def viewing_rays(self, screen):
lower_angle, upper_angle = self.viewing_angles(screen)
projected_RIGHT = self.project(
RIGHT) / get_norm(self.project(RIGHT))
lower_ray = rotate_vector(
projected_RIGHT, lower_angle, axis=self.projection_direction())
upper_ray = rotate_vector(
projected_RIGHT, upper_angle, axis=self.projection_direction())
return lower_ray, upper_ray
def viewing_rays(self, screen):
lower_angle, upper_angle = self.viewing_angles(screen)
projected_RIGHT = self.project(
RIGHT) / get_norm(self.project(RIGHT))
lower_ray = rotate_vector(
projected_RIGHT, lower_angle, axis=self.projection_direction())
upper_ray = rotate_vector(
projected_RIGHT, upper_angle, axis=self.projection_direction())
return lower_ray, upper_ray
def calc_centers_by_radii(r1, r2, r3, init_angle=0):
if init_angle is None:
init_angle = TAU * np.random.random_sample()
r12 = r1 + r2
r23 = r2 + r3
r13 = r1 + r3
cos_theta = (r12**2 + r13**2 - r23**2) / (2 * r12 * r13)
theta = math.acos(cos_theta)
p1 = ORIGIN
p2 = p1 + rotate_vector(RIGHT, init_angle) * r12
p3 = p1 + rotate_vector(RIGHT * r13, init_angle + theta)
return p1, p2, p3
def get_arc_center(self):
"""
Looks at the normals to the first two
anchors, and finds their intersection points
"""
# First two anchors and handles
a1, h, a2 = self.get_points()[:3]
# Tangent vectors
t1 = h - a1
t2 = h - a2
# Normals
n1 = rotate_vector(t1, TAU / 4)
n2 = rotate_vector(t2, TAU / 4)
return find_intersection(a1, n1, a2, n2)
def generate_points(self):
start_angle = np.pi / 2 + self.arc_angle / 2
end_angle = np.pi / 2 - self.arc_angle / 2
self.add(Arc(
start_angle=start_angle,
angle=-self.arc_angle
))
tick_angle_range = np.linspace(start_angle, end_angle, self.num_ticks)
for index, angle in enumerate(tick_angle_range):
vect = rotate_vector(RIGHT, angle)
tick = Line((1 - self.tick_length) * vect, vect)
label = TexMobject(str(10 * index))
label.set_height(self.tick_length)
label.shift((1 + self.tick_length) * vect)
self.add(tick, label)
needle = Polygon(
LEFT, UP, RIGHT,
stroke_width=0,
fill_opacity=1,
fill_color=self.needle_color
)
needle.stretch_to_fit_width(self.needle_width)
needle.stretch_to_fit_height(self.needle_height)
needle.rotate(start_angle - np.pi / 2, about_point=ORIGIN)
self.add(needle)
self.needle = needle
self.center_offset = self.get_center()
def set_points_by_ends(self, start, end, buff=0, path_arc=0):
vect = end - start
dist = get_norm(vect)
if np.isclose(dist, 0):
self.set_points_as_corners([start, end])
return self
if path_arc:
neg = path_arc < 0
if neg:
path_arc = -path_arc
start, end = end, start
radius = (dist / 2) / math.sin(path_arc / 2)
alpha = (PI - path_arc) / 2
center = start + radius * normalize(
rotate_vector(end - start, alpha))
raw_arc_points = Arc.create_quadratic_bezier_points(
angle=path_arc - 2 * buff / radius,
start_angle=angle_of_vector(start - center) + buff / radius,
)
if neg:
raw_arc_points = raw_arc_points[::-1]
self.set_points(center + radius * raw_arc_points)
else:
if buff > 0 and dist > 0:
start = start + vect * (buff / dist)
end = end - vect * (buff / dist)
self.set_points_as_corners([start, end])
return self
def add_smooth_curve_to(self, *points):
"""
If two points are passed in, the first is intepretted
as a handle, the second as an anchor
"""
if len(points) == 1:
handle2 = None
new_anchor = points[0]
elif len(points) == 2:
handle2, new_anchor = points
else:
name = sys._getframe(0).f_code.co_name
raise Exception("Only call {} with 1 or 2 points".format(name))
if self.has_new_path_started():
self.add_line_to(new_anchor)
else:
self.throw_error_if_no_points()
last_h2, last_a2 = self.points[-2:]
last_tangent = (last_a2 - last_h2)
handle1 = last_a2 + last_tangent
