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[rbdr/tomato-sauce] / README.md

## Tomato Sauce

Draw stuff via telnet

## How to run

You will need [Node.js][node] installed, at least version 8. Install
dependencies by running `npm install` from the root of the project
and start the server by running `npm start`. It will listen on port 9999
by default.

## Configuration variables

Tomato Sauce can be configured using env variables:

* `TOMATO_SAUCE_PORT`: The port to listen on. Defauts to 9999.
* `TOMATO_SAUCE_FREQUENCY`: How often it will send a screen in
  miliseconds. Defaults to 333.
* `TOMATO_SAUCE_MODULATION`: How much the modulation counter will
  increase per round. Defaults to 5.
* `TOMATO_SAUCE_SCREEN_PATH`: Path from which we will load screens. It
  defaults to `{project_root}/lib/screens`
* `TOMATO_SAUCE_RENDERER_PATH`: Path from which we will load renderers. It
  defaults to `{project_root}/lib/renderers`

## Make your own screens

A screen is a function that will receive a modulation value from 0-255,
the width of the viewport, the height of the viewport, and a renderer
function, and it returns a string that consists of the commands that
will be sent to the socket.

  * `IScreen(modulation <int>, width <int>, height <int>, renderer
    <IRenderer>) -> payload <string>`

It should output the required commands that telnet needs to move the
cursor and draw. For convenience, a renderer function is passed so
calculating color should not be a part of the screen, just moving the
cursor around and calling specific colors.

## Make your own renderers

The included renderers are wrappers to some common ways of obtaining
colors in the terminal: ANSI, 256 colors, 24-bit colors, and a fake
color string that uses incorrect color strings to generate random
variations.

You can build your own renderer by building a function that receives a
red, green, and blue component from 0 to 255 and returns the escape
codes to generate the color.

  * `IRenderer(red <int>, green <int>, blue <int>) ->
    colorString <string>`

## Using as a library

The binary just serves as a wrapper to read configuration, and as a
bridge to the console. It consumes `lib/tomato_sauce`. All configuration
is optional, and should be passed as an object on instantiation. The
instance is an event emitter that will emit a `listening` event with
the server data, and an `error` event in case something goes wrong.

```
const TomatoSauce = require('tomato-sauce');

const tomatoSauce = new TomatoSauce(config);

tomatoSauce.on('listening', () => {

  const address = event.data.server.address();
  console.log(`Tomato Sauce listening on: ${address.address}:${address.port}`);
});

tomatoSauce.on('error', (error) => {

  console.error(error);
});

tomatoSauce.run();
```

### Configuration Values

The config object should be a simple object with these keys (All are
optional.)

  * `port`: The port to listen on (Defaults to 9999)
  * `frequency`: How often we'll send a new frame in milliseconds
    (Defaults to 333)
  * `modulation`: How fast the modulation counter will be increased
    (Defaults to 5)
  * `screens`: An array containing the screen functions (Defaults to [])
  * `renderers`: An array containing the renderer functions (Defaults to [])

[node]: https://nodejs.org/en/