OpenGL support for other platforms

[SamoZ256]

At its current state, libwsi only support EGL for OpenGL context creation. The functions and files all feature EGL in its name, which makes it pretty much impossible to add another context creation API right now. Are there any future plans to change this?

[markbolhuis]

Yes and no. I have two (maybe 3) options for OpenGL support.

1. Wrap EGL. WGL and CGL in my own API and provide a cross platform way to create contexts and such.
   This is the most obvious thing for first class OpenGL support for this library, but Is a lot of work.

2. Do the bare minimum and just provide a means to get native platform handles from WsiPlatform and WsiWindow
   This is what I'm doing right now with EGL, but for CGL and WGL I'd need to add an equivalent wgl.h and cgl.h to include/wsi and then users can use that.

3. Wrap WGL and CGL in EGL. This is ambitions but technically possible. It's actually similar to what Microsoft already did in Mesa.
   EGL is a Khronos API and is designed to be cross platform. Its used on LInux. BSDs, Android, and Windows when using ANGLE . It should really be the preferred method, but It was developed too late to become the de-facto standard on mac and windows.
   The would be a lot of work as well and I don't have the time for it.

Right now I've picked 2 because it was easy to do. I don't have a computer with macOS or Windows on it to test any cross platform API.

[SamoZ256]

I would go with the first option. MacOS uses something called NSOpenGL for context creation and it's pretty easy to integrate.

[SamoZ256]

After looking at the eglgears example once again, it seems that EGL and NSOpenGL have a lot in common, and creating a small translation layer shouldn't be that hard. At least to provide the basic functionality.

[SamoZ256]

I have done a bit of research and I have created a small translation layer to translate EGL to NSOpenGL https://github.com/SamoZ256/NSEGL. Might be useful in the future.