# Contribution guidelines

## Getting up and running with build tools

We use gulp for processing CSS and HTML for the website, and Rollup.js for bundling Color.js.

1. [Install npm](https://www.npmjs.com/get-npm) if you don't already have it
2. `cd` to the project directory and run `npm install` to install local modules
3. Done! Now run `npx gulp` to build.

Run `npx gulp watch` before you start working on the website to have gulp run automatically as you edit files.

Or, for individual tasks:

- `gulp md` to convert Markdown files to HTML pages
- `gulp css` to process PostCSS files (`*.src.css` in our repo)
- `gulp bundle` to create Color.js bundles in `dist/`

## Commit messages

- If working on a color space, please prefix your commit with `[spaces/SPACE_ID]`
- If working on a demo app, please prefix your commit with `[apps/APP_ID]`
- If working on a module other than color.js, please prefix your commit with `[modulename]` e.g. `[interpolation]`

## Code style

Please install an ESLint plugin for your editor. There is an `.eslintrc.json` file in the repo which encodes most of the coding style of the project.

Here are a few other guideliines that cannot be enforced via ESLint:

- When you define a function, use a space between the opening paren and its name. That way we can search for "functionName (" and find its definition immediately, instead of having to wade through calls to the function.
- Prefer single-word names over multi-word names. 3+ word names are especially frowned upon.
- camelCase over underscore_case, with few exceptions.
- Don't be afraid of unicode characters when appropriate, except on user-facing names. E.g. use ε over epsilon internally, but not ΔΕ over deltaE in the public-facing method name.