mapnik/bindings/python/mapnik/printing.py
Dane Springmeyer 9cbef60595 pep8 formatting
2012-03-13 08:22:34 -07:00

1028 lines
41 KiB
Python

# -*- coding: utf-8 -*-
"""Mapnik classes to assist in creating printable maps
basic usage is along the lines of
import mapnik
page = mapnik.printing.PDFPrinter()
m = mapnik.Map(100,100)
mapnik.load_map(m, "my_xml_map_description", True)
m.zoom_all()
page.render_map(m,"my_output_file.pdf")
see the documentation of mapnik.printing.PDFPrinter() for options
"""
from __future__ import absolute_import
from . import render, Map, Box2d, MemoryDatasource, Layer, Feature, Projection, ProjTransform, Coord, Style, Rule, Geometry2d
import math
import os
import tempfile
try:
import cairo
HAS_PYCAIRO_MODULE = True
except ImportError:
HAS_PYCAIRO_MODULE = False
try:
import pangocairo
import pango
HAS_PANGOCAIRO_MODULE = True
except ImportError:
HAS_PANGOCAIRO_MODULE = False
try:
import pyPdf
HAS_PYPDF = True
except ImportError:
HAS_PYPDF = False
class centering:
"""Style of centering to use with the map, the default is constrained
none: map will be placed flush with the margin/box in the top left corner
constrained: map will be centered on the most constrained axis (for a portrait page
and a square map this will be horizontally)
unconstrained: map will be centered on the unconstrained axis
vertical:
horizontal:
both:
"""
none=0
constrained=1
unconstrained=2
vertical=3
horizontal=4
both=5
"""Some predefined page sizes custom sizes can also be passed
a tuple of the page width and height in meters"""
pagesizes = {
"a0": (0.841000,1.189000),
"a0l": (1.189000,0.841000),
"b0": (1.000000,1.414000),
"b0l": (1.414000,1.000000),
"c0": (0.917000,1.297000),
"c0l": (1.297000,0.917000),
"a1": (0.594000,0.841000),
"a1l": (0.841000,0.594000),
"b1": (0.707000,1.000000),
"b1l": (1.000000,0.707000),
"c1": (0.648000,0.917000),
"c1l": (0.917000,0.648000),
"a2": (0.420000,0.594000),
"a2l": (0.594000,0.420000),
"b2": (0.500000,0.707000),
"b2l": (0.707000,0.500000),
"c2": (0.458000,0.648000),
"c2l": (0.648000,0.458000),
"a3": (0.297000,0.420000),
"a3l": (0.420000,0.297000),
"b3": (0.353000,0.500000),
"b3l": (0.500000,0.353000),
"c3": (0.324000,0.458000),
"c3l": (0.458000,0.324000),
"a4": (0.210000,0.297000),
"a4l": (0.297000,0.210000),
"b4": (0.250000,0.353000),
"b4l": (0.353000,0.250000),
"c4": (0.229000,0.324000),
"c4l": (0.324000,0.229000),
"a5": (0.148000,0.210000),
"a5l": (0.210000,0.148000),
"b5": (0.176000,0.250000),
"b5l": (0.250000,0.176000),
"c5": (0.162000,0.229000),
"c5l": (0.229000,0.162000),
"a6": (0.105000,0.148000),
"a6l": (0.148000,0.105000),
"b6": (0.125000,0.176000),
"b6l": (0.176000,0.125000),
"c6": (0.114000,0.162000),
"c6l": (0.162000,0.114000),
"a7": (0.074000,0.105000),
"a7l": (0.105000,0.074000),
"b7": (0.088000,0.125000),
"b7l": (0.125000,0.088000),
"c7": (0.081000,0.114000),
"c7l": (0.114000,0.081000),
"a8": (0.052000,0.074000),
"a8l": (0.074000,0.052000),
"b8": (0.062000,0.088000),
"b8l": (0.088000,0.062000),
"c8": (0.057000,0.081000),
"c8l": (0.081000,0.057000),
"a9": (0.037000,0.052000),
"a9l": (0.052000,0.037000),
"b9": (0.044000,0.062000),
"b9l": (0.062000,0.044000),
"c9": (0.040000,0.057000),
"c9l": (0.057000,0.040000),
"a10": (0.026000,0.037000),
"a10l": (0.037000,0.026000),
"b10": (0.031000,0.044000),
"b10l": (0.044000,0.031000),
"c10": (0.028000,0.040000),
"c10l": (0.040000,0.028000),
"letter": (0.216,0.279),
"letterl": (0.279,0.216),
"legal": (0.216,0.356),
"legall": (0.356,0.216),
}
"""size of a pt in meters"""
pt_size=0.0254/72.0
def m2pt(x):
"""convert distance from meters to points"""
return x/pt_size
def pt2m(x):
"""convert distance from points to meters"""
return x*pt_size
def m2in(x):
"""convert distance from meters to inches"""
return x/0.0254
def m2px(x,resolution):
"""convert distance from meters to pixels at the given resolution in DPI/PPI"""
