def _create_grid(self, canvas):
"""
Create a new Grid object for the given MapCanvas.
Args:
canvas (MapCanvas): Map Canvas (see _create_map_canvas).
Return a new Grid object.
"""
# Prepare the grid SHP
map_grid = Grid(canvas.get_actual_bounding_box(), canvas.get_actual_scale(), self.rc.i18n.isrtl())
grid_shape = map_grid.generate_shape_file(
os.path.join(self.tmpdir, 'grid.shp'))
# Add the grid SHP to the map
canvas.add_shape_file(grid_shape,
self.rc.stylesheet.grid_line_color,
self.rc.stylesheet.grid_line_alpha,
self.rc.stylesheet.grid_line_width)
return map_grid
def __init__(self, db, rc, tmpdir, dpi, file_prefix):
Renderer.__init__(self, db, rc, tmpdir, dpi)
self._grid_legend_margin_pt = \
min(Renderer.GRID_LEGEND_MARGIN_RATIO * self.paper_width_pt,
Renderer.GRID_LEGEND_MARGIN_RATIO * self.paper_height_pt)
# Compute the usable area per page
self._usable_area_width_pt = (self.paper_width_pt -
(2 * Renderer.PRINT_SAFE_MARGIN_PT))
self._usable_area_height_pt = (self.paper_height_pt -
(2 * Renderer.PRINT_SAFE_MARGIN_PT))
scale_denom = Renderer.DEFAULT_SCALE
# the mapnik scale depends on the latitude. However we are
# always using Mapnik conversion functions (lat,lon <->
# mercator_meters) so we don't need to take into account
# latitude in following computations
# by convention, mapnik uses 90 ppi whereas cairo uses 72 ppi
scale_denom *= float(72) / 90
GRAYED_MARGIN_MM = 10
OVERLAP_MARGIN_MM = 20
# Debug: show original bounding box as JS code
# print self.rc.bounding_box.as_javascript("original", "#00ff00")
# Convert the original Bounding box into Mercator meters
self._proj = mapnik.Projection(coords._MAPNIK_PROJECTION)
orig_envelope = self._project_envelope(self.rc.bounding_box)
# Extend the bounding box to take into account the lost outter
# margin
off_x = orig_envelope.minx - (GRAYED_MARGIN_MM * scale_denom) / 1000
off_y = orig_envelope.miny - (GRAYED_MARGIN_MM * scale_denom) / 1000
width = orig_envelope.width() + (2 * GRAYED_MARGIN_MM * scale_denom) / 1000
height = orig_envelope.height() + (2 * GRAYED_MARGIN_MM * scale_denom) / 1000
# Calculate the total width and height of paper needed to
# render the geographical area at the current scale.
total_width_pt = commons.convert_mm_to_pt(float(width) * 1000 / scale_denom)
total_height_pt = commons.convert_mm_to_pt(float(height) * 1000 / scale_denom)
self.grayed_margin_pt = commons.convert_mm_to_pt(GRAYED_MARGIN_MM)
overlap_margin_pt = commons.convert_mm_to_pt(OVERLAP_MARGIN_MM)
# Calculate the number of pages needed in both directions
if total_width_pt < self._usable_area_width_pt:
nb_pages_width = 1
else:
nb_pages_width = \
(float(total_width_pt - self._usable_area_width_pt) / \
(self._usable_area_width_pt - overlap_margin_pt)) + 1
if total_height_pt < self._usable_area_height_pt:
nb_pages_height = 1
else:
nb_pages_height = \
(float(total_height_pt - self._usable_area_height_pt) / \
(self._usable_area_height_pt - overlap_margin_pt)) + 1
# Round up the number of pages needed so that we have integer
# number of pages
self.nb_pages_width = int(math.ceil(nb_pages_width))
self.nb_pages_height = int(math.ceil(nb_pages_height))
# Calculate the entire paper area available
total_width_pt_after_extension = self._usable_area_width_pt + \
(self._usable_area_width_pt - overlap_margin_pt) * (self.nb_pages_width - 1)
total_height_pt_after_extension = self._usable_area_height_pt + \
(self._usable_area_height_pt - overlap_margin_pt) * (self.nb_pages_height - 1)
# Convert this paper area available in the number of Mercator
# meters that can be rendered on the map
total_width_merc = \
commons.convert_pt_to_mm(total_width_pt_after_extension) * scale_denom / 1000
total_height_merc = \
commons.convert_pt_to_mm(total_height_pt_after_extension) * scale_denom / 1000
# Extend the geographical boundaries so that we completely
# fill the available paper size. We are careful to extend the
# boundaries evenly on all directions (so the center of the
# previous boundaries remain the same as the new one)
off_x -= (total_width_merc - width) / 2
width = total_width_merc
off_y -= (total_height_merc - height) / 2
height = total_height_merc
# Calculate what is the final global bounding box that we will render
envelope = mapnik.Box2d(off_x, off_y, off_x + width, off_y + height)
self._geo_bbox = self._inverse_envelope(envelope)
# Debug: show transformed bounding box as JS code
# print self._geo_bbox.as_javascript("extended", "#0f0f0f")
# Convert the usable area on each sheet of paper into the
# amount of Mercator meters we can render in this area.
usable_area_merc_m_width = commons.convert_pt_to_mm(self._usable_area_width_pt) * scale_denom / 1000
usable_area_merc_m_height = commons.convert_pt_to_mm(self._usable_area_height_pt) * scale_denom / 1000
