LumiBrush

Quickly design cinematic lighting by painting a dynamic light cookie directly in the scene.

Instead of tweaking multiple light sources, you can place sprites, textures, or painted masks that shape the directional light, giving you fast control over the mood and composition of your scene.

Artists and developers can quickly create cinematic, stylized, or atmospheric lighting without complex lighting setups.

Inspired by lighting design techniques used in visual development and concept art, LumiBrush brings a painting workflow to real-time lighting in Unity.

How it works:

LumiBrush generates a dynamic light cookie for a directional light using a runtime rendering pass.

The system works in two main ways:

• Light Sprites
• Light Painting.

Light Sprites:

Light sprites are placed in the scene and rendered by an camera into a dynamic cookie texture.

That cookie is applied to the directional light, shaping where light appears in the scene.

Because of this approach:

• Light sprites can be moved, animated, or attached to objects
• Lighting updates in real time
• Multiple sprites can be combined to build complex lighting shapes

Light Painting:

LumiBrush also allows direct light painting inside the scene.

When painting:

• A painting surface is created (plane or generated mesh based on scene topology)
• Brush strokes paint vertex colors onto the mesh
• These vertex colors are rendered to the same dynamic cookie texture
• This allows artists to paint where directional light should appear or disappear.

Performance:

LumiBrush works by generating one dynamic light cookie texture for a directional light.

Runtime cost consists mainly of:

A single camera rendering pass that generates the cookie texture

Scene objects used for light sprites or paint meshes

No additional real-time lights are required.

This makes LumiBrush particularly useful for stylized scenes, cinematic lighting, and fast iteration workflows.

Perfect for:

• Atmospheric environments
• Stylized lighting
• Cinematic storytelling
• Rapid lighting iteration
• Prototyping scene mood and composition

Whether you are prototyping or polishing your final look, LumiBrush turns lighting into a fast, creative process instead of a technical chore.