i have a pimax 8kx, and when i set my pitool to render quality 2.0 (FOV large), i got a really good looking image for my opinion in iracing. I’m using openxr with PimaxXR + the opnenxr toolkit.
I have no idea (can’t see it anywhere !?) what the original resolution with render quality 2.0 is, but with the openxr toolkit i have the opportunity to “override resolution” and can set a resolution i like to have then.
I find when i set it to around 5400x… i get a smooth gameplay and stable fps.
My question is, is there a resolution that would exactly match the right proportion? As i know so far there should be a “sweetspot resolution proportion” that if you match it the image should look better/sharper, than when you are not “matching” it … so as for example 5417x… instead of 5430x…
Short answer no. Believe it or not, setting pitool to 1.0 render, steam vr ro 100% and game to 100% is considered to be optimal, (exlcuding dlss and fsr). For parallell projections off that resolution in large fov is 5xxx x 3160. That resolution only means you should be getting at least the ppd of your display being rendered at the focal point with a standard eye releif and IPD. So technically speaking that resolution is the sweetest spot. But forget about that for a moment: The real trick is to aim for the a stable fps above that of your HMD refresh rate (or half if you can keep it above 1/2 for smart smoothing and dont mind the artifacts). Then crank that resolution until you occasionally get frame rates just below that of your hmd, then dial it back a bit to get that buttery smooth 75 or 90 or 120hz match.
To put it succinctly, there is a soft native resolution, but no match as the real exact native resolution is never exactly acheived across the entire display due to the transform of 2d to VR via barrel/pincushion distortion/correction.
So opposite of 2d you should dial your frame rate first, then hope to acheive the highest resolution possible without sacrificing smooth frame pacing - then hope for a good resolution. If youre desperately trying to acheive higher resolution then you can employ Smart smoothing or at least compulsive smoothing.
Contrary to our perception our current rendering actually RENDERS at a HIGHER PPD outside the focal point. Just look at a piece of graph paper held flat about 6 inches from your eye. You’ll note that per degree there are more squares outside your focal point. This is the opposite of the desired rendering and is why FFR and more precisely DFR are wonderful options!