Shaders.create.md

# GL.Shaders.create

`GL.Shaders.create(spec)` allows to create shaders that can be used later in *GL.View* component.


**Example usage:**

```js
var shaders = GL.Shaders.create({
  myEffect: {
    frag: `
void main () {
  gl_FragColor = vec4(1.0, 0.0, 0.0, 1.0); // red
}
    `
  },
  ...
})

// Use it later:
<GL.View shader={shaders.myEffect} ... />
```

There are two kinds of OpenGL Shaders: vertex and fragment shaders.
The vertex shader iterates over polygons and computes a position, the fragment shaders iterates over pixels and computes a color.

In current version of `gl-react-native`, the vertex shader is implemented for you
and you only have to implement the fragment shader.

> This documentation assumes you know the basics of GLSL, the OpenGL Shading Language, if not, feel free to learn [shader-school](https://www.npmjs.com/package/shader-school), read the [specification](https://www.opengl.org/documentation/glsl/) or learn from the examples.


`GL.Shaders.create` is inspired from ReactNative's `StyleSheet.create`: it creates an object with key-value and will returns an object with the same keys and where the values can be used in the Virtual DOM.

The value of each Shader is an object with a `frag` field: the fragment GLSL code.