code: protected CompositedMirage createCompositedMirage (int index)
      {
          if (_sources.length == 1 && _sources[0].frames instanceof TileSetFrameImage) {
              TileSetFrameImage frames = (TileSetFrameImage)_sources[0].frames;
              Rectangle tbounds = new Rectangle();
              frames.getTrimmedBounds(_orient, index, tbounds);
              int x = frames.getXOrigin(_orient, index) - tbounds.x;
              int y = frames.getYOrigin(_orient, index) - tbounds.y;
              return new SubmirageForwarder(frames.getTileMirage(_orient, index), x, y);
          }
          return new CompositedVolatileMirage(index);
      }
docs: Creates a composited image for the specified frame.