Moving the view area using e.g. a trackpad should be butter smooth.
Sadly, it currently isn’t. My perception is, it is ~12 fps on my Ryzen 3700X moving the view area in full screen at 4K resolution, maximum ~30 fps. This is just an out of time experience. Every web browser can move pictures more smoothly in its view area than Gwenview. This needs to be hardware accelerated on the GPU.
I will skip the system details because I know this is caused by purely CPU processing.