[MUD-Dev2] [DESIGN] Ray traced environments

[Mike Rozak]

John Buehler wrote:
> Processors are fast.  They're getting more numerous per box.  We have
> graphics coprocessors.  Physics coprocessors are also out there.  It may 
> be
> time to start talking about raytracing in games.
... snip


I have been saying this for awhile. Some random comments:

- As the rendering technology gets more complex (such as ray tracing or 
stochastic ray tracing), GPUs lose their cost-efficient design compared to 
CPUs... which means that GPUs will eventually disappear, and you'll be using 
12 cores from your 16 core processor to do rendering.

- Physics co-processors are still-born.

- Ray tracing doesn't give you that much over current scanline rendering, 
kind of. It provides slightly better shadows and curvy mirrors. It does, 
however, become very efficient when drawing LOTS of objects with LOTS of 
polygons, such as forests. My own ray tracer is slower than my scan line 
renderer, unless I tell them both to draw a forest with a million trees, in 
which case ray tracing starts showing promise. The reason is that 
ray-tracing is O(pixels), while scan-line tends to be O(polygons) + a small 
contribution from O(pixels).

- What does provide a huge improvement is stochastic ray tracing, which 
produces correct soft shadows, blurry reflections, diamonds, wine-glass 
effects, good motion blur, and secondary light bounces. It's 10x-1000x as 
slow as ray tracing though.

- The virtual world toolkit I'm working on can also do ray tracing, but it's 
not really worth the slowness. (It's only a few days coding from stochastic 
ray tracing, but there's not much point implimenting it now.)