Sega Saturn draws polygons as quad.Thanks for this method, VDP1 can draw distorted image correctly. Modern GPUs draw polygons as triangles. They can't draw distorted quad image correctly.
To avoid this failure, Generally perspective correction method is used. Since Perspective correction uses z value in 3D space and VDP1 does not have z vale, VDP1 emulator needs to calculate z value. This method works fine, polygons are draw as if they are in 3D space. like this.
But in some games These...
These days, I'm trying to solve performance regression problems. I implement my own performance counter and on screen graph. And I use Tegra Graphics Debugger and Tegra System Debugger. Finally Street Fighter Zero 3 back to 60fps.
It's very important showing what's going on inside.
I'm renting ASUS ZenFone2 for a month. a few fixes make uoYabause running on this device. But I found performance issue I may solve. I'll finish it, then release.