def register_layer(self, layer, defaultstyle, extrastyles=()):
layername = layer.name
#差错机制，检测相关参数是否有效
if not layername:
#ServerConfigurationError为从ogcserver.exceptions中导入的方法，执行内容为空
raise ServerConfigurationError(
'Attempted to register an unnamed layer.')
if not layer.wms_srs and not re.match('^\+init=epsg:\d+$',
layer.srs) and not re.match(
'^\+proj=.*$', layer.srs):
raise ServerConfigurationError(
'Attempted to register a layer without an epsg projection defined.'
)
if defaultstyle not in self.styles.keys() + self.aggregatestyles.keys(
):
raise ServerConfigurationError(
'Attempted to register a layer with an non-existent default style.'
)
layer.wmsdefaultstyle = defaultstyle
# 判断是否为tuple类型，（'a',)为tuple类型，aggregates也为tuple类型
# type(('a',))输出为 tuple
if isinstance(extrastyles, tuple):
#
for stylename in extrastyles:
# 如果stylename类型为str
if type(stylename) == type(''):
if stylename not in self.styles.keys(
) + self.aggregatestyles.keys():
raise ServerConfigurationError(
'Attempted to register a layer with an non-existent extra style.'
)
else:
ServerConfigurationError(
'Attempted to register a layer with an invalid extra style name.'
)
# wmsextrastyles？？？？
layer.wmsextrastyles = extrastyles
else:
raise ServerConfigurationError(
'Layer "%s" was passed an invalid list of extra styles. List must be a tuple of strings.'
% layername)
# 调用common中Projection
layerproj = common.Projection(layer.srs)
env = layer.envelope()
llp = layerproj.inverse(Coord(env.minx, env.miny))
urp = layerproj.inverse(Coord(env.maxx, env.maxy))
if self.latlonbb is None:
self.latlonbb = Envelope(llp, urp)
else:
self.latlonbb.expand_to_include(Envelope(llp, urp))
self.ordered_layers.append(layer)
self.layers[layername] = layer
def set_center_and_radius(self, lon, lat, radius=None, geographic=True):
coords = Coord(lon, lat)
box = Envelope(coords.x - radius, coords.y - radius, coords.x + radius,
coords.y + radius)
if geographic and not self.proj_obj.geographic:
box = box.forward(self.proj_obj)
self.zoom_to_box(box)
def make_map(map_output, scale=20000, x_center=622000, y_center=6406000):
"Make a map as a function of the scale"
# Compute the scale
page_size = int(PAGE_FORMAT[1])
f = math.sqrt(2)**PAGES[page_size]
# increasing map_x and map_y lead to decreasing font and symbol size: not good
map_x = int(f * 4600) # 4600 is the number of pixels for an A4 length
# if 460: zoom = 13
map_y = int(map_x / math.sqrt(2))
m = Map(map_x, map_y)
load_map(m, MAPNIK_FILE)
# Bounding box (expressed in EPSG:3857, meters)
delta_x = f * 0.295 * scale / math.cos(LATITUDE * 2 * math.pi / 360)
delta_y = delta_x / math.sqrt(2)
xmin = x_center - delta_x / 2
xmax = x_center + delta_x / 2
ymin = y_center - delta_y / 2
ymax = y_center + delta_y / 2
bbox = (Envelope(xmin, ymin, xmax, ymax))
m.zoom_to_box(bbox)
print("Scale = " + str(m.scale()))
render_to_file(m, map_output)
def set_center_and_zoom(self, lon, lat, level=0, geographic=True):
coords = Coord(lon, lat)
if geographic and not self.proj_obj.geographic:
coords = coords.forward(self.proj_obj)
w, h = self.width, self.height
res = self.get_scale_for_zoom_level(level)
box = Envelope(coords.x - 0.5 * w * res, coords.y - 0.5 * h * res,
coords.x + 0.5 * w * res, coords.y + 0.5 * h * res)
self.zoom_to_box(box)
def _buildMap(self, params):
if str(params['crs']) not in self.allowedepsgcodes:
raise OGCException(
'Unsupported CRS "%s" requested.' % str(params['crs']).upper(),
'InvalidCRS')
if params['bbox'][0] >= params['bbox'][2]:
raise OGCException(
"BBOX values don't make sense. minx is greater than maxx.")
if params['bbox'][1] >= params['bbox'][3]:
raise OGCException(
"BBOX values don't make sense. miny is greater than maxy.")
if params.has_key('styles') and len(params['styles']) != len(
params['layers']):
raise OGCException('STYLES length does not match LAYERS length.')
