Shader? Color in relation to elevation of form

[duck2001]

I am trying to produce a scene with the look of a 3-D topographic map based on Maya procedural shaders rather than image maps. Does anyone know of a way to make a shader whose color (representing elevation) will change based on the height of a model. It seems like it would be easy, but I just can't figure out the best way to do it. Can anyone offer advice? Thank-you in advance.

David Duckworth

[xgc]

quite simple I suppose, just use...
hieght maps, for the terran, and then apply a color to the highmap, and apply that to the color channel...

however, if you have already dont the terran, then i'm sure some type of expression or script will do it too.

[duck2001]

That could definately work as an alternative, however I am trying to work back from the existing model. I will try to mess around with the expression editor. If anyone has any more details or suggestions they would be greatly appreciated. Thank-you!

David Duckworth

[stevesayer]

Create a Ramp texture and then project it onto your model from the side.

Good luck!

-Steve

[joojaa]

Well the height is stored in a black and white format (for the displacement??, if not then use the method below) so then just connect this to ramp and connect this to your color. YOu might even consider giving the ramp a slight noise so that the change isnt so uniform

Or then use sampler info world x, y or z depending on how your model is set up

[xgc]

OMG, I didn't even like think about ramps... lol... when he ask jeez... thats the simpliest thing ever, but does it work well??

[nightshadevfx]

Connect the black/white displacement map to the ramp how? Using a remap?

[xgc]

no, like, start with a plane, and set the hieght map to the accurate hieght settings, and apply it to the color map, so the higher the terran, the whiter it'll be...

but I dont really know how to make a hieght map, but I'm SURE there is one...

[ggray7]

One method:
Connect Object Y from Sampler Info node to a set range, then to the V of a ramp. Use the set range to convert from 0 to whatever the max height of the object is to a 0 - 1 for the ramp. This will give shading based on height.

Something else to try:
The snow 3d texture node for slope based shading
or
Make your own slope shader by comparing the surface normal to the Y axis(assuming Y is up). Feed that into a ramp.

Of course any high detail terrain stuff can be a hassle in maya due to lack of nice displacement(micropolys)... time for renderman

~Garret