Merge pull request #424 from sgvandijk/feature/leaflet-global-switches

Leaflet global switches

Author: ocefpaf

folium/folium.py

@@ -77,6 +77,17 @@ class Map(LegacyMap):
         (going from bottom to top).
     control_scale : bool, default False
         Whether to add a control scale on the map.
+    prefer_canvas : bool, default False
+        Forces Leaflet to use the Canvas back-end (if available) for
+        vector layers instead of SVG. This can increase performance
+        considerably in some cases (e.g. many thousands of circle
+        markers on the map).
+    no_touch : bool, default False
+        Forces Leaflet to not use touch events even if it detects them.
+    disable_3d : bool, default False
+        Forces Leaflet to not use hardware-accelerated CSS 3D
+        transforms for positioning (which may cause glitches in some
+        rare environments) even if they're supported.
 
     Returns
     -------

folium/map.py

@@ -118,6 +118,17 @@ class LegacyMap(MacroElement):
         (going from bottom to top).
     control_scale : bool, default False
         Whether to add a control scale on the map.
+    prefer_canvas : bool, default False
+        Forces Leaflet to use the Canvas back-end (if available) for
+        vector layers instead of SVG. This can increase performance
+        considerably in some cases (e.g. many thousands of circle
+        markers on the map).
+    no_touch : bool, default False
+        Forces Leaflet to not use touch events even if it detects them.
+    disable_3d : bool, default False
+        Forces Leaflet to not use hardware-accelerated CSS 3D
+        transforms for positioning (which may cause glitches in some
+        rare environments) even if they're supported.
 
     Returns
     -------
@@ -142,7 +153,8 @@ def __init__(self, location=None, width='100%', height='100%',
                  zoom_start=10, continuous_world=False, world_copy_jump=False,
                  no_wrap=False, attr=None, min_lat=-90, max_lat=90,
                  min_lon=-180, max_lon=180, max_bounds=True,
-                 detect_retina=False, crs='EPSG3857', control_scale=False):
+                 detect_retina=False, crs='EPSG3857', control_scale=False,
+                 prefer_canvas=False, no_touch=False, disable_3d=False):
         super(LegacyMap, self).__init__()
         self._name = 'Map'
         self._env = ENV
@@ -176,6 +188,8 @@ def __init__(self, location=None, width='100%', height='100%',
         self.crs = crs
         self.control_scale = control_scale
 
+        self.global_switches = GlobalSwitches(prefer_canvas, no_touch, disable_3d)
+
         if tiles:
             self.add_tile_layer(
                 tiles=tiles, min_zoom=min_zoom, max_zoom=max_zoom,
@@ -254,6 +268,9 @@ def render(self, **kwargs):
         assert isinstance(figure, Figure), ("You cannot render this Element "
                                             "if it's not in a Figure.")
 
+        # Set global switches
+        figure.header.add_child(self.global_switches, name='global_switches')
+
         # Import Javascripts
         for name, url in _default_js:
             figure.header.add_child(JavascriptLink(url), name=name)
@@ -284,6 +301,24 @@ def render(self, **kwargs):
         super(LegacyMap, self).render(**kwargs)
 
 
+class GlobalSwitches(Element):
+    def __init__(self, prefer_canvas=False, no_touch=False, disable_3d=False):
+        super(GlobalSwitches, self).__init__()
+        self._name = 'GlobalSwitches'
+
+        self.prefer_canvas = prefer_canvas
+        self.no_touch = no_touch
+        self.disable_3d = disable_3d
+
+        self._template = Template(
+            '<script>'
+            'L_PREFER_CANVAS = {% if this.prefer_canvas %}true{% else %}false{% endif %}; '
+            'L_NO_TOUCH = {% if this.no_touch %}true{% else %}false{% endif %}; '
+            'L_DISABLE_3D = {% if this.disable_3d %}true{% else %}false{% endif %};'
+            '</script>'
+        )
+
+
 class Layer(MacroElement):
     """An abstract class for everything that is a Layer on the map.
     It will be used to define whether an object will be included in

folium/templates/fol_template.html

@@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <head>
    <meta http-equiv="content-type" content="text/html; charset=UTF-8" />
-
+   <script>L_PREFER_CANVAS=false; L_NO_TOUCH=false; L_DISABLE_3D=false;</script>
    <script src="https://cdnjs.cloudflare.com/ajax/libs/leaflet/0.7.3/leaflet.js"></script>
    <script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>
    <script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.2.0/js/bootstrap.min.js"></script>

tests/test_folium.py

@@ -80,6 +80,9 @@ def test_init(self):
         assert self.map.width == (900, 'px')
         assert self.map.left == (0, '%')
         assert self.map.top == (0, '%')
+        assert self.map.global_switches.prefer_canvas is False
+        assert self.map.global_switches.no_touch is False
+        assert self.map.global_switches.disable_3d is False
         assert self.map.to_dict() == {
             "name": "Map",
             "id": "00000000000000000000000000000000",
@@ -422,3 +425,24 @@ def test_tile_layer(self):
 
         bounds = self.map.get_bounds()
         assert bounds == [[None, None], [None, None]], bounds
+
+    def test_global_switches(self):
+        mapa = folium.Map(prefer_canvas=True)
+        assert (mapa.global_switches.prefer_canvas is True and
+                mapa.global_switches.no_touch is False and
+                mapa.global_switches.disable_3d is False)
+
+        mapb = folium.Map(no_touch=True)
+        assert (mapb.global_switches.prefer_canvas is False and
+                mapb.global_switches.no_touch is True and
+                mapb.global_switches.disable_3d is False)
+
+        mapc = folium.Map(disable_3d=True)
+        assert (mapc.global_switches.prefer_canvas is False and
+                mapc.global_switches.no_touch is False and
+                mapc.global_switches.disable_3d is True)
+
+        mapd = folium.Map(prefer_canvas=True, no_touch=True, disable_3d=True)
+        assert (mapd.global_switches.prefer_canvas is True and
+                mapd.global_switches.no_touch is True and
+                mapd.global_switches.disable_3d is True)