When extracting headless.Window's content via screenshots,
it can be useful to keep reusing the same image for output,
as well as specify which area of the Window is to be
extracted.
The updated Screenshot method does this by using the supplied
image.
API change: users must pass an existing image to Window.Screenshot.
Signed-off-by: Pierre Curto <pierre.curto@gmail.com>
GPU contexts can hold on to a significant amount of resources. Clean
them up immediately instead of at test cleanup.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
The clear background is the most useful, and the old behaviour can
be achieved by filling the entire viewport with a white paint.ColorOp.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
The new compute renderer can draw simple strokes. Test that clipping
works with a stroke basis, and that images can be drawn into strokes.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
Andy Balholm