MacOS support

[nicoabie]

• trying to add macos support using latest freeglut https://github.com/freeglut/freeglut/blob/07a3e80780c289b51bc723415ef41cef6b026aed
• tutorials 1 and 2 working in X11 and Cocoa
• removes old freeglut that didn't support macos
• tries to stop using glload library

would like feedback if possible if this continues to be running on linux or I broke something.

[paroj]

take a look at #161 where I assume you install freeglut with brew.

It allows successfully compiling the tutorials, however it requires X11 to run..

[nicoabie]

Hey thanks a lot for taking the time for doing that!
Probably you saw me struggling with the linux builds and yes I'm was not very sure of what I was doing.

I tested #161 doing a brew install freeglut.

The first issue I found is ERROR: Internal error <FBConfig with necessary capabilities not found> in function fgOpenWindow and that is because X11 does not like GLUT_STENCIL see

gltut/framework/framework.cpp

Line 132 in 2c81b64

#if defined(__APPLE__) && !defined(USE_COCOA)

After removing GLUT_STENCIL and running again Tut01 I get a segmentation fault.

I run cmake -DOPENGL_gl_LIBRARY=/opt/homebrew/lib/libGL.dylib .. then cmake --build . --config Release

Same segmentation fault

I comment out glutInitContextVersion (3, 3); because in my branch I saw macos didn't like that and then I get

Your OpenGL version is 0, 0. You must have at least OpenGL 3.3 to run this tutorial.

Commenting that glload code out another seg fault whereas in my branch it picked up the mesa implementation.

What I was going to attempt before looking into this PR was remove glload in favor of glad https://www.khronos.org/opengl/wiki/OpenGL_Loading_Library also it seems possible to use include(FetchContent) in cmake to not have the libs code in the repository and have a better tracking of deps versions.

I'm new to all this so I could be wrong but trying to give a hand so let me know your thoughts and how can I be of help.

[paroj]

it seems that freeglut does not work with recent OSX because of X11.

As SDL2 is a better choice for starting a OpenGL project anyway, I would rather port the framework to that instead of trying to fix freeglut.

[nicoabie]

In my PR I'm able to run lastest commit of freeglut (not latest release) both with X11 and Cocoa