def _bezier_guide_channel(self, start, outer_width, inner_width, length, p2, p3):
top_curve = CubicBezierCurve(
(start, outer_width), (start + p2[0] * length / 2., outer_width - p2[1] * inner_width),
(start + p3[0] * length / 2., inner_width + p3[1] * (outer_width - inner_width)),
(start + length / 2., inner_width))
bottom_curve = CubicBezierCurve((start + length / 2., inner_width),
(start + length / 2. + p2[0] * length / 2., inner_width + p2[1] * inner_width),
(start + length / 2. + p3[0] * length / 2.,
outer_width - p3[1] * (outer_width - inner_width)),
(start + length, outer_width))
return Polygon(
chain(zip(*top_curve.evaluate(np.linspace(0, 1, self._points_per_curve))), zip(*bottom_curve.evaluate(
np.linspace(0, 1, self._points_per_curve))), ([(length, 0), (0, 0)])))
def add_cubic_bezier_path(self, p0, p1, p2, p3, width=None, **kwargs):
"""
Add a cubic bezier path to the waveguide.
Coordinates are in the "waveguide tip coordinate system", so the first point will probably be p0 == (0, 0).
Note that your bezier curve undergoes the same restrictions as a parameterized path. Don't self-intersect it and
don't use small bend radii.
:param p0: 2 element tuple like coordinates
:param p1: 2 element tuple like coordinates
:param p2: 2 element tuple like coordinates
:param p3: 2 element tuple like coordinates
:param width: Width of the waveguide, as passed to :func:add_parameterized_path
:param kwargs: Optional keyword arguments, passed to :func:add_parameterized_path
:return: Changed waveguide
:rtype: Waveguide
"""
bezier_curve = CubicBezierCurve(p0, p1, p2, p3)
self.add_parameterized_path(path=bezier_curve.evaluate,
path_derivative=bezier_curve.evaluate_d1,
width=width,
path_function_supports_numpy=True,
**kwargs)
return self
def _bezier_guide_symm(self, start, width_1, width_2, length, p2, p3):
top_curve = CubicBezierCurve(
*[(start, width_1 / 2), (start + p2[0] * length, width_1 / 2 - p2[1] * width_2 / 2),
(start + p3[0] * length, width_1 / 2 - p3[1] * (width_1 / 2 - width_2 / 2)),
(start + length, width_2 / 2)])
bottom_curve = CubicBezierCurve(
*[(start, -width_1 / 2), (start + p2[0] * length, -width_1 / 2 + p2[1] * width_2 / 2),
(start + p3[0] * length, -width_1 / 2 + p3[1] * (width_1 / 2 - width_2 / 2)),
(start + length, -width_2 / 2)])
y_bottom = bottom_curve.evaluate(np.linspace(1, 0, self._points_per_curve))
y_top = top_curve.evaluate(np.linspace(0, 1, self._points_per_curve))
return Polygon(chain(zip(y_top[0], y_top[1]), zip(y_bottom[0], y_bottom[1])))