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pappuftp
08-10-2004, 01:13 PM
How do I achieve falloff ( incident ) reflections in my objects ? I must admit I am pretty naaive when it comes to xsi shaders .. thnx

yog
08-10-2004, 01:33 PM
You can either plug the Incidence node (found in the Illumination node tab) direct into the reflection slot of the shader. Or for more control you can plug the Incidence node into the input slot of a Gradient node (the Mixer gradient, not the texture gradient) and then into the reflection slot of the shader. The gradient then gives you a lot of control in the amount and type of your falloff, it's also very good for colour tinting your reflection colours.

pappuftp
08-10-2004, 02:32 PM
thnx 4 the tip .. seems 2 work.


Also,the anisotrophy shader seems to reallly bleach out my pobjects at default settings and i dunno how get it into control.. any thoughts on that one?

ThE_JacO
08-10-2004, 03:01 PM
anisotropy needs a direction input to work, that means it only works properly with nurbs.
BUT Daniel Rind wrote a brillant shader that can derivate anisotropical friendly coordinates from polygons, so that you can use all those thingies polys never got :)

you can get that and other very useful shaders here:
http://animus.brinkster.net/index.html

his dirtmap is also known to be one of the best AO shaders around.

asylum24
08-10-2004, 04:42 PM
ok i have to ask.... wtf is a dirt shader.. i looked and looked and all i got was "use it" not what it was... so someone please explain please!

ThE_JacO
08-10-2004, 04:50 PM
look up ambient occlusion on google and all your questions will be answered.

yog
08-10-2004, 04:53 PM
ok i have to ask.... wtf is a dirt shader.. i looked and looked and all i got was "use it" not what it was... so someone please explain please!
AFAIK it was originally designed to simulate dirt build up in the corners of your models, think Dosche Dirty-Up, but people have found it is very good at simulating ambient oclussion. Can give a look similar to global illumination, but in a fraction of the time.

Atyss
08-10-2004, 05:26 PM
Occlusion would perhaps be a better term. At XSI Base there are plenty of threads regarding occlusion rendering. Check the How I Did It section for threads started by thebigMuh and wurp. Ambient occlusion is basically using an occlusion shader such as dirtmap to composite a color in the ambient areas of a rendering.


Cheers
Bernard

pappuftp
08-10-2004, 06:59 PM
funny abt the anisotrophy settings workind well on nurbs surfaces coz ( and this is not a flame-war, ok? ) it works pretty seamless on polys in both max n maya .. i tend to use it a lot on my metals and was wondering..

btw XSI rendering rocks!!!

ThE_JacO
08-10-2004, 07:14 PM
funny but not strange, max and maya simply slip into the rendering pipe what in XSI you have to do with Daniel's node.

yog
08-10-2004, 07:42 PM
funny but not strange, max and maya simply slip into the rendering pipe what in XSI you have to do with Daniel's node.
This is one part that really worried me at first, but I have come to REALLY appreciate. Whilst some programs do a lot of the behind the scenes work for you in material creation, XSI exposes you to a lot more of it, daunting at first, but it gives you a fantastic number of options.

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