if handle2 is None:
to_anchor_vect = new_anchor - last_a2
new_tangent = rotate_vector(last_tangent,
PI,
axis=to_anchor_vect)
handle2 = new_anchor - new_tangent
self.append_points([last_a2, handle1, handle2, new_anchor])
return self
def init_points(self):
start_angle = np.pi / 2 + self.arc_angle / 2
end_angle = np.pi / 2 - self.arc_angle / 2
self.add(Arc(start_angle=start_angle, angle=-self.arc_angle))
tick_angle_range = np.linspace(start_angle, end_angle, self.num_ticks)
for index, angle in enumerate(tick_angle_range):
vect = rotate_vector(RIGHT, angle)
tick = Line((1 - self.tick_length) * vect, vect)
label = TexMobject(str(10 * index))
label.set_height(self.tick_length)
label.shift((1 + self.tick_length) * vect)
self.add(tick, label)
needle = Polygon(LEFT,
UP,
RIGHT,
stroke_width=0,
fill_opacity=1,
fill_color=self.needle_color)
needle.stretch_to_fit_width(self.needle_width)
needle.stretch_to_fit_height(self.needle_height)
needle.rotate(start_angle - np.pi / 2, about_point=ORIGIN)
self.add(needle)
self.needle = needle
self.center_offset = self.get_center()
def add_smooth_curve_to(self, *points):
"""
If two points are passed in, the first is intepretted
as a handle, the second as an anchor
"""
if len(points) == 1:
handle2 = None
new_anchor = points[0]
elif len(points) == 2:
handle2, new_anchor = points
else:
name = sys._getframe(0).f_code.co_name
raise Exception("Only call {} with 1 or 2 points".format(name))
if self.has_new_path_started():
self.add_line_to(new_anchor)
else:
self.throw_error_if_no_points()
last_h2, last_a2 = self.points[-2:]
last_tangent = (last_a2 - last_h2)
handle1 = last_a2 + last_tangent
if handle2 is None:
to_anchor_vect = new_anchor - last_a2
new_tangent = rotate_vector(
last_tangent, PI, axis=to_anchor_vect
)
handle2 = new_anchor - new_tangent
self.append_points([
last_a2, handle1, handle2, new_anchor
])
return self
def get_graph_label(self,
graph,
label="f(x)",
x=None,
direction=RIGHT,
buff=MED_SMALL_BUFF,
color=None):
if isinstance(label, str):
label = Tex(label)
if color is None:
label.match_color(graph)
if x is None:
# Searching from the right, find a point
# whose y value is in bounds
max_y = FRAME_Y_RADIUS - label.get_height()
max_x = FRAME_X_RADIUS - label.get_width()
for x0 in np.arange(*self.x_range)[::-1]:
pt = self.i2gp(x0, graph)
if abs(pt[0]) < max_x and abs(pt[1]) < max_y:
x = x0
break
if x is None:
x = self.x_range[1]
point = self.input_to_graph_point(x, graph)
angle = self.angle_of_tangent(x, graph)
normal = rotate_vector(RIGHT, angle + 90 * DEGREES)
if normal[1] < 0:
normal *= -1
label.next_to(point, normal, buff=buff)
label.shift_onto_screen()
return label
def __init__(self, n=6, **kwargs):
digest_config(self, kwargs, locals())
if self.start_angle is None:
# 0 for odd, 90 for even
self.start_angle = (n % 2) * 90 * DEGREES
start_vect = rotate_vector(RIGHT, self.start_angle)
vertices = compass_directions(n, start_vect)
super().__init__(*vertices, **kwargs)
def __init__(self, n=6, **kwargs):
digest_config(self, kwargs, locals())
if self.start_angle is None:
if n % 2 == 0:
self.start_angle = 0
else:
self.start_angle = 90 * DEGREES
start_vect = rotate_vector(RIGHT, self.start_angle)
vertices = compass_directions(n, start_vect)
Polygon.__init__(self, *vertices, **kwargs)
def __init__(self, n=6, **kwargs):
digest_config(self, kwargs, locals())
if self.start_angle is None:
if n % 2 == 0:
self.start_angle = 0
else:
self.start_angle = 90 * DEGREES
start_vect = rotate_vector(RIGHT, self.start_angle)
vertices = compass_directions(n, start_vect)
Polygon.__init__(self, *vertices, **kwargs)
def get_arc_center(self):
"""
Looks at the normals to the first two
anchors, and finds their intersection points