return m2in(x)*resolution
class resolutions:
"""some predefined resolutions in DPI"""
dpi72=72
dpi150=150
dpi300=300
dpi600=600
def any_scale(scale):
"""Scale helper function that allows any scale"""
return scale
def sequence_scale(scale,scale_sequence):
"""Default scale helper, this rounds scale to a 'sensible' value"""
factor = math.floor(math.log10(scale))
norm = scale/(10**factor)
for s in scale_sequence:
if norm <= s:
return s*10**factor
return scale_sequence[0]*10**(factor+1)
def default_scale(scale):
"""Default scale helper, this rounds scale to a 'sensible' value"""
return sequence_scale(scale, (1,1.25,1.5,1.75,2,2.5,3,4,5,6,7.5,8,9,10))
def deg_min_sec_scale(scale):
for x in (1.0/3600,
2.0/3600,
5.0/3600,
10.0/3600,
30.0/3600,
1.0/60,
2.0/60,
5.0/60,
10.0/60,
30.0/60,
1,
2,
5,
10,
30,
60
):
if scale < x:
return x
else:
return x
def format_deg_min_sec(value):
deg = math.floor(value)
min = math.floor((value-deg)/(1.0/60))
sec = int((value - deg*1.0/60)/1.0/3600)
return "%d°%d'%d\"" % (deg,min,sec)
def round_grid_generator(first,last,step):
val = (math.floor(first / step) + 1) * step
yield val
while val < last:
val += step
yield val
def convert_pdf_pages_to_layers(filename,output_name=None,layer_names=(),reverse_all_but_last=True):
"""
opens the given multipage PDF and converts each page to be a layer in a single page PDF
layer_names should be a sequence of the user visible names of the layers, if not given
or if shorter than num pages generic names will be given to the unnamed layers
if output_name is not provided a temporary file will be used for the conversion which
will then be copied back over the source file.
requires pyPdf >= 1.13 to be available"""
if not HAS_PYPDF:
raise Exception("pyPdf Not available")
infile = file(filename, 'rb')
if output_name:
outfile = file(output_name, 'wb')
else:
(outfd,outfilename) = tempfile.mkstemp(dir=os.path.dirname(filename))
outfile = os.fdopen(outfd,'wb')
i = pyPdf.PdfFileReader(infile)
o = pyPdf.PdfFileWriter()
template_page_size = i.pages[0].mediaBox
op = o.addBlankPage(width=template_page_size.getWidth(),height=template_page_size.getHeight())
contentkey = pyPdf.generic.NameObject('/Contents')
resourcekey = pyPdf.generic.NameObject('/Resources')
propertieskey = pyPdf.generic.NameObject('/Properties')
op[contentkey] = pyPdf.generic.ArrayObject()
op[resourcekey] = pyPdf.generic.DictionaryObject()
properties = pyPdf.generic.DictionaryObject()
ocgs = pyPdf.generic.ArrayObject()
for (i, p) in enumerate(i.pages):
# first start an OCG for the layer
ocgname = pyPdf.generic.NameObject('/oc%d' % i)
ocgstart = pyPdf.generic.DecodedStreamObject()
ocgstart._data = "/OC %s BDC\n" % ocgname
ocgend = pyPdf.generic.DecodedStreamObject()
ocgend._data = "EMC\n"
if isinstance(p['/Contents'],pyPdf.generic.ArrayObject):
p[pyPdf.generic.NameObject('/Contents')].insert(0,ocgstart)
p[pyPdf.generic.NameObject('/Contents')].append(ocgend)
else:
p[pyPdf.generic.NameObject('/Contents')] = pyPdf.generic.ArrayObject((ocgstart,p['/Contents'],ocgend))
op.mergePage(p)
ocg = pyPdf.generic.DictionaryObject()
ocg[pyPdf.generic.NameObject('/Type')] = pyPdf.generic.NameObject('/OCG')
if len(layer_names) > i:
ocg[pyPdf.generic.NameObject('/Name')] = pyPdf.generic.TextStringObject(layer_names[i])
else:
ocg[pyPdf.generic.NameObject('/Name')] = pyPdf.generic.TextStringObject('Layer %d' % (i+1))
indirect_ocg = o._addObject(ocg)
properties[ocgname] = indirect_ocg
ocgs.append(indirect_ocg)
op[resourcekey][propertieskey] = o._addObject(properties)
ocproperties = pyPdf.generic.DictionaryObject()
ocproperties[pyPdf.generic.NameObject('/OCGs')] = ocgs
defaultview = pyPdf.generic.DictionaryObject()
defaultview[pyPdf.generic.NameObject('/Name')] = pyPdf.generic.TextStringObject('Default')
defaultview[pyPdf.generic.NameObject('/BaseState ')] = pyPdf.generic.NameObject('/ON ')
defaultview[pyPdf.generic.NameObject('/ON')] = ocgs
