Applied PitsD (bump only
shader) over the Bricks. Reactive mode for Bump Strength
is set to Desaturated Areas,
so that mortar has more distinctive effect.
Reactive modes are simple and easy to use. You just set the
amount, and choose a reactive mode from popup menu.
With Desaturated Areas mode,
shader effect is stronger over the less saturated areas. Suppose
you set the amount to 1.8. Then, you can get 1.8 over the
zero-saturation areas, while no effect over the 100% saturated