m = Map(params['width'], params['height'], '+init=%s' % params['crs'])
if params.has_key('transparent') and params['transparent'] == 'FALSE':
m.background = params['bgcolor']
else:
m.background = Color(0, 0, 0, 0)
maplayers = self.mapfactory.layers
mapstyles = self.mapfactory.styles
mapaggregatestyles = self.mapfactory.aggregatestyles
for layerindex, layername in enumerate(params['layers']):
try:
layer = maplayers[layername]
except KeyError:
raise OGCException('Layer "%s" not defined.' % layername,
'LayerNotDefined')
reqstyle = params['styles'][layerindex]
if reqstyle and reqstyle not in layer.wmsextrastyles:
raise OGCException(
'Invalid style "%s" requested for layer "%s".' %
(reqstyle, layername), 'StyleNotDefined')
if not reqstyle:
reqstyle = layer.wmsdefaultstyle
if reqstyle in mapaggregatestyles.keys():
for stylename in mapaggregatestyles[reqstyle]:
layer.styles.append(stylename)
else:
layer.styles.append(reqstyle)
for stylename in layer.styles:
if stylename in mapstyles.keys():
m.append_style(stylename, mapstyles[stylename])
else:
raise ServerConfigurationError(
'Layer "%s" refers to non-existent style "%s".' %
(layername, stylename))
m.layers.append(layer)
m.zoom_to_box(
Envelope(params['bbox'][0], params['bbox'][1], params['bbox'][2],
params['bbox'][3]))
return m
def GetMap(self, params):
if params['bbox'][0] >= params['bbox'][2]:
raise OGCException(
"BBOX values don't make sense. minx is greater than maxx.")
if params['bbox'][1] >= params['bbox'][3]:
raise OGCException(
"BBOX values don't make sense. miny is greater than maxy.")
if params.has_key('styles') and len(params['styles']) != len(
params['layers']):
raise OGCException('STYLES length does not match LAYERS length.')
m = Map(params['width'], params['height'])
if params.has_key('transparent') and params['transparent'] == 'FALSE':
m.background = params['bgcolor']
else:
m.background = Color(0, 0, 0, 0)
maplayers = self.mapfactory.layers
mapstyles = self.mapfactory.styles
for layername in params['layers']:
try:
layer = maplayers[layername]
except KeyError:
raise OGCException('Layer "%s" not defined.' % layername,
'LayerNotDefined')
for stylename in layer.styles:
if stylename in mapstyles.keys():
m.append_style(stylename, mapstyles[stylename])
else:
raise ServerConfigurationError(
'Layer "%s" refers to non-existent style "%s".' %
(layername, stylename))
m.layers.append(layer)
m.zoom_to_box(
Envelope(params['bbox'][0], params['bbox'][1], params['bbox'][2],
params['bbox'][3]))
im = Image(params['width'], params['height'])
render(m, im)
im = fromstring('RGBA', (params['width'], params['height']),
rawdata(im))
fh = StringIO()
im.save(fh, PIL_TYPE_MAPPING[params['format']], quality=100)
fh.seek(0)
return Response(params['format'], fh.read())
def zoom_max(self):
max_extent = Envelope(-179.99999694572804, -85.0511285163245,
179.99999694572804, 85.0511287798066)
if not self.proj_obj.geographic:
max_extent = max_extent.forward(self.proj_obj)
self.zoom_to_box(max_extent)
def _buildMap(self, params):
if str(params['crs']) not in self.allowedepsgcodes:
raise OGCException(
'Unsupported CRS "%s" requested.' % str(params['crs']).upper(),
'InvalidCRS')
if params['bbox'][0] >= params['bbox'][2]:
raise OGCException(
"BBOX values don't make sense. minx is greater than maxx.")
if params['bbox'][1] >= params['bbox'][3]:
raise OGCException(
"BBOX values don't make sense. miny is greater than maxy.")
# relax this for now to allow for a set of specific layers (meta layers even)
# to be used without known their styles or putting the right # of commas...
#if params.has_key('styles') and len(params['styles']) != len(params['layers']):
# raise OGCException('STYLES length does not match LAYERS length.')
m = Map(params['width'], params['height'], '+init=%s' % params['crs'])
transparent = params.get('transparent', '').lower() == 'true'
# disable transparent on incompatible formats
if transparent and params.get('format', '') == 'image/jpeg':
transparent = False
if transparent:
# transparent has highest priority
pass
elif params.has_key('bgcolor'):
# if not transparent use bgcolor in url
m.background = params['bgcolor']
else:
# if not bgcolor in url use map background
if mapnik_version() >= 200000:
bgcolor = self.mapfactory.map_attributes.get('bgcolor', None)
else:
bgcolor = self.mapfactory.map_attributes.get(
'background-color', None)
if bgcolor:
m.background = bgcolor
else:
# if not map background defined use white color
m.background = Color(255, 255, 255, 255)
if params.has_key('buffer_size'):
if params['buffer_size']:
m.buffer_size = params['buffer_size']
else:
buffer_ = self.mapfactory.map_attributes.get('buffer_size')
if buffer_:
m.buffer_size = self.mapfactory.map_attributes['buffer_size']