if reverse_all_but_last:
defaultview[pyPdf.generic.NameObject('/Order')] = pyPdf.generic.ArrayObject(reversed(ocgs[:-1]))
defaultview[pyPdf.generic.NameObject('/Order')].append(ocgs[-1])
else:
defaultview[pyPdf.generic.NameObject('/Order')] = pyPdf.generic.ArrayObject(reversed(ocgs))
defaultview[pyPdf.generic.NameObject('/OFF')] = pyPdf.generic.ArrayObject()
ocproperties[pyPdf.generic.NameObject('/D')] = o._addObject(defaultview)
o._root.getObject()[pyPdf.generic.NameObject('/OCProperties')] = o._addObject(ocproperties)
o.write(outfile)
outfile.close()
infile.close()
if not output_name:
os.rename(outfilename, filename)
class PDFPrinter:
"""Main class for creating PDF print outs, basically contruct an instance
with appropriate options and then call render_map with your mapnik map
"""
def __init__(self,
pagesize=pagesizes["a4"],
margin=0.005,
box=None,
percent_box=None,
scale=default_scale,
resolution=resolutions.dpi72,
preserve_aspect=True,
centering=centering.constrained,
is_latlon=False,
use_ocg_layers=False):
"""Creates a cairo surface and context to render a PDF with.
pagesize: tuple of page size in meters, see predefined sizes in pagessizes dict (default a4)
margin: page margin in meters (default 0.01)
box: box within the page to render the map into (will not render over margin). This should be
a Mapnik Box2d object. Default is the full page within the margin
percent_box: as per box, but specified as a percent (0->1) of the full page size. If both box
and percent_box are specified percent_box will be used.
scale: scale helper to use when rounding the map scale. This should be a function that
takes a single float and returns a float which is at least as large as the value
passed in. This is a 1:x scale.
resolution: the resolution to render non vector elements at (in DPI), defaults to 72 DPI
preserve_aspect: whether to preserve map aspect ratio. This defaults to True and it
is recommended you do not change it unless you know what you are doing
scales and so on will not work if this is False.
centering: Centering rules for maps where the scale rounding has reduced the map size.
This should be a value from the centering class. The default is to center on the
maps constrained axis, typically this will be horizontal for portrait pages and
vertical for landscape pages.
is_latlon: Is the map in lat lon degrees. If true magic anti meridian logic is enabled
use_ocg_layers: Create OCG layers in the PDF, requires pyPdf >= 1.13
"""
self._pagesize = pagesize
self._margin = margin
self._box = box
self._scale = scale
self._resolution = resolution
self._preserve_aspect = preserve_aspect
self._centering = centering
self._is_latlon = is_latlon
self._use_ocg_layers = use_ocg_layers
self._s = None
self._layer_names = []
self._filename = None
self.map_box = None
self.scale = None
# don't both to round the scale if they are not preserving the aspect ratio
if not preserve_aspect:
self._scale = any_scale
if percent_box:
self._box = Box2d(percent_box[0]*pagesize[0],percent_box[1]*pagesize[1],
percent_box[2]*pagesize[0],percent_box[3]*pagesize[1])
if not HAS_PYCAIRO_MODULE:
raise Exception("PDF rendering only available when pycairo is available")
self.font_name = "DejaVu Sans"
def finish(self):
if self._s:
self._s.finish()
self._s = None
if self._use_ocg_layers:
convert_pdf_pages_to_layers(self._filename,layer_names=self._layer_names + ["Legend and Information"],reverse_all_but_last=True)
def add_geospatial_pdf_header(self,m,filename,epsg=None,wkt=None):
""" Postprocessing step to add geospatial PDF information to PDF file as per
PDF standard 1.7 extension level 3 (also in draft PDF v2 standard at time of writing)
one of either the epsg code or wkt text for the projection must be provided
Should be called *after* the page has had .finish() called"""
if HAS_PYPDF and (epsg or wkt):
infile=file(filename,'rb')