"""
# First two anchors and handles
a1, h1, h2, a2 = self.points[:4]
# Tangent vectors
t1 = h1 - a1
t2 = h2 - a2
# Normals
n1 = rotate_vector(t1, TAU / 4)
n2 = rotate_vector(t2, TAU / 4)
try:
return line_intersection(
line1=(a1, a1 + n1),
line2=(a2, a2 + n2),
)
except Exception:
warnings.warn("Can't find Arc center, using ORIGIN instead")
return np.array(ORIGIN)
def get_arc_center(self):
"""
Looks at the normals to the first two
anchors, and finds their intersection points
"""
# First two anchors and handles
a1, h1, h2, a2 = self.points[:4]
# Tangent vectors
t1 = h1 - a1
t2 = h2 - a2
# Normals
n1 = rotate_vector(t1, TAU / 4)
n2 = rotate_vector(t2, TAU / 4)
try:
return line_intersection(
line1=(a1, a1 + n1),
line2=(a2, a2 + n2),
)
except Exception:
warnings.warn("Can't find Arc center, using ORIGIN instead")
return np.array(ORIGIN)
def __init__(self, n=6, *args, **kwargs):
self.args_name = \
["mobject_or_point", "radius", "start_angle", "element", "normal_vector"]
self.args = \
[ORIGIN, 1, None, "point", "OUT"]
self.mobject_or_point, self.radius, self.start_angle, self.element, self.normal_vector = \
generate_args(self, args, self.args)
kwargs = merge_config_kwargs(self, kwargs, self.args_name)
self.mobject_or_point = Location(self.mobject_or_point)
if self.element == "point":
if self.start_angle is None:
if n % 2 == 0:
self.start_angle = 0
else:
self.start_angle = 90 * DEGREES
start_vect = rotate_vector(self.radius*RIGHT, self.start_angle)
vertices = np.add(compass_directions(n, start_vect),
np.repeat([self.mobject_or_point], n, axis=0))
GeomPolygon.__init__(self, *vertices, **kwargs)
def __init__(self, n=6, **kwargs):
#### EULERTOUR_INIT_START ####
if not hasattr(self, "args"):
self.args = serialize_args([])
if not hasattr(self, "config"):
self.config = serialize_config({
'n': n,
**kwargs,
})
#### EULERTOUR_INIT_START ####
digest_config(self, kwargs, locals())
if self.start_angle is None:
if n % 2 == 0:
self.start_angle = 0
else:
self.start_angle = 90 * DEGREES
start_vect = rotate_vector(RIGHT, self.start_angle)
vertices = compass_directions(n, start_vect)
Polygon.__init__(self, *vertices, **kwargs)
#### EULERTOUR_INIT_END ####
register_mobject(self)
def fractalification_iteration(vmobject,
dimension=1.05,
num_inserted_anchors_range=list(range(1, 4))):
num_points = vmobject.get_num_points()
if num_points > 0:
# original_anchors = vmobject.get_anchors()
original_anchors = [
vmobject.point_from_proportion(x)
for x in np.linspace(0, 1 - 1. / num_points, num_points)
]
new_anchors = []
for p1, p2, in zip(original_anchors, original_anchors[1:]):
num_inserts = random.choice(num_inserted_anchors_range)
inserted_points = [
interpolate(p1, p2, alpha)
for alpha in np.linspace(0, 1, num_inserts + 2)[1:-1]
]
mass_scaling_factor = 1. / (num_inserts + 1)
length_scaling_factor = mass_scaling_factor**(1. / dimension)
target_length = get_norm(p1 - p2) * length_scaling_factor
curr_length = get_norm(p1 - p2) * mass_scaling_factor
# offset^2 + curr_length^2 = target_length^2
offset_len = np.sqrt(target_length**2 - curr_length**2)
unit_vect = (p1 - p2) / get_norm(p1 - p2)
offset_unit_vect = rotate_vector(unit_vect, np.pi / 2)
inserted_points = [
point + u * offset_len * offset_unit_vect
for u, point in zip(it.cycle([-1, 1]), inserted_points)
]
new_anchors += [p1] + inserted_points
new_anchors.append(original_anchors[-1])
vmobject.set_points_as_corners(new_anchors)
vmobject.set_submobjects([
fractalification_iteration(submob, dimension,
num_inserted_anchors_range)
for submob in vmobject.submobjects
])
return vmobject
def fractalification_iteration(vmobject, dimension=1.05, num_inserted_anchors_range=list(range(1, 4))):
