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Performance improvement for get_joint_angles

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Grant Sanderson 2023-01-08 21:29:08 -05:00
parent 9e7cd1399d
commit 21051ce289
1 changed files with 35 additions and 20 deletions
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55
manimlib/mobject/types/vectorized_mobject.py
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@ -37,6 +37,7 @@ from manimlib.utils.space_ops import get_norm
from manimlib.utils.space_ops import get_unit_normal from manimlib.utils.space_ops import get_unit_normal
from manimlib.utils.space_ops import normalize_along_axis from manimlib.utils.space_ops import normalize_along_axis
from manimlib.utils.space_ops import z_to_vector from manimlib.utils.space_ops import z_to_vector
from manimlib.utils.simple_functions import arr_clip
from manimlib.shader_wrapper import ShaderWrapper from manimlib.shader_wrapper import ShaderWrapper
from typing import TYPE_CHECKING from typing import TYPE_CHECKING
@ -1028,45 +1029,59 @@ class VMobject(Mobject):
mob.needs_new_joint_angles = True mob.needs_new_joint_angles = True
return self return self
def get_joint_angles(self, result): def get_joint_angles(self, result=None):
""" """
Fills the array `result` with angle information for One can optionally pass in `result` as an array
each point which the answer will be read into.
""" """
points = self.get_points() points = self.get_points()
assert(len(result) == len(points)) if result is not None:
assert(len(result) == len(points))
else:
result = np.zeros(len(points))
if(len(points) == 0):
return result
# Unit tangent vectors # Unit tangent vectors
a0, h, a1 = points[0::3], points[1::3], points[2::3] a0, h, a1 = points[0::3], points[1::3], points[2::3]
a0_to_h = normalize_along_axis(h - a0, 1) a0_to_h = normalize_along_axis(h - a0, 1)
h_to_a1 = normalize_along_axis(a1 - h, 1) h_to_a1 = normalize_along_axis(a1 - h, 1)
def angles(vects1, vects2): vect_to_vert = np.zeros(points.shape)
angle = np.arccos(np.clip((vects1 * vects2).sum(1), -1, 1)) vect_from_vert = np.zeros(points.shape)
sgn = np.sign(cross2d(vects1, vects2))
return sgn * angle
# Angles at all handle points vect_to_vert[1::3] = a0_to_h
result[1::3] = angles(a0_to_h, h_to_a1) vect_from_vert[1::3] = h_to_a1
# Angles at first anchors vect_to_vert[0] = h_to_a1[-1]
to_a1 = np.vstack([h_to_a1[-1:], h_to_a1[:-1]]) vect_to_vert[3::3] = h_to_a1[:-1]
result[0::3] = angles(to_a1, a0_to_h) vect_from_vert[0::3] = a0_to_h
# Angles at second anchors vect_to_vert[2::3] = h_to_a1
from_a2 = np.vstack([a0_to_h[1:], a0_to_h[:1]]) vect_from_vert[2:-1:3] = a0_to_h[1:]
result[2::3] = angles(h_to_a1, from_a2) vect_from_vert[-1] = a0_to_h[0]
# Compute angles
dots = (vect_to_vert * vect_from_vert).sum(1)
angle = np.arccos(arr_clip(dots, -1, 1))
sgn = np.sign(cross2d(vect_to_vert, vect_from_vert))
result[:] = sgn * angle
# To communicate to the shader that a given anchor point # To communicate to the shader that a given anchor point
# sits at the end of a curve, we set its angle equal # sits at the end of a curve, we set its angle equal
# to something outside the range [-pi, pi]. # to something outside the range [-pi, pi].
# An arbitrary constant is used # An arbitrary constant is used
a0_matched = np.isclose(a0, np.vstack([a1[-1:], a1[:-1]])).all(1) mis_matches = (a0[1:] != a1[:-1]).any(1)
a1_matched = np.isclose(a1, np.vstack([a0[1:], a0[:1]])).all(1) ends_mismatch = (a1[-1] != a0[0]).any()
result[0::3][~a0_matched] = DISJOINT_CONST if ends_mismatch:
result[2::3][~a1_matched] = DISJOINT_CONST result[0] = DISJOINT_CONST
result[-1] = DISJOINT_CONST
result[3::3][mis_matches] = DISJOINT_CONST
result[2:-1:3][mis_matches] = DISJOINT_CONST
self.needs_new_joint_angles = False self.needs_new_joint_angles = False
return result
def triggers_refreshed_triangulation(func: Callable): def triggers_refreshed_triangulation(func: Callable):
@wraps(func) @wraps(func)