output a bump map texture, from a base texture

output a bump map texture, from a base texture

Post by Johan "MrD » Fri, 18 Feb 2005 23:19:27


I would like to write an image processing algorithm in c++ for composing
a bumpmap texture out of a base texture. (I want to use its output for
peforming dot product 3 bump mapping based on OpenGL texture environment
combining).
I do not want to do it by using an external image processing app like
photoshop since my textures are procedurally created on run-time. How
could i implement such a filter? Does anyone have some pointers?

thanks, MrDutchy.
 
 
 

output a bump map texture, from a base texture

Post by Johan "MrD » Thu, 10 Mar 2005 23:14:35


In the meantime i have implemented a solution myself. It works perfectly
and it looks better than some of the filters which can be found on the
net. I think this is because those do the finite differencing in only
one direction on each of the x and y axis (which drops a lot of the
surface's "signal" information).

my implementation can be found here:
http://www.yqcomputer.com/

The open source project celestia ( http://www.yqcomputer.com/ ) was a
great help. Also these 2 papers and a nehe article on hw dot3
bump-mapping in OpenGL:
1. Mark Kilgard "A Practical and Robust Bump-mapping Technique for
Today GPUs"
2. nvidia "All the Polygons You Can Eat"
3. http://www.yqcomputer.com/

i just thought i'd drop this information here even if it took me quite
long, maybe it is of some use for anyone later on :)

MrDutchy.