Compatibility between OpenGL ES 3.0 and Desktop

OpenGL
1

I am attempting to update a game engine I made from OpenGL ES 2.0 to 3.0. I believe I have completed this process and it seems to work great on mobile, but when working internally, we had normally used OpenGL Desktop on Mac (gl.version: 4.1 Metal - 88.1)

It seems to be getting hung up on this line:

        glVertexAttribPointer(offset, TEXTURE_COMPONENT_COUNT, GL_FLOAT, GL_FALSE, TOTAL_SIZE, data);
        CM_GL_CHECKERROR();
        glEnableVertexAttribArray(offset);

From my reading, it seems like the Desktop version is now expecting you to create a base Vertex Array Object whereas ES has it automatically.

However, when I attempt to do this, it does not work (and also breaks the ES version)

    glGenVertexArrays(1, &VertexArrayObject);
    glBindVertexArray(VertexArrayObject);

I am doing this creation when I create the OpenGL manager object in my engine, so it is not occuriing every frame, but I am attempting to bind it every frame.

Of note, on Desktop, both the glVertexAttribPointer and glGenVertexArrays both give an OpenGL error code of 0x0502.

Any suggestions would be very much appreciated!

2

This is GL_INVALID_OPERATION (0x0502).

Ok, first. This is Apple Mac. They’ve stated their lack of support for OpenGL. So take whatever you observe on this platform with a pound of salt. Results on a desktop PC with an NVIDIA GPU+drivers might net you much more dependable results.

Second, are you absolutely certain that no GL error was posted “before” the GL calls that you think triggered one. Add a glGetError() before these calls to be sure. Part of why I suggest this is that, on Mac, sometimes the context init is actually what throws the GL error. For instance:

Also, found 2 reports on gpuinfo.org with similar GL_VERSION reports to yours (both with GL_RENDERER = Apple M1 Max):

Seems a bit odd that these 2 OpenGL 4.1 Core driver reports don’t support ARB_vertex_array_object, when I believe VAOs were accepted into core in OpenGL 3.0.

If I were you, I’d try your desktop testing on something other than a Mac. For instance, a PC with an NVIDIA GPU+driver.

3

Thank you for the suggestions. I had already put error checking everywhere to narrow down the exact line

    CM_GL_CHECKERROR();
    setFullScreenViewport();
    CM_GL_CHECKERROR();
    glGenVertexArrays(1, &VertexArrayObject);
    CM_GL_CHECKERROR();
    glBindVertexArray(VertexArrayObject);
    CM_GL_CHECKERROR();

This Mac version is just for our artists and programmers to be able to do their development in the desktop, so unfortunately, I need to get it working on the poorly supported M series chips.

4

Does your CM_GL_CHECKERROR function call glGetError repeatedly until it returns GL_NO_ERROR? Or does it just call glGetError once? It should be the former; an implementation is allowed to store multiple errors.

GL_INVALID_OPERATION (0x0502) isn’t an allowed error for glGenVertexArrays; the only allowed error is GL_INVALID_VALUE if you request a negative number of arrays. So this error being reported for glGenVertexArrays is more likely to be an issue with the error reporting code (either yours or the implementation’s).