# Welcome!
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`prizm` is a Haskell library for transforming colors. Specifically, providing
functions for transforming between different color spaces (`CIE` and `sRGB`),
interpolating colors and adjusting the tint, shade, hue, or lightness or a
color.

The inspiration for this library came from a desire to blend two colors
represented in the `sRGB` color space. My research about color blending and
color space representation in the computer led me to the conclusion that the
`CIE L*Ch` color space is the most effective for blending because it most
accurately represents how the human eye sees hue and therefore preserves (and
blends) hue the most accurately.

## Colour Module
There is a bit of overlap with the Haskell Colour Module; however, this library
is filling a couple of needs the other doesn't satisfy. Primarily
transformations and color mutations in the `CIE L*Ch` space.

## Supported Algorithms
- `sRGB     <-> CIE XYZ `
- `CIE XYZ  <-> CIE L*ab`
- `CIE L*ab <-> CIE L*Ch`

## Supported Functions
- Color interpolation
- Tinting / Darkening
- Lightness
- Hue
- Chroma/Saturation

All of these functions operate on color within the `CIE L*Ch`
representation. The percentage values may range between -100 and 100.

- [General Color Formulas, Data, and Algorithms](http://www.brucelindbloom.com/index.html?Info.html)
- [CIE Conversion Mathematics](http://rip94550.wordpress.com/2011/07/04/color-cielab-and-tristimulus-xyz/)
- [Conversion Algorithm Sources](http://www.easyrgb.com/index.php?X=MATH&H=01)
- [Good list of useful color manipulation formulas](https://github.com/mikeemoo/ColorJizz-PHP/blob/master/src/MischiefCollective/ColorJizz/ColorJizz.php)