Files
Nominatim/test/bdd/utils/grid.py
2025-12-30 15:21:20 +01:00

73 lines
2.1 KiB
Python

# SPDX-License-Identifier: GPL-3.0-or-later
#
# This file is part of Nominatim. (https://nominatim.org)
#
# Copyright (C) 2025 by the Nominatim developer community.
# For a full list of authors see the git log.
"""
A grid describing node placement in an area.
Useful for visually describing geometries.
"""
import re
class Grid:
def __init__(self, table, step, origin):
if step is None:
step = 0.00001
if origin is None:
origin = (0.0, 0.0)
self.grid = {}
y = origin[1]
for line in table:
x = origin[0]
for pt_id in line:
if pt_id:
self.grid[pt_id] = (x, y)
x += step
y += step
def get(self, nodeid):
""" Get the coordinates for the given grid node.
"""
return self.grid.get(nodeid)
def parse_point(self, value):
""" Get the coordinates for either a grid node or a full coordinate.
"""
value = value.strip()
if ' ' in value:
return [float(v) for v in value.split(' ', 1)]
return self.grid.get(value)
def parse_line(self, value):
return [self.parse_point(p) for p in value.split(',')]
def geometry_to_wkt(self, value):
""" Parses the given value into a geometry and returns the WKT.
The value can either be a WKT already or a geometry shortcut
with coordinates or grid points.
"""
if re.fullmatch(r'([A-Z]+)\((.*)\)', value) is not None:
return value # already a WKT
# points
if ',' not in value:
x, y = self.parse_point(value)
return f"POINT({x} {y})"
# linestring
if '(' not in value:
coords = ','.join(' '.join(f"{p:.7f}" for p in pt)
for pt in self.parse_line(value))
return f"LINESTRING({coords})"
# simple polygons
coords = ','.join(' '.join(f"{p:.7f}" for p in pt)
for pt in self.parse_line(value[1:-1]))
return f"POLYGON(({coords}))"