[comp.graphics] Material constants for Phong lighting model

glenn@smosjc.UUCP (Glenn Poole) (05/14/91)

I am working on a rendering system using the phong lighting model.
The lighting equations we are using are similar to:

Cobject= Cambient + Cdiffuse*Clight*(N.L) + Cspecular*Clight*(N.H)^n

Where:

	N.L is the dot product of the normal vector and the light vector
	    (N and L both normalized)

	N.H is the dot product of the normal vector and the half-way vector
	    which is halfway between the L and V vectors.  
	    (N and H both normalized)

	n is the "specular exponent"

This is essentially the textbook formulation, as found in Foley & vanDam 2nd Ed,
pages 722-731, except they separate the coeficients into a product of
coefficients, such as: Cambient <=> IAlambda* KA* ODlambda.

Now for the question:  Does anyone know where can I get a list or library 
of material properties for some common materials, such as wood, paper, 
plastic, brushed aluminum, etc?  Best would be a computer file with 
the Cambient, Cdiffuse, Cspecular and n parameters for a variety of 
interesting materials.  A list in a book would also be good.


Thanks in advance.

Glenn Poole
S-MOS Systems, Inc
San Jose, CA

mark@calvin..westford.ccur.com (Mark Thompson) (05/15/91)

In article <648@smosjc.UUCP> glenn@smosjc.UUCP (Glenn Poole) writes:
>Now for the question:  Does anyone know where can I get a list or library 
>of material properties for some common materials, such as wood, paper, 
>plastic, brushed aluminum, etc?  Best would be a computer file with 
>the Cambient, Cdiffuse, Cspecular and n parameters for a variety of 
>interesting materials.  A list in a book would also be good.

"Illumination and Color in Computer Generated Imagery" by Roy Hall is
an excellent book for describing the problem of realistic surface rendering
and has a number of tables, plots, and guidlines for rendering various
materials. In Hall's book, he references Purdue University (1970)
"Thermophysical Properties of Matter", Thermophysical Properties Research
Center, for the various spectral curves and data for a multitude of
materials.

Hope this helps.
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