Writing README.

README.md

@@ -1,2 +1,33 @@
-# elite-matrix
-A small library for working with the Elite Dangerous color matrix.
+# Elite Matrix
+A (very) small library for working with the Elite Dangerous color matrix in javascript. Types
+included!
+
+Adapted from [EDScout's color adjuster][ed-scout].
+
+# Usage
+`npm i elite-matrix`
+
+The input matrix is stored in an EliteMatrix object, and must be passed in as three arrays, one for
+each line in the matrix, each containing three numbers.
+
+A GraphicsConfiguration.xml that looks like this:
+```xml
+<MatrixRed>		1, 0, 0 </MatrixRed>
+<MatrixGreen>	0, 1, 0 </MatrixGreen>
+<MatrixBlue>	0, 0, 1 </MatrixBlue>
+```
+
+Would need to be translated into this and passed to EliteMatrix:
+```javascript
+import { EliteMatrix } from 'elite-matrix';
+
+const matrixRed = [1, 0, 0];
+const matrixGreen = [0, 1, 0];
+const matrixBlue = [0, 0, 1];
+const matrix = new EliteMatrix(matrixRed, matrixGreen, matrixBlue);
+```
+
+From there you can use the `EliteMatrix` object to apply color filters. `filterColor` accepts either
+a string hex color, or an RGB array. It will return in a matching format.
+
+[ed-scout]: https://github.com/joncage/ed-scout/blob/master/EDScoutWebUI/HudColourAdjuster.py#L37