Hi,

I was curious as to whether there were any plans for including something
like the Blinn reflection model in POV-Ray:

http://www.siggraph.org/education/materials/HyperGraph/illumin/specular_high
lights/blinn_model_for_specular_reflect_1.htm

The reason I ask is I'm looking for a way to accurately render from a
distance a surface ( basically a height field ) consisting entirely of
rectangular legos.  A 'distance' means that in a given frame of an animation
there would be more lego parts on the surface than pixels in the rendered
frame, and enough legos that modelling each lego explicitly with CSG would
be prohibitively expensive in terms of memory use.

The alternative is to try to apply a finish to the height field that
simulates how the blocky, bumpy lego texture would behave: some light in a
given ray would bounce off the facets on the sides or tops of the lego
bumps, and some would bounce off one of the sides of the main rectangular
component.  Some of the reflected rays would be occluded by bumps, or by
other legos, at certain camera and light source angles.

The blinn model allows simulation of this via a (relatively) simple
equation, where the statistical distribution of facet normals, degree of
occlusion, and fresnel reflective properties are quantified.

First, am I overlooking some easier way to do this?  Second, would a patch
to POV 3.1 to add support for the blinn model be a welcome thing (I am on
linux right now and there doesn't seem to be an easily acessible 3.5 version
for linux at the moment)

Thanks

Brian Dunstan

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