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View Full Version : HP's Polynomial Texture Mapping (PTM)



Ninja
06-28-2002, 01:03 PM
I've been taking a look at some of the work being done on PTM like texture
mapping. Has anyone used anything like this in an actual game? It seems
like it would be a rather promising technique.

Anyone know anything about it or where to find more info about it (except HP's homepage)?

-Ninja

V-man
06-29-2002, 02:40 PM
Where it's being used :
http://www.techtv.com/news/computing/story/0,24195,3369766,00.html

You can also surf through Siggraph papers. I'm not sure what year.

V-man

marcus256
07-01-2002, 12:03 AM
I believe that (today) PTM must be perfromed entierly in software, meaning that it is not well suited for games. I too think that it's an interesting technique, which could probably be used to produce all kinds of interesting effects.

davepermen
07-01-2002, 01:10 AM
actually ptm is quite easy in hardware, just eats up 2 or 4 textures (or 8? http://www.opengl.org/discussion_boards/ubb/wink.gif), so we need to redesign the whole shader.. but its working yet.. nvidia demo is out (download cgshader thingthong.. there you'll see it)

Ninja
07-01-2002, 01:47 AM
what is that demo called?
can't fint any..

davepermen
07-01-2002, 02:16 AM
hm.. its the horizon mapping sorry. but i thought its the same..
anyways, this one is the horizon mapping.. http://developer.nvidia.com/dev_content/cg/cg_examples/pages/bump_horizon_mapping.htm

i thought they mentoied hp there in as well..

anyways.. polynomial texturemapping can be done in todays hw. i'm pretty sure about this.. i'll look for some papers and think about some implementation..

but the most difficult part of the polynomials is not the rendering actually but the generation.. bumpmaps and diffuse textures are easy, but for polynomials you should model with materials and all the actualy geometry and then render from all sides.. ====> need a max-plugin http://www.opengl.org/discussion_boards/ubb/wink.gif

JasonM [ATI]
07-01-2002, 09:03 PM
PTMs can absolutely be done on today's hardware. The reconstruction takes only a few multitexture operations. The real trick to adoption of PTMs is the art path, which is non-existent in commonly-available tools.

-Jason

marcus256
07-04-2002, 03:02 AM
Originally posted by JasonM [ATI]:
PTMs can absolutely be done on today's hardware. The reconstruction takes only a few multitexture operations. The real trick to adoption of PTMs is the art path, which is non-existent in commonly-available tools.

-Jason

I guess this will be added to my list of cool thing to do then, once I get my hands on a GF4 http://www.opengl.org/discussion_boards/ubb/wink.gif

jwatte
07-05-2002, 08:04 AM
You don't need a GF4 to do PTM. At least as far as I recall PTM:
Specify the coefficients of a polynomial per-texel; specify the "x" to evaluate the polynomial with when you render (or per-texel from another polynomial, I suppose).

If you're OK with a grayscale PTM, you can do a quadratic polynomial in a single DOT3 texture operation. Set up your color r/g/b as 1, x and x*x. Then the r/g/b of the texel are the coefficients c, b and a in the polynomial ax2 + bx + c.