docs: private boolean isSpatialMaxima(float[][] hmap, int x, int y) {
  		int n = 8;
  		int[] dx = new int[] { -1, 0, 1, 1, 1, 0, -1, -1 };
  		int[] dy = new int[] { -1, -1, -1, 0, 1, 1, 1, 0 };
  		double w = hmap[x][y];
  		for (int i = 0; i < n; i++) {
  			double wk = hmap[x + dx[i]][y + dy[i]];
  			if (wk >= w)
  				return false;
  		}
  		return true;
  	}