image_type render(mapnik::Map & map, double scale_factor, map_size const & tiles) const
{
mapnik::box2d<double> box = map.get_current_extent();
image_type image(map.width(), map.height());
map.resize(image.width() / tiles.width, image.height() / tiles.height);
double tile_box_width = box.width() / tiles.width;
double tile_box_height = box.height() / tiles.height;
for (std::size_t tile_y = 0; tile_y < tiles.height; tile_y++)
{
for (std::size_t tile_x = 0; tile_x < tiles.width; tile_x++)
{
mapnik::box2d<double> tile_box(
box.minx() + tile_x * tile_box_width,
box.miny() + tile_y * tile_box_height,
box.minx() + (tile_x + 1) * tile_box_width,
box.miny() + (tile_y + 1) * tile_box_height);
map.zoom_to_box(tile_box);
image_type tile(ren.render(map, scale_factor));
set_rectangle(tile, image, tile_x * tile.width(), (tiles.height - 1 - tile_y) * tile.height());
}
}
return image;
}
//------------------------------------------------------------------------------
void TileRenderer::RenderTile(std::string tile_uri, mapnik::Map m, int x, int y, int zoom, GoogleProjection tileproj, mapnik::projection prj, bool verbose, bool overrideTile, bool lockEnabled, std::string compositionLayerPath, std::string compositionMode, double compositionAlpha)
{
if(!overrideTile && FileSystem::FileExists(tile_uri))
{
return;
}
else
{
// Calculate pixel positions of bottom-left & top-right
ituple p0(x * 256, (y + 1) * 256);
ituple p1((x + 1) * 256, y * 256);
// Convert to LatLong (EPSG:4326)
dtuple l0 = tileproj.pixel2GeoCoord(p0, zoom);
dtuple l1 = tileproj.pixel2GeoCoord(p1, zoom);
// Convert to map projection (e.g. mercator co-ords EPSG:900913)
dtuple c0(l0.a,l0.b);
dtuple c1(l1.a,l1.b);
prj.forward(c0.a, c0.b);
prj.forward(c1.a, c1.b);
// Bounding box for the tile
#ifndef MAPNIK_2
mapnik::Envelope<double> bbox = mapnik::Envelope<double>(c0.a,c0.b,c1.a,c1.b);
m.resize(256,256);
m.zoomToBox(bbox);
#else
mapnik::box2d<double> bbox(c0.a,c0.b,c1.a,c1.b);
m.resize(256,256);
m.zoom_to_box(bbox);
#endif
m.set_buffer_size(128);
// Render image with default Agg renderer
#ifndef MAPNIK_2
mapnik::Image32 buf(m.getWidth(),m.getHeight());
mapnik::agg_renderer<mapnik::Image32> ren(m,buf);
#else
mapnik::image_32 buf(m.width(), m.height());
mapnik::agg_renderer<mapnik::image_32> ren(m,buf);
#endif
ren.apply();
if(lockEnabled)
{
int lockhandle = FileSystem::Lock(tile_uri);
#ifndef MAPNIK_2
Compose(compositionLayerPath, compositionMode, compositionAlpha, m.getWidth(),m.getHeight(),&buf, zoom, x,y);
mapnik::save_to_file<mapnik::ImageData32>(buf.data(),tile_uri,"png");
#else
Compose(compositionLayerPath, compositionMode, compositionAlpha, m.width(),m.height(),&buf, zoom, x,y);
mapnik::save_to_file<mapnik::image_data_32>(buf.data(),tile_uri,"png");
#endif
FileSystem::Unlock(tile_uri, lockhandle);
}
else
{
#ifndef MAPNIK_2
Compose(compositionLayerPath, compositionMode, compositionAlpha, m.getWidth(),m.getHeight(),&buf, zoom, x,y);
mapnik::save_to_file<mapnik::ImageData32>(buf.data(),tile_uri,"png");
#else
Compose(compositionLayerPath, compositionMode, compositionAlpha, m.width(),m.height(),&buf, zoom, x,y);
mapnik::save_to_file<mapnik::image_data_32>(buf.data(),tile_uri,"png");
#endif
}
}
}