1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
|
from __future__ import unicode_literals
import logging
from django.conf import settings
from django.contrib.gis import gdal
from django.contrib.gis.geos import GEOSGeometry, GEOSException
from django.forms.widgets import Widget
from django.template import loader
from django.utils import six
from django.utils import translation
logger = logging.getLogger('django.contrib.gis')
class BaseGeometryWidget(Widget):
"""
The base class for rich geometry widgets.
Renders a map using the WKT of the geometry.
"""
geom_type = 'GEOMETRY'
map_srid = 4326
map_width = 600
map_height = 400
display_raw = False
supports_3d = False
template_name = '' # set on subclasses
def __init__(self, attrs=None):
self.attrs = {}
for key in ('geom_type', 'map_srid', 'map_width', 'map_height', 'display_raw'):
self.attrs[key] = getattr(self, key)
if attrs:
self.attrs.update(attrs)
def serialize(self, value):
return value.wkt if value else ''
def deserialize(self, value):
try:
return GEOSGeometry(value, self.map_srid)
except (GEOSException, ValueError) as err:
logger.error(
"Error creating geometry from value '%s' (%s)" % (
value, err)
)
return None
def render(self, name, value, attrs=None):
# If a string reaches here (via a validation error on another
# field) then just reconstruct the Geometry.
if isinstance(value, six.string_types):
value = self.deserialize(value)
if value:
# Check that srid of value and map match
if value.srid != self.map_srid:
try:
ogr = value.ogr
ogr.transform(self.map_srid)
value = ogr
except gdal.OGRException as err:
logger.error(
"Error transforming geometry from srid '%s' to srid '%s' (%s)" % (
value.srid, self.map_srid, err)
)
context = self.build_attrs(attrs,
name=name,
module='geodjango_%s' % name.replace('-','_'), # JS-safe
serialized=self.serialize(value),
geom_type=gdal.OGRGeomType(self.attrs['geom_type']),
STATIC_URL=settings.STATIC_URL,
LANGUAGE_BIDI=translation.get_language_bidi(),
)
return loader.render_to_string(self.template_name, context)
class OpenLayersWidget(BaseGeometryWidget):
template_name = 'gis/openlayers.html'
class Media:
js = (
'http://openlayers.org/api/2.11/OpenLayers.js',
'gis/js/OLMapWidget.js',
)
class OSMWidget(BaseGeometryWidget):
"""
An OpenLayers/OpenStreetMap-based widget.
"""
template_name = 'gis/openlayers-osm.html'
default_lon = 5
default_lat = 47
class Media:
js = (
'http://openlayers.org/api/2.11/OpenLayers.js',
'http://www.openstreetmap.org/openlayers/OpenStreetMap.js',
'gis/js/OLMapWidget.js',
)
@property
def map_srid(self):
# Use the official spherical mercator projection SRID on versions
# of GDAL that support it; otherwise, fallback to 900913.
if gdal.HAS_GDAL and gdal.GDAL_VERSION >= (1, 7):
return 3857
else:
return 900913
def render(self, name, value, attrs=None):
default_attrs = {
'default_lon': self.default_lon,
'default_lat': self.default_lat,
}
if attrs:
default_attrs.update(attrs)
return super(OSMWidget, self).render(name, value, default_attrs)
|
