Integrating with Python

This page gives some examples of integrating mappyfile into Python based work flows.

Displaying Geometry

The examples below recreates the sample images used in the Shapely documentation.

See geometry.py and geometry.map.

mapfile["size"] = [600, 600]

Dilated

def dilation(mapfile):
    line = LineString([(0, 0), (1, 1), (0, 2), (2, 2), (3, 1), (1, 0)])
    ll = mappyfile.find(mapfile["layers"], "name", "line")
    assert ll is not None
    ll["features"][0]["wkt"] = line.wkt

    dilated = line.buffer(0.5, cap_style=3)
    pl = mappyfile.find(mapfile["layers"], "name", "polygon")
    assert pl is not None
    pl["features"][0]["wkt"] = dilated.wkt

    mapfile["extent"] = " ".join(map(str, dilated.buffer(0.8).bounds))
    return dilated

Eroded

def erosion(mapfile, dilated):
    """
    We will continue to work with the modified Mapfile
    If we wanted to start from scratch we could simply reread it
    """
    ll = mappyfile.find(mapfile["layers"], "name", "line")
    assert ll is not None
    ll["status"] = "OFF"

    pl = mappyfile.find(mapfile["layers"], "name", "polygon")
    assert pl is not None

    # make a deep copy of the polygon layer in the Map
    # so any modification are made to this layer only
    pl2 = deepcopy(pl)

    pl2["name"] = "newpolygon"
    mapfile["layers"].append(pl2)

    dilated = dilated.buffer(-0.3)
    pl2["features"][0]["wkt"] = dilated.wkt

    style = pl["classes"][0]["styles"][0]
    style["color"] = "#999999"
    style["outlinecolor"] = "#b2b2b2"

Animated Buffers

See animated_buffer.py and animated_buffer.map.