(outfd,outfilename) = tempfile.mkstemp(dir=os.path.dirname(filename))
outfile = os.fdopen(outfd,'wb')
i=pyPdf.PdfFileReader(infile)
o=pyPdf.PdfFileWriter()
# preserve OCProperties at document root if we have one
if i.trailer['/Root'].has_key(pyPdf.generic.NameObject('/OCProperties')):
o._root.getObject()[pyPdf.generic.NameObject('/OCProperties')] = i.trailer['/Root'].getObject()[pyPdf.generic.NameObject('/OCProperties')]
for p in i.pages:
gcs = pyPdf.generic.DictionaryObject()
gcs[pyPdf.generic.NameObject('/Type')]=pyPdf.generic.NameObject('/PROJCS')
if epsg:
gcs[pyPdf.generic.NameObject('/EPSG')]=pyPdf.generic.NumberObject(int(epsg))
if wkt:
gcs[pyPdf.generic.NameObject('/WKT')]=pyPdf.generic.TextStringObject(wkt)
measure = pyPdf.generic.DictionaryObject()
measure[pyPdf.generic.NameObject('/Type')]=pyPdf.generic.NameObject('/Measure')
measure[pyPdf.generic.NameObject('/Subtype')]=pyPdf.generic.NameObject('/GEO')
measure[pyPdf.generic.NameObject('/GCS')]=gcs
bounds=pyPdf.generic.ArrayObject()
for x in (0.0,0.0,0.0,1.0,1.0,1.0,1.0,0.0):
bounds.append(pyPdf.generic.FloatObject(str(x)))
measure[pyPdf.generic.NameObject('/Bounds')]=bounds
measure[pyPdf.generic.NameObject('/LPTS')]=bounds
gpts=pyPdf.generic.ArrayObject()
proj=Projection(m.srs)
env=m.envelope()
for x in ((env.minx, env.miny), (env.minx, env.maxy), (env.maxx, env.maxy), (env.maxx, env.miny)):
latlon_corner=proj.inverse(Coord(*x))
# these are in lat,lon order according to the standard
gpts.append(pyPdf.generic.FloatObject(str(latlon_corner.y)))
gpts.append(pyPdf.generic.FloatObject(str(latlon_corner.x)))
measure[pyPdf.generic.NameObject('/GPTS')]=gpts
vp=pyPdf.generic.DictionaryObject()
vp[pyPdf.generic.NameObject('/Type')]=pyPdf.generic.NameObject('/Viewport')
bbox=pyPdf.generic.ArrayObject()
for x in self.map_box:
bbox.append(pyPdf.generic.FloatObject(str(x)))
vp[pyPdf.generic.NameObject('/BBox')]=bbox
vp[pyPdf.generic.NameObject('/Measure')]=measure
vpa = pyPdf.generic.ArrayObject()
vpa.append(vp)
p[pyPdf.generic.NameObject('/VP')]=vpa
o.addPage(p)
o.write(outfile)
infile=None
outfile.close()
os.rename(outfilename,filename)
def get_context(self):
"""allow access so that extra 'bits' can be rendered to the page directly"""
return cairo.Context(self._s)
def get_width(self):
return self._pagesize[0]
def get_height(self):
return self._pagesize[1]
def get_margin(self):
return self._margin
def write_text(self,ctx,text,box_width=None,size=10, fill_color=(0.0, 0.0, 0.0), alignment=None):
if HAS_PANGOCAIRO_MODULE:
(attr,t,accel) = pango.parse_markup(text)
pctx = pangocairo.CairoContext(ctx)
l = pctx.create_layout()
l.set_attributes(attr)
fd = pango.FontDescription("%s %d" % (self.font_name,size))
l.set_font_description(fd)
if box_width:
l.set_width(int(box_width*pango.SCALE))
if alignment:
l.set_alignment(alignment)
pctx.update_layout(l)
l.set_text(t)
pctx.set_source_rgb(*fill_color)
pctx.show_layout(l)
return l.get_pixel_extents()[0]
else:
ctx.rel_move_to(0,size)
ctx.select_font_face(self.font_name, cairo.FONT_SLANT_NORMAL, cairo.FONT_WEIGHT_NORMAL)
ctx.set_font_size(size)
ctx.show_text(text)
ctx.rel_move_to(0,size)
return (0,0,len(text)*size,size)
def _get_context(self):
if HAS_PANGOCAIRO_MODULE:
return
elif HAS_PYCAIRO_MODULE:
return cairo.Context(self._s)
return None
def _get_render_area(self):
"""return a bounding box with the area of the page we are allowed to render out map to
in page coordinates (i.e. meters)
"""
# take off our page margins
render_area = Box2d(self._margin,self._margin,self._pagesize[0]-self._margin,self._pagesize[1]-self._margin)
#then if user specified a box to render get intersection with that
if self._box:
return render_area.intersect(self._box)
return render_area
def _get_render_area_size(self):
"""Get the width and height (in meters) of the area we can render the map to, returned as a tuple"""
