Making a Voronoi Texture affect where an image texture is placed on a model?

Question

I have made a simple rock object. I have added bump map, SPEC map and the diffuse texture. I want to make the rock's texture have variation in its texture. I want to add a voronoi texture that will affect what areas of the model will have the image diffuse texture, and the other parts of the model, I want to be in different saturation. Therefore I want variation in the image texture. So some areas are lighter and more saturated, and the other areas have the diffuse color of the image texture.

Here is my node setup.

I want to make this, because it will add more variations to the texture of the model.

Answer 1

You can add a Color > Hue Saturation Value node and plug the voronoi texture into the Saturation socket. Values on the voronoi texture closer to 1 will make those areas of the diffuse texture closer to the original saturation, values closer to 0 will be more saturated.

You can add a Color Ramp node after the Voronoi texture to have better control.

Answer 2

Differentiate diffuse map into 2 shaders and control them with mask

In order to make different parts of model being saturated in a different way which is controlled by Voronoi texture, use 2 shaders and plug that texture as a mask.

In the node setup mask is plugged into the Factor input of the Mix Shader:

It makes bottom (saturated) shader affect where the texture is bright and viceversa.
Resulted shaders - top, bottom and masked:

Answer 3

You can do this by adding a voronoi texture and using its "fac" output as the mix controller for the mixing factor of image textures.

Add the Voronoi Texture.

Pluck its factor into the factor of the MixRGB node.

Add Image texture node and plug it into the MixRGB node.

Hopefully this will do the trick