QOpenGLFunctions 和 PySide2

Question

How to use QOpenGLFunctions from PySide2 ?

The problem is with the GLEnum , which the API documentation mentions but doesn't tell from where one could take it.

For example, I would like to call glGetString(), I try:

from OpenGL import GL
from PySide2.QtGui import QOpenGLFunctions as GLF

GLF.glGetString(GL.GL_VERSION))

But it produces an error.

TypeError: descriptor 'glGetString' requires a 'PySide2.QtGui.QOpenGLFunctions' object but received a 'IntConstant'

Answer 1

You have to use a QOpenGLFunctions associated with a current QOpenGLContext, for example you can use the following code:

from OpenGL import GL
from PySide2 import QtGui


if __name__ == "__main__":
    app = QtGui.QGuiApplication()
    off_screen = QtGui.QOffscreenSurface()
    off_screen.create()
    if off_screen.isValid():
        context = QtGui.QOpenGLContext()
        if context.create():
            context.makeCurrent(off_screen)
            f = QtGui.QOpenGLFunctions(context)
            print(f.glGetString(GL.GL_VERSION))

Output:

3.0 Mesa 20.1.6