@feeef It could very well be a problem in the tablet driver, or the QT framework, so i did some research and found a neat application to test my suspicion. It checks for the tablet input and outputs its coordinates like P2D, checking if you’re using a mouse or tablet, and draws on the canvas, but also some other things for easier debugging. The thing is though that i experience no lagging behind in this. There could be many reasons for that though, and i didn’t look too deep into the code, but i thought it would be interesting to share it nonetheless.
I tried roughly to compare how it’s doing drawing and checking compared to how P2D does it, but i’m simply not experienced enough in C++ to get something out of it.
My point with this is, that it might be something fixable when it’s not doing it in another application written in the same framework. Maybe it’s optimization but i don’t think it is. While the strokes are being produced, the cpu is not working at all.