.. _sphx_glr_gallery_eyja_volcano.py:


Map tile acquisition
--------------------

Demonstrates cartopy's ability to draw map tiles which are downloaded on
demand from the Stamen tile server. Internally these tiles are then combined
into a single image and displayed in the cartopy GeoAxes.

Grabbing the map tiles
======================





.. image:: /gallery/images/sphx_glr_eyja_volcano_001.png
    :align: center





.. code-block:: python


    import matplotlib.pyplot as plt
    from matplotlib.transforms import offset_copy

    import cartopy.crs as ccrs
    import cartopy.io.img_tiles as cimgt


    def main():
        # Create a Stamen Terrain instance.
        stamen_terrain = cimgt.StamenTerrain()

        fig = plt.figure()

        # Create a GeoAxes in the tile's projection.
        ax = fig.add_subplot(1, 1, 1, projection=stamen_terrain.crs)

        # Limit the extent of the map to a small longitude/latitude range.
        ax.set_extent([-22, -15, 63, 65], crs=ccrs.Geodetic())

        # Add the Stamen data at zoom level 8.
        ax.add_image(stamen_terrain, 8)

        # Add a marker for the Eyjafjallajökull volcano.
        ax.plot(-19.613333, 63.62, marker='o', color='red', markersize=12,
                alpha=0.7, transform=ccrs.Geodetic())

        # Use the cartopy interface to create a matplotlib transform object
        # for the Geodetic coordinate system. We will use this along with
        # matplotlib's offset_copy function to define a coordinate system which
        # translates the text by 25 pixels to the left.
        geodetic_transform = ccrs.Geodetic()._as_mpl_transform(ax)
        text_transform = offset_copy(geodetic_transform, units='dots', x=-25)

        # Add text 25 pixels to the left of the volcano.
        ax.text(-19.613333, 63.62, u'Eyjafjallajökull',
                verticalalignment='center', horizontalalignment='right',
                transform=text_transform,
                bbox=dict(facecolor='sandybrown', alpha=0.5, boxstyle='round'))
        plt.show()


    if __name__ == '__main__':
        main()

**Total running time of the script:** ( 0 minutes  0.045 seconds)



.. container:: sphx-glr-footer


  .. container:: sphx-glr-download

     :download:`Download Python source code: eyja_volcano.py <eyja_volcano.py>`



  .. container:: sphx-glr-download

     :download:`Download Jupyter notebook: eyja_volcano.ipynb <eyja_volcano.ipynb>`

.. rst-class:: sphx-glr-signature

    `Generated by Sphinx-Gallery <https://sphinx-gallery.readthedocs.io>`_