Vray MultiSubTex Random by Name not random...

[Anonymous]

Hi,

I need some help regarding to Random by Name in Vray MultSubTex. I created a floor with instances of planks with all the same VrayMultSubTex material with some different colors.

The floor material randomizes by the start of rendering and during rendering the material turns out the same. See added screenshots.

I want the material to stay randomized, what do I do?

[Anonymous]

Hi ... 

lets say that you need to use 5 different colors to random .. 

-after set an different  ID  for every  single polygon from 1-5 ..

- put the colors you need in multi sub object material ..

-assign " MaterialByElement " from modifier list .. 

-then check the "ID Count"  number  in MaterialByElement modifier it must be the same  number to use all the colors

🙂 

[Anonymous]

Hi thanks for the reply,

When using MaterialByElement modifier it is not necessary to assign IDnr's, thats the whole point of the modifier I think? It assigns randomly a material from the MultiSubObject material to elements of the object.

Without the modifier it is necassary to put IDnr's to the elements.

Anyway, it works now. I created one object with all the planks as elements and used the modifier.

But I still don't get what happens with the other method during rendering in my initial post :S

Thanks!

[Anonymous]

you are welcome ..

I'm not sure if this is necessary  or If there is another way,  but I had watch it in a YouTube tutorial and I am using it in this way 🙂 

I tired to help ..  

[Francisco_Penaloza]

How did you create the 'color variations'?

There are many ways you can do this, one of them is creating a base material and use all the variations as a color overlay (Default option) you can disable this with unchecking the option 'Blend color and texture' . This method sometimes won't create a big difference in color so you need to test and see how it goes.

Other method is creating a different shader per slot or option.

Having said that there are a few modes to randomizing the color selection. If you create one object and instance that object around, then Random by Name or Random by node handle will work fine.

If it is a single object with multiple faces, then you need to add a modifier to assign different ID's per faces.

Sometimes some generator will create many objects but with the same ID, then you need to choose by name.

You can also use 3DMax Random ID modifier as mentioned before.

So not because the multitexture will choose randomly a color selection it means that your mesh will react as expected, this will depend on how the mesh was created.

Hope this help.

[Anonymous]

Hi Francisco.Penaloza,

thanks for your reply.

To create the color variations I created a VrayMtl, with VrayMultiSubTex as diffuse input. That is set to Random by RenderID and it has slots with different colors.

I think it had to do with how the mesh was created, I started from scratch and tried the different methods and now works as expected.