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Sorry if this is basic, but I'm trying to randomly assign/shift the UV coordinates of a single wood material on approx. 125 separate planks/panels in a wall so that there are no repeating patterns. This is an imported model, so I can't use an Octane Scatter object or a MoGraph object (I've tried a Fracture object, but I couldn't get a result).
Can someone point me in the right direction?

Osl is the right way to look.

Hi pcoombes

Well, for some reason builtin RandomColor node is not "seeing" the instanceID numbers in a Fracture setup but OSL does.
Instance Range works too.

This great script from Beppe should do exactly what you need.
https://render.otoy.com/forum/viewtopic.php?f=73&t=69211

You can use this instead of RandomColor node. It will work with Fracture + Explode segments. Or, for example, as an input in Gradient node (complex mode) to randomize (multi)textures.

Code: Select all

#include <octane-oslintrin.h>
shader RandomInstanceColor(
      int Seed=0,
      output color c = 0)
{   
      c = noise("cell",_getinstanceid(),Seed);
}

With this one you can mask individual objects based on ID. You will see that InstanceIDs mach Index numbers exactly.

Code: Select all

#include <octane-oslintrin.h>
shader InstanceID(
      color A = 1, color B = 0,
      int InstanceID = 0 [[int min=0, int slidermax=100]],
      int Swap = 0 [[string widget = "checkBox"]],
      output color c = 0)
{
   color outA = A;
   color outB = B;
   
   if (Swap==1) { outA = B; outB = A; }
   c = (InstanceID==_getinstanceid())? outA: outB;
}

Cheers
Milan

Thanks, Milan, that's exactly what I needed.
And thanks Beppe!
It's a shame one has to resort to scripting to get something fairly common to work.

Cheers

Big thanks Milan for sharing the RandomInstanceColor.osl node
I have updated my post here with .orbx and .c4d example files.
Happy GPU Rendering,
ciao Beppe