PyQt6 does not allow to use the Qt.AA_UseDesktopOpenGL attribute

[8Observer8]

Hello,

This PySide6 example works:

import sys

from OpenGL import GL as gl
from PySide6.QtCore import Qt
from PySide6.QtOpenGLWidgets import QOpenGLWidget
from PySide6.QtWidgets import QApplication


class Widget(QOpenGLWidget):

    def __init__(self):
        super().__init__()
        self.setWindowTitle("PySide6, OpenGL 3.3")
        self.resize(400, 400)

    def initializeGL(self):
        gl.glClearColor(0.5, 0.5, 0.5, 1)
    
    def paintGL(self):
        gl.glClear(gl.GL_COLOR_BUFFER_BIT)

if __name__ == "__main__":
    QApplication.setAttribute(Qt.AA_UseDesktopOpenGL)
    app = QApplication(sys.argv)
    w = Widget()
    w.show()
    sys.exit(app.exec())

But when I translate this example to PyQt6 it does not work because it says that 'Qt' has no attribute 'AA_UseDesktopOpenGL':

import sys

from OpenGL import GL as gl
from PyQt6.QtCore import Qt
from PyQt6.QtOpenGLWidgets import QOpenGLWidget
from PyQt6.QtWidgets import QApplication


class Widget(QOpenGLWidget):

    def __init__(self):
        super().__init__()
        self.setWindowTitle("PyQt6, OpenGL 3.3")
        self.resize(400, 400)

    def initializeGL(self):
        gl.glClearColor(0.5, 0.5, 0.5, 1)
    
    def paintGL(self):
        gl.glClear(gl.GL_COLOR_BUFFER_BIT)

if __name__ == "__main__":
    QApplication.setAttribute(Qt.AA_UseDesktopOpenGL)
    app = QApplication(sys.argv)
    w = Widget()
    w.show()
    sys.exit(app.exec())

If I delete the QApplication.setAttribute(Qt.AA_UseDesktopOpenGL) line of code I see the message:

Traceback (most recent call last):
  File "main.py", line 47, in initializeGL
    gl.glClearColor(0.5, 0.5, 0.5, 1)
  File "E:\ProgramFiles\Python\Python38\lib\site-packages\OpenGL\platform\baseplatform.py", line 415, in __call__
    return self( *args, **named )
  File "E:\ProgramFiles\Python\Python38\lib\site-packages\OpenGL\error.py", line 230, in glCheckError
    raise self._errorClass(
OpenGL.error.GLError: GLError(
        err = 1282,
        description = b'invalid operation',
        baseOperation = glClearColor,
        cArguments = (0.5, 0.5, 0.5, 1)
)

[8Observer8]

musicamante gave the correct answer in the comments of this topic

PyQt6 has removed anything from Qt, it's a binding: they only changed the python access to enums, which now require the full enum scope: Qt.ApplicationAttribute.AA_UseDesktopOpenGL

import sys

from OpenGL import GL as gl
from PyQt6.QtCore import Qt
from PyQt6.QtOpenGLWidgets import QOpenGLWidget
from PyQt6.QtWidgets import QApplication


class Widget(QOpenGLWidget):

    def __init__(self):
        super().__init__()
        self.setWindowTitle("PyQt6, OpenGL 3.3")
        self.resize(400, 400)

    def initializeGL(self):
        gl.glClearColor(0.5, 0.5, 0.5, 1)
    
    def paintGL(self):
        gl.glClear(gl.GL_COLOR_BUFFER_BIT)

if __name__ == "__main__":
    QApplication.setAttribute(Qt.ApplicationAttribute.AA_UseDesktopOpenGL)
    app = QApplication(sys.argv)
    w = Widget()
    w.show()
    sys.exit(app.exec())

[SGaist]

Hi,

That's something you should bring to the PyQt author.

[8Observer8]

@SGaist I sent a link to this topic to this email address: pyqt@riverbankcomputing.com I found it here: https://www.riverbankcomputing.com/mailman/listinfo/pyqt

[8Observer8]

musicamante gave the correct answer in the comments of this topic

PyQt6 has removed anything from Qt, it's a binding: they only changed the python access to enums, which now require the full enum scope: Qt.ApplicationAttribute.AA_UseDesktopOpenGL

import sys

from OpenGL import GL as gl
from PyQt6.QtCore import Qt
from PyQt6.QtOpenGLWidgets import QOpenGLWidget
from PyQt6.QtWidgets import QApplication


class Widget(QOpenGLWidget):

    def __init__(self):
        super().__init__()
        self.setWindowTitle("PyQt6, OpenGL 3.3")
        self.resize(400, 400)

    def initializeGL(self):
        gl.glClearColor(0.5, 0.5, 0.5, 1)
    
    def paintGL(self):
        gl.glClear(gl.GL_COLOR_BUFFER_BIT)

if __name__ == "__main__":
    QApplication.setAttribute(Qt.ApplicationAttribute.AA_UseDesktopOpenGL)
    app = QApplication(sys.argv)
    w = Widget()
    w.show()
    sys.exit(app.exec())

[8Observer8]

A few basic changes in PyQt6 regarding shader-based OpenGL graphics