Python mapnik2.render函数代码示例

  def index(self):
    x   = cherrypy.request.headers['x']
    y   = cherrypy.request.headers['y']
    z   = cherrypy.request.headers['z']
    img = mapnik.Image()
    img.background = self._mapnik_map.background

    if not x or not y or not z:
      error_msg = "Failed request:\n\tx: %s\n\ty: %s\n\tz: %s\n" % (x, y, z)
      cherrypy.reponse.headers["Status"] = "400"
      return error_msg
    else:
      # NOTE: Process request correctly
      x         = int(x)
      y         = int(y)
      z         = int(z)
      envelope  = self.merc.xyz_to_envelope(x,y,zoom)

      if self.envelope.intersects(envelope):
        self._mapnik_map.zoom_to_box(envelope)
        self._mapnik_map.buffer_size = self.buffer_size
        mapnik.render(self._mapnik_map, img)
        cherrypy.reponse.headers["Status"] = "200"

    return img.tostring('png256')

    def rpc_renderArea(self, minlat, minlon, maxlat, maxlon):
        """
        Renders a map for the given coordin
        """
        Map = None

        LandmassShapefile = 'cape/Interface/ne_110m_admin_0_countries.shp'

        merc = mapnik.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 [email protected] '
            '+no_defs +over')

        # long/lat in degrees, aka ESPG:4326 and "WGS 84" 
        longlat = mapnik.Projection('+proj=longlat +ellps=WGS84 +datum=WGS84 +no_defs')
        # can also be constructed as:
        #longlat = mapnik.Projection('+init=epsg:4326')

        im = mapnik.Image(self.mapsize)

        m = self.rendermap
        m.srs = merc.params()
        bbox = mapnik.Box2d(minlat, minlon, maxlat, maxlon)
        transform = mapnik.ProjTransform(longlat, merc)
        merc_bbox = transform.forward(bbox)

        m.zoom_to_box(merc_bbox)
        mapnik.render(m, im)
        Map = im.tostring('png')

        return (True, Map)

    def render_tile(self, x, y, z):
        # Calculate pixel positions of bottom-left & top-right
        p0 = (x * TILE_SIZE, (y + 1) * TILE_SIZE)
        p1 = ((x + 1) * TILE_SIZE, y * TILE_SIZE)

        # Convert to LatLong (EPSG:4326)
        l0 = self.tileproj.fromPixelToLL(p0, z)
        l1 = self.tileproj.fromPixelToLL(p1, z)

        # Convert to map projection (e.g. mercator co-ords EPSG:900913)
        c0 = self.prj.forward(mapnik.Coord(l0[0], l0[1]))
        c1 = self.prj.forward(mapnik.Coord(l1[0], l1[1]))

        # Bounding box for the tile
        if hasattr(mapnik, "mapnik_version") and mapnik.mapnik_version() >= 800:
            bbox = mapnik.Box2d(c0.x, c0.y, c1.x, c1.y)
        else:
            bbox = mapnik.Envelope(c0.x, c0.y, c1.x, c1.y)
        render_size = TILE_SIZE
        self.m.resize(render_size, render_size)
        self.m.zoom_to_box(bbox)
        self.m.buffer_size = 128

        # Render image with default Agg renderer
        im = mapnik.Image(render_size, render_size)
        mapnik.render(self.m, im)
        self.writer.write(x, y, z, im)

    def render(self, filename, tile_x, tile_y, zoom):
        """
        Render a single tile to a given filename.
        """
        print 'Rendering %s' % (filename)

        # Calculate pixel positions of bottom-left & top-right
        half_width = self.width / 2
        half_height = self.height / 2
        px0 = (tile_x * self.width, (tile_y + 1) * self.height)
        px1 = ((tile_x + 1) * self.width, tile_y * self.height)

        # Convert tile coords to LatLng
        ll0 = self.tile_projection.fromPixelToLL(px0, zoom);
        ll1 = self.tile_projection.fromPixelToLL(px1, zoom);
        
        # Convert LatLng to map coords
        c0 = self.map_projection.forward(mapnik2.Coord(ll0[0], ll0[1]))
        c1 = self.map_projection.forward(mapnik2.Coord(ll1[0], ll1[1]))

        # Create bounding box for the render
        bbox = mapnik2.Box2d(c0.x, c0.y, c1.x, c1.y)

        self.mapnik_map.zoom_to_box(bbox)
        self.mapnik_map.buffer_size = self.buffer_size 

