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Add TracingTail

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This commit is contained in:
Grant Sanderson 2021-08-21 10:36:59 -07:00
parent 7b4199c674
commit a35dd5a3cb
1 changed files with 49 additions and 15 deletions
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64
manimlib/mobject/changing.py
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@ -1,4 +1,10 @@
from manimlib.constants import * import numpy as np
from manimlib.constants import BLUE_D
from manimlib.constants import BLUE_B
from manimlib.constants import BLUE_E
from manimlib.constants import GREY_BROWN
from manimlib.constants import WHITE
from manimlib.mobject.mobject import Mobject
from manimlib.mobject.types.vectorized_mobject import VMobject from manimlib.mobject.types.vectorized_mobject import VMobject
from manimlib.mobject.types.vectorized_mobject import VGroup from manimlib.mobject.types.vectorized_mobject import VGroup
from manimlib.utils.rate_functions import smooth from manimlib.utils.rate_functions import smooth
@ -75,24 +81,52 @@ class TracedPath(VMobject):
"stroke_width": 2, "stroke_width": 2,
"stroke_color": WHITE, "stroke_color": WHITE,
"min_distance_to_new_point": 0.1, "min_distance_to_new_point": 0.1,
"time_traced": np.inf,
"fill_opacity": 0,
"sparseness": 1,
} }
def __init__(self, traced_point_func, **kwargs): def __init__(self, traced_point_func, **kwargs):
super().__init__(**kwargs) super().__init__(**kwargs)
self.traced_point_func = traced_point_func self.traced_point_func = traced_point_func
self.add_updater(lambda m: m.update_path()) self.time = 0
self.times = []
self.traced_points = []
self.add_updater(lambda m, dt: m.update_path(dt))
def update_path(self): def update_path(self, dt):
new_point = self.traced_point_func() point = np.array(self.traced_point_func())
if not self.has_points(): tps = self.traced_points
self.start_new_path(new_point) times = self.times
self.add_line_to(new_point)
if len(tps) == 0:
tps.append(point)
times.append(self.time)
if get_norm(point - tps[-1]) >= self.min_distance_to_new_point:
times.append(self.time)
tps.append(point)
# Cut off tail
while times and times[0] < self.time - self.time_traced:
times = times[1:]
tps = tps[1:]
if tps:
self.set_points_as_corners(tps[::self.sparseness])
self.time += dt
class TracingTail(TracedPath):
CONFIG = {
"stroke_width": (0, 3),
"stroke_opacity": (0, 1),
"stroke_color": WHITE,
"time_traced": 1.0,
"min_distance_to_new_point": 0,
"sparseness": 3,
}
def __init__(self, mobject_or_func, **kwargs):
if isinstance(mobject_or_func, Mobject):
func = mobject_or_func.get_center
else: else:
# Set the end to be the new point func = mobject_or_func
self.get_points()[-1] = new_point super().__init__(func, **kwargs)
# Second to last point
nppcc = self.n_points_per_curve
dist = get_norm(new_point - self.get_points()[-nppcc])
if dist >= self.min_distance_to_new_point:
self.add_line_to(new_point)