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Update VShowPassingFlash for new path mode

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This commit is contained in:
Grant Sanderson
2023-01-11 16:40:40 -08:00
parent 032a8fd030
commit d3a40eb1ac
1 changed files with 22 additions and 26 deletions
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48
manimlib/animation/indication.py
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@ -205,25 +205,26 @@ class VShowPassingFlash(Animation):
self.time_width = time_width
self.taper_width = taper_width
super().__init__(vmobject, remover=remover, **kwargs)
self.mobject = vmobject
def taper_kernel(self, x):
if x < self.taper_width:
return x
elif x > 1 - self.taper_width:
return 1.0 - x
return 1.0
def begin(self) -> None:
self.mobject.align_stroke_width_data_to_points()
# Compute an array of stroke widths for each submobject
# which tapers out at either end
self.submob_to_anchor_widths = dict()
self.submob_to_widths = dict()
for sm in self.mobject.get_family():
original_widths = sm.get_stroke_widths()
anchor_widths = np.array([*original_widths[0::3], original_widths[-1]])
def taper_kernel(x):
if x < self.taper_width:
return x
elif x > 1 - self.taper_width:
return 1.0 - x
return 1.0
taper_array = list(map(taper_kernel, np.linspace(0, 1, len(anchor_widths))))
self.submob_to_anchor_widths[hash(sm)] = anchor_widths * taper_array
widths = sm.get_stroke_widths()
self.submob_to_widths[hash(sm)] = np.array([
width * self.taper_kernel(x)
for width, x in zip(widths, np.linspace(0, 1, len(widths)))
])
super().begin()
def interpolate_submobject(
@ -232,26 +233,21 @@ class VShowPassingFlash(Animation):
starting_sumobject: None,
alpha: float
) -> None:
anchor_widths = self.submob_to_anchor_widths[hash(submobject)]
widths = self.submob_to_widths[hash(submobject)]
# Create a gaussian such that 3 sigmas out on either side
# will equals time_width
tw = self.time_width
sigma = tw / 6
mu = interpolate(-tw / 2, 1 + tw / 2, alpha)
def gauss_kernel(x):
if abs(x - mu) > 3 * sigma:
return 0
z = (x - mu) / sigma
return math.exp(-0.5 * z * z)
xs = np.linspace(0, 1, len(widths))
zs = (xs - mu) / sigma
gaussian = np.exp(-0.5 * zs * zs)
gaussian[abs(xs - mu) > 3 * sigma] = 0
submobject.set_stroke(width=widths * gaussian)
kernel_array = list(map(gauss_kernel, np.linspace(0, 1, len(anchor_widths))))
scaled_widths = anchor_widths * kernel_array
new_widths = np.zeros(submobject.get_num_points())
new_widths[0::3] = scaled_widths[:-1]
new_widths[2::3] = scaled_widths[1:]
new_widths[1::3] = (new_widths[0::3] + new_widths[2::3]) / 2
submobject.set_stroke(width=new_widths)
def finish(self) -> None:
super().finish()