Example #1
0
    def downloads_for(self, tile):
        tiles = set()
        # if the tile scale is greater than 20x the SRTM scale, then there's no
        # point in including SRTM, it'll be far too fine to make a difference.
        # SRTM is 1 arc second.
        if tile.max_resolution() > 20 * 1.0 / 3600:
            return tiles

        # buffer by 0.01 degrees (36px) to grab neighbouring tiles and ensure
        # that there aren't any boundary artefacts.
        tile_bbox = tile.latlon_bbox().buffer(0.01)

        tile_index = self._ensure_tile_index()

        for t in index.intersections(tile_index, tile_bbox):
            tiles.add(t)

        return tiles
Example #2
0
    def downloads_for(self, tile):
        tiles = set()
        # if the tile scale is greater than 20x the NED scale, then there's no
        # point in including NED, it'll be far too fine to make a difference.
        # NED13 is 1/3rd arc second.
        if tile.max_resolution() > 20 * 1.0 / (3600 * 3):
            return tiles

        # buffer by 0.0075 degrees (81px) to grab neighbouring tiles and ensure
        # some overlap to take care of boundary issues.
        tile_bbox = tile.latlon_bbox().buffer(0.0075)

        tile_index = self._ensure_tile_index()

        for t in index.intersections(tile_index, tile_bbox):
            tiles.add(t)

        return tiles
Example #3
0
    def downloads_for(self, tile):
        tiles = set()
        # if the tile scale is greater than 20x the NED scale, then there's no
        # point in including NED, it'll be far too fine to make a difference.
        # NED13 is 1/3rd arc second.
        if tile.max_resolution() > 20 * 1.0 / (3600 * 3):
            return tiles

        # buffer by 0.0075 degrees (81px) to grab neighbouring tiles and ensure
        # some overlap to take care of boundary issues.
        tile_bbox = tile.latlon_bbox().buffer(0.0075)

        tile_index = self._ensure_tile_index()

        for t in index.intersections(tile_index, tile_bbox):
            tiles.add(t)

        return tiles
Example #4
0
    def downloads_for(self, tile):
        tiles = set()
        # if the tile scale is greater than 20x the SRTM scale, then there's no
        # point in including SRTM, it'll be far too fine to make a difference.
        # SRTM is 1 arc second.
        if tile.max_resolution() > 20 * 1.0 / 3600:
            return tiles

        # buffer by 0.01 degrees (36px) to grab neighbouring tiles and ensure
        # that there aren't any boundary artefacts.
        tile_bbox = tile.latlon_bbox().buffer(0.01)

        tile_index = self._ensure_tile_index()

        for t in index.intersections(tile_index, tile_bbox):
            tiles.add(t)

        return tiles