code: function( src, pixels, offset ){
              if( typeof offset !== 'number'){
                  offset = 0;
              } else if ( offset < 0 ){
                  throw new Error("offset into target pixel array is negative");
              }
              pixels = pixels || new Array(src.length);
              for(var i=0, l=src.length; i<l; i++){
                  pixels[offset++] = this.getToneFor(src[i]).toARGB();
              }
              return pixels;
          }
docs: Applies the tonemap to all elements in the given source array of
  values and places the resulting ARGB color in the corresponding
  index of the target pixel buffer. If the target buffer is null, a new one
  will be created automatically.
  
  @param {Array<Number>}src source array of values to be tone mapped
  @param {Array<Number>}pixels target pixel buffer
  @param {Number} [offset] optionally provide an index-offset to start
  at in the destination pixels array
  @return pixel array