.. _example_webmaps:

===================================
WebMap services and layer-switching
===================================

- add WebMap services using ``m.add_wms`` and ``m.add_wmts``
- compare different data-layers and WebMap services using ``m.cb.click.peek_layer`` and ``m.cb.keypress.switch_layer``


.. image:: /_static/example_images/example_webmaps.gif
    :width: 75%
    :align: center

.. code-block:: python

    # EOmaps example: WebMap services and layer-switching

    from eomaps import Maps
    import numpy as np
    import pandas as pd

    # ------ create some data --------
    lon, lat = np.meshgrid(np.linspace(-50, 50, 150), np.linspace(30, 60, 150))
    data = pd.DataFrame(
        dict(lon=lon.flat, lat=lat.flat, data=np.sqrt(lon**2 + lat**2).flat)
    )
    # --------------------------------

    m = Maps(Maps.CRS.GOOGLE_MERCATOR, layer="S1GBM_vv", figsize=(9, 4))
    # set the crs to GOOGLE_MERCATOR to avoid reprojecting the WebMap data
    # (makes it a lot faster and it will also look much nicer!)

    # add S1GBM WebMap to the layer of this Maps-object
    m.add_wms.S1GBM.add_layer.vv()

    # add OpenStreetMap on the currently invisible layer (OSM)
    m.add_wms.OpenStreetMap.add_layer.default(layer="OSM")

    # create a new layer named "data" and plot some data
    m2 = m.new_layer(layer="data")
    m2.set_data(data=data.sample(5000), x="lon", y="lat", crs=4326)
    m2.set_shape.geod_circles(radius=20000)
    m2.plot_map()


    # -------- CALLBACKS ----------
    # (use m.all to execute independent of the visible layer)
    # on a left-click, show layers ("data", "OSM") in a rectangle
    m.all.cb.click.attach.peek_layer(layer="OSM|data", how=0.2)

    # on a right-click, "swipe" the layers ("S1GBM_vv" and "data") from the left
    m.all.cb.click.attach.peek_layer(
        layer="S1GBM_vv|data",
        how="left",
        button=3,
    )

    # switch between the layers by pressing the keys 0, 1 and 2
    m.all.cb.keypress.attach.switch_layer(layer="S1GBM_vv", key="0")
    m.all.cb.keypress.attach.switch_layer(layer="OSM", key="1")
    m.all.cb.keypress.attach.switch_layer(layer="data", key="2")

    # add a pick callback that is only executed if the "data" layer is visible
    m2.cb.pick.attach.annotate(zorder=100)  # use a high zorder to put it on top

    # ------ UTILITY WIDGETS --------
    # add a clickable widget to switch between layers
    m.util.layer_selector(
        loc="upper left",
        ncol=3,
        bbox_to_anchor=(0.01, 0.99),
        layers=["OSM", "S1GBM_vv", "data"],
    )
    # add a slider to switch between layers
    s = m.util.layer_slider(
        pos=(0.5, 0.93, 0.38, 0.025),
        color="r",
        handle_style=dict(facecolor="r"),
        txt_patch_props=dict(fc="w", ec="none", alpha=0.75, boxstyle="round, pad=.25"),
    )

    # explicitly set the layers you want to use in the slider
    # (Note: you can also use combinations of multiple existing layers!)
    s.set_layers(["OSM", "S1GBM_vv", "data", "OSM|data{0.5}"])

    # ------------------------------

    m.add_logo()

    m.apply_layout(
        {
            "figsize": [9.0, 4.0],
            "0_map": [0.00625, 0.01038, 0.9875, 0.97924],
            "1_slider": [0.45, 0.93, 0.38, 0.025],
            "2_logo": [0.865, 0.02812, 0.12, 0.11138],
        }
    )

    # fetch all layers before startup so that they are already cached
    m.fetch_layers()
    m.show()