Neuro@neutanent
We just invented a new Global Illumination method.
IRIS: Indirect Radiance in Sparse Tiles for Low-Cost Diffuse Global Illumination
IRIS was invented by the $NEURAL team, and is - in scientific terms - essentially a real-time diffuse global illumination method built on a sparse, hashed world-space irradiance cache.
It trades unbiased accuracy for low, predictable cost and temporal stability, approximating multi-bounce light transport through stabilized previous-frame feedback rather than per-pixel path tracing.
In other words; A low-cost method for realistic bounced lighting in real-time graphics, built on a reusable lighting cache rather than per-pixel calculation.
But why does it matter?
In one sentence:
IRIS brings nice, natural-looking lighting to games and apps on hardware this was previously impossible, without the slowdowns or glitches that usually come with doing it cheaply.
The 3 key improvements are;
It makes good lighting cheap. Realistic bounced light - the way a red wall casts a soft red glow on a white floor - is normally very expensive to compute. IRIS gets a convincing version of it for a fraction of the cost, so it can run on phones, laptops, web games, and other modest hardware that usually can't afford it.
It's steady and predictable. It doesn't hiccup or cause sudden frame-rate drops. The cost stays roughly the same from frame to frame, which makes it easy to rely on. And it doesn't flicker or leak light through walls - common problems with cheap lighting tricks.
It saves the work instead of redoing it. Rather than recalculating the lighting for every pixel every frame, it stores it and reuses it. That's the main reason it's so much faster.
Below you can see we got a test scene going to find and resolve any remaining issues with IRIS.
But it's looking very nice already.