glsl-cornell-box/README.md

the cornell box raymarched in GLSL, for tests

# glsl-cornell-box

[![stable](http://badges.github.io/stability-badges/dist/stable.svg)](http://github.com/badges/stability-badges)

![cornell](http://i.imgur.com/wX030Ti.png)

[(glsl bin demo)](http://glslb.in/s/32a06a02)

The Cornell Box raymarched in GLSL, for testing purposes. [Credit to @h3r3](https://www.shadertoy.com/view/4ssGzS). 

```glsl
precision highp float;

uniform vec2 iResolution;
uniform float iGlobalTime;

#pragma glslify: cornell = require('glsl-cornell-box')
#pragma glslify: camera = require('glsl-turntable-camera')
 
void main() {
  vec3 ro, rd;
  float anim = sin(iGlobalTime);
  float rot = anim*0.1;
  float angle = anim*0.25;
  float dist = -2.0;
  camera(rot, angle, dist, iResolution.xy, ro, rd);

  gl_FragColor.rgb = cornell(ro, rd);
  gl_FragColor.a = 1.0; 
}
```

You will not be able to rotate around it fully as the back-side of each face will be black (unlit). PRs welcome.

*Note:* You should use `highp` precision in your shaders to support mobile and low-end GPUs.

## Usage

[![NPM](https://nodei.co/npm/glsl-cornell-box.png)](https://www.npmjs.com/package/glsl-cornell-box)

##### `vec3 cornellBox(vec3 ro, vec3 rd)`

Raymarches a cornell box where `ro` is "ray origin" and `rd` is "ray direction." Returns the RGB colors of the scene. The colors are *not* clamped to `0.0 .. 1.0` range; this allows for bloom and other HDR effects.

## License

License Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported License.

[Details](https://creativecommons.org/licenses/by-nc-sa/3.0/)