Start
Use your own image or open the bundled sample.
WebGL Shader Art Generator
Relight photos with soft window projections and flowing water caustics.
Runs locally No upload
Check this browser
Facts
- Category
- Motion
- Works with
- Image
- Exports
- PNG / JPEG / Video
- Runs in
- Your browser, and the SHADR iPhone app
- Your images
- Processed on your device, not uploaded
- Cost
- Free in the browser
Use light, feedback, and refraction as the source material.
Light Cast is a free browser tool that relights a photo with soft window light, water reflections and other projected light patterns.
Shape
Build the result with Light Type, Distortion, and Palette, then refine the remaining controls in real time.
Export
Render PNG / JPEG / Video output and download it directly to your device.
Use it for
- Generative motion backgrounds
- Shader-led identity studies
- Synthetic cover and title artwork
Key controls
- Light TypeChoose Window Light, Water Light, and Liquid, plus 4 more variations.
- DistortionTune from 0% to 100%.
- PaletteChoose Carbon White, Sodium lamp, and Cobalt Blue, plus 3 more variations.
All controls4
- GrainTune from 0% to 100%.
On the Web
- Export motion as video instead of Live Photo.
In the iPhone app, Live Photo export is available.
Get the iPhone appHow Light Cast works
The photo is lit by a pattern of projected light that you choose. Light Type sets the kind of light (Window Light, Water Light, Liquid, Signal, Prism, Caustics or Vortex). Light Strength (0–100), Light Softness (0–100) and Exposure (0–100%) set how bright and how soft it is, and Light Position X, Light Position Y, Light Direction (-90 to 90) and Light Scale place and size it.
Distortion, Refraction and Dispersion (0–64px) bend the picture through the light, and Palette sets its colour (Carbon White, Sodium lamp, Cobalt Blue, Iris, Acid Green or Custom). The light can move: Flow speed (0–100%) sets the flow, and the motion exports as video in the browser and as a Live Photo in the iPhone app.
Choosing a photo
Photos with some smooth surfaces and a clear subject let the light show: portraits, interiors and still lifes are typical.
Settings worth changing first
- Light Type: Window Light, Water Light, Liquid, Signal, Prism, Caustics or Vortex.
- Light Strength (0–100, default 82) and Light Softness (0–100, default 22).
- Light Position X (0–100, default 53), Light Position Y and Light Direction (-90 to 90, default -24).
- Palette (6 options) and Exposure (0–100%, default 58%).
Presets
Window Light, Late Window, Soft Window, Water Light and Fine Caustics.
Before you start
What are caustics?
Caustics are the bright, shifting patterns of light that form when light passes through or reflects off a curved, transparent or watery surface, like the net of light on the bottom of a pool. Caustics and Water Light are two of the light types in this tool.
How do I move or aim the light?
Light Position X and Light Position Y (0–100) place it, Light Direction (-90 to 90) turns it and Light Scale (0–100) sets its size.
Can I animate the light?
Yes. Flow speed (0–100%) sets how fast it flows. In the browser the motion exports as video; Live Photo export needs the iPhone app.
What can I export?
PNG or JPEG at 1600, 2200 or 3200 pixels on the long edge, or video. The photo is processed in the browser and is not uploaded.
What changes on the Web?
Export motion as video instead of Live Photo.
Continue with SHADR on iPhone after you create in the browser.
Get the iPhone app