grayed_margin_merc_m = (GRAYED_MARGIN_MM * scale_denom) / 1000
overlap_margin_merc_m = (OVERLAP_MARGIN_MM * scale_denom) / 1000
# Calculate all the bounding boxes that correspond to the
# geographical area that will be rendered on each sheet of
# paper.
area_polygon = shapely.wkt.loads(self.rc.polygon_wkt)
bboxes = []
self.page_disposition, map_number = {}, 0
for j in reversed(range(0, self.nb_pages_height)):
col = self.nb_pages_height - j - 1
self.page_disposition[col] = []
for i in range(0, self.nb_pages_width):
cur_x = off_x + i * (usable_area_merc_m_width - overlap_margin_merc_m)
cur_y = off_y + j * (usable_area_merc_m_height - overlap_margin_merc_m)
envelope = mapnik.Box2d(cur_x, cur_y,
cur_x+usable_area_merc_m_width,
cur_y+usable_area_merc_m_height)
envelope_inner = mapnik.Box2d(cur_x + grayed_margin_merc_m,
cur_y + grayed_margin_merc_m,
cur_x + usable_area_merc_m_width - grayed_margin_merc_m,
cur_y + usable_area_merc_m_height - grayed_margin_merc_m)
inner_bb = self._inverse_envelope(envelope_inner)
if not area_polygon.disjoint(shapely.wkt.loads(
inner_bb.as_wkt())):
self.page_disposition[col].append(map_number)
map_number += 1
bboxes.append((self._inverse_envelope(envelope),
inner_bb))
else:
self.page_disposition[col].append(None)
# Debug: show per-page bounding boxes as JS code
# for i, (bb, bb_inner) in enumerate(bboxes):
# print bb.as_javascript(name="p%d" % i)
self.pages = []
# Create an overview map
overview_bb = self._geo_bbox.create_expanded(0.001, 0.001)
# Create the overview grid
self.overview_grid = OverviewGrid(overview_bb,
[bb_inner for bb, bb_inner in bboxes], self.rc.i18n.isrtl())
grid_shape = self.overview_grid.generate_shape_file(
os.path.join(self.tmpdir, 'grid_overview.shp'))
# Create a canvas for the overview page
self.overview_canvas = MapCanvas(self.rc.stylesheet,
overview_bb, self._usable_area_width_pt,
self._usable_area_height_pt, dpi,
extend_bbox_to_ratio=True)
# Create the gray shape around the overview map
exterior = shapely.wkt.loads(self.overview_canvas.get_actual_bounding_box()\
.as_wkt())
interior = shapely.wkt.loads(self.rc.polygon_wkt)
shade_wkt = exterior.difference(interior).wkt
shade = maplib.shapes.PolyShapeFile(self.rc.bounding_box,
os.path.join(self.tmpdir, 'shape_overview.shp'),
'shade-overview')
shade.add_shade_from_wkt(shade_wkt)
self.overview_canvas.add_shape_file(shade)
self.overview_canvas.add_shape_file(grid_shape,
self.rc.stylesheet.grid_line_color, 1,
self.rc.stylesheet.grid_line_width)
self.overview_canvas.render()
# Create the map canvas for each page
indexes = []
for i, (bb, bb_inner) in enumerate(bboxes):
# Create the gray shape around the map
exterior = shapely.wkt.loads(bb.as_wkt())
interior = shapely.wkt.loads(bb_inner.as_wkt())
shade_wkt = exterior.difference(interior).wkt
shade = maplib.shapes.PolyShapeFile(
bb, os.path.join(self.tmpdir, 'shade%d.shp' % i),
'shade%d' % i)
shade.add_shade_from_wkt(shade_wkt)
# Create the contour shade
# Area to keep visible
interior_contour = shapely.wkt.loads(self.rc.polygon_wkt)
# Determine the shade WKT
shade_contour_wkt = interior.difference(interior_contour).wkt
# Prepare the shade SHP
shade_contour = maplib.shapes.PolyShapeFile(bb,
os.path.join(self.tmpdir, 'shade_contour%d.shp' % i),
'shade_contour%d' % i)
shade_contour.add_shade_from_wkt(shade_contour_wkt)
# Create one canvas for the current page
map_canvas = MapCanvas(self.rc.stylesheet,
bb, self._usable_area_width_pt,
self._usable_area_height_pt, dpi,
extend_bbox_to_ratio=False)
# Create the grid
map_grid = Grid(bb_inner, map_canvas.get_actual_scale(), self.rc.i18n.isrtl())
grid_shape = map_grid.generate_shape_file(
os.path.join(self.tmpdir, 'grid%d.shp' % i))
map_canvas.add_shape_file(shade)
map_canvas.add_shape_file(shade_contour,
self.rc.stylesheet.shade_color_2,
self.rc.stylesheet.shade_alpha_2)
map_canvas.add_shape_file(grid_shape,
self.rc.stylesheet.grid_line_color,
self.rc.stylesheet.grid_line_alpha,
self.rc.stylesheet.grid_line_width)
map_canvas.render()
self.pages.append((map_canvas, map_grid))
# Create the index for the current page
inside_contour_wkt = interior_contour.intersection(interior).wkt
index = StreetIndex(self.db,
inside_contour_wkt,
self.rc.i18n, page_number=(i + 4))
index.apply_grid(map_grid)
indexes.append(index)
# Merge all indexes
self.index_categories = self._merge_page_indexes(indexes)
# Prepare the small map for the front page
self._front_page_map = self._prepare_front_page_map(dpi)