# haiti spec tmp hack! show meta layers without having
# to request huge string to avoid some client truncating it!
if params['layers'] and params['layers'][0] in (
'osm_haiti_overlay', 'osm_haiti_overlay_900913'):
for layer_obj in self.mapfactory.ordered_layers:
layer = copy_layer(layer_obj)
if not hasattr(layer, 'meta_style'):
pass
else:
layer.styles.append(layer.meta_style)
m.append_style(
layer.meta_style,
self.mapfactory.meta_styles[layer.meta_style])
m.layers.append(layer)
# a non WMS spec way of requesting all layers
# uses orderedlayers that preserves original ordering in XML mapfile
elif params['layers'] and params['layers'][0] == '__all__':
for layer_obj in self.mapfactory.ordered_layers:
# if we don't copy the layer here we get
# duplicate layers added to the map because the
# layer is kept around and the styles "pile up"...
layer = copy_layer(layer_obj)
if hasattr(layer, 'meta_style'):
continue
reqstyle = layer.wmsdefaultstyle
if reqstyle in self.mapfactory.aggregatestyles.keys():
for stylename in self.mapfactory.aggregatestyles[reqstyle]:
layer.styles.append(stylename)
else:
layer.styles.append(reqstyle)
for stylename in layer.styles:
if stylename in self.mapfactory.styles.keys():
m.append_style(stylename,
self.mapfactory.styles[stylename])
m.layers.append(layer)
else:
for layerindex, layername in enumerate(params['layers']):
if layername in self.mapfactory.meta_layers:
layer = copy_layer(self.mapfactory.meta_layers[layername])
layer.styles.append(layername)
m.append_style(layername,
self.mapfactory.meta_styles[layername])
else:
try:
# uses unordered dict of layers
# order based on params['layers'] request which
# should be originally informed by order of GetCaps response
layer = copy_layer(self.mapfactory.layers[layername])
except KeyError:
raise OGCException(
'Layer "%s" not defined.' % layername,
'LayerNotDefined')
try:
reqstyle = params['styles'][layerindex]
except IndexError:
reqstyle = ''
if len(layer.wmsextrastyles) > 1 and reqstyle == 'default':
reqstyle = ''
if reqstyle and reqstyle not in layer.wmsextrastyles:
raise OGCException(
'Invalid style "%s" requested for layer "%s".' %
(reqstyle, layername), 'StyleNotDefined')
if not reqstyle:
reqstyle = layer.wmsdefaultstyle
if reqstyle in self.mapfactory.aggregatestyles.keys():
for stylename in self.mapfactory.aggregatestyles[
reqstyle]:
layer.styles.append(stylename)
else:
layer.styles.append(reqstyle)
for stylename in layer.styles:
if stylename in self.mapfactory.styles.keys():
m.append_style(stylename,
self.mapfactory.styles[stylename])
else:
raise ServerConfigurationError(
'Layer "%s" refers to non-existent style "%s".'
% (layername, stylename))
m.layers.append(layer)
m.zoom_to_box(
Envelope(params['bbox'][0], params['bbox'][1], params['bbox'][2],
params['bbox'][3]))
return m
# note: requires mapnik SVN r822 or greater.
# Example of reprojecting the extent for the netherlands in epsg:28992 to google mercator and then back to the original netherlands extent.
import sys
try:
from mapnik import ProjTransform, Projection, Envelope
except ImportError, E:
sys.exit('Requires Mapnik SVN r822 or greater:\n%s' % E)
# http://spatialreference.org/ref/epsg/28992/
# http://mapnik.dbsgeo.com/days/2009-01-25
amersfoort_extent = Envelope(13599.999985, 306799.999985, 277999.999985,
619299.999985)
amersfoort_proj = Projection('+init=epsg:28992')
merc_proj = Projection(
'+proj=merc +a=6378137 +b=6378137 +lat_ts=0.0 +lon_0=0.0 +x_0=0.0 +y_0=0 +k=1.0 +units=m +nadgrids=@null +wktext +no_defs'
)
transform = ProjTransform(amersfoort_proj, merc_proj)
merc_extent = transform.forward(amersfoort_extent)
if transform.backward(merc_extent).__repr__() == amersfoort_extent.__repr__():
print 'Transformation successful!'
print 'Original Dutch Extent: %s' % amersfoort_extent
print 'Merc Extent: %s' % merc_extent
else:
print 'Reprojection failure...'
#!/usr/bin/env python
from mapnik import Coord, Envelope, Projection, forward_, inverse_
import sys
if (len(sys.argv) < 2):
print sys.argv[0] + " <epsg:code> <Coord or Envelope>"
sys.exit(1)
else:
epsg = sys.argv[1]
p = Projection('+init=%s' % epsg)
coord = map(float, sys.argv[2].split(','))
if len(coord) == 2:
long_lat = Coord(*coord)
print 'Forwarded:',
print p.forward(long_lat)
print
print 'Inversed:',
print p.inverse(long_lat)
elif len(coord) == 4:
extent = Envelope(*coord)
print 'Forwarded:',
print forward_(extent, p)
print
print 'Inversed:',
print inverse_(extent, p)
