By returning the allocated data buffer, Ops can become an interface
in a future change without forcing operations to allocate.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
With public ImageOp fields there was no way to mark an image.Image as modified.
Replace them with NewImageOp that always make a copy, and use the opportunity
to ensure the copy is ready to upload to a GPU texture.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
Instead of adding an implicit ClipOp, return a ClipOp ready to use, freeing the
caller from recording a macro.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
Elias Naur