Yoyo,
not sure, maybe. I had noticed those polys before but just assumed it was one part of the model poking through the other. Not sure they are transparent.
Ian! I don't quite understand why depth values would be incorrect for an ordinary quad that is comprised of two coplanar triangles. Why aren't they mathematically equivalent?
They are mathematically equivalent for co-planar quads. But the quads on the car aren't co-planar, they are bent :p
You can see the issue here. With the first split the quad is bent downwards. With the 2nd it's bent upwards.
The proper quad emulation it's like a mix between the 2, which gives us very different depth values.
The depth issue is a lot easier to solve with tessellation. But the texturing of quads is much harder. When experimenting I increased the poly count by a factor of 10, then finally the lines on the car were the shape they were meant to be. But at 10x the polys it started to choke the renderer. But increasing the resolution brought the same problems back again. So yeah I guess this would make porting scud pretty hard without really going back and re-texturing/remodeling the cars.
This is scud race on demul. I guess this was some prototype/demo version for the dreamcast, I don't know if it was ever released?
You can see the same bug there
I've honestly never seen any other renderer attempt to actually properly emulate quads, I don't know if this thing is a first or what.
But not quite sure what to do with the code. I'm not even sure Harry can run it on his pc.. and that's not good at all, since he has been such a major contributor to the project. I think the best idea might be to simply have 2 sets of shaders that can be switched between versions. The shader inputs are identical. That might be one way of doing it.
by Ian » Mon Oct 16, 2017 12:38 pm 
