Makes the verbose output (a lot) more verbose, but it makes the
colorstates used in the shaders very visible.
And it will be relevant once people start using different colorstates
everywhere (like oklab for gradients/colors and so on).
This adds the following functions:
output_color_from_alt()
alt_color_from_output()
Converts between the two colors
output_color_alpha()
alt_color_alpha()
Multiplies a color with an alpha value
This adds a GdkColorStates that encodes 2 of the default GdkColorStates
and wether their values are premultiplied or not.
Neither do the shaders do anything with this information yet, nor do the
shaders do anything with it yet, this is just the plumbing.
If desired, try creating GL_SRGB images. Pass a try_srgb boolean down to
the image creation functions and have them attempt to create images like
that.
When it is not possible to create srgb images in the given format, just
fall back to regular images. The calling code is meant to check the
GSK_GPU_IMAGE_SRGB flags to determine the actual format of the resulting
image.
Make the node processor and the pattern writer track the current
compositing color state. Color state nodes change it. We pass
the surface color state down via the frame apis.
The name of the variable is "ccs" for "compositing color space". It's an
unused variable name and it's common enough to deserve a short and sweet
name.
This shader converts between two color states, by using the
same functions that we use on the cpu. The conversion to perform
is passed as part of the variation.
As premultiplication is part of color states on the shader, we also
encode the premultiplication in the shader.
And because opacity is a useful optimization, we also allow setting
opacity.
For now, the only possible color states are srgb and srgb-linear.
This adds the following:
- ccs argument to GskRenderNode::draw
This is the compositing color state to use when drawing.
- make implementations use the CCS argument
FIXME: Some implementations are missing
- gsk_render_node_draw_with_color_state()
Draws a node with any color state, by switching to its compositing
color state, drawing in that color state and then converting to the
desired color state.
This does draw the result OVER the previous contents in the passed in
color state, so this function should be called with the target being
empty.
- gsk_render_node_draw_ccs()
This needs to be passed a css and then draws with that ccs.
The main use for this is chaining up in rendernode draw()
implementations.
- split out shared Cairo functions into gdkcairoprivate.h
gskrendernode.c and gskrendernodeimpl.c need the same functions.
Plus, there's various code in GDK that wants to use it, so put it in
gdk/ not in gsk/
gsk_render_node_draw() now calls gsk_render_node_draw_with_color_state()
with GDK_COLOR_STATE_SRGB.
That's basically the "undefined" value. We need that when drawing
nothing, which so far only happens with empty container nodes.
But empty container nodes can be children of other nodes, and that makes
things propagate. So instead of catching them, force the whole rest of
the code to deal with an undefined depth.
We also can't just set a random depth, because that will cause merging
to fail.
This is an experiment for now, but it seems that encoding srgb inside
the depth makes sense, as we not just use depth to decide on the
GL fbconfigs/Vulkan formats to pick, depth also encodes how the [0...1]
color values are quantized when stored.
Let's see where this goes.
This commit just adds the flag, but I wanted to make it an individual
commit to explain the purpose:
The SRGB flag is meant to be used for images that have an SRGB format.
In Vulkan terms, that means VK_FORMAT_*_SRGB.
In GL, it means GL_SRGB or GL_SRGB_ALPHA.
As these formats have been madatory since GL 3.0, we can (ab)use them
uncoditionally. Images in these formats are renderable, too, so it's
not just usable for uploading.
What these images allow is treating the data as sRGB while shaders
access them as linear, thereby getting sRGB<=>linear conversions for
free.
It is also possible to switch off the linearization of these images and
treat them as sRGB, which allows all sorts of shenanigans, though one
has to be careful if that turning off applies to the relevant GL/Vulkan
code in question.
If the GL texture is exportable to a dmabuf, we can just use our dmabuf
importing code to get that texture into Vulkan.
There is no need to go via host memory in that case.
And if it doesn't work, we just fall back, like before.
Unimplemented nodes are a failure now.
We make this a soft failure with a g_warning() so that during
development when adding new nodes, the renderer doesn't instantly crash,
but instead prnts a warning.
But we do consider unimplemented nodes a bug now.
Because of that, add_fallback_node() is now renamed to add_cairo_node().
When determining which way is up for the offloaded texture, we
must take all transforms into account - the ones outside the
subsurface node, and the ones inside.
By moving negative affines to be treated like dihedrals, because they
also need support of the modelview, we can free up the affine branch for
doing work without it.
Not a big win I guess, but it makes scaling more efficient.
This allows handling them without ever needing to offscreen for losing
the clip, because the clip can always be transformed.
Also, all the optimizations keep working, like occlusion culling,
clears, and so on.
The main benefit of this work is the ability for offloading to now
handle dihedral transforms of the video buffer.
The other big advantage is that we can now start our rendering with a
dihedral transform from the compositor.
This category does a finer-grained categorization than
GskTransformCategory, but it is deliberatedly made to allow
easy backwards compatibility.
The reason for the categories is that they fit our renderers more
fine.
In particular, it allows implementing wl_output_transform support more
efficiently, thereby allowing rendering buffers the right way for
rotated phone screens or monitors.
The rectangles need to touch/overlap in both directions, otherwise
there's no coverage that covers both rectangles.
Test included.
Fixes rendering glitches in various apps when redrawing.
Fixes: #6849
... instead of init_draw(); add_node(); finish_node();
We hook into the infrastructure one step earlier and close to where the
default renderer_render() and renderer_render_texture() arrive in the
nodeprocessor.
Why is this relevant?
Because process() does occlusion culling.
TL;DR: offscreens do culling now
We import them as general, so they should be exported like that.
This was a longstanding issue that I never got around to fixing and I'm
touching this code anyway atm.
See commit 3aa6c27c26 for more details.
NULL disables clearing. We only implement this for GL as in Vulkan we'd
need to create different renderpasses with different attachment
descriptions and that would require more plumbing.
We need to check that the clip is inside the opaque region, not that the
opaque region is inside the clip.
Test included, using the only not that hits the fallback path with an
opaque region smaller than its bounds.
Sometimes container nodes contain lots of overlapping opaque items. In
that case we can use the container node itself as the first node even
though none of the children cover the whole paint area.
The use case for this is a grid of cells like in a terminal where all
the cells are opaque and we want to avoid drawing the background behind
them.
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.
