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View Full Version : a place to find materials and/or lights ?



rixed
12-11-2002, 03:04 PM
Hi !
Im working on an ocean rendering, and Im looking for a good material for the sea surface and or a good lighting model for the moonlight (yeah, the sea is by night). I asked google but didnt find anything.

So the question is : is there a place somewhere on the net like an opengl material/ligthing model repository with good parameters for common things ?

If not, what would be good parameters for moonlight on sea surface in your opinion ?

Anyway, someone knows about a material/light editor (i would need a tool to play with material parameters, colors, lightning model, and quickly see the result) ?

rgpc
12-11-2002, 03:32 PM
So google didn't find gmax? You didn't find any Lightwave/3DStudio Max/Maya/etc. tutorials on lighting?

Are you at least using OpenGL?

fritzlang
12-11-2002, 03:34 PM
If you are doing an ocean I think you should work with procedural waves and animated noise. And use delicate perpixel lighting techniques to create the dynamics, and then perhaps feed that through various diffuse / specular colors. If it is far away and static, use an image of an ocean and simply texturemap it, perhaps perspective-projected. If it is moving, animate the texture.

fritzlang

SirKnight
12-11-2002, 06:20 PM
There is a great article on ocean rendering on Gamasutra.com. Someone made a demo using nvidia's effects browser that does very nice looking ocean rendering in realtime and he used that gamasutra article in additon to a few other sources for things. This demo I speak of should be on developer.nvidia.com somewhere.

-SirKnight

SirKnight
12-11-2002, 06:26 PM
Well I don't know where the heck nvidia stuck the link to those demos that guy did, with one of them being the ocean effect, but I found the link to his hopepage. Here it is: http://meshuggah.4fo.de/ I hope that will be of some interest. I know this person's demos interest me quite a bit. They are pretty cool. http://www.opengl.org/discussion_boards/ubb/biggrin.gif

-SirKnight

rixed
12-12-2002, 02:04 AM
rgpc : Im using openGl, and when I ask for a material in an opengl oriented forum, I actually ask for the ambiant/refraction/primary and secondary/etc glMaterial parameters.
So I dont think Max or Maya would help, or do they use the same parameters (that is : do they show to their user the value for those opengl parameters ?)

Fritzlang : The view is close to the sea level, and I already animated the waves (and Im quite happy with animation). What I need now is to find a material and a lighting model. Noise will be for the bumpmap texture, not for the material.

SirKnight : Im gonna look for the article. Ive watched the screenshot of the demo you linked to, and it looked quite like what Im trying to achieve. Im gonna look for the article to see if it tells something about material parameters and/or lightning model.

Thank you all !

If I don't find, I gonna write a little tool to change material and lightning properties with a mouse for clic clic. Like thoses already existing for BMRT. (look for tkMatMan)

Oh, by the way : if someone is interrested, I challenged some friends of mine to render an ocean at sea level. If some of you want to enter the competition, let me know :-)

Ysaneya
12-12-2002, 05:37 AM
My small contribution to ocean rendering:
www.fl-tw.com/opengl/ocean1.jpg (http://www.fl-tw.com/opengl/ocean1.jpg) www.fl-tw.com/opengl/ocean2.jpg (http://www.fl-tw.com/opengl/ocean2.jpg) (wireframe)

Unfortunately many demos rely on a heavy mesh to render their ocean, so it's not very usefull for a game. I tried to get away with a couple thousand polys only (i think it's 4096 in these shots). Lots of per-pixel effects; if i remember correctly (i wrote it many months ago!) i was doing per-pixel reflection into a cube-map, per-pixel fresnel and refraction into a deep-water cubemap.

The mesh was animated with a Perlin noice function, which gave surprinzingly good results compared to my FFTs tests..

Y.

Mazy
12-12-2002, 06:00 AM
rixed : Yes, most of the more lowlevel material properties in those 3d programs are pretty much like the opengl properties.. I think many people ( including me) can create the materials directly in a 3d program, export it and use it in the opengl renderer.. some adjustments may be done, but its not very hard.

rixed
12-12-2002, 06:15 AM
Ysaneya : Nice pic ! the wire looks poor (at least, you wanted it this way), but the rendering is nice anyway ! OK, you are added to the list of competitors http://www.opengl.org/discussion_boards/ubb/smile.gif Is the code or executable available somewhere ?
I would like to see the perlin noise in action !
the mesh I use for now have about 20000 vertices with 2 LODs http://www.opengl.org/discussion_boards/ubb/frown.gif I use severall tricks for animation, and get satisfying results for waves.

Mazy : Yeah, I done this with blender when I used it. Now I use realsoft3D for modeling and its very ray-trace oriented so finding opengl parameters is not trivial (procedural materials, very sophisticated lighning).

Mazy
12-12-2002, 06:43 AM
Hum, dont use procedural material properties.. just use the normal Ambient/Diffuse/Specular/emission and a decal texture, plus lights and what else you have in your program.. you know the limitations of your engine, so dont go over those boundaries.

rixed
12-12-2002, 07:12 AM
Mazy : I do not use those things, its realsoft3d which does :p