This is now tracking the clips added by the clip nodes.
If any particular node can't deal with a clip, it falls back to Cairo
rendering. But if it can, it will render it directly.
... and implement it for the Cairo renderer.
It's an API that instructs a renderer to render to a texture.
So far this is mostly meant to be used for testing, but I could imagine
it being useful for rendering DND icons.
That code doesn't do anything.
And what the code should be doing (clearing the abckground) isn't
necessary as cairo drawing is guaranteed to clear the surface.
This does a conversion to/from GBytes and is intended for writing tests.
It's really crude but it works.
And that probably means Alex will (ab)use it for broadway.
I had originally thought I'd use GskShadow for box-shadow, but didn't in
the end.
So now it's only used for text-shadow and icon-shadow, and those don't
have a spread.
Instead of a separate allocation for any arrays in the render node
we allocate these as part of the render node itself, using C99
flexible arrays.
This leads to less allocations, which is nice, but the major reason
for this is that it allows us to change the allocation scheme further
in the future. For instance, we want to do stack-like allocation so
that all the render-nodes for an entire frame are allocated in one
(or a few) chunks.
Instead of constantly recalculating this (especially recursively for
parents!) we do it only on construction, because everything is
immutable anyway. Also, most nodes had a bounds already and can
use the new parent member instead.
We also do direct access to the node bounds rather than calling
gsk_render_node_get_bounds in various places, which means
we do less copying.
... 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.
This way we can pass the command pool around.
And that allows us to allocate and submitcustom buffers.
And that is necessary to make staging images work.
