## HelperFunctions

### Methods

#### static addMouseScrollEventListener(query, func)
`modules/other/helperFunctions.js`, `line 12`

  add a cross browser event listener on a mouse scroll

  ##### Parameters:

  Name | Type | Description
  --- | --- | ---
  `query` | string | DOM query of the element that the listener will be added to
  `func` | function | Function that will be called when the event occurs. The function takes as a parameter an event object.

#### static getJSONString(data, prettyopt, dataUriopt) → {string}
`modules/other/helperFunctions.js`, `line 58`

  convert a data object to JSON string or to a data URI containing a JSON string

  ##### Parameters:

  Name | Type | Attributes | Default | Description
  --- | --- | --- | --- | ---
  `data` | Object |  |  | object that will be serialized into a JSON string
  `pretty` | Boolean | <optional> | false | if `true`, the code will be proprerly indented, else a more compact syntax will be used
  `dataUri` | Boolean | <optional> | false | return dataUri containing the JSON string instead of the pure JSON string

  ##### Returns:

  string

#### static manhattanDistance(a, b) → {number}
`modules/other/helperFunctions.js`, `line 76`

  returns the Manhattan distance between the points a and b

  ##### Parameters:

  Name | Type | Description
  --- | --- | ---
  `a` | Object | object containing numeric attributes `x` and `y`
  `b` | Object | object containing numeric attributes `x` and `y`

  ##### Returns:

  number