render_area = self._get_render_area()
return (render_area.width(),render_area.height())
def _is_h_contrained(self,m):
"""Test if the map size is constrained on the horizontal or vertical axes"""
available_area = self._get_render_area_size()
map_aspect = m.envelope().width()/m.envelope().height()
page_aspect = available_area[0]/available_area[1]
return map_aspect > page_aspect
def _get_meta_info_corner(self,render_size,m):
"""Get the corner (in page coordinates) of a possibly
sensible place to render metadata such as a legend or scale"""
(x,y) = self._get_render_corner(render_size,m)
if self._is_h_contrained(m):
y += render_size[1]+0.005
x = self._margin
else:
x += render_size[0]+0.005
y = self._margin
return (x,y)
def _get_render_corner(self,render_size,m):
"""Get the corner of the box we should render our map into"""
available_area = self._get_render_area()
x=available_area[0]
y=available_area[1]
h_is_contrained = self._is_h_contrained(m)
if (self._centering == centering.both or
self._centering == centering.horizontal or
(self._centering == centering.constrained and h_is_contrained) or
(self._centering == centering.unconstrained and not h_is_contrained)):
x+=(available_area.width()-render_size[0])/2
if (self._centering == centering.both or
self._centering == centering.vertical or
(self._centering == centering.constrained and not h_is_contrained) or
(self._centering == centering.unconstrained and h_is_contrained)):
y+=(available_area.height()-render_size[1])/2
return (x,y)
def _get_map_pixel_size(self, width_page_m, height_page_m):
"""for a given map size in paper coordinates return a tuple of the map 'pixel' size we
should create at the defined resolution"""
return (int(m2px(width_page_m,self._resolution)), int(m2px(height_page_m,self._resolution)))
def render_map(self,m, filename):
"""Render the given map to filename"""
# store this for later so we can post process the PDF
self._filename = filename
# work out the best scale to render out map at given the available space
(eff_width,eff_height) = self._get_render_area_size()
map_aspect = m.envelope().width()/m.envelope().height()
page_aspect = eff_width/eff_height
scalex=m.envelope().width()/eff_width
scaley=m.envelope().height()/eff_height
scale=max(scalex,scaley)
rounded_mapscale=self._scale(scale)
scalefactor = scale/rounded_mapscale
mapw=eff_width*scalefactor
maph=eff_height*scalefactor
if self._preserve_aspect:
if map_aspect > page_aspect:
maph=mapw*(1/map_aspect)
else:
mapw=maph*map_aspect
# set the map size so that raster elements render at the correct resolution
m.resize(*self._get_map_pixel_size(mapw,maph))
# calculate the translation for the map starting point
(tx,ty) = self._get_render_corner((mapw,maph),m)
# create our cairo surface and context and then render the map into it
self._s = cairo.PDFSurface(filename, m2pt(self._pagesize[0]),m2pt(self._pagesize[1]))
ctx=cairo.Context(self._s)
for l in m.layers:
# extract the layer names for naming layers if we use OCG
self._layer_names.append(l.name)
layer_map = Map(m.width,m.height,m.srs)
layer_map.layers.append(l)
for s in l.styles:
layer_map.append_style(s,m.find_style(s))
layer_map.zoom_to_box(m.envelope())
def render_map():
ctx.save()
ctx.translate(m2pt(tx),m2pt(ty))
#cairo defaults to 72dpi
ctx.scale(72.0/self._resolution,72.0/self._resolution)
render(layer_map, ctx)
ctx.restore()
# antimeridian
render_map()
if self._is_latlon and (m.envelope().minx < -180 or m.envelope().maxx > 180):
old_env = m.envelope()
if m.envelope().minx < -180:
delta = 360
else:
delta = -360
m.zoom_to_box(Box2d(old_env.minx+delta,old_env.miny,old_env.maxx+delta,old_env.maxy))
render_map()
# restore the original env
m.zoom_to_box(old_env)
if self._use_ocg_layers:
self._s.show_page()
self.scale = rounded_mapscale
self.map_box = Box2d(tx,ty,tx+mapw,ty+maph)
def render_on_map_lat_lon_grid(self,m,dec_degrees=True):
