clipping 3.1.0

Polygons clipping based on algorithm by F. Martinez et al.

clipping

In what follows python is an alias for python3.5 or pypy3.5 or any later version (python3.6, pypy3.6 and so on).

Installation

Install the latest pip & setuptools packages versions

python -m pip install --upgrade pip setuptools

User

Download and install the latest stable version from PyPI repository

python -m pip install --upgrade clipping

Developer

Download the latest version from GitHub repository

git clone https://github.com/lycantropos/clipping.git
cd clipping

Install dependencies

python -m pip install -r requirements.txt

Install

python setup.py install

Usage

>>> from ground.base import get_context
>>> context = get_context()
>>> EMPTY = context.empty
>>> Mix = context.mix_cls
>>> Multipoint = context.multipoint_cls
>>> Multisegment = context.multisegment_cls
>>> Point = context.point_cls
>>> Segment = context.segment_cls
>>> left_edge = Segment(Point(0, 0), Point(0, 1))
>>> right_edge = Segment(Point(1, 0), Point(1, 1))
>>> bottom_edge = Segment(Point(0, 0), Point(1, 0))
>>> top_edge = Segment(Point(0, 1), Point(1, 1))
>>> main_diagonal = Segment(Point(0, 0), Point(1, 1))
>>> trident = Multisegment([left_edge, main_diagonal, bottom_edge])
>>> square_edges = Multisegment([bottom_edge, right_edge, top_edge, left_edge])
>>> from clipping.planar import intersect_multisegments
>>> (intersect_multisegments(trident, square_edges)
...  == intersect_multisegments(square_edges, trident)
...  == Multisegment([left_edge, bottom_edge]))
True
>>> from clipping.planar import complete_intersect_multisegments
>>> (complete_intersect_multisegments(trident, square_edges)
...  == complete_intersect_multisegments(square_edges, trident)
...  == Mix(Multipoint([Point(1, 1)]), Multisegment([left_edge, bottom_edge]),
...         EMPTY))
True
>>> from clipping.planar import unite_multisegments
>>> (unite_multisegments(trident, square_edges)
...  == unite_multisegments(square_edges, trident)
...  == Multisegment([left_edge, bottom_edge, main_diagonal, top_edge,
...                   right_edge]))
True
>>> from clipping.planar import subtract_multisegments
>>> subtract_multisegments(trident, square_edges) == main_diagonal
True
>>> (subtract_multisegments(square_edges, trident)
...  == Multisegment([top_edge, right_edge]))
True
>>> from clipping.planar import symmetric_subtract_multisegments
>>> (symmetric_subtract_multisegments(trident, square_edges)
...  == symmetric_subtract_multisegments(square_edges, trident)
...  == Multisegment([main_diagonal, top_edge, right_edge]))
True
>>> Contour = context.contour_cls
>>> Multipolygon = context.multipolygon_cls
>>> Polygon = context.polygon_cls
>>> first_square = Contour([Point(0, 0), Point(1, 0), Point(1, 1),
...                         Point(0, 1)])
>>> second_square = Contour([Point(1, 0), Point(2, 0), Point(2, 1),
...                          Point(1, 1)])
>>> third_square = Contour([Point(1, 1), Point(2, 1), Point(2, 2),
...                         Point(1, 2)])
>>> fourth_square = Contour([Point(0, 1), Point(1, 1), Point(1, 2),
...                          Point(0, 2)])
>>> from clipping.planar import intersect_multipolygons
>>> (intersect_multipolygons(Multipolygon([Polygon(first_square, []),
...                                        Polygon(third_square, [])]),
...                          Multipolygon([Polygon(second_square, []),
...                                        Polygon(fourth_square, [])]))
...  is EMPTY)
True
>>> (intersect_multipolygons(Multipolygon([Polygon(first_square, []),
...                                        Polygon(third_square, [])]),
...                          Multipolygon([Polygon(first_square, []),
...                                        Polygon(third_square, [])]))
...  == Multipolygon([Polygon(first_square, []), Polygon(third_square, [])]))
True
>>> from clipping.planar import complete_intersect_multipolygons
>>> (complete_intersect_multipolygons(