        # Render image with default renderer
        image = mapnik2.Image(self.width, self.height)
        mapnik2.render(self.mapnik_map, image)
        image.save(filename, self.filetype)

    def get_one(self, tile):
        bbox = self.tilegrid.extent(tile.tilecoord, self.buffer)
        bbox2d = mapnik.Box2d(bbox[0], bbox[1], bbox[2], bbox[3])

        size = tile.tilecoord.n * self.tilegrid.tile_size + 2 * self.buffer
        self.mapnik.resize(size, size)
        self.mapnik.zoom_to_box(bbox2d)

        if self.output_format == "grid":
            grid = mapnik.Grid(self.tilegrid.tile_size, self.tilegrid.tile_size)
            for n, l in enumerate(self.mapnik.layers):
                if l.name in self.layers_fields:
                    mapnik.render_layer(self.mapnik, grid, layer=n, fields=self.layers_fields[l.name])

            encode = grid.encode("utf", resolution=self.resolution)
            if self.drop_empty_utfgrid and len(encode["data"].keys()) == 0:
                return None
            tile.data = dumps(encode)
        else:
            # Render image with default Agg renderer
            im = mapnik.Image(size, size)
            mapnik.render(self.mapnik, im)
            tile.data = im.tostring(self.output_format)

        return tile

    def drawTile_bbox(self,bbox,imgx,imgy,fname):
        """Call Mapnik to draw a map image for data in
        bounding box bbox.  The image size is imgx by imgy pixels, and
        the output filename is fname.

        29sep2009  GJ  ORIGINAL VERSION, based on generate_image.py
        06jan2010  GJ  Renamed to drawTile_bbox from drawTile
        """
        mapfile = str(self.preferences_list['mapfile'])
        map_uri = str(fname)
        print ("mapfile=%s" % mapfile)

        # png image
        m = mapnik.Map(imgx,imgy)
        mapnik.load_map(m,mapfile)
        m.zoom_to_box(bbox)
        im = mapnik.Image(imgx,imgy)

        if HAS_MAPNIK2:
            # We apply the scale factor to the map
            print 'using scale factors from mapnik2'
            scale_factor = float( self.preferences_list['dpi'] ) / 72
            print "Scale factor is: ", scale_factor, "================="
            mapnik.render(m, im, scale_factor)
        else:
            print 'NOT using scale_factors'
            mapnik.render(m, im)
            
        view = im.view(0,0,imgx,imgy) # x,y,width,height
        view.save(map_uri,'png')

    def render_tile(self, tile_uri, x, y, z):
        # Calculate pixel positions of bottom-left & top-right
        p0 = (x * 256, (y + 1) * 256)
        p1 = ((x + 1) * 256, y * 256)

        # Convert to LatLong (EPSG:4326)
        l0 = self.tileproj.fromPixelToLL(p0, z)
        l1 = self.tileproj.fromPixelToLL(p1, z)

        # Convert to map projection (e.g. mercator co-ords EPSG:900913)
        c0 = self.prj.forward(mapnik.Coord(l0[0], l0[1]))
        c1 = self.prj.forward(mapnik.Coord(l1[0], l1[1]))

        # Bounding box for the tile
        if hasattr(mapnik, "mapnik_version") and mapnik.mapnik_version() >= 800:
            bbox = mapnik.Box2d(c0.x, c0.y, c1.x, c1.y)
        else:
            bbox = mapnik.Envelope(c0.x, c0.y, c1.x, c1.y)
        render_size = 256
        self.m.resize(render_size, render_size)
        self.m.zoom_to_box(bbox)
        self.m.buffer_size = 128

        # Render image with default Agg renderer
        im = mapnik.Image(render_size, render_size)
        mapnik.render(self.m, im)

        # Ensure the tile isn't blank before saving
        if not im.tostring("png") == self.blankTileStr:
            im.save(tile_uri, "png256")
            # Return True if the tile was saved
            return True
        else:
            return False

 def get(self):
     mapfile = os.path.join(DATA_PATH, 'hazard', 'flood.shp')
     #mapfile = os.path.join(DATA_PATH, 'impact', 'impact.json')
     filename = os.path.join(DATA_PATH, 'pdf', 'report_map.pdf')
     filename2 = os.path.join(DATA_PATH, 'pdf', 'report_map.png')
     map = mapnik2.Map(600, 400)
     
     map.background = mapnik2.Color('steelblue')
     s = mapnik2.Style()
     r = mapnik2.Rule()
     polygon_symbolizer = mapnik2.PolygonSymbolizer(mapnik2.Color('#f2eff9'))
     r.symbols.append(polygon_symbolizer)
     line_symbolizer = mapnik2.LineSymbolizer(mapnik2.Color('rgb(50%,50%,50%)'),0.1)
     r.symbols.append(line_symbolizer)
     s.rules.append(r)
     map.append_style('My Style',s)
     ds = mapnik2.Shapefile(file=mapfile)
     layer = mapnik2.Layer('world')
     layer.datasource = ds
     layer.styles.append('My Style')
     map.layers.append(layer)
     map.zoom_all()
     mapnik2.render_to_file(map, filename2, 'png')
     
