[Radiance-general] Hardware accelerated radiance

[Greg Ward]

Hi Mike,

Unless you're really, really careful, the communication with the FPGA  
will kill any savings you make in the ray tracing times on a hardware  
implementation.  This has been found time and again for the past  
decades by the numerous people who have written or attempted  
ray-tracing on hardware.  The literature is extensive in this area, and  
I suggest you start with one of the textbooks on parallel rendering  
algorithms, such as:

Practical Parallel Rendering
by  Alan Chalmers (Editor), Timothy Davis (Editor), Erik Reinhard

http://www.amazon.com/exec/obidos/tg/detail/-/1568811799/ 
qid=1109613036/sr=1-1/ref=sr_1_1/104-1366464-7333544?v=glance&s=books

Regarding oconv, you might have better luck converting some larger  
models into a Radiance mesh, which uses less memory to represent  
triangular tesselations.  Most CAD software these days spits out  
hundreds of thousands of polygons, even when they aren't needed, such  
as for large, flat surfaces.  Using Alias/Wavefront .OBJ as your export  
format, obj2mesh can convert these models much more efficiently into  
Radiance.

-Greg

> From: Michael Kruger <mike at cityscape3d.com>
> Date: February 28, 2005 3:24:07 AM PST
>
> Has anyone done any work on integrating radiance with a hardware  
> solution? I'm thinking of porting the basics of radiance to an FPGA  
> with a view to (near-)realtime rendering from AutoCAD or similar. I'm  
> currently evaluating previous work in this area, and so far it appears  
> that the most difficult bit of the problem would be the hardware  
> implementation of complex functions for procedural textures and  
> surface models - in particular the generic lookup tables for images /  
> function data. Other than that it's just a lot of legwork... am I  
> missing something?
>
> Has anyone tried this in the past? Perhaps a different type of  
> hardware acceleration? Please let me know if you've got any success /  
> horror stories! :)
>
> mike
>
> ps: Another major problem for point + shoot rendering from 3D modeling  
> programs is ensuring oconv has a bounded finishing time for any given  
> model. Most models I work with in AutoCAD or Lightwave (exporter  
> coming Real Soon!) need extensive conversion work before oconv will  
> run to completion. (Most often it simply runs continuously until it  
> dies because it uses up all available memory. >4GB! ) Are other people  
> having similar problems?