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README.md

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 # coloralgorithm
-Javacript function to produce color sets
+
+A JavaScript function for producing color sets. Used to build Lyft's color system (Spectrum) and power [ColorBox](https://www.colorbox.io/).
+
+## Background
+
+- [Re-Approaching Color by Lyft Design](https://design.lyft.com/re-approaching-color-9e604ba22c88)
+- [Designing a Comprehensive Color System by Linda Dong](https://www.rethinkhq.com/videos/designing-a-comprehensive-color-system-for-lyft)
+
+## Usage
+
+The function takes in a JavaScript object with a `specs` key that describes the properties of the desired color palette:
+
+```javascript
+import generate from "./src/generate";
+
+const input = {
+  specs: {
+    // Number of colors
+    steps: 11,
+    // Hue Start Value (0 - 359)
+    hue_start: 315,
+    // Hue End Value (0 - 359)
+    hue_end: 293,
+    // Hue Curve (See Curves Section)
+    hue_curve: "easeInQuad",
+    // Saturation Start Value (0 - 100)
+    sat_start: 4,
+    // Saturation End Value (0 - 100)
+    sat_end: 90,
+    // Saturation Curve (See Curves Section)
+    sat_curve: "easeOutQuad",
+    // Saturation Rate (0 - 200)
+    sat_rate: 130,
+    // Luminosity Start Value (0 - 100)
+    lum_start: 100,
+    // Luminosity End Value (0 - 100)
+    lum_end: 53,
+    // Luminosity Curve (See Curves Section)
+    lum_curve: "easeOutQuad",
+    // Modifier Scale
+    // Every generated color gets a modifier (label) that
+    // indicates its lightness. A value of 10 results in
+    // two-digit modifiers. The lightest color will be 0 (e.g. Red 0)
+    // and the darkest color will be 100 (e.g. Red 100), given
+    // that you generate 11 colors
+    modifier: 10
+  }
+};
+
+const palette = generate(input);
+```
+
+Contrary to ColorBox, this version of the algorithm _does not_ support a lock color.
+
+## Example Output
+
+The function returns the generated palette as an array of color objects:
+
+```javascript
+[
+  {
+    contrastBlack: "19.32",
+    contrastWhite: "1.09",
+    displayColor: "black",
+    hex: "#fff2fc",
+    hsl: [315, 1, 0.974],
+    hsv: [314.99999999999994, 0.052000000000000074, 1],
+    hue: 314.99999999999994,
+    hueRange: [315, 293],
+    label: 0,
+    lum: 1,
+    rgb: [255, 242, 252],
+    sat: 0.052000000000000074,
+    steps: 11
+  },
+  ...
+];
+```
+
+## Curves
+
+Hue, Saturation, and Luminosity all allow you to specify a curve. The following curves are supported:
+
+- _easeInQuad_ (Quad - EaseIn)
+- _easeOutQuad_ (Quad - EaseOut)
+- _easeInOutQuad_ (Quad - EaseInOut)
+- _easeInQuart_ (Quart - EaseIn)
+- _easeOutQuart_ (Quart - EaseOut)
+- _easeInOutQuart_ (Quart - EaseInOut)
+- _easeInSine_ (Sine - EaseIn)
+- _easeOutSine_ (Sine - EaseOut)
+- _easeInOutSine_ (Sine - EaseInOut)
+- _easeInCubic_ (Cubic - EaseIn)
+- _easeOutCubic_ (Cubic - EaseOut)
+- _easeInOutCubic_ (Cubic - EaseInOut)
+- _easeInExpo_ (Expo - EaseIn)
+- _easeOutExpo_ (Expo - EaseOut)
+- _easeInOutExpo_ (Expo - EaseInOut)
+- _easeInQuint_ (Quint - EaseIn)
+- _easeOutQuint_ (Quint - EaseOut)
+- _easeInOutQuint_ (Quint - EaseInOut)
+- _easeInCirc_ (Circ - EaseIn)
+- _easeOutCirc_ (Circ - EaseOut)
+- _easeInOutCirc_ (Circ - EaseInOut)
+- _easeInBack_ (Back - EaseIn)
+- _easeOutBack_ (Back - EaseOut)
+- _easeInOutBack_ (Back - EaseInOut)
+- _linear_ (linear)