Hi, Like the title says, can I map the scale of a procedural texture?
For example: I would like to use a greyscale image texture to control the Voronoi scale so that in some areas the voronoi cirlces are big and in others they are small but also there is a smooth transition in between.
Thanks!
No, you can’t. At least for getting the results you want.
Scaling a procedural, is simply scaling the coordinate system for the procedural, and not for scaling the procedurals features. This means, that when the gradient of your coordinate system is not uniform, the texture will distort from one point to another.
For example, in the voronoi texture, you need to scale each cell independently, and since you need to access this factor from all other neighbouring cells, you cannot just scale the coordinate system. And for making this change, you need to jump inside the procedural source code and make the adaptation there.
Here’s a similar thread (with an OSL solution)
You can run a greyscale image/texture into the scale slot of the Voronoi. You could also insert a couple of math nodes in between (say an Add to control the overall scale and a multiply to control the scale range).
I have used one texture to modify the scale of another texture in many of my materials.
(edit: of course there are downsides as Secrop describes above).