The OpenGL (ES) implementations on Apple platforms are deprecated and
don't support GPU compute programs. This change adds support for the
replacement, the Metal GPU API.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
The only reason for separate files is Objective-C callbacks into Go,
or when the Go side is common, yet the Objective-C side differs from
macOS to iOS.
Signed-off-by: Elias Naur <mail@eliasnaur.com>