function _setColourOption (key, val) {
  if (is.object(val) || is.string(val)) {
    const colour = color(val);
    this.options[key] = [
      colour.red(),
      colour.green(),
      colour.blue(),
      Math.round(colour.alpha() * 255)
    ];
  }
}
function _setColourOption (key, val) {
  if (is.object(val) || is.string(val)) {
    const colour = color(val);
    this.options[key] = [
      colour.red(),
      colour.green(),
      colour.blue(),
      Math.round(colour.alpha() * 255)
    ];
  }
}
function _setColourOption ( key , val ) { if ( is . object ( val ) || is . string ( val ) ) { const colour = color ( val ) ; this . options [ key ] = [ colour . red ( ) , colour . green ( ) , colour . blue ( ) , Math . round ( colour . alpha ( ) * 255 ) ] ; } }
Update a colour attribute of the this.options Object.
@private
@param {String} key
@param {String|Object} val
@throws {Error} Invalid key
Update a colour attribute of the this . options Object .
Set colour option