A few GTK4 widgets, 3d transformations and css...
For some reason video uploading doesn't work right now, so see https://twitter.com/alexm_gnome/status/1379481819133972482 for a video.
@robby that would be a problem - widgets can't be arbitrary polygons and GSK can't draw those anyway. You can have rectangles, so will have to stop on Wolfenstein 3D.
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