The Unlit mode in the Diffusion shader module disables all interaction with scene lighting. Surfaces using this shader display only their assigned color or texture, remaining uniformly visible regardless of lighting conditions. Unlit materials ignore diffuse, specular, and shadow calculations and render consistently across all environments, since no lighting affects them.

Some use cases for the Unlit shading model include:

• Special effects such as glows, outlines, or stylized graphics.
• Backgrounds, skyboxes, or UI elements that should not react to lighting.
• Debugging textures or UV layouts.