SEUS PTGI E11 Dev News (Patreon)

Hello again! Here's what's going on with the development of SEUS PTGI E11!A lot of research has gone into this update, and there are still some things being worked out that will hopefully arrive in E12. The adaptive temporal GI filter (for instant lighting changes) is still being worked on, for example, and won't make it into E11.

I've put a lot of time into working on optimization. Most ideas don't work out, but some do. I've managed to optimize the GI filter a bit without redesigning it, so it should mostly look the same. The reflection filter has a new optimization feature that basically tries to skip doing denoising if reflections aren't very visible in a region of pixels. It works fairly well, and it does cause additional noise in areas where reflections are subtle/not very bright, but I'll include an option to disable this optimization.

The worst performance situations occur when using high resolution resource packs with normal and specular maps and Full Raytrace Reflections is On. I've tried to save some frames in this situation by simplifying the shading of blocks that rays hit. This makes almost no difference visually in most cases, but gives a bit performance boost. The only problem left with it is that this simplification is really noticeable with reflected blocks that are close to the reflective surface. I need to add logic to fix this to be able to say just how much performance improvement there will be, but things are looking good!

Quite a bit of research has gone into improving mod support in the future as well. I'll probably be putting together a tool that will help users setup SEUS PTGI to be compatible with the mods they've got installed. This will require a rework of SEUS PTGI's block ID handling and voxelization to make sure things don't break too much with unexpected block shapes. Know that this is something I'll be working on, even if I don't mention it in the next dev news post.

Lastly, I've put a lot of work into one of the visually weakest areas of PTGI, the sky and clouds. The sky is a really simple (and really fake) model I put together to be as lightweight as possible. But recently, I've found a new approach that relies more heavily on the math (so a lot of work goes into creating the right formulas), but after the math is worked out, the shader code is as simple as evaluating the final formula, without any iteration loops. The result is a hopefully more realistic sky overall, but it still needs a little bit of work. Expect somewhat abrupt dawn/dusk transitions while that is being worked out.

And well, the clouds in SEUS PTGI are ancient and bad. When approaching writing the new clouds, I knew that I wanted them to be cheap enough to have them render in raytraced reflections and GI. So, volumetric clouds were out of the question. I decided to see how far I could push a 2D clouds system to look 3D.

Also, I experimented with making the structure of the clouds more blocky, to bring some Minecraft essence to them.

Which look do you prefer? I'll have an option for both, but I've always enjoyed the juxtaposition of a blocky world rendered in a realistic manner, and the blocky clouds give that sort of vibe.

Once again, I'll provide an option to disable them altogether if you'd rather save the frames, but the performance impact is looking pretty low so far, since they're just 2D clouds (no raymarching). 

Looking forward to hearing your thoughts!