Global Dirt is a full-screen effect for Unity's Universal Render Pipeline that ages your whole scene in one click. It adds surface dirt, settled dust, moss, metal aging and rust, plus subtle color variation, without touching your materials, your shaders or your art: add one renderer feature and one volume override, raise a slider, and the entire scene gets older.
Key features
Five effects: dirt, dust, moss, metal aging and rust, each with its own colors, size, coverage and placement rules
Smart placement: deposits follow shelter, cracks and world orientation, so dust settles where it would fall, dirt gathers where rain never washes it away, and moss and rust favor the sheltered side
Real surface sets: moss and rust are PBR deposits with their own color, roughness and relief, anchored in world space
Metal aware: aging and rust only reach metallic surfaces, driven by the metalness the GBuffer already holds
Color variation breaks the repetitive look of large surfaces with hue, saturation and brightness variation
Bioluminescent moss: HDR emission from the moss alone, ready to feed Bloom
Dry, Grimy and Abandoned presets give you a complete look in one click, ready to be adjusted
Zones: give an area of the scene its own settings, or limit the effect to it, with soft borders and no mask texture
Per object: one component anchors the dirt to a moving object, keeps an object clean, or gives it its own profile
One master Intensity slider drives everything, even from script
