cutline_creation.ipynb

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    "from typing import Literal, Callable\n",
    "import shapely.geometry\n",
    "import geopandas as gpd\n",
    "import numpy as np\n",
    "\n",
    "maxc = 20037508.342789244\n",
    "sidelength: Callable[[int], float] = lambda z: 2 * maxc / (2**z)\n",
    "\n",
    "def get_ulx_uly_lrx_lry(\n",
    "    z: int, x: int, y: int\n",
    ") -> tuple[\n",
    "    float, float, float, float\n",
    "]:  # upper left x, upper left y, lower right x, lower right y\n",
    "\n",
    "    ulx = -maxc + sidelength(z) * x\n",
    "    uly = maxc - sidelength(z) * y\n",
    "\n",
    "    lrx = -maxc + sidelength(z) * (x + 1)\n",
    "    lry = maxc - sidelength(z) * (y + 1)\n",
    "\n",
    "    return ulx, uly, lrx, lry\n",
    "\n",
    "z,x,y = 11,1085,595\n",
    "\n",
    "pixelcount = 40\n",
    "ulx, uly, lrx, lry = get_ulx_uly_lrx_lry(z,x,y)\n",
    "\n",
    "s = shapely.geometry.box(ulx, uly, lrx, lry)\n",
    "gpd.GeoSeries(s).set_crs(3857).to_file(\"tile.geojson\")\n",
    "\n",
    "s = sidelength(z) / pixelcount\n",
    "\n",
    "pixels : list[shapely.geometry.Polygon] = []\n",
    "\n",
    "for col_index in range(pixelcount):\n",
    "    for row_index in range(pixelcount):\n",
    "        corners: list[np.ndarray[tuple[Literal[2]], np.dtype[np.float64]]] = []\n",
    "        for each in [[1, 1], [1, -1], [-1, -1], [-1, 1], [1, 1]]:\n",
    "            tc = np.array([ulx + s * col_index + s/2, uly - s * row_index - s / 2])\n",
    "            v = 0.5 * np.array([each]) * np.array([s, s])\n",
    "            [corner] = tc + v\n",
    "            corners.append(corner)\n",
    "        p = shapely.geometry.Polygon(corners)\n",
    "        pixels.append(p)\n",
    "\n",
    "gpd.GeoSeries(pixels).set_crs(3857).to_file(\"pixels.gpkg\")"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 2,
   "id": "226ba3e0",
   "metadata": {},
   "outputs": [],
   "source": [
    "!open ."
   ]
  }
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