# don't render lat_lon grid if we are already in latlon
if self._is_latlon:
return
p2=Projection(m.srs)
latlon_bounds = p2.inverse(m.envelope())
if p2.inverse(m.envelope().center()).x > latlon_bounds.maxx:
latlon_bounds = Box2d(latlon_bounds.maxx,latlon_bounds.miny,latlon_bounds.minx+360,latlon_bounds.maxy)
if p2.inverse(m.envelope().center()).y > latlon_bounds.maxy:
latlon_bounds = Box2d(latlon_bounds.miny,latlon_bounds.maxy,latlon_bounds.maxx,latlon_bounds.miny+360)
latlon_mapwidth = latlon_bounds.width()
# render an extra 20% so we generally won't miss the ends of lines
latlon_buffer = 0.2*latlon_mapwidth
if dec_degrees:
latlon_divsize = default_scale(latlon_mapwidth/7.0)
else:
latlon_divsize = deg_min_sec_scale(latlon_mapwidth/7.0)
latlon_interpsize = latlon_mapwidth/m.width
self._render_lat_lon_axis(m,p2,latlon_bounds.minx,latlon_bounds.maxx,latlon_bounds.miny,latlon_bounds.maxy,latlon_buffer,latlon_interpsize,latlon_divsize,dec_degrees,True)
self._render_lat_lon_axis(m,p2,latlon_bounds.miny,latlon_bounds.maxy,latlon_bounds.minx,latlon_bounds.maxx,latlon_buffer,latlon_interpsize,latlon_divsize,dec_degrees,False)
def _render_lat_lon_axis(self,m,p2,x1,x2,y1,y2,latlon_buffer,latlon_interpsize,latlon_divsize,dec_degrees,is_x_axis):
ctx=cairo.Context(self._s)
ctx.set_source_rgb(1,0,0)
ctx.set_line_width(1)
latlon_labelsize = 6
ctx.translate(m2pt(self.map_box.minx),m2pt(self.map_box.miny))
ctx.rectangle(0,0,m2pt(self.map_box.width()),m2pt(self.map_box.height()))
ctx.clip()
ctx.select_font_face("DejaVu", cairo.FONT_SLANT_NORMAL, cairo.FONT_WEIGHT_NORMAL)
ctx.set_font_size(latlon_labelsize)
box_top = self.map_box.height()
if not is_x_axis:
ctx.translate(m2pt(self.map_box.width()/2),m2pt(self.map_box.height()/2))
ctx.rotate(-math.pi/2)
ctx.translate(-m2pt(self.map_box.height()/2),-m2pt(self.map_box.width()/2))
box_top = self.map_box.width()
for xvalue in round_grid_generator(x1 - latlon_buffer,x2 + latlon_buffer,latlon_divsize):
yvalue = y1 - latlon_buffer
start_cross = None
end_cross = None
while yvalue < y2+latlon_buffer:
if is_x_axis:
start = m.view_transform().forward(p2.forward(Coord(xvalue,yvalue)))
else:
temp = m.view_transform().forward(p2.forward(Coord(yvalue,xvalue)))
start = Coord(m2pt(self.map_box.height())-temp.y,temp.x)
yvalue += latlon_interpsize
if is_x_axis:
end = m.view_transform().forward(p2.forward(Coord(xvalue,yvalue)))
else:
temp = m.view_transform().forward(p2.forward(Coord(yvalue,xvalue)))
end = Coord(m2pt(self.map_box.height())-temp.y,temp.x)
ctx.move_to(start.x,start.y)
ctx.line_to(end.x,end.y)
ctx.stroke()
if cmp(start.y, 0) != cmp(end.y,0):
start_cross = end.x
if cmp(start.y,m2pt(self.map_box.height())) != cmp(end.y, m2pt(self.map_box.height())):
end_cross = end.x
if dec_degrees:
line_text = "%g" % (xvalue)
else:
line_text = format_deg_min_sec(xvalue)
if start_cross:
ctx.move_to(start_cross+2,latlon_labelsize)
ctx.show_text(line_text)
if end_cross:
ctx.move_to(end_cross+2,m2pt(box_top)-2)
ctx.show_text(line_text)
def render_on_map_scale(self,m):
(div_size,page_div_size) = self._get_sensible_scalebar_size(m)
first_value_x = (math.floor(m.envelope().minx / div_size) + 1) * div_size
first_value_x_percent = (first_value_x-m.envelope().minx)/m.envelope().width()
self._render_scale_axis(first_value_x,first_value_x_percent,self.map_box.minx,self.map_box.maxx,page_div_size,div_size,self.map_box.miny,self.map_box.maxy,True)
first_value_y = (math.floor(m.envelope().miny / div_size) + 1) * div_size
first_value_y_percent = (first_value_y-m.envelope().miny)/m.envelope().height()
self._render_scale_axis(first_value_y,first_value_y_percent,self.map_box.miny,self.map_box.maxy,page_div_size,div_size,self.map_box.minx,self.map_box.maxx,False)
if self._use_ocg_layers:
self._s.show_page()
self._layer_names.append("Coordinate Grid Overlay")
def _get_sensible_scalebar_size(self,m,width=-1):
