Palette Canvas

Control lighting in AI-generated images through color gradients and shapes.

<img width="450" height="374" alt="image" src="https://github.com/user-attachments/assets/95160a67-db3a-4487-b35a-5129822bdea7" />

This ComfyUI custom node creates color canvases that serve as lighting maps for text-to-image generation workflows. By encoding these gradients through VAE and using them as initial latents with lowered denoise (0.87-0.95 instead of 1), you can precisely control the mood, atmosphere, and illumination of your generated images.

The Concept

Traditional text-to-image generation gives you limited control over lighting. This node solves that by letting you:

1. Paint with Light - Create custom gradients that define how light flows across your scene
2. Add Light Sources - Place bright shapes on dark backgrounds to create specific illumination points
3. Guide the AI - Feed these light maps into your sampler to influence the final lighting without complex prompting

Use Cases

Atmospheric Lighting

• Create sunset gradients (orange → purple) for golden hour lighting
• Design dark-to-light gradients for cinematic rim lighting
• Build complex multi-color gradients for fantasy scenes

Specific Light Sources

• Place a bright circle on dark background → creates a spotlight effect
• Use rectangle shapes as window light sources
• Position triangles for dramatic angular lighting

Mood Control

• Cool gradients (blues) for night/calm scenes
• Warm gradients (reds/oranges) for energetic/warm scenes
• High contrast gradients for dramatic noir lighting

Installation

Method 1: ComfyUI Manager (Recommended)

1. Open ComfyUI Manager
2. Click "Install Custom Nodes"
3. Search for "Palette Canvas"
4. Click Install

Method 2: Git Clone

cd ComfyUI/custom_nodes git clone https://github.com/yourusername/ComfyUI-PaletteCanvasRGB.git

Method 3: Manual

1. Download this repository as ZIP
2. Extract to ComfyUI/custom_nodes/ComfyUI-PaletteCanvasRGB/
3. Restart ComfyUI

Technical Details

Why Denoise 0.87-0.95?

• 0.87-0.92: Gradient strongly influences the final image composition
• 0.93-0.95: Balanced - AI follows the lighting but creates natural details
• 0.96-0.99: Subtle influence - AI uses gradient as "mood suggestion"

Aspect Ratio Handling

The node automatically corrects for non-square aspect ratios. A circle remains circular whether your canvas is 512×512 or 896×1152.

Shape Distortion (scale_x/y)

Use independent X/Y scaling to create:

• Elliptical lights (stretched circle = wide light source)
• Anamorphic flares (compressed height = cinematic lens flares)
• Custom light patterns (rectangle stretched into line = neon strip)

Requirements

• ComfyUI (any recent version)
• Modern browser (for interactive widgets)

No additional Python packages required.

License

MIT License - See LICENSE file