OpenGL extension DispatchComputeGroupSizeARB supported?

Ailurus

Hi, I'm trying to use the OpenGL function DispatchComputeGroupSizeARB (see e.g. https://www.khronos.org/registry/OpenGL/extensions/ARB/ARB_compute_variable_group_size.txt). As it's not a OpenGL Core function, I assumed it would be in QtOpenGLExtensions. However, I can't find it here, which makes me wonder whether it is currently supported at all?

Kent-Dorfman

well it probably isn't support for your hardware/os combination then. if you are using linux then glxinfo will display the extensions that are supported.

Ailurus

Thanks for the suggestion, but it definitely is supported on my machine (the extension itself is called GL_ARB_compute_variable_group_size). Just wondering how to make it work within a Qt context (on Linux).

SGaist

Hi,

I think you are looking for the The QtOpenGLExtensions Library.

Ailurus

Hi, that is clear (I referred to it in my first post). The issue is that I cannot find the function glDispatchComputeGroupSize anywhere (neither through QOpenGLExtension nor in QOpenGLExtraFunctions). My QOpenGLContext confirms that the extension is supported. What am I overlooking? Using Qt 5.12 on Linux.

SGaist

Sorry I misread your original point and didn't saw you were already testing QOpenGLExtension.

I have found glDispatchComputeGroupSizeARB in Qt 5.13

What version of Qt are you using ?

Ailurus

I'm using 5.12, but with the official release of 5.13 in ~2 weeks I expect to be switching soon. How do you invoke/call glDispatchComputeGroupSizeARB in 5.13? Thanks!

SGaist

Sorry, I just realise I wasn't precise enough. I found the function declaration in the qopenglext.h header file but I haven't used it yet.

Ailurus

I checked, and it's also there in Qt 5.12 (in /usr/include/qt/QtGui/qopenglext.h), though even after including this header explicitly, the command is still undeclared. Perhaps @agocs knows how to proceed?

SGaist

You can also bring the question to the interest mailing list. You'll find there Qt OpenGL developers/maintainers. This is more a user forum.