Arcs were appealing, but they have a fatal flaw: we can't
split our arcs without changing the ellipse they trace.
That could be fixed by adding an extra parameter, but then
it is no longer any better than conics.
So switch back to conics, which have the advantage that they
are used elsewhere.
Add a new curve type for elliptical arcs
and use it for rounded rectangles and circles.
We use the 'E' command to represent elliptical
arcs in serialized paths.
Take a rendernode as source and a GskPath and GskStroke,
and fill the area that is covered when stroking the path
with the given stroke parameters, like cairo_stroke() would.
This commit adds the basic infrastructure for paths.
The public APIs consists of GskPath, GskPathPoint and
GskPathBuilder.
GskPath is a data structure for paths that consists
of contours, which in turn might contain Bézier curves.
The Bezier data structure is inspired by Skia, with separate
arrays for points and operations. One advantage of this
arrangement is that start and end points are shared
between adjacent curves.
A GskPathPoint represents a point on a path, which can
be queried for various properties.
GskPathBuilder is an auxiliary builder object for paths.
Add GskMaskNode, and support it in the render node
parser, in the inspector and in GtkSnapshot.
The rendering is just fallback for now.
Based on old work by Timm Bäder.
A GskGLShader is an abstraction of a GLSL fragment shader that
can produce pixel values given inputs:
* N (currently max 4) textures
* Current arguments for the shader uniform
Uniform types are: float,(u)int,bool,vec234)
There is also a builder for the uniform arguments which are
passed around as immutable GBytes in the built form.
A GskGLShaderNode is a render node that renders a GskGLShader inside a
specified rectangular bounds. It renders its child nodes as textures
and passes those as texture arguments to the shader. You also pass it
a uniform arguments object.
Language bindings—especially ones based on introspection—cannot deal
with custom type hiearchies. Luckily for us, GType has a derivable type
with low overhead: GTypeInstance.
By turning GskRenderNode into a GTypeInstance, and creating derived
types for each class of node, we can provide an introspectable API to
our non-C API consumers, with no functional change to the C API itself.
We use a compilation symbol in our build to allow the inclusion of
specific headers while building GTK, to avoid the need to include only
the global header.
Each namespace has its own compilation symbol because we used to have
different libraries, and strict symbol visibility between libraries;
now that we have a single library, and we can use private symbols across
namespaces while building GTK, we should have a single compilation
symbol, and simplify the build rules.
gsk/gskenums.h:181: Error: Gsk: multiple "@GSK_TRANSFORM_CATEGORY_2D" parameters for identifier "GskTransformCategory":
* @GSK_TRANSFORM_CATEGORY_2D: The matrix is a 2D matrix. This is equivalent
^
gsk/gsktransform.c:1342: Warning: Gsk: gsk_transform_to_2d: unknown parameter 'm' in documentation comment, should be 'self'
gsk/gsktransform.c:1368: Warning: Gsk: gsk_transform_to_2d: invalid return annotation
gsk/gsktransform.c:1461: Warning: Gsk: gsk_transform_to_translate: unknown parameter 'm' in documentation comment, should be 'self'
They were a neat idea while they lasted. But now, it's time for
categorized transform nodes, where matrices with
GSK_MATRIX_CATEGORY_2D_TRANSLATE are the exact replacement.
Renderers have not been adapted for this purpose, so they (continue to)
run slow paths.
Adding the offset node broke serialization in 2 ways:
1. We store the enum value in the node, so make sure to not change it
for existing values
2. The offset node was missing in the deserialization lookup table
This is a special case of the transform node that does a 2D translation.
The implementation in the Vulkan and GL renderers is crude and just does
the same as the transform node.
Nothing uses that node yet.
This node essentially implements the feColorMatrix SVG filter. I got the
idea yesterday after looking at the opacity implementation.
It can be used for opacity (not sure if we want to) and to implement a
bunch of the CSS filters.
... and make the icon rendering code use it.
This requires moving even more shadow renering code into GSK, but so be
it. At least the "shadows not implemented" warning is now gone!
The node draws a solid CSS border, which can be used to cover everything
but dashed and dotted borders (double, groove, inset, ...).
For different border styles, we overlay multiple nodes and set their
colors to transparent for sides with non-matching styles.
