Classification:
The Classification stage assigns an opacity to each voxel in the data set. the opacity is a measure of how translucent the voxel is. it is a number bet 0 and 1 and describes how much light that falls on a voxel
will be absorbed by that voxel. tells you how easy it is to see through that voxel. Assigning an opacity to a voxel can be a very complex operation.

Segmentation:
Segmentation is defined as a lalbeling of voxels indicating material types. Thus a voxel is part of one material or another. Segmentation is not continuous like classfication.

hope things work well today.. lets see.. gonna try hard :D
got the prorgam to work.. so Yeah :)
also understand the sphere problem well now. not that bad a day after all

replaced intval = data[index] by its computed value.
trying lighting, but it aint working busta.. :-p
damn man, this lighting thing is just not working ! :(

changed gradient to gradient/2 in gnn and gtri
just sent the program to tony. lets hope it works fine. release mode is awesome !
need to separate diffuse + specular and add conditions for diffuse affecting specular :D

boundary_flag causing problems. alpha/adensity = adensity/10 gives sketches for some volumes (cello)
cant do much if the alpha is either 1 or 0 when performing boundary or silhouette enhancement because those are alpha limits anyway. :D

Hanrahan, Lawson - a language for shading and lighting calculations - siggraph 90
robert cook siggraph 84 - shade trees
lastra, olano acm95 - real time programmable shading
lastra, olano siggraph 98 - pixelflow shading system
proudfoodt, hanrahan siggraph01 - shading language on graphics hw

fixed scaling. problem with scaling and perspective viewing. tried new volumes from the cd. didnt work cos theyve got a diff format. should write a small program to get that working,
so that those vol's can be used..