...      Multipolygon([Polygon(first_square, []), Polygon(third_square, [])]),
...      Multipolygon([Polygon(second_square, []),
...                    Polygon(fourth_square, [])]))
...  == Multisegment([Segment(Point(0, 1), Point(1, 1)),
...                   Segment(Point(1, 0), Point(1, 1)),
...                   Segment(Point(1, 1), Point(2, 1)),
...                   Segment(Point(1, 1), Point(1, 2))]))
True
>>> (complete_intersect_multipolygons(
...      Multipolygon([Polygon(first_square, []), Polygon(third_square, [])]),
...      Multipolygon([Polygon(first_square, []), Polygon(third_square, [])]))
...  == Multipolygon([Polygon(first_square, []), Polygon(third_square, [])]))
True
>>> from clipping.planar import unite_multipolygons
>>> (unite_multipolygons(Multipolygon([Polygon(first_square, []),
...                                    Polygon(third_square, [])]),
...                      Multipolygon([Polygon(second_square, []),
...                                    Polygon(fourth_square, [])]))
...  == Polygon(Contour([Point(0, 0), Point(2, 0), Point(2, 2), Point(0, 2)]),
...             []))
True
>>> (unite_multipolygons(Multipolygon([Polygon(first_square, []),
...                                    Polygon(third_square, [])]),
...                      Multipolygon([Polygon(first_square, []),
...                                    Polygon(third_square, [])]))
...  == Multipolygon([Polygon(first_square, []), Polygon(third_square, [])]))
True
>>> from clipping.planar import subtract_multipolygons
>>> (subtract_multipolygons(Multipolygon([Polygon(first_square, []),
...                                       Polygon(third_square, [])]),
...                         Multipolygon([Polygon(first_square, []),
...                                       Polygon(third_square, [])]))
...  is EMPTY)
True
>>> (subtract_multipolygons(Multipolygon([Polygon(first_square, []),
...                                       Polygon(third_square, [])]),
...                         Multipolygon([Polygon(second_square, []),
...                                       Polygon(fourth_square, [])]))
...  == Multipolygon([Polygon(first_square, []), Polygon(third_square, [])]))
True
>>> from clipping.planar import symmetric_subtract_multipolygons
>>> (symmetric_subtract_multipolygons(
...      Multipolygon([Polygon(first_square, []), Polygon(third_square, [])]),
...      Multipolygon([Polygon(first_square, []), Polygon(third_square, [])]))
...  is EMPTY)
True
>>> (symmetric_subtract_multipolygons(
...      Multipolygon([Polygon(first_square, []), Polygon(third_square, [])]),
...      Multipolygon([Polygon(second_square, []),
...                    Polygon(fourth_square, [])]))
...  == Polygon(Contour([Point(0, 0), Point(2, 0), Point(2, 2), Point(0, 2)]),
...             []))
True

Development

Bumping version

Preparation

Install bump2version.

Pre-release

Choose which version number category to bump following semver specification.

Test bumping version

bump2version --dry-run --verbose $CATEGORY

where $CATEGORY is the target version number category name, possible values are patch/minor/major.

Bump version

bump2version --verbose $CATEGORY

This will set version to major.minor.patch-alpha.

Release

Test bumping version

bump2version --dry-run --verbose release

Bump version

bump2version --verbose release

This will set version to major.minor.patch.

Running tests

Install dependencies

python -m pip install -r requirements-tests.txt

Plain

pytest

Inside Docker container:

• with CPython

  docker-compose --file docker-compose.cpython.yml up
  

• with PyPy

  docker-compose --file docker-compose.pypy.yml up
  

Bash script (e.g. can be used in Git hooks):

• with CPython

  ./run-tests.sh
  

  or

  ./run-tests.sh cpython
  

• with PyPy

  ./run-tests.sh pypy
  

PowerShell script (e.g. can be used in Git hooks):

• with CPython

  .\run-tests.ps1
  

  or

  .\run-tests.ps1 cpython
  

• with PyPy

  .\run-tests.ps1 pypy