Lighting & Post-Processing

Overview

Unity lighting setup and post-processing effects for atmosphere, mood, and visual polish. Covers URP and HDRP Volume system.

When to Use

•Use when setting up scene lighting
•Use when adding visual polish (bloom, vignette)
•Use when creating mood/atmosphere
•Use when optimizing lighting for performance
•Use when baking lightmaps

Architecture

code

┌─────────────────────────────────────────────────────────────┐
│                    LIGHTING SETUP                           │
├─────────────────────────────────────────────────────────────┤
│                                                             │
│  DIRECT LIGHTS           INDIRECT LIGHT                    │
│  ┌──────────────┐       ┌──────────────┐                   │
│  │ Directional  │       │ Lightmaps    │ (Baked)          │
│  │ Point        │       │ Light Probes │ (Dynamic obj)    │
│  │ Spot         │       │ Reflection   │ (Specular)       │
│  │ Area (Baked) │       │ Probes       │                   │
│  └──────────────┘       └──────────────┘                   │
│                                                             │
└─────────────────────────────────────────────────────────────┘

┌─────────────────────────────────────────────────────────────┐
│                  POST-PROCESSING STACK                      │
├─────────────────────────────────────────────────────────────┤
│  Volume (Global/Local) → Profile → Effects                  │
│  ┌────────┐ ┌────────┐ ┌────────┐ ┌────────┐ ┌────────┐   │
│  │ Bloom  │ │ Color  │ │Vignette│ │ DOF    │ │ Motion │   │
│  │        │ │ Grade  │ │        │ │        │ │ Blur   │   │
│  └────────┘ └────────┘ └────────┘ └────────┘ └────────┘   │
└─────────────────────────────────────────────────────────────┘

Light Types

Type	Use Case	Shadows
Directional	Sun, moon, main light	✅
Point	Lamps, fires, orbs	✅
Spot	Flashlights, spotlights	✅
Area	Soft room lighting	Baked only

Post-Processing Effects

Effect	Impact	Use
Bloom	Medium	Glow, HDR highlights
Color Grading	Low	Mood, LUT
Vignette	Low	Focus, atmosphere
Depth of Field	High	Focus effect
Motion Blur	High	Speed feeling
Ambient Occlusion	High	Contact shadows
Screen Space Reflections	High	Reflective surfaces

Best Practices

•✅ Use Global Volume for base settings
•✅ Use Local Volumes for area-specific effects
•✅ Bake static lighting for performance
•✅ Use Light Probes for dynamic objects
•✅ Keep bloom subtle (intensity < 1)
•❌ NEVER use real-time shadows for all lights
•❌ NEVER enable all effects on mobile
•❌ NEVER over-saturate color grading

Few-Shot Examples

Example 1: Sunset Mood

User: "Create a warm sunset atmosphere."

Agent:

code

Directional Light:
- Color: RGB(255, 180, 100)
- Intensity: 1.2
- Rotation: X=15 (low angle)

Volume Profile:
- Color Grading: Warm temperature +20
- Bloom: Intensity 0.5, Threshold 0.9
- Vignette: Intensity 0.3

Example 2: Horror Scene

User: "Dark, scary lighting setup."

Agent:

code

Lighting:
- Directional: Disabled or very dim
- Point lights: Cold blue, low intensity
- Spot: Harsh white for flashlight

Volume:
- Color Grading: Desaturated, lift shadows blue
- Vignette: 0.4 intensity
- Grain: Enable for film look
- Fog: Volumetric if HDRP

Example 3: Stylized Game

User: "Bright, colorful cartoon look."

Agent:

code

Lighting:
- Directional: White, Intensity 1.5
- Ambient: Bright gradient sky

Volume:
- No Bloom or subtle
- Color Grading: Boost saturation +10
- No Vignette
- Consider Tonemapping: Neutral

Pipeline Specific

•URP: Volume system, limited effects
•HDRP: Full feature set, volumetric fog
•Built-in: Post Processing Stack v2

Related Skills

•@shader-graph-expert - Custom effects
•@vfx-graph-shuriken - Particle bloom interaction
•@cinemachine-specialist - Camera DOF