tree baf5e9eaf66eb288b3c4959160fd87d3f4fda0c1
parent 0cae2de268ce3bd0c3714d0d27ef9afa42692f99
author Dmitri Shuralyov <dmitshur@golang.org> 1554700177 -0400
committer Nigel Tao <nigeltao@golang.org> 1568865429 +0000

shiny/driver/mtldriver: add start of a Metal API-based driver

The OpenGL API has been deprecated on macOS as of version 10.14.¹
The replacement for OpenGL on macOS is the Metal API.² This change adds
the start of a Metal API-based shiny driver. It can be activated by
specifying the -tags=metal build tag on macOS 10.13+. For example:

	go run -tags='example metal' golang.org/x/exp/shiny/example/icongallery

The goal of this CL has been to create an MVP. As a result, the focus is
on simplicity and correctness. Performance optimizations can come later.

The Metal API is currently used only to present the final pixels to
the screen. All rendering is performed on the CPU via the image/draw
algorithms (see https://blog.golang.org/go-imagedraw-package).
Future work is to use mtl.Buffer, mtl.Texture, etc., to do more of
the rendering work on the GPU.

From what I've observed so far, the Metal API is looking to be a great
fit for implementing the screen.Screen interface. But we'll learn more
when it's used to a greater extent of its full performance potential.

GLFW v3.2.1 is used for window creation, receiving input events, etc.
Package dmitri.shuralyov.com/gpu/mtl is used for Metal API access.
Helper packages for Apple's Core Animation and AppKit APIs are copied.

References:

¹ https://developer.apple.com/documentation/macos_release_notes/macos_mojave_10_14_release_notes?language=objc#3035786
² https://developer.apple.com/metal/

Change-Id: I0e02d660b776820ca499bfe7d67e47a9866d530c
Reviewed-on: https://go-review.googlesource.com/c/exp/+/171025
Run-TryBot: Dmitri Shuralyov <dmitshur@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Nigel Tao <nigeltao@golang.org>