Source code for sertit.geometry

# -*- coding: utf-8 -*-
# Copyright 2024, SERTIT-ICube - France, https://sertit.unistra.fr/
# This file is part of sertit-utils project
#     https://github.com/sertit/sertit-utils
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
"""
Geometry tools

You can use this only if you have installed sertit[full] or sertit[vectors]
"""
import logging

import numpy as np
from shapely.errors import GeometryTypeError
from tqdm import tqdm

from sertit.types import AnyPolygonType

try:
    import geopandas as gpd
    from shapely import ops
    from shapely.geometry import Polygon, box
except ModuleNotFoundError as ex:
    raise ModuleNotFoundError(
        "Please install 'geopandas' to use the rasters package."
    ) from ex

from sertit import vectors
from sertit.logs import SU_NAME

LOGGER = logging.getLogger(SU_NAME)


[docs] def from_polygon_to_bounds(polygon: AnyPolygonType) -> (float, float, float, float): """ Convert a :code:`shapely.polygon` to its bounds, sorted as :code:`left, bottom, right, top`. .. code-block:: python >>> poly = Polygon(((0., 0.), (0., 1.), (1., 1.), (1., 0.), (0., 0.))) >>> from_polygon_to_bounds(poly) (0.0, 0.0, 1.0, 1.0) Args: polygon (MultiPolygon): polygon to convert Returns: (float, float, float, float): left, bottom, right, top """ left = polygon.bounds[0] # xmin bottom = polygon.bounds[1] # ymin right = polygon.bounds[2] # xmax top = polygon.bounds[3] # ymax assert left < right assert bottom < top return left, bottom, right, top
[docs] def from_bounds_to_polygon( left: float, bottom: float, right: float, top: float ) -> Polygon: """ Convert the bounds to a :code:`shapely.polygon`. .. code-block:: python >>> poly = from_bounds_to_polygon(0.0, 0.0, 1.0, 1.0) >>> print(poly) 'POLYGON ((1 0, 1 1, 0 1, 0 0, 1 0))' Args: left (float): Left coordinates bottom (float): Bottom coordinates right (float): Right coordinates top (float): Top coordinates Returns: Polygon: Polygon corresponding to the bounds """ return box(min(left, right), min(top, bottom), max(left, right), max(top, bottom))
[docs] def get_wider_exterior(vector: gpd.GeoDataFrame) -> gpd.GeoDataFrame: """ Get the wider exterior of a MultiPolygon as a Polygon Args: vector (gpd.GeoDataFrame): Polygon to simplify Returns: vector: gpd.GeoDataFrame: Wider exterior """ vector = vector.explode(index_parts=True) # Get the footprint max (discard small holes stored in other polygons) wider = vector[vector.area == np.max(vector.area)] # Only select the exterior of this footprint(sometimes some holes persist) if not wider.empty: poly = Polygon(list(wider.exterior.iat[0].coords)) wider = gpd.GeoDataFrame(geometry=[poly], crs=wider.crs) # Resets index as we only got one polygon left which should have index 0 wider.reset_index(inplace=True) return wider
[docs] def make_valid(gdf: gpd.GeoDataFrame, verbose=False) -> gpd.GeoDataFrame: """ Repair geometries from a dataframe. Args: gdf (gpd.GeoDataFrame): GeoDataFrame to repair verbose (bool): Verbose invalid geometries Returns: gpd.GeoDataFrame: Repaired geometries """ try: geos_logger = logging.getLogger("shapely.geos") previous_level = geos_logger.level if verbose: logging.debug("Invalid geometries:\n" f"\t{gdf[~gdf.is_valid]}") else: geos_logger.setLevel(logging.CRITICAL) # Discard self-intersection and null geometries from shapely.validation import make_valid gdf.geometry = gdf.geometry.apply(make_valid) if not verbose: geos_logger.setLevel(previous_level) except ImportError: import shapely LOGGER.warning( f"make_valid not available in shapely (version {shapely.__version__} < 1.8). " f"The obtained vector may be broken !" ) return gdf
