We're about to encode clip.Paths with the format compatible with the
compute renderer. This change extracts the encoding to a re-usable
package.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
All functions left in the old package unsafe were provided byte slice
views of other types. Rename the package accordingly and avoid a name
clash with the standard library package unsafe.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
This change tracks materials so that only the updated materials needs to
be rendered.
Materials are likely cheap to render each frame, at least compared to
the rest of the compute pipeline. However, the CPU fallback must
transfer all changed materials to CPU memory, and a cache is a great
improvement over fetching all materials every frame.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
We're about to cache the transformed materials. It's easier to do when
quads can be constructed before determining their atlas position.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
There are no longer any importers of package backend outside of
gioui.org/gpu. Move it internally, and rename it to the slightly more
specific "driver" while we're at it.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
Return the output framebuffer from BeginFrame, to make it clear that
it may change between frames. Delete CurrentFramebuffer which is no
longer needed.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
We're about to change the last stage of the compute pipeline to only
accept images, not sampled textures. This change prepares materials
for pixel-aligned image copying by pre-rendering images to a texture,
applying transforms.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
Gio UI may be overlaid on top of custom graphics such as in the glfw example.
That will only work if Gio doesn't clear the screen (to white).
Signed-off-by: Elias Naur <mail@eliasnaur.com>
The old renderer is still the default, so the new compute renderer will only be
used in the rare case the old renderer is not supported but the new is. That
happens on the Samsung J2 Prime and Moto C Android phones. Or set the
GIORENDERER environment variable to "forcecompute" to disable the old renderer:
$ GIORENDERER=forcecompute go run ...
Missing features:
- Gradients are not supported yet, and render as a solid color.
- Draw timers are not added, and profile.Events are not emitted.
- Stroked paths may in some cases appear corrupted because their clip
outlines are not continuous when generated by Gio. Sebastien is
working on a fix.
- The new renderer shares most CPU-side logic with the old renderer,
resulting in several inefficient conversion steps between the old
operations representation and the new. This is slower, but minimizes
divergence in features and bugs between the two renderers.
Roadmap:
- The compute renderer supports features that Gio does not yet
exploit: stroked paths with round caps, transformations, lines,
cubic beziér curves.
- More stroke styles and maybe dashed strokes natively in shaders.
- Metal and Direct3D ports.
The most important feature is porting the renderer to run on the CPU. A
CPU renderer will both support Gio on devices with insufficient GPU
support, and allow us to remove the old renderer. Two renderers is twice
the maintenance but the feature set of the weakest implementation.
Signed-off-by: Elias Naur <mail@eliasnaur.com>