{
  "cells": [
    {
      "cell_type": "markdown",
      "metadata": {},
      "source": [
        "\n# Custom hillshading in a 3D surface plot\n\nDemonstrates using custom hillshading in a 3D surface plot.\n"
      ]
    },
    {
      "cell_type": "code",
      "execution_count": null,
      "metadata": {
        "collapsed": false
      },
      "outputs": [],
      "source": [
        "import matplotlib.pyplot as plt\nimport numpy as np\n\nfrom matplotlib import cbook\nfrom matplotlib.colors import LightSource\n\n# Load and format data\ndem = cbook.get_sample_data('jacksboro_fault_dem.npz')\nz = dem['elevation']\nnrows, ncols = z.shape\nx = np.linspace(dem['xmin'], dem['xmax'], ncols)\ny = np.linspace(dem['ymin'], dem['ymax'], nrows)\nx, y = np.meshgrid(x, y)\n\nregion = np.s_[5:50, 5:50]\nx, y, z = x[region], y[region], z[region]\n\n# Set up plot\nfig, ax = plt.subplots(subplot_kw=dict(projection='3d'))\n\nls = LightSource(270, 45)\n# To use a custom hillshading mode, override the built-in shading and pass\n# in the rgb colors of the shaded surface calculated from \"shade\".\nrgb = ls.shade(z, cmap=plt.colormaps[\"gist_earth\"], vert_exag=0.1, blend_mode='soft')\nsurf = ax.plot_surface(x, y, z, rstride=1, cstride=1, facecolors=rgb,\n                       linewidth=0, antialiased=False, shade=False)\n\nplt.show()"
      ]
    },
    {
      "cell_type": "markdown",
      "metadata": {},
      "source": [
        ".. tags::\n   plot-type: 3D,\n   level: intermediate,\n   domain: cartography\n\n"
      ]
    }
  ],
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      "display_name": "Python 3",
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      "file_extension": ".py",
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