Adding to the quality is Guerrilla's chosen anti-aliasing solution. Back in the February reveal, FXAA was utilised with the firm hinting at a more refined TMAA solution under development in Sony's Advanced Technology Group. TMAA is now TSSAA - temporal super-sampling anti-aliasing.
"It is still very similar to FXAA. It's not FXAA, it's a similar filter but much higher quality," explains Michal Valient.
"It's still screen-space - TSSAA - we've lost the sub-sampling of depth. We had that sub-sampling as well, reconstructing edges with that but it was costly and didn't really add that much so we removed that," adds van der Leeuw.
"We collect samples from the previous frames and try to blend that into the mix on a basis that is a derivative of FXAA. It's something that blends in a little bit of temporal math, trying to get something from previous frames."
"We're very careful in what we use from the previous frames. If it's a good frame, why throw it away? We basically gather as much of the pixels from the previous frames that you can apply to this one as well and re-project them," adds Valient. "We get more samples per pixels. Normally you'd need to apply super-sampling or multi-sampling to get a similar effect. We try to get the data from the previous frame."
Re-using existing data for other systems is an approach often used by developers - Guerrilla uses this not just for anti-aliasing, but for ambient occlusion too. But this isn't your standard screen-space approach:
"It's called directional occlusion. It's a by-product of our reflection system. We use the calculation for reflections to determine how much of a space is actually visible from a certain point and we re-use the same information for AO," explains Michal Valient. "AO, if you think about it, is the same as reflection but with a much wider lobe. You want to know about the entire hemisphere around any point, how much is visible, so you can re-use that information. I wouldn't say it's SSAO because there's way too many tricks in it to make it look good."
