This devlog has originally been published on Discord and has been crossposted here to fill the category a bit.

A note before I get into it, I also updated the free iMMERSE shaders on Github. Since they share modules, I can only ensure compatibility between iMMERSE Pro and iMMERSE for the current newest public version. It’s therefore best to update them as well, if you keep them in the same folder.

iMMERSE Pro RTGI

• I’ve come up with a new ray intersection system that is far more accurate than the previous ones. You can get the same results with 25-30 steps as you’d get with 200 before, I’m not kidding. If you are one of the maniacs who use 200 steps for best quality, the limit of 40 in the GUI will suffice now. Trust me. 10 steps is about on par with 40 before. Performance per step is a tiny bit lower ofc but with settings that are visually equal, it’s much faster now.
• IBL has received a major upgrade. I went away from the single probe system and went for a full on irradiance probe grid using spherical harmonics. They are FAR more accurate and are able to almost maintain the scene lighting without any tracing. In the picture after this post you’ll see what I mean.
• Smooth Normals MK2! Scroll to Launchpad news for more.
• Fixed the stripy problems on DX9 for good and it should be faster on DX9 as well

iMMERSE Pro Regrade + Solaris

• ported these two effects to the new standard
• removed the native color processing again because it only caused headaches (thank DX9 :P) and it didn’t do much anyways, I mostly used that as internal testing
• LUTs are built via Compute Shaders now on DX11, OpenGL and Vulkan. This yields a performance increase of about 20% and a VRAM usage reduction of – no joke – 90%. It’s only using 2MB VRAM now instead of 22MB.
• added a colormap display where you can analyze how each ReGrade module changes your colors
• fixed a bug with the color remapping that became evident when you used extreme settings (like remapping red to green or such)
• Solaris now uses something called cone overlap internally, produces slightly more natural colors
• fixed bug with the full res input mode that drastically changed intensities

iMMERSE Launchpad

• Smooth Normals MK2! They’re faster than before and a LOT more accurate. I’ve invented a totally new algorithm for that which splits surfaces into convex and concave and finds common focal points…. it’s complicated. If you want to learn more, let me know. They are however integrated in Launchpad (which you need anyways) so toggle them in there. They can also be toggled at runtime.
• Greatly improved normals generation even without smooth normals. Will handle small geometry much better now, for sharper results
• Greatly enhanced the feature detection for optical flow using something called circular harmonics. It’s a type of fourier series defined on the circle and allow for encoding the properties of a local patch of color into a few numbers. This makes it much more robust against repeating patterns. See preprocessor documentation how to enable this.

iMMERSE MXAO

• added a preprocessor define to enable the use of Launchpad’s (smooth) normals. This is disabled by default because MXAO’s normals generation is really fast and AO is usually used for lower end systems where RTGI is overkill. Launchpad incurs a relatively high base cost because of the motion vectors so I decided to make this optional if you only want to use MXAO.
• fixed the long standing problem with stripy results on DX9. It should be as fast and accurate on DX9 now. Also, the filter derped out on DX9, not anymore.