Dirt Map in viewport

Like the title says.

I want to be able to see a dirt map in the viewport.

An example:
I have an object with VRaylightMtl applied with a VRayDirt map. If realistic materials is ON, the object just displays black in the viewport. For that material if I disable realistic material in viewport it shows the colour of the lightmtl but not the dirt map.
If I go into the dirtmap, I have no option of displaying it either way as the icon is disabled in material editor. If I go one level up, the icon becomes avalable again.
But still, I can’t either way see the dirt map in viewport

Well, the dirt requires raytracing, so it needs the acceleration data built by V-Ray, which is only available during rendering.

We could just show the unoccluded color through - would that be enough?

Best regards,
Vlado

yes that would be perfect thanks