Enabling hardware acceleration in QT 6 builds makes images not render (win 10, 64 bit)

[dogboydog]

Describe the bug
There's a rendering issue for me and eishiya under recent QT 6 windows builds. With hardware acceleration turned on many types of images don't seem to render in the map editor. Interestingly, the tileset editor does render the tiles.

To Reproduce
Steps to reproduce the behavior:

1. Open a map under windows 10
2. Ensure hardware acceleration is turned on
3. Observe tiles and image collection objects not rendering
4. Turn off hardware acceleration
5. Observe the images now starting to render

Expected behavior
The images should render.

Media
Map editor

Tileset editor

Have not tested on any other OS yet.

Specifications:

• OS: Windows 10
• Tiled Version: confirmed in latest master and also the Feb 15 "version less than" scripting utility commit has the issue

[eishiya]

I was initially able to reproduce this, but after restarting Tiled, everything is working fine. Very weird bug(?).

[dogboydog]

For me the issue persists after installing graphics drivers updates, rebooting, and trying to restart Tiled a few times. Also reproduced on a second Windows machine

[dogboydog]

Reproduced on a Debian Linux VM as well.

[bjorn]

Interestingly, the tileset editor does render the tiles.

Well, the tileset editor never uses hardware rendering. That option is limited to the map editor. :-)

Apart from being new in Qt 6, the issue appears to have something to do with the use of QPainter::drawPixmapFragments. When I disable that the rendering is fixed. So potentially something broke in case of multiple calls to this function.

[bjorn]

Hmm, this still worked fine in Qt 6.3.2, so it's a regression somewhere in Qt 6.4. :-(

[bjorn]

Reported as QTBUG-111416.

[dogboydog]

Thanks, it's fixed for me in the newest build