Add SemiCircle Plugin - reworked. (#1238)

Author: kuaka

examples/Plugins.ipynb

@@ -29,6 +29,7 @@
 from folium.plugins.polyline_text_path import PolyLineTextPath
 from folium.plugins.scroll_zoom_toggler import ScrollZoomToggler
 from folium.plugins.search import Search
+from folium.plugins.semicircle import SemiCircle
 from folium.plugins.terminator import Terminator
 from folium.plugins.time_slider_choropleth import TimeSliderChoropleth
 from folium.plugins.timestamped_geo_json import TimestampedGeoJson
@@ -56,6 +57,7 @@
     'PolyLineOffset',
     'ScrollZoomToggler',
     'Search',
+    'SemiCircle',
     'StripePattern',
     'Terminator',
     'TimeSliderChoropleth',

folium/plugins/__init__.py

@@ -0,0 +1,85 @@
+# -*- coding: utf-8 -*-
+
+from branca.element import Figure, JavascriptLink
+
+from folium.map import Marker
+from folium.utilities import parse_options
+
+from jinja2 import Template
+
+from folium.vector_layers import path_options
+
+_default_js = [
+    ('semicirclejs',
+     'https://cdn.jsdelivr.net/npm/leaflet-semicircle@2.0.4/Semicircle.min.js')
+]
+
+
+class SemiCircle(Marker):
+    """Add a marker in the shape of a semicircle, similar to the Circle class.
+
+    Use (direction and arc) or (start_angle and stop_angle), not both.
+
+    Parameters
+    ----------
+    location: tuple[float, float]
+        Latitude and Longitude pair (Northing, Easting)
+    radius: float
+        Radius of the circle, in meters.
+    direction: int, default None
+        Direction angle in degrees
+    arc: int, default None
+        Arc angle in degrees.
+    start_angle: int, default None
+        Start angle in degrees
+    stop_angle: int, default None
+        Stop angle in degrees.
+    popup: str or folium.Popup, optional
+        Input text or visualization for object displayed when clicking.
+    tooltip: str or folium.Tooltip, optional
+        Display a text when hovering over the object.
+    **kwargs
+        For additional arguments see :func:`folium.vector_layers.path_options`
+
+    Uses Leaflet plugin https://github.com/jieter/Leaflet-semicircle
+
+    """
+    _template = Template(u"""
+        {% macro script(this, kwargs) %}
+            var {{ this.get_name() }} = L.semiCircle(
+                {{ this.location|tojson }},
+                {{ this.options|tojson }}
+                )
+                {%- if this.direction %}
+                    .setDirection({{ this.direction[0] }}, {{ this.direction[1] }})
+                {%- endif %}
+                .addTo({{ this._parent.get_name() }});
+        {% endmacro %}
+        """)
+
+    def __init__(self, location, radius,
+                 direction=None, arc=None,
+                 start_angle=None, stop_angle=None,
+                 popup=None, tooltip=None, **kwargs):
+        super(SemiCircle, self).__init__(location, popup=popup, tooltip=tooltip)
+        self._name = 'SemiCircle'
+        self.direction = (direction, arc) if direction is not None and arc is not None else None
+        self.options = path_options(line=False, radius=radius, **kwargs)
+        self.options.update(parse_options(
+            start_angle=start_angle,
+            stop_angle=stop_angle,
+        ))
+
+        if not ((direction is None and arc is None) and (start_angle is not None and stop_angle is not None)
+                or (direction is not None and arc is not None) and (start_angle is None and stop_angle is None)):
+            raise ValueError("Invalid arguments. Either provide direction and arc OR start_angle and stop_angle")
+
+    def render(self, **kwargs):
+        super(SemiCircle, self).render(**kwargs)
+
+        figure = self.get_root()
+        assert isinstance(figure, Figure), ('You cannot render this Element '
+                                            'if it is not in a Figure.')
+
+        for name, url in _default_js:
+            figure.header.add_child(JavascriptLink(url), name=name)

folium/plugins/semicircle.py

@@ -0,0 +1,70 @@
+# -*- coding: utf-8 -*-
+
+"""
+Test SemiCircle
+---------------
+
+"""
+
+import folium
+from folium import plugins
+from folium.utilities import normalize
+
+from jinja2 import Template
+
+
+def test_semicircle():
+    m = folium.Map([30., 0.], zoom_start=3)
+    sc1 = plugins.SemiCircle(
+        (34, -43),
+        radius=400000,
+        arc=300,
+        direction=20,
+        color='red',
+        fill_color='red',
+        opacity=0,
+        popup='Direction - 20 degrees, arc 300 degrees'
+    )
+    sc2 = plugins.SemiCircle(
+        (46, -30),
+        radius=400000,
+        start_angle=10,
+        stop_angle=50,
+        color='red',
+        fill_color='red',
+        opacity=0,
+        popup='Start angle - 10 degrees, Stop angle - 50 degrees'
+    )
+
+    m.add_child(sc1)
+    m.add_child(sc2)
+    m._repr_html_()
+
+    out = normalize(m._parent.render())
+
+    # We verify that the script import is present.
+    script = '<script src="https://cdn.jsdelivr.net/npm/leaflet-semicircle@2.0.4/Semicircle.min.js"></script>'  # noqa
+    assert script in out
+
+    # We verify that the script part is correct.
+    tmpl_sc1 = Template(u"""
+        var {{ this.get_name() }} = L.semiCircle(
+        {{ this.location|tojson }},
+        {{ this.options | tojson }}
+        )
+            .setDirection{{ this.direction }}
+        .addTo({{ this._parent.get_name() }});
+    """)
+
+    tmpl_sc2 = Template(u"""
+        var {{ this.get_name() }} = L.semiCircle(
+        {{ this.location|tojson }},
+        {{ this.options | tojson }}
+        )
+        .addTo({{ this._parent.get_name() }});
+    """)
+    assert normalize(tmpl_sc1.render(this=sc1)) in out
+    assert normalize(tmpl_sc2.render(this=sc2)) in out
+
+    bounds = m.get_bounds()
+    assert bounds == [[34, -43], [46, -30]], bounds