On Mon, 20 Aug 2001 19:33:58 -0500, Reusser <reu### [at] chorusnet>
wrote:

>Sounds interesting, but what exactly is it (in terms of not what it
>does, but how it works)?  Is it an extension on ray-tracing?  I caught
>that BRDF is bi-linear reflection diffusion function or something on
>that order, but what does that mean?  (Not all of us are able to decode
>the pdf file and figure out what they are talking about.)

If you're talking about BDRF, it means Bi-directional Reflectance
Function. This is a geeky way to say 'material reflectance
properties'. The bi- in the name suggests that it can be used for
anisotropic shading, for example brushed aluminum.

diffuse, specular, phong and even ambient are BDRFs, as is blinn.
There are many different BDRF models aimed at representing different
material properties. Some are very mterial-specific, for example silk,
hair, skin etc.

IIRC programmable shaders a la RenderMan allow for custom BDRFs, which
is a really powerful material creation tool.


Peter Popov ICQ : 15002700
Personal e-mail : pet### [at] vipbg
TAG      e-mail : pet### [at] tagpovrayorg

Post a reply to this message