Switchers For Randomizing
Patterns In 3dsmax By Neil Blevins Created On: Dec 10th 2013 Updated On: Dec 9th 2024
Software: 3dsmax Lets say you have a bunch of rocks in a scene, and you want
to give each rock a slightly different color to add variety. What you
need is a switcher. What is a switcher? Basically, you define
a set of patterns, and they get assigned to specific groups of objects,
faces, etc, usually using some sort of ID value that connects the
pattern to the thing its being applied to. So for example, you create a
rock material that has 5 different rock colors, and then spread
randomly the ID 1 to 5 on a bunch of rocks, and each rock receives one
of the 5 rock colors.
Which Switcher To Use
If you want to apply completely
different materials to these objects, you'd use a material switcher
like the sub-object Material. But since we only want to vary the color,
and leave the rest of the material alone, what we need is a map
switcher. Sadly, there's no one map switcher that works in all
renderers. Here's the available map switchers...
3dsmax Vray: VrayMultiSubTex
3dsmax Vray: VrayHDRI
3dsmax Scanline and Vray: MultiIDMap by Grant Adam which
is a free plugin that can be found at http://maxplugins.de/
For this tutorial, I'll use the VrayMultiSubTex, but the same basic
technique works in all of the switchers, use whichever one works with
your renderer of choice. For more information on which Switcher map to
use and which ID type to choose, look at the spreadsheet on Switchers And IDs,
Which To Use When. You also should download my Soulburn
Script pack, as I'll be using the iDSetter Script.
Using VrayMultiSubTex
So here's the basic process...
Method 1: If you have a bunch of seperate objects, say a bunch of
seperate rock objects, first, select your
rocks.
Run my iDSetter Script.
Set Low to 1 and High to 5. Hit Apply. Now inspect the rocks. Each rock
has a Material modifier on it with a random Material ID from 1 to 5.
Method 2: If you have a single object that contains a bunch of
subobject elements, and you want each element to be different, select
your object, and assign a
MaterialByElement modifier.This will assign a random Material
ID per element (each rock).
Now that we've got the Material IDs assigned, lets assign a single rock
map to the diffuse of the rock material...
Now put that rock bitmap map as a submap of VrayMultiSubTex. Set Num
IDs to 5.
Now you can fill in the 5 slots with 5 completely different rock
textures, or if you just want some color variation, put 5
ColorCorrection maps in the 5 slots, hook all 5 ColorCorrection maps to
your original bitmap, and then tweak the color on each map slightly,
making some darker, some lighter, some browner, etc.
And here's the result...
Now remember, since the rocks are all keyed off the Material IDs, if
the directors says "I love it, but can you make that rock closest to
camera one of the browner ones?" You can, just select that rock, and
change the Material ID in the Material modifier to be one of the
browner variations.
Using MultiTextureMap
Amir Naziri reminded me about CG Source's MultiTextureMap. This is
another type of switcher that's available here: http://www.cg-source.com/multitexture.php
It lets you take a bunch of maps, and randomly assign them to a set of
objects using Material or Object ID. Or, you can load a single map, and
play with the Random Color Adjustment to have each be a slightly
different color / brightness / saturation. This plugin does have a few
limitations though...
Only works with bitmap textures, not procedurals, and no map
chains
Limited number of bitmap options, so no stuff like cropping or
Rotation built into the map.
But it's certainly a useful plugin that may do exactly what you need in
some instances, and is worth checking out.
Other Techniques
Urs Dubacher
pointed out a few other scripts and plugins that can help with creating
random variation:
Check 'em out if you want even more ways of achieving variation.
Conclusion
Remember, when you have a bunch of similar things, they're never all
exactly the same, there's always subtle color variation and texture
variation, even if they're all the same sort of rock, grass, wood
planks on the kitchen floor, etc. The colors in the example above may
be a little exaggerated to show the point, but even subtler variation
can give a lot of life to your scene. So always use a switcher to give
it a
little variation.
