code: function subdivide( detail ) {
  
  		var a = new Vector3();
  		var b = new Vector3();
  		var c = new Vector3();
  
  		// iterate over all faces and apply a subdivison with the given detail value
  
  		for ( var i = 0; i < indices.length; i += 3 ) {
  
  			// get the vertices of the face
  
  			getVertexByIndex( indices[ i + 0 ], a );
  			getVertexByIndex( indices[ i + 1 ], b );
  			getVertexByIndex( indices[ i + 2 ], c );
  
  			// perform subdivision
  
  			subdivideFace( a, b, c, detail );
  
  		}
  
  	}
docs: helper functions