water question

[JanHH]

Hello,

I am planning to do water (ocean size, not pond) simply as a dark blue bump mapped surface (bump mapping of course with shininess) with the wave surface shape as the bump map (no reflections, environment mapping etc.). This sounds quite easy, so I wonder what you guys (and girls) think about it!? Is there a chance of getting a good result?

Thanks
Jan

[Zeno]

Unfortunately, I think your water will come out looking like plastic if you just make it a bump-mapped surface with specular.

IMHO, the single most important optical phenomena in water is the Fresnel reflection. You have to have at least that to get it to look right. If doing the actual reflection is too much for some reason, I bet it would still look good just using the Fresnel term to interpolate between 2 colors (approximate sky color and upwelling color).

[JanHH]

I already thought about "might it look too much like plastic?", but somehow I have the impresion that "ocean" water does in fact look like plastic a bit (for example http://www.cs.utah.edu/~michael/water/deepWater1.jpg), and at least it would be a starting point, I do not know anything about water rendering, have never done bump mapping (and of course don't know what the fresnel equation ist *g*). Isn't it quite hard to do the "actual reflection"? How would that be done anyway, environment mappint? What is _the_ way to do cool water at the moment?

Sorry for my lack of knowledge and thanks,
Jan

[AdrianD]

i don't think the water in this screenshot looks like plastic...
however, if you need more infos about water rendering try this:
http://www.gamasutra.com/gdce/2001/j...jensen_pfv.htm
(an article called "Deep-Water Animation and Rendering")

[SirKnight]

This guy has a really cool ocean demo based off of that gamasutra articles and a few others. Here's the link: http://meshuggah.4fo.de/ He uses vertex programs and register combiners for all of it.


-SirKnight

[JanHH]

thanks :-) in the gamasutra article, the guy also talks about rendering the surface to a bump map. So I guess I could at least _start_ with this? Or is this a totally useless effort and I will have to rewrite all of it later?

Jan

[SeskaPeel]

For information, you can see here what I made with Fresnel, bump mapping, cubic reflection, and cubic diffuse lighting : http://dev.succubus.fr/Shot1.JPG

All this runs in a heavy pair of vertex/fragment program.

SeskaPeel.

[vember]

You probably want to incorporate the fresnel effect in some way, even if it's only done at the vertex level.

And to continue on the theme of this thread, this is what my current water implementation looks like at the moment:
http://claes.galaxen.net/ex/images/demo_october2.jpg

There is a dx9-demo (nv20+) as well if you look around, but it might be a little weird atm as it is a work in progress..

I'm using a fresnel texture-lookup, cubemap and all calculations are done in a linear-colourspace. The geometry is based on a perlin noise derivative, and done on the CPU with a projected-mesh concept that i'm developing.

[This message has been edited by vember (edited 10-23-2003).]

[Zeno]

Well, geez, if everyone else is going to post screenshots, I better get mine in too:

http://www.sciencemeetsart.com/wade/Projects/WaterFX2/

[JanHH]

thansk for all your replies . zeno, your screenshots show about what I'm trying to achieve. I'm still naive enough to believe that simple bump mapping (with specular of course) and the bump map constructed from the water surface geometry should look at least a little bit like that, am I so wrong?

Jan