kons-9 is using opengl v4.6 on Linux and opengl v2.1 on macos which are fundamentally incompatible versions

[awolven]

[kaveh808]

I came across this:

https://stackoverflow.com/questions/65802625/develop-using-opengl-4-x-on-osx-big-sur

[JMC-design]

well it shouldn't be hard to limit to 4.1 until something like this is drop in replacement. https://github.com/openglonmetal/MGL

[awolven]

(glfw:with-init-window (:title "kons-9" :width (first window-size) :height (second window-size) :context-version-major 4 :context-version-minor 1 :opengl-forward-compat t :opengl-profile :opengl-core-profile)

...)

On Thu, Sep 8, 2022 at 11:17 AM Johannes Martinez Calzada < @.***> wrote:

well it shouldn't be hard to limit to 4.1 until something like this is drop in replacement. https://github.com/openglonmetal/MGL

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[kaveh808]

Is there a way of getting our existing OpenGL code working with 4.1 on MacOS? If not, what changes are necessary?

I tried the above snippet and got:

An unhandled error condition has been signalled:
   OpenGL signalled (1282 . INVALID-OPERATION) from MATRIX-MODE.

Found this link: https://stackoverflow.com/questions/48249518/opengl-error-1282-invalid-operation-when-using-glut-3-2-core-profile

Tried some other flags, including :opengl-profile :opengl-compat-profile but got:

An unhandled error condition has been signalled:
   NSGL: The targeted version of macOS only supports forward-compatible core profile contexts for OpenGL 3.2 and above

[kaveh808]

Looks like Apple does not support deprecated OpenGL past 3.2:

https://www.khronos.org/opengl/wiki/Legacy_OpenGL

So we will have to rewrite all our graphics code (which we were planning to anyway) to move to 4.1.

The question now is what is the best platform to target -- OpenGL 4.1, Vulkan, etc.

In the meantime, we'll keep MacOS at 2.1 and use different versions of Andrew's text engine for MacOS and Linux.

[ghost]

This might be an opportunity to abstract the rendering "backend". Should you spend your time chasing bugs in compatibility hacks or work up front on a flexible architecture that supports either OpenGL or Metal (etc.) directly? Remember you are interacting with a scene graph, which already is an important abstraction towards this approach. SGI's Open Inventor (while at times a little too "conjoined" with OpenGL and X windows) took such an approach.