# aim for about 8 divisions across the map
# also make sure we can fit the bar with in page area width if specified
div_size = sequence_scale(m.envelope().width()/8, [1,2,5])
page_div_size = self.map_box.width()*div_size/m.envelope().width()
while width > 0 and page_div_size > width:
div_size /=2
page_div_size /= 2
return (div_size,page_div_size)
def _render_box(self,ctx,x,y,w,h,text=None,stroke_color=(0,0,0),fill_color=(0,0,0)):
ctx.set_line_width(1)
ctx.set_source_rgb(*fill_color)
ctx.rectangle(x,y,w,h)
ctx.fill()
ctx.set_source_rgb(*stroke_color)
ctx.rectangle(x,y,w,h)
ctx.stroke()
if text:
ctx.move_to(x+1,y)
self.write_text(ctx,text,fill_color=[1-z for z in fill_color],size=h-2)
def _render_scale_axis(self,first,first_percent,start,end,page_div_size,div_size,boundary_start,boundary_end,is_x_axis):
prev = start
text = None
fill=(0,0,0)
border_size=8
value = first_percent * (end-start) + start
label_value = first-div_size
if self._is_latlon and label_value < -180:
label_value += 360
ctx=cairo.Context(self._s)
if not is_x_axis:
ctx.translate(m2pt(self.map_box.center().x),m2pt(self.map_box.center().y))
ctx.rotate(-math.pi/2)
ctx.translate(-m2pt(self.map_box.center().y),-m2pt(self.map_box.center().x))
while value < end:
ctx.move_to(m2pt(value),m2pt(boundary_start))
ctx.line_to(m2pt(value),m2pt(boundary_end))
ctx.set_source_rgb(0.5,0.5,0.5)
ctx.set_line_width(1)
ctx.stroke()
for bar in (m2pt(boundary_start)-border_size,m2pt(boundary_end)):
self._render_box(ctx,m2pt(prev),bar,m2pt(value-prev),border_size,text,fill_color=fill)
prev = value
value+=page_div_size
fill = [1-z for z in fill]
label_value += div_size
if self._is_latlon and label_value > 180:
label_value -= 360
text = "%d" % label_value
else:
for bar in (m2pt(boundary_start)-border_size,m2pt(boundary_end)):
self._render_box(ctx,m2pt(prev),bar,m2pt(end-prev),border_size,fill_color=fill)
def render_scale(self,m,ctx=None,width=0.05):
""" m: map to render scale for
ctx: A cairo context to render the scale to. If this is None (the default) then
automatically create a context and choose the best location for the scale bar.
width: Width of area available to render scale bar in (in m)
will return the size of the rendered scale block in pts
"""
(w,h) = (0,0)
# don't render scale if we are lat lon
# dont report scale if we have warped the aspect ratio
if self._preserve_aspect and not self._is_latlon:
bar_size=8.0
box_count=3
if ctx is None:
ctx=cairo.Context(self._s)
(tx,ty) = self._get_meta_info_corner((self.map_box.width(),self.map_box.height()),m)
ctx.translate(tx,ty)
(div_size,page_div_size) = self._get_sensible_scalebar_size(m, width/box_count)
div_unit = "m"
if div_size > 1000:
div_size /= 1000
div_unit = "km"
text = "0%s" % div_unit
ctx.save()
if width > 0:
ctx.translate(m2pt(width-box_count*page_div_size)/2,0)
for ii in range(box_count):
fill=(ii%2,)*3
self._render_box(ctx, m2pt(ii*page_div_size), h, m2pt(page_div_size), bar_size, text, fill_color=fill)
fill = [1-z for z in fill]
text = "%g%s" % ((ii+1)*div_size,div_unit)
#else:
# self._render_box(ctx, m2pt(box_count*page_div_size), h, m2pt(page_div_size), bar_size, text, fill_color=(1,1,1), stroke_color=(1,1,1))
w = (box_count)*page_div_size
h += bar_size
ctx.restore()
if width > 0:
box_width=m2pt(width)
else:
box_width = None
font_size=6
ctx.move_to(0,h)
if HAS_PANGOCAIRO_MODULE:
alignment = pango.ALIGN_CENTER
else:
alignment = None
text_ext=self.write_text(ctx,"Scale 1:%d" % self.scale,box_width=box_width,size=font_size, alignment=alignment)
h+=text_ext[3]+2
return (w,h)
def render_legend(self,m, page_break=False, ctx=None, collumns=1,width=None, height=None, item_per_rule=False, attribution={}, legend_item_box_size=(0.015,0.0075)):
""" m: map to render legend for
ctx: A cairo context to render the legend to. If this is None (the default) then
automatically create a context and choose the best location for the legend.
