Outline represents a clipping operations that clips all drawing outside
a closed path. Before this change, paths not closed we're patched up by
adding an implicit line from the endpoint to the beginning.
These fixups are inefficient for a rare case, but acceptable because the
old renderer post-processes all paths anyway. However, the new compute
renderer don't need post-processing in most cases, making fixups too
expensive.
Given that clipping to an open path is fundamentally undefined and that
implicit fixup with a closing line segment is merely a way to force the
clip to be well-defined, this change adds a panic to Outline for Paths
that are not closed.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
The CPU fallback of the compute renderer needs ReadPixels data in OpenGL
format (origin at bottom left). Unfortunately, the OpenGL driver
automatically mirrors images in the Y-axis to match the top left origin
image.RGBA.
Remove the mirroring from the driver and introduce a DownloadImage to
restore the old behaviour.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
It is no longer necessary for outside users of package gpu to explicitly
initialize a specific driver. The Direct3D driver is already internal,
this moves the OpenGL driver internally as well. The rename to opengl is
to avoid the name clash with the low-level "gioui.org/internal/glimpl"
package that we're about to rename.
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>
The convert program is only used by the shaders from package gpu, and
we're about to make the backend package imported by the program internal
to package gpu. Move the converter below package gpu.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
The package app/internal/d3d11 now contains only the GPU backend on
Direct3D. Move it below package gpu to reflect that.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
Elias Naur