old_contents: 
  import { Color }  from '../../../../three.js/src/Three.js';
  import { Colours } from './Colours.js';
  
  // define colors to share THREE.Color objects
  
  function createCache ( colours ) {
  
  	var cache = [];
  
  	for ( var i = 0, l = colours.length; i < l; i++ ) {
  
  		cache[i] = new Color( colours[i] );
  
  	}
  
  	return cache;
  
  }
  
  export var ColourCache = {
  	inclination: createCache( Colours.inclinationColours ),
  	terrain:     createCache( Colours.terrainColours ),
  	gradient:    createCache( Colours.gradientColours ),
  	survey:      createCache( Colours.surveyColours ),
  	red:         new Color( 0xff0000 ),
  	white:       new Color( 0xffffff ),
  	grey:        new Color( 0x444444 )
  };
  
new_contents: 
  import { Color }  from '../../../../three.js/src/Three.js';
  import { Colours } from './Colours.js';
  
  // define colors to share THREE.Color objects
  
  function createCache ( colours ) {
  
  	var cache = [];
  
  	for ( var i = 0, l = colours.length; i < l; i++ ) {
  
  		cache[i] = new Color( colours[i] );
  
  	}
  
  	return cache;
  
  }
  
  export var ColourCache = {
  	inclination: createCache( Colours.inclinationColours ),
  	terrain:     createCache( Colours.terrainColours ),
  	gradient:    createCache( Colours.gradientColours ),
  	survey:      createCache( Colours.surveyColours ),
  	red:         new Color( 0xff0000 ),
  	yellow:	     new Color( 0xffff00 ),
  	white:       new Color( 0xffffff ),
  	grey:        new Color( 0x444444 )
  };
  
subject: add new colour