code: @Override
      public void prepare()
      {
          if (surface == null)
          {
              throw new LionEngineException(ERROR_SURFACE);
          }
          final Graphic g = surface.createGraphic();
          final int v = map.getInTileHeight();
          final int h = map.getInTileWidth();
  
          for (int ty = 0; ty < v; ty++)
          {
              for (int tx = 0; tx < h; tx++)
              {
                  final Tile tile = map.getTile(tx, ty);
                  final ColorRgba color = getTileColor(tile);
                  if (!NO_TILE.equals(color))
                  {
                      g.setColor(color);
                      g.drawRect(tx, v - ty - 1, 1, 1, true);
                  }
              }
          }
          g.dispose();
      }
docs: Fill minimap surface with tile color configuration.
  
  @throws LionEngineException If surface has not been loaded ({@link #load()} may have not been called).