Switch symbolc icon drawing from color-matrix to mask nodes
make the performance of the iconscroll demo crater (from 60fps
to 10fps).
Apply the same optimization we already have for color-matrix
nodes when drawing mask nodes. This gets us back to 60fps.
Fixes: #6700
This works better for cff fonts, where hinting is not as local as
what the autohinter does for ttf fonts, and it does not seem to
have negative effects.
Fixes: #6577Fixes: #6568
When we get an unhinted font for text node extents, don't change
the antialiasing setting. It doesn't affect the extents we get
here, but if we later need an unhinted font for rendering, the
one we create this way will be the right one, so it will already
exist.
We need precise bounds. And while hinting might shift the rendering
around from these bounds by a fraction of a pixel, we account for
this in the places where it matters: when determining diff regions,
when sizing offscreens, and when determining the size of atlas
regions for glyphs.
We lost this when a bunch of rect code was inlined in
commit 36314f28e2, and as it turns out, that broke some
applications. So, bring it back.
Fixes: #6435
We can just check if the subsurfaces contain content - and if they do,
they will be offloading and we can ignore the diff.
This essentially reverts 48740de71a
Instead of relying on diffing subsurface nodes, we track damage
generated by offloaded contents inside GskOffload.
There are 3 stages a subsurface node can be in:
1. not offloaded
Drawing is done by the renderer
2. offloaded above
The renderer draws nothing
3. offloaded below
The renderer needs to punch a hole.
Whenever the stage changes, we need to repaint.
And that can happen without the subsurface's contents changing, like
when a widget is put above the subsurface and it needs to to go from
offloaded above to below.
So we now recruit GskOffload for tracking these changes, instead of
relying on the subsurface diffing.
But we still need the subsurface diffing code to work for the
non-offloaded case, because then the offloading code is not used.
So we keep using it whenever that happens.
Not that when a subsurface transitions between being offloaded and not
being offloaded, we may diff it twice - once in the offload code and
once in the node diffing - but that shouldn't matter.
When a subsurface goes from not offloaded to offloaded (or vice versa),
we need to add the whole node to the diff region, because we switch from
whatever contents were drawn to a punched hole.
A PangoFont keeps a weak reference to its fontmap. In addition,
keep a strong reference in GskTextNode, so we can be sure that
custom font maps won't go away before the node is finalized.
These are not usable outside of GTK, so lets not burden bindings
with them.
I'll keep the get_child() function exposed, since it is needed to
iterate over node trees containing subsurface nodes.
This is mostly untested and a result of reading the code.
The main effect here happens when a node was drawn that didn't start on
an integer boundary, which is very rare.
However, with specially crafted tests and when using fractional scaling,
this can happen.
This happened most often when clipping by the node bounds to restrict a
push_group() call. Enlarge that rectangle to fall on a pixel boundary.
Use it to overlay an error pattern over all Cairo drawing done by
renderers.
This has 2 purposes:
1. It allows detecting fallbacks in GPU renderers.
2. Application code can use it to detect where it is using Cairo
drawing.
As such, it is meant to trigger both with cairo nodes as well as when
renderers fallback for regular nodes.
The old use of the debug flag - which were 2 not very useful print
statements - was removed.
Mask nodes are transparent outside of the intersection of source and
mask, unless the mask ode is inverted alpha.
Set the bounds accordingly.
Tests have been updated accordingly.
This is the result of experimenting with corner cases when blurring.
The result is a test that tests when the child of a blur node is
clipped out but the blurred child is not, the blurred parts are still
visible.
This immediately broke the cairo renderer, so the fix is included.
Add an extra argument to pass offload info to the diffing code.
This is then used for diffing subsurface nodes differently,
depending on their offloading status.
When shadows were offset - in particular when offset so the original
source was out of bounds of the result - the drawing code would create a
pattern for it that didn't include enough of it to compose a shadow.
Fix that by not creating those patterns anymore, but instead drawing the
source (potentially multiple times) at the required offsets.
While that does more drawing, it simplifies the shadow node draw code,
and that's the primary goal of the Cairo rendering.
Test included.
Cairo and the GL renderer have a different idea of how to handle
transitioning of colors outside the defined range.
Consider these stops:
black 50%, white 50%
What color is at 0%?
Cairo would transition between the last and first stop, ie it'd do a
white-to-black transition and end up at rgb(0.5,0.5,0.5) at 0%.
GL would behave as it would for non-repeating gradients and use black
for the range [0%..50%] and white for [50%..100%].
The web would rescale the range so the first stop would be at 0% and
the last stop would be at 100%, so this gradient would be illegal.
Considering that it's possible for code to transition between the
different behaviors by adding explicit stops at 0%/100%, I could choose
any method.
So I chose the simplest one, which is what the GL renderer does and
which treats repeating and non-repeating gradients the same.
Tests attached.
Based on reverse engineering the color node and contrary to my
expectations, the matrix/offset is expressed in, and applied to,
unpremultiplied colors. The colors are being explicitly
unpremultiplied, transformed according to the matrix/offset, and
premultiplied back (see color_matrix.glsl). The matrix is getting
transposed.
Also, copy the same blurb to the corresponding GtkSnapshot function.
Signed-off-by: Sergey Bugaev <bugaevc@gmail.com>