     #bbox = mapnik.Envelope(-180.0,-90.0,180.0,90.0)
     #map.zoom_to_box(bbox)
     surface = cairo.PDFSurface(filename, map.width, map.height)
     mapnik2.render(map, surface)
     surface.finish()
     
     with open(filename) as data:
         pdf = data.read()
         data.close()
         self.set_header("Content-Type", "application/pdf")
         self.write(pdf)

def test_raster_warping_does_not_overclip_source():
    lyrSrs = "+init=epsg:32630"
    mapSrs = '+proj=longlat +ellps=WGS84 +datum=WGS84 +no_defs'
    lyr = mapnik2.Layer('dataraster', lyrSrs)
    if 'gdal' in mapnik2.DatasourceCache.instance().plugin_names():
        lyr.datasource = mapnik2.Gdal(
            file = '../data/raster/dataraster.tif',
            band = 1,
            )
        sym = mapnik2.RasterSymbolizer()
        sym.colorizer = mapnik2.RasterColorizer(mapnik2.COLORIZER_DISCRETE, mapnik2.Color(255,255,0))
        rule = mapnik2.Rule()
        rule.symbols.append(sym)
        style = mapnik2.Style()
        style.rules.append(rule)
        _map = mapnik2.Map(256,256, mapSrs)
        _map.background=mapnik2.Color('white')
        _map.append_style('foo', style)
        lyr.styles.append('foo')
        _map.layers.append(lyr)
        _map.zoom_to_box(mapnik2.Box2d(3,42,4,43))
    
        im = mapnik2.Image(_map.width,_map.height)
        mapnik2.render(_map, im)
        # save a png somewhere so we can see it
        save_data('test_raster_warping_does_not_overclip_source.png',
                  im.tostring('png'))
        assert im.view(0,200,1,1).tostring()=='\xff\xff\x00\xff'

def test_raster_warping():
    lyrSrs = "+init=epsg:32630"
    mapSrs = '+proj=longlat +ellps=WGS84 +datum=WGS84 +no_defs'
    lyr = mapnik2.Layer('dataraster', lyrSrs)
    if 'gdal' in mapnik2.DatasourceCache.instance().plugin_names():
        lyr.datasource = mapnik2.Gdal(
            file = '../data/raster/dataraster.tif',
            band = 1,
            )
        sym = mapnik2.RasterSymbolizer()
        sym.colorizer = mapnik2.RasterColorizer(mapnik2.COLORIZER_DISCRETE, mapnik2.Color(255,255,0))
        rule = mapnik2.Rule()
        rule.symbols.append(sym)
        style = mapnik2.Style()
        style.rules.append(rule)
        _map = mapnik2.Map(256,256, mapSrs)
        _map.append_style('foo', style)
        lyr.styles.append('foo')
        _map.layers.append(lyr)
        prj_trans = mapnik2.ProjTransform(mapnik2.Projection(mapSrs),
                                          mapnik2.Projection(lyrSrs)) 
        _map.zoom_to_box(prj_trans.backward(lyr.envelope()))
    
        im = mapnik2.Image(_map.width,_map.height)
        mapnik2.render(_map, im)
        # save a png somewhere so we can see it
        save_data('test_raster_warping.png', im.tostring('png'))
        imdata = im.tostring()
        assert contains_word('\xff\xff\x00\xff', imdata)

def renderToPdf(envLL, filename, sizex, sizey):
    """Renders the specified Box2d and zoom level as a PDF"""
    basefilename = os.path.splitext(filename)[0]
    mergedpdf = None
    for mapname in MAPNIK_LAYERS:
        print 'Rendering', mapname
        # Render layer PDF.
        localfilename = basefilename + '_' + mapname + '.pdf';
        file = open(localfilename, 'wb')
        surface = cairo.PDFSurface(file.name, sizex, sizey) 
        envMerc = LLToMerc(envLL)
        map = mapnik.Map(sizex, sizey)
        mapnik.load_map(map, mapname + ".xml")
        map.zoom_to_box(envMerc)
        mapnik.render(map, surface)
        surface.finish()
        file.close()
        # Merge with master.
        if not mergedpdf:            
            mergedpdf = PdfFileWriter()
            localpdf = PdfFileReader(open(localfilename, "rb"))
            page = localpdf.getPage(0)
            mergedpdf.addPage(page)
        else:
            localpdf = PdfFileReader(open(localfilename, "rb"))
            page.mergePage(localpdf.getPage(0))
    output = open(filename, 'wb')
    mergedpdf.write(output)
    output.close()

