masque/masque/shapes/ellipse.py

162 lines
5.0 KiB
Python

from typing import List
import math
import numpy
from numpy import pi
from . import Shape, Polygon, normalized_shape_tuple, DEFAULT_POLY_NUM_POINTS
from .. import PatternError
from ..utils import is_scalar, rotation_matrix_2d, vector2
__author__ = 'Jan Petykiewicz'
class Ellipse(Shape):
"""
An ellipse, which has a position, two radii, and a rotation.
The rotation gives the angle from x-axis, counterclockwise, to the first (x) radius.
"""
_radii = None # type: numpy.ndarray
_rotation = 0.0 # type: float
# Defaults for to_polygons
poly_num_points = DEFAULT_POLY_NUM_POINTS # type: int
poly_max_arclen = None # type: float
# radius properties
@property
def radii(self) -> numpy.ndarray:
"""
Return the radii [rx, ry]
:return: [rx, ry]
"""
return self._radii
@radii.setter
def radii(self, val: vector2):
val = numpy.array(val).flatten()
if not val.size == 2:
raise PatternError('Radii must have length 2')
if not val.min() >= 0:
raise PatternError('Radii must be non-negative')
self._radii = val
@property
def radius_x(self) -> float:
return self.radii[0]
@radius_x.setter
def radius_x(self, val: float):
if not val >= 0:
raise PatternError('Radius must be non-negative')
self.radii[0] = val
@property
def radius_y(self) -> float:
return self.radii[1]
@radius_y.setter
def radius_y(self, val: float):
if not val >= 0:
raise PatternError('Radius must be non-negative')
self.radii[1] = val
# Rotation property
@property
def rotation(self) -> float:
"""
Rotation of rx from the x axis. Uses the interval [0, pi) in radians (counterclockwise
is positive)
:return: counterclockwise rotation in radians
"""
return self._rotation
@rotation.setter
def rotation(self, val: float):
if not is_scalar(val):
raise PatternError('Rotation must be a scalar')
self._rotation = val % pi
def __init__(self,
radii: vector2,
rotation: float=0,
poly_num_points: int=DEFAULT_POLY_NUM_POINTS,
poly_max_arclen: float=None,
offset: vector2=(0.0, 0.0),
layer: int=0,
dose: float=1.0):
self.offset = offset
self.layer = layer
self.dose = dose
self.radii = radii
self.rotation = rotation
self.poly_num_points = poly_num_points
self.poly_max_arclen = poly_max_arclen
def to_polygons(self,
poly_num_points: int=None,
poly_max_arclen: float=None
) -> List[Polygon]:
if poly_num_points is None:
poly_num_points = self.poly_num_points
if poly_max_arclen is None:
poly_max_arclen = self.poly_max_arclen
if (poly_num_points is None) and (poly_max_arclen is None):
raise PatternError('Number of points and arclength left unspecified'
' (default was also overridden)')
r0, r1 = self.radii
# Approximate perimeter
# Ramanujan, S., "Modular Equations and Approximations to ,"
# Quart. J. Pure. Appl. Math., vol. 45 (1913-1914), pp. 350-372
h = ((r1 - r0) / (r1 + r0)) ** 2
perimeter = pi * (r1 + r0) * (1 + 3 * h / (10 + math.sqrt(4 - 3 * h)))
n = []
if poly_num_points is not None:
n += [poly_num_points]
if poly_max_arclen is not None:
n += [perimeter / poly_max_arclen]
thetas = numpy.linspace(2 * pi, 0, max(n), endpoint=False)
sin_th, cos_th = (numpy.sin(thetas), numpy.cos(thetas))
xs = r0 * cos_th
ys = r1 * sin_th
xys = numpy.vstack((xs, ys)).T
poly = Polygon(xys, dose=self.dose, layer=self.layer, offset=self.offset)
poly.rotate(self.rotation)
return [poly]
def get_bounds(self) -> numpy.ndarray:
rot_radii = numpy.dot(rotation_matrix_2d(self.rotation), self.radii)
return numpy.vstack((self.offset - rot_radii[0],
self.offset + rot_radii[1]))
def rotate(self, theta: float) -> 'Ellipse':
self.rotation += theta
return self
def scale_by(self, c: float) -> 'Ellipse':
self.radii *= c
return self
def normalized_form(self, norm_value: float) -> normalized_shape_tuple:
if self.radius_x < self.radius_y:
radii = self.radii / self.radius_x
scale = self.radius_x
angle = self.rotation
else:
radii = self.radii[::-1] / self.radius_y
scale = self.radius_y
angle = (self.rotation + pi / 2) % pi
return (type(self), radii, self.layer), \
(self.offset, scale/norm_value, angle, self.dose), \
lambda: Ellipse(radii=radii*norm_value, layer=self.layer)