practical, going forward.
