Post-Processing

Light Beams

Light Beams creates volumetric god ray effects, simulating light streaming through atmosphere. Bright areas emit rays that radiate from a configurable light source position.

Example Configuration

light-beams.json

{
  "effect": {
    "postProcesses": [
      {
        "id": "pp_beams",
        "type": "light-beams",
        "enabled": true,
        "settings": {
          "lightX": 0.5,
          "lightY": 0.5,
          "exposure": 0.3,
          "decay": 0.96,
          "density": 1,
          "intensity": 1
        }
      }
    ]
  }
}

Settings

Property	Type	Range	Default	Description
`lightX`	number	0-1	0.5	Light source X position
`lightY`	number	0-1	0.5	Light source Y position
`exposure`	number	0-1	0.3	Ray brightness
`decay`	number	0.9-1	0.96	Ray falloff rate
`density`	number	0.5-2	1	Ray density/spread
`weight`	number	0-1	0.5	Sample weight
`samples`	number	10-100	50	Quality (more = smoother)
`threshold`	number	0-1	0.5	Brightness threshold for rays
`intensity`	number	0-2	1	Overall effect intensity
`animated`	boolean	-	false	Enable particle animation
`particleAmount`	number	0-1	0.3	Particle density
`particleSpeed`	number	0-2	0.5	Particle movement speed
`particleSize`	number	0.5-3	1	Base particle size

Suggested Presets

Style	Settings
Sunburst	lightX: 0.5, lightY: 0.2, exposure: 0.4, intensity: 1.2
Window Light	lightX: 0.8, lightY: 0.3, exposure: 0.3, decay: 0.94
Dramatic	exposure: 0.5, intensity: 1.5, threshold: 0.3, samples: 80
Dusty Rays	animated: true, particleAmount: 0.5, particleSpeed: 0.3

API Usage

render-request.json

POST /api/v1/render
{
  "state": {
    "canvas": {
      "aspectRatio": "16:9",
      "backgroundColor": "#1a1a1a"
    },
    "layers": [...],
    "selectedLayerId": null,
    "effect": {
      "effectId": "none",
      "enabled": true,
      "postProcesses": [
        {
          "id": "pp_1",
          "type": "light-beams",
          "enabled": true,
          "settings": {
            "lightX": 0.3,
            "lightY": 0.2,
            "exposure": 0.4,
            "threshold": 0.4,
            "intensity": 1.2,
            "samples": 60
          }
        }
      ]
    }
  },
  "format": "png",
  "width": 1920,
  "height": 1080
}

Tips

Position light source where bright areas exist in the image
Higher samples = smoother rays but more processing
Lower threshold creates rays from dimmer areas
Enable particles for atmospheric dust/fog effect
Works great with high contrast images