    def generate_map_tile(self, m, filename, z, x, y):
        # Code taken from OSM generate_tiles.py
        proj = GoogleProjection()
        mprj = mapnik.Projection(m.srs)

        p0 = (x * 256, (y + 1) * 256)
        p1 = ((x + 1) * 256, y * 256)
        l0 = proj.fromPixelToLL(p0, z);
        l1 = proj.fromPixelToLL(p1, z);
        c0 = mprj.forward(mapnik.Coord(l0[0], l0[1]))
        c1 = mprj.forward(mapnik.Coord(l1[0], l1[1]))

        if hasattr(mapnik,'mapnik_version') and mapnik.mapnik_version() >= 800:
            bbox = mapnik.Box2d(c0.x, c0.y, c1.x, c1.y)
        else:
            bbox = mapnik.Envelope(c0.x, c0.y, c1.x, c1.y)

        m.resize(256, 256)
        m.zoom_to_box(bbox)

        im = mapnik.Image(256, 256)
        mapnik.render(m, im)
        # See https://github.com/mapnik/mapnik/wiki/OutputFormats for output
        # formats and special parameters. The default here is 32 bit PNG with 8
        # bit per component and alpha channel.
        if mapnik_version == 2:
            im.save(str(filename), "png32")
        else:
            im.save(str(filename), "png")

    def renderArea(self, width, height, srs, xmin, ymin, xmax, ymax, zoom):
        """
        """
        if self.mapnik is None:
            self.mapnik = mapnik.Map(0, 0)

            if exists(self.mapfile):
                mapnik.load_map(self.mapnik, str(self.mapfile))

            else:
                handle, filename = mkstemp()
                os.write(handle, urlopen(self.mapfile).read())
                os.close(handle)

                mapnik.load_map(self.mapnik, filename)
                os.unlink(filename)

        self.mapnik.width = width
        self.mapnik.height = height
        self.mapnik.zoom_to_box(mapnik.Envelope(xmin, ymin, xmax, ymax))

        img = mapnik.Image(width, height)
        mapnik.render(self.mapnik, img)

        img = Image.fromstring("RGBA", (width, height), img.tostring())

        return img

    def render_tile(self, tile_uri, x, y, z):
        # Calculate pixel positions of bottom-left & top-right
        p0 = (x * 256, (y + 1) * 256)
        p1 = ((x + 1) * 256, y * 256)

        # Convert to LatLong (EPSG:4326)
        l0 = self.tileproj.fromPixelToLL(p0, z);
        l1 = self.tileproj.fromPixelToLL(p1, z);

        # Convert to map projection (e.g. mercator co-ords EPSG:900913)
        c0 = self.prj.forward(mapnik.Coord(l0[0],l0[1]))
        c1 = self.prj.forward(mapnik.Coord(l1[0],l1[1]))

        # Bounding box for the tile
        if hasattr(mapnik,'mapnik_version') and mapnik.mapnik_version() >= 800:
            bbox = mapnik.Box2d(c0.x,c0.y, c1.x,c1.y)
        else:
            bbox = mapnik.Envelope(c0.x,c0.y, c1.x,c1.y)
        render_size = 256
        self.m.resize(render_size, render_size)
        self.m.zoom_to_box(bbox)
        if(self.m.buffer_size < 128):
            self.m.buffer_size = 128

        # Render image with default Agg renderer
        im = mapnik.Image(render_size, render_size)
        mapnik.render(self.m, im)
        im.save(tile_uri, 'png256')

 def render_dynamic(self, painter):
     if self.mapnik_map:
         w = painter.device().width()
         h = painter.device().height()
         # using canvas dims leads to shift in QGIS < 1.3...
         #w = self.canvas.width()
         #h = self.canvas.height()
         try:
             self.mapnik_map.resize(w,h)
         except:
             self.mapnik_map.width = w
             self.mapnik_map.height = h
         if self.qCanvas:
             can = self.qCanvas
         else:
             can = self.canvas
         try:
             e = can.extent()
         except:
             can = self.canvas
             e = can.extent()
         bbox = mapnik.Envelope(e.xMinimum(),e.yMinimum(),
                                e.xMaximum(),e.yMaximum())
         self.mapnik_map.zoom_to_box(bbox)
         im = mapnik.Image(w,h)
         mapnik.render(self.mapnik_map,im)
         if os.name == 'nt':
             qim = QImage()
             qim.loadFromData(QByteArray(im.tostring('png')))
             painter.drawImage(0,0,qim)
         else:
             qim = QImage(im.tostring(),w,h,QImage.Format_ARGB32)
             painter.drawImage(0,0,qim.rgbSwapped())
         can.refresh()