DIRT MATERIAL - VRAY
The Vray Dirt material utilises the Vray Dirt Texture, stacked in a VrayBlendMtl.
The dirt layer works on an ambient occlusion basis, with a texture used in the radius settings, along with a Vray Colour in the Occluded Colour section.
A good trick to remember with Vray Dirt is to flip the black and white values. This allows you increase the power of the occluded areas by using the Vray Colour node.
Below you can see how the “VDirt” tab is set up within the VrayBlendMtl.
The image on the left is the overall setup. The image on the right is the Vray Color which is piped into the Occluded Colour slot. Note the RGB Multiplier. This is how you increase the power of your VrayDirt occlusion.
The files included in this Material are not using any textures. Layering the Radius input with multiple grunge textures and noise will create very interesting and believable dirt effects. A good way to understand VrayDirt is to think of it as a “Mask or Alpha” being applied to your materials.
The car render below utilises many VrayDirt elements in its materials, from the car paint to metals, plastics etc.