[docs] def simplify_footprint( footprint: gpd.GeoDataFrame, resolution: float, max_nof_vertices: int = 50 ) -> gpd.GeoDataFrame: """ Simplify footprint. Set a number of maximum vertices and this function will try to simplify the footprint to have less than this number of vertices. The tolerance will grow to try to respect this number of vertices. This function will loop over a number of pixels of tolerence [1, 2, 4, 8, 16, 32, 64] (tolerance of gpd.simplify == resolution * tol_pix) If in the end, the number of vertices is still too high, a warning will be emitted. Args: footprint (gpd.GeoDataFrame): Footprint to be simplified resolution (float): Corresponding resolution max_nof_vertices (int): Maximum number of vertices of the wanted footprint Returns: gpd.GeoDataFrame: Simplified footprint """ # Number of pixels of tolerance tolerance = [1, 2, 4, 8, 16, 32, 64] # Process only if given footprint is too complex (too many vertices) def simplify_geom(value): nof_vertices = len(value.exterior.coords) if nof_vertices > max_nof_vertices: for tol in tolerance: # Simplify footprint value = value.simplify( tolerance=tol * resolution, preserve_topology=True ) # Check if OK nof_vertices = len(value.exterior.coords) if nof_vertices <= max_nof_vertices: break return value footprint = footprint.explode(index_parts=True) footprint.geometry = footprint.geometry.apply(simplify_geom) return footprint
[docs] def fill_polygon_holes( gpd_results: gpd.GeoDataFrame, threshold: float = None ) -> gpd.GeoDataFrame: """ Fill holes over a given threshold on the hole area (in meters) for all polygons of a GeoDataFrame. If the threshold is set to None, every hole is filled. Args: gpd_results (gpd.GeoDataFrame): Geodataframe filled whith drilled polygons threshold (float): Holes area threshold, in meters. If set to None, every hole is filled. Returns: gpd.GeoDataFrame: GeoDataFrame with filled holes """ def _fill_polygon(polygon: Polygon, threshold: float = None): """ Function used in apply in fill_polygon_holes """ if threshold is not None: if threshold > 0 and len(polygon.interiors) > 0: new_interiors = list(polygon.interiors) for interior in polygon.interiors: interior_poly = Polygon(np.array(interior.coords)) if interior_poly.area < threshold: new_interiors.remove(interior) return Polygon(polygon.exterior, new_interiors) else: return polygon else: return Polygon(polygon.exterior) # Ensure the geometries are valid gpd_results = make_valid(gpd_results) # Check if vector is projected, if not convert it with vectors.utm_crs(gpd_results) as utm_results: # Explode the multipolygons utm_results = utm_results.explode(index_parts=False) # Keep only the exterior tqdm.pandas(desc="Processing objects") utm_results.geometry = utm_results.geometry.progress_apply( _fill_polygon, args=(threshold,) ) # Dissolve and explode to remove polygons in polygons utm_results = utm_results.dissolve() gpd_results = utm_results.explode(index_parts=False) # Write back to file return gpd_results
[docs] def split(polygons: gpd.GeoDataFrame, splitter: gpd.GeoDataFrame): """ Split polygons with polygons Args: polygons (gpd.GeoDataFrame): Polygons to split splitter (gpd.GeoDataFrame): Splitter to split the polygons Returns: gpd.GeoDataFrame: Split GeoDataFrame """ out = polygons.geometry for _, split in splitter.iterrows(): # Compute the boundary of the splitter polygon (to get a LineString) boundary = split.geometry.boundary # Explode to prevent FeatureCollections try: # LineStrings out = out.map(lambda geom: ops.split(geom, boundary).geoms).explode() except GeometryTypeError: # MultiLineStrings for line in boundary.geoms: out = out.map(lambda geom: ops.split(geom, line).geoms).explode() return gpd.GeoDataFrame(geometry=out.explode(), crs=polygons.crs)