num_points = vmobject.get_num_points()
if num_points > 0:
# original_anchors = vmobject.get_anchors()
original_anchors = [
vmobject.point_from_proportion(x)
for x in np.linspace(0, 1 - 1. / num_points, num_points)
]
new_anchors = []
for p1, p2, in zip(original_anchors, original_anchors[1:]):
num_inserts = random.choice(num_inserted_anchors_range)
inserted_points = [
interpolate(p1, p2, alpha)
for alpha in np.linspace(0, 1, num_inserts + 2)[1:-1]
]
mass_scaling_factor = 1. / (num_inserts + 1)
length_scaling_factor = mass_scaling_factor**(1. / dimension)
target_length = get_norm(p1 - p2) * length_scaling_factor
curr_length = get_norm(p1 - p2) * mass_scaling_factor
# offset^2 + curr_length^2 = target_length^2
offset_len = np.sqrt(target_length**2 - curr_length**2)
unit_vect = (p1 - p2) / get_norm(p1 - p2)
offset_unit_vect = rotate_vector(unit_vect, np.pi / 2)
inserted_points = [
point + u * offset_len * offset_unit_vect
for u, point in zip(it.cycle([-1, 1]), inserted_points)
]
new_anchors += [p1] + inserted_points
new_anchors.append(original_anchors[-1])
vmobject.set_points_as_corners(new_anchors)
vmobject.submobjects = [
fractalification_iteration(
submob, dimension, num_inserted_anchors_range)
for submob in vmobject.submobjects
]
return vmobject
def __init__(self, n=3, **kwargs):
digest_config(self, kwargs, locals())
start_vect = rotate_vector(RIGHT, self.start_angle)
vertices = compass_directions(n, start_vect)
Polygon.__init__(self, *vertices, **kwargs)
def move_to(self, point_or_mobject):
vect = rotate_vector(UP + LEFT, self.orientation_line.get_angle())
self.next_to(point_or_mobject, vect, buff=0)
return self
def move_to(self, point_or_mobject):
vect = rotate_vector(
UP + LEFT, self.orientation_line.get_angle()
)
self.next_to(point_or_mobject, vect, buff=0)
return self
def set_points_by_ends(self, start, end, buff=0, path_arc=0):
# Find the right tip length and thickness
vect = end - start
length = max(get_norm(vect), 1e-8)
thickness = self.thickness
w_ratio = fdiv(self.max_width_to_length_ratio, fdiv(thickness, length))
if w_ratio < 1:
thickness *= w_ratio
tip_width = self.tip_width_ratio * thickness
tip_length = tip_width / (2 * np.tan(self.tip_angle / 2))
t_ratio = fdiv(self.max_tip_length_to_length_ratio,
fdiv(tip_length, length))
if t_ratio < 1:
tip_length *= t_ratio
tip_width *= t_ratio
# Find points for the stem
if path_arc == 0:
points1 = (length - tip_length) * np.array(
[RIGHT, 0.5 * RIGHT, ORIGIN])
points1 += thickness * UP / 2
points2 = points1[::-1] + thickness * DOWN
else:
# Solve for radius so that the tip-to-tail length matches |end - start|
a = 2 * (1 - np.cos(path_arc))
b = -2 * tip_length * np.sin(path_arc)
c = tip_length**2 - length**2
R = (-b + np.sqrt(b**2 - 4 * a * c)) / (2 * a)
# Find arc points
points1 = Arc.create_quadratic_bezier_points(path_arc)
points2 = np.array(points1[::-1])
points1 *= (R + thickness / 2)
points2 *= (R - thickness / 2)
if path_arc < 0:
tip_length *= -1
rot_T = rotation_matrix_transpose(PI / 2 - path_arc, OUT)
for points in points1, points2:
points[:] = np.dot(points, rot_T)
points += R * DOWN
self.set_points(points1)
# Tip
self.add_line_to(tip_width * UP / 2)
self.add_line_to(tip_length * LEFT)
self.tip_index = len(self.get_points()) - 1
self.add_line_to(tip_width * DOWN / 2)
self.add_line_to(points2[0])
# Close it out
self.append_points(points2)
self.add_line_to(points1[0])
if length > 0:
# Final correction
super().scale(length / self.get_length())
self.rotate(angle_of_vector(vect) - self.get_angle())
self.rotate(
PI / 2 - np.arccos(normalize(vect)[2]),
axis=rotate_vector(self.get_unit_vector(), -PI / 2),
)
self.shift(start - self.get_start())
self.refresh_triangulation()