width: Width of area available to render legend in (in m)
page_break: move to next page if legen over flows this one
collumns: number of collumns available in legend box
attribution: additional text that will be rendered in gray under the layer name. keyed by layer name
legend_item_box_size: two tuple with width and height of legend item box size in meters
will return the size of the rendered block in pts
"""
(w,h) = (0,0)
if self._s:
if ctx is None:
ctx=cairo.Context(self._s)
(tx,ty) = self._get_meta_info_corner((self.map_box.width(),self.map_box.height()),m)
ctx.translate(m2pt(tx),m2pt(ty))
width = self._pagesize[0]-2*tx
height = self._pagesize[1]-self._margin-ty
x=0
y=0
if width:
cwidth = width/collumns
w=m2pt(width)
else:
cwidth = None
current_collumn = 0
processed_layers = []
for l in reversed(m.layers):
have_layer_header = False
added_styles={}
layer_title = l.name
if layer_title in processed_layers:
continue
processed_layers.append(layer_title)
# check through the features to find which combinations of styles are active
# for each unique combination add a legend entry
for f in l.datasource.all_features():
if f.num_geometries() > 0:
active_rules = []
rule_text = ""
for s in l.styles:
st = m.find_style(s)
for r in st.rules:
# we need to do the scale test here as well so we don't
# add unused scale rules to the legend description
if ((not r.filter) or r.filter.evaluate(f) == '1') and \
r.min_scale <= m.scale_denominator() and m.scale_denominator() < r.max_scale:
active_rules.append((s,r.name))
if r.filter and str(r.filter) != "true":
if len(rule_text) > 0:
rule_text += " AND "
if r.name:
rule_text += r.name
else:
rule_text += str(r.filter)
active_rules = tuple(active_rules)
if added_styles.has_key(active_rules):
continue
added_styles[active_rules] = (f,rule_text)
if not item_per_rule:
break
else:
added_styles[l] = (None,None)
legend_items = added_styles.keys()
legend_items.sort()
for li in legend_items:
if True:
(f,rule_text) = added_styles[li]
legend_map_size = (int(m2pt(legend_item_box_size[0])),int(m2pt(legend_item_box_size[1])))
lemap=Map(legend_map_size[0],legend_map_size[1],srs=m.srs)
if m.background:
lemap.background = m.background
# the buffer is needed to ensure that text labels that overflow the edge of the
# map still render for the legend
lemap.buffer_size=1000
for s in l.styles:
sty=m.find_style(s)
lestyle = Style()
for r in sty.rules:
for sym in r.symbols:
try:
sym.avoid_edges=False
except:
print "**** Cant set avoid edges for rule", r.name
if r.min_scale <= m.scale_denominator() and m.scale_denominator() < r.max_scale:
lerule = r
lerule.min_scale = 0
lerule.max_scale = float("inf")
lestyle.rules.append(lerule)
lemap.append_style(s,lestyle)
ds = MemoryDatasource()
if f is None:
ds=l.datasource
layer_srs = l.srs
elif f.envelope().width() == 0:
ds.add_feature(Feature(f.id(),Geometry2d.from_wkt("POINT(0 0)"),**f.attributes))
lemap.zoom_to_box(Box2d(-1,-1,1,1))
layer_srs = m.srs
else:
ds.add_feature(f)
layer_srs = l.srs
lelayer = Layer("LegendLayer",layer_srs)
lelayer.datasource = ds
for s in l.styles:
lelayer.styles.append(s)
lemap.layers.append(lelayer)
if f is None or f.envelope().width() != 0:
lemap.zoom_all()
lemap.zoom(1.1)
item_size = legend_map_size[1]
if not have_layer_header:
item_size += 8
if y+item_size > m2pt(height):
current_collumn += 1
y=0
if current_collumn >= collumns:
if page_break:
self._s.show_page()
x=0
current_collumn = 0
else:
break
if not have_layer_header and item_per_rule:
ctx.move_to(x+m2pt(current_collumn*cwidth),y)
e=self.write_text(ctx, l.name, m2pt(cwidth), 8)
y+=e[3]+2
have_layer_header = True
ctx.save()
ctx.translate(x+m2pt(current_collumn*cwidth),y)
#extra save around map render as it sets up a clip box and doesn't clear it
ctx.save()
render(lemap, ctx)
ctx.restore()
ctx.rectangle(0,0,*legend_map_size)
ctx.set_source_rgb(0.5,0.5,0.5)
ctx.set_line_width(1)
ctx.stroke()
ctx.restore()
ctx.move_to(x+legend_map_size[0]+m2pt(current_collumn*cwidth)+2,y)
legend_entry_size = legend_map_size[1]
legend_text_size = 0
if not item_per_rule:
rule_text = layer_title
if rule_text:
e=self.write_text(ctx, rule_text, m2pt(cwidth-legend_item_box_size[0]-0.005), 6)
legend_text_size += e[3]
ctx.rel_move_to(0,e[3])
if attribution.has_key(layer_title):
e=self.write_text(ctx, attribution[layer_title], m2pt(cwidth-legend_item_box_size[0]-0.005), 6, fill_color=(0.5,0.5,0.5))
legend_text_size += e[3]
if legend_text_size > legend_entry_size:
legend_entry_size=legend_text_size
y+=legend_entry_size +2
if y > h:
h = y
return (w,h)