"""
Box class for geometric operations.
This class is used to speed up the evaluation of point containment
"""
from __future__ import annotations
from typing import Union
from ..tools import Is, To
from .point import Point2D, cartesian
[docs]
class Box:
"""
Box class, which speeds up the evaluation of ``__contains__``
in classes like ``Segment``, ``JordanCurve`` and ``SimpleShape``.
Since it's faster to evaluate if a point is in a rectangle (this box),
we avoid some computations like projecting the point on a curve and
verifying if the distance is big enough to consider whether the point
is the object
"""
dx = 1e-6
dy = 1e-6
def __init__(self, lowpt: Point2D, toppt: Point2D):
self.lowpt = To.point(lowpt)
self.toppt = To.point(toppt)
def __eq__(self, other: Box) -> Box:
if not Is.instance(other, Box):
raise TypeError
return self.lowpt == other.lowpt and self.toppt == other.toppt
def __str__(self) -> str: # pragma: no cover
return f"Box with vertices {self.lowpt} and {self.toppt}"
def __bool__(self) -> bool:
return True
def __contains__(self, point: Point2D) -> bool:
point = To.point(point)
if point[0] < self.lowpt[0] - self.dx:
return False
if point[1] < self.lowpt[1] - self.dy:
return False
if self.toppt[0] + self.dx < point[0]:
return False
return not self.toppt[1] + self.dy < point[1]
def __or__(self, other: Box) -> Box:
xmin = min(self.lowpt[0], other.lowpt[0])
ymin = min(self.lowpt[1], other.lowpt[1])
xmax = max(self.toppt[0], other.toppt[0])
ymax = max(self.toppt[1], other.toppt[1])
return Box(cartesian(xmin, ymin), cartesian(xmax, ymax))
def __ror__(self, other) -> Box:
return self
def __and__(self, other: Box) -> Union[Box, None]:
xmin = max(self.lowpt[0], other.lowpt[0])
xmax = min(self.toppt[0], other.toppt[0])
if xmax < xmin:
return None
ymin = max(self.lowpt[1], other.lowpt[1])
ymax = min(self.toppt[1], other.toppt[1])
if ymax < ymin:
return None
return Box(cartesian(xmin, ymin), cartesian(xmax, ymax))