According to
https://developer.apple.com/library/archive/documentation/Cocoa/Conceptual/Multithreading/CreatingThreads/CreatingThreads.html#//apple_ref/doc/uid/20000738-125024
Cocoa is by default not multithread-safe for programs that use the posix
api for creating threads:
"
For multithreaded applications, Cocoa frameworks use locks and other
forms of internal synchronization to ensure they behave correctly. To
prevent these locks from degrading performance in the single-threaded
case, however, Cocoa does not create them until the application spawns
its first new thread using the NSThread class. If you spawn threads
using only POSIX thread routines, Cocoa does not receive the
notifications it needs to know that your application is now
multithreaded. When that happens, operations involving the Cocoa
frameworks may destabilize or crash your application.
"
That includes Go programs.
The fix, as discovered by Steeve Morin, is to create and launch
an empty NSThread.
Add a package that does that, and use it everywhere Cocoa is used.
Sigh.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
The new Framebuffer.ReadPixels method is enough to implement
Window.Screenshot. Use that instead of the OpenGL-specific
implementation.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
To prepare package headless for multiple backends, refactor the common headless
driver to no longer assume an OpenGL context. Instead, introduce a headless
backend type and the OpenGL implementation, glBackend.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
This is a refactoring change to prepare for another gpu.Backend
implementations.
Notably, app/loop.go no longer imports gpu/gl.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
The rendering implementation is needed for using Gio UI with external
window libraries such as GLFW. Expose it in the new package gpu.
Updates #26
Signed-off-by: Elias Naur <mail@eliasnaur.com>
We'd like to support Gio using a different renderer binding than
the builtin. A first step is to define the Functions interface
in package gl, and extract the concrete implementations to a
separate package.
Updates #26
Signed-off-by: Elias Naur <mail@eliasnaur.com>
The macOS backend uses a desktop OpenGL context, not a OpenGL ES
context. The main difference is that sRGB have to be enabled and
a vertex buffer must be bound.
Do that and fix Window.Screenshot for scenes more complex than a
glClear.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
Elias Naur