mapnik/tests/python_tests/glyph_symbolizer_test.py

#encoding: utf8
#!/usr/bin/env python

from nose.tools import *

from utilities import execution_path, save_data, contains_word

import os, mapnik

def test_renders_with_agg():
    sym = mapnik.GlyphSymbolizer("DejaVu Sans Condensed",
                                  mapnik.Expression("'í'"))
    sym.allow_overlap = True
    sym.angle = mapnik.Expression("[azimuth]+90") #+90 so the top of the glyph points upwards
    sym.size = mapnik.Expression("[value]")
    sym.color = mapnik.Expression("'#ff0000'")

    _map = create_map_and_append_symbolyzer(sym)
    if _map:
        im = mapnik.Image(_map.width,_map.height)
        mapnik.render(_map, im)
        save_data('agg_glyph_symbolizer.png', im.tostring('png'))
        assert contains_word('\xff\x00\x00\xff', im.tostring())

def test_renders_with_cairo():
    if not mapnik.has_pycairo():
        return
    sym = mapnik.GlyphSymbolizer("DejaVu Sans Condensed",
                                  mapnik.Expression("'í'"))
    sym.allow_overlap = True
    sym.angle = mapnik.Expression("[azimuth]+90") #+90 so the top of the glyph points upwards
    sym.size = mapnik.Expression("[value]")
    sym.color = mapnik.Expression("'#ff0000'")
    _map = create_map_and_append_symbolyzer(sym)
    if _map:
        from cStringIO import StringIO
        import cairo
        surface = cairo.ImageSurface(cairo.FORMAT_ARGB32, 256, 256)
        mapnik.render(_map, surface)
        im = mapnik.Image.from_cairo(surface)
        save_data('cairo_glyph_symbolizer.png', im.tostring('png'))
        assert contains_word('\xff\x00\x00\xff', im.tostring())

def test_load_save_load_map():
    map = mapnik.Map(256,256)
    in_map = "../data/good_maps/glyph_symbolizer.xml"
    try:
        mapnik.load_map(map, in_map)
        style = map.find_style('arrows')
        sym = style.rules[0].symbols[0]
        assert isinstance(sym, mapnik.GlyphSymbolizer)
        assert sym.angle_mode == mapnik.angle_mode.AZIMUTH
    
        out_map = mapnik.save_map_to_string(map).decode('utf8')
        map = mapnik.Map(256,256)
        mapnik.load_map_from_string(map, out_map.encode('utf8'))
        assert 'GlyphSymbolizer' in out_map
        # make sure non-ascii characters are well supported since most interesting
        # glyphs for symbology are usually in that range
        assert u'í' in out_map, out_map
    except RuntimeError, e:
        # only test datasources that we have installed
        if not 'Could not create datasource' in str(e):
            raise RuntimeError(e)

#
# Utilities and setup code
#

def setup():
    # All of the paths used are relative, if we run the tests
    # from another directory we need to chdir()
    os.chdir(execution_path('.'))
    
def create_map_and_append_symbolyzer(sym):
    srs = '+init=epsg:32630'
    lyr = mapnik.Layer('arrows')
    try:
        lyr.datasource = mapnik.Shapefile(
            file = '../data/shp/arrows.shp',
            )
        lyr.srs = srs
        _map = mapnik.Map(256,256, srs)
        style = mapnik.Style()
        rule = mapnik.Rule()
        rule.symbols.append(sym)
    
        # put a test symbolizer to see what is the azimuth being read
        ts = mapnik.TextSymbolizer(mapnik.Expression('[azimuth]'),
                                   "DejaVu Sans Book",
                                   10,
                                   mapnik.Color("black"))
        ts.allow_overlap = True
        rule.symbols.append(ts)
    
        style.rules.append(rule)
        _map.append_style('foo', style)
        lyr.styles.append('foo')
        _map.layers.append(lyr)
        _map.zoom_to_box(mapnik.Box2d(0,0,8,8))
        return _map
    except RuntimeError, e:
        # only test datasources that we have installed
        if not 'Could not create datasource' in str(e):
            raise RuntimeError(e)

if __name__ == "__main__":
    setup()
    [eval(run)() for run in dir() if 'test_' in run]