Hi TAN TOH FEI,
> I'm just wondering what sort of technique is being used for Volume Rendering
> in VisAD. Is it "Splatting", "Spatial Technique", "Blending" or something
> else? Hopefully someone can answer my doubt. By the way, may I know which
> particular file(s) in VisAD package is attached with this Volume Rendering
> code. Thanks n Cheers.
The technique is to render a cartesian grid as a series of
transparent planes, aligned to the axes most nearly
perpendicular to the view direction (so the planes change
as you rotate in 3-D).
This technique was first described by my 1989 paper with
Dave Santek:
Hibbard, W., and D. Santek, 1989; Interactivity is the key. Chapel Hill
Workshop on Volume Visualization, University of North Carolina, Chapel Hill,
39-43.
The technique is now widely used, since it exploits graphics
hardware for fast volume rendering.
The code for implementing it in VisAD is in
visad/ShadowFunctionOrSetType.java (look for code inside
"if (isTexture3D) { ... }") and in
visad/java3d/ShadowFunctionOrSetTypeJ3D.java in the
textureStackToGroup() method.
This technique is also used for the volume rendering demos
distributed with Java3D.
Cheers,
Bill
----------------------------------------------------------
Bill Hibbard, SSEC, 1225 W. Dayton St., Madison, WI 53706
hibbard@xxxxxxxxxxxxxxxxx 608-263-4427 fax: 608-263-6738
http://www.ssec.wisc.edu/~billh/vis.html
