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https://github.com/3b1b/manim.git
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Up to RotationMatrix in quat3d
This commit is contained in:
Grant Sanderson
parent
45d3806b86
commit
731a41c1e1
1 changed files with 704 additions and 14 deletions
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@ -15,18 +15,56 @@ class QuaternionLabel(VGroup):
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def __init__(self, quat, **kwargs):
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VGroup.__init__(self, **kwargs)
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dkwargs = dict(self.decimal_config)
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self.add(DecimalNumber(quat[0], color=W_COLOR, **dkwargs))
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decimals = VGroup()
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decimals.add(DecimalNumber(quat[0], color=W_COLOR, **dkwargs))
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dkwargs["include_sign"] = True
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self.add(
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decimals.add(
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DecimalNumber(quat[1], color=I_COLOR, **dkwargs),
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TexMobject("i"),
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DecimalNumber(quat[2], color=J_COLOR, **dkwargs),
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TexMobject("j"),
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DecimalNumber(quat[3], color=K_COLOR, **dkwargs),
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TexMobject("k"),
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)
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self.add(
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decimals[0],
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decimals[1], TexMobject("i"),
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decimals[2], TexMobject("j"),
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decimals[3], TexMobject("k"),
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)
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self.arrange_submobjects(RIGHT, buff=SMALL_BUFF)
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self.decimals = decimals
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def set_value(self, quat):
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for decimal, coord in zip(self.decimals, quat):
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decimal.set_value(coord)
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return self
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class RandyPrism(Cube):
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CONFIG = {
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"height": 0.25,
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"width": 1,
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"depth": 1.2,
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"fill_color": BLUE_D,
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"fill_opacity": 0.9,
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"stroke_color": WHITE,
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"stroke_width": 1,
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}
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def __init__(self, **kwargs):
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Cube.__init__(self, **kwargs)
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self.set_height(1)
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randy = Randolph(mode="pondering")
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randy.set_height(0.8)
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randy.rotate(TAU / 4, RIGHT)
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randy.shift(0.7 * DOWN)
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randy.set_shade_in_3d(True, z_index_as_group=True)
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self.randy = randy
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self.add(randy)
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self.set_height(self.height, stretch=True)
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self.set_width(self.width, stretch=True)
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self.set_depth(self.depth, stretch=True)
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self.center()
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# Scenes
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@ -138,15 +176,667 @@ class WhoCares(TeacherStudentsScene):
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RemovePiCreatureBubble(self.students[1]),
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self.teacher.change, "raise_right_hand"
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)
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self.play(
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LaggedStart(
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FadeInFromDown, quotes,
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run_time=3
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),
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self.get_student_changes(*3 * ["pondering"], look_at_arg=quotes)
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)
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self.wait(2)
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# self.play(
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# LaggedStart(
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# FadeInFromDown, quotes,
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# run_time=3
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# ),
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# self.get_student_changes(*3 * ["pondering"], look_at_arg=quotes)
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# )
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# self.wait(2)
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# Show HN
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# # Show HN
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# hn_quote = quotes[1]
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# hn_context = TextMobject("news.ycombinator.com/item?id=17933908")
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# hn_context.scale(0.7)
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# hn_context.to_corner(UL)
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# vr_headsets = VGroup()
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# for pi in self.students:
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# vr_headset = SVGMobject("VR_headset")
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# vr_headset.set_fill(LIGHT_GREY, opacity=0.9)
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# vr_headset.set_width(pi.eyes.get_width() + 0.3)
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# vr_headset.move_to(pi.eyes)
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# vr_headsets.add(vr_headset)
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# self.play(
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# hn_quote.scale, 2, {"about_edge": DL},
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# FadeOutAndShift(quotes[0], 5 * UP),
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# FadeOutAndShift(quotes[2], UR),
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# FadeOutAndShift(quotes[3], RIGHT),
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# FadeInFromDown(hn_context),
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# )
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# hn_rect = Rectangle(
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# height=0.1 * hn_quote.get_height(),
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# width=0.6 * hn_quote.get_width(),
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# color=RED
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# )
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# hn_rect.move_to(hn_quote, UL)
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# hn_rect.shift(0.225 * RIGHT + 0.75 * DOWN)
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# self.play(
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# ShowCreation(hn_rect),
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# self.get_student_changes(
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# "erm", "thinking", "confused",
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# look_at_arg=hn_quote,
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# )
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# )
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# self.add_foreground_mobjects(vr_headsets)
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# self.play(
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# LaggedStart(
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# FadeInFrom, vr_headsets,
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# lambda m: (m, UP),
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# ),
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# self.get_student_changes(
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# *3 * ["sick"],
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# look_at_arg=hn_quote,
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# run_time=3
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# )
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# )
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# self.wait(3)
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# Show Twitter
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t_quote = quotes[0]
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# t_quote.next_to(FRAME_WIDTH * LEFT / 2 + FRAME_WIDTH * UP / 2, UR)
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# t_quote.set_opacity(0)
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# self.play(
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# FadeOutAndShift(hn_quote, 4 * LEFT),
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# FadeOutAndShift(hn_rect, 4 * LEFT),
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# FadeOutAndShift(hn_context, UP),
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# FadeOut(vr_headsets),
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# t_quote.set_opacity, 1,
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# t_quote.scale, 2,
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# t_quote.to_corner, UL,
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# )
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# self.remove_foreground_mobjects(vr_headsets)
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t_quote.fade(1)
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t_quote.to_corner(UL)
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self.play(
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self.get_student_changes(*3 * ["pondering"], look_at_arg=quotes),
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t_quote.set_opacity, 1,
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t_quote.scale, 2,
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t_quote.to_corner, UL,
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)
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self.wait(2)
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self.change_student_modes(
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"pondering", "happy", "tease",
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look_at_arg=t_quote
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)
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self.wait(2)
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self.play(FadeOut(t_quote))
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self.wait(5)
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class ShowSeveralQuaternionRotations(SpecialThreeDScene):
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CONFIG = {
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"quaternions": [
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[0, 1, 0, 0],
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[1, 0, 0, 0],
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[1, 0, 1, 0],
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[1, 1, 1, -1],
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[0, -1, 2, 1],
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[1, 0, 0, -1],
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[1, -1, 0, 0],
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[1, -1, 1, 0],
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[1, -1, 1, -1],
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[1, 0, 0, 0],
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],
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"start_phi": 70 * DEGREES,
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"start_theta": -140 * DEGREES,
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}
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def construct(self):
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self.add_q_tracker()
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self.setup_labels()
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self.setup_camera_position()
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self.add_prism()
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self.add_axes()
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self.apply_quaternions()
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def add_q_tracker(self):
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self.q_tracker = QuaternionTracker()
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self.q_tracker.add_updater(lambda m: m.normalize())
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self.add(self.q_tracker)
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def setup_labels(self):
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left_q_label = QuaternionLabel([1, 0, 0, 0])
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right_q_label = QuaternionLabel([1, 0, 0, 0])
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for label in left_q_label, right_q_label:
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lp, rp = TexMobject("()")
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lp.next_to(label, LEFT, SMALL_BUFF)
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rp.next_to(label, RIGHT, SMALL_BUFF)
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label.add(lp, rp)
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point_label = TexMobject(
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*"(xi+yj+zk)",
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tex_to_color_map={
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"i": I_COLOR,
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"j": J_COLOR,
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"k": K_COLOR,
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}
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)
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left_q_label.next_to(point_label, LEFT)
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right_q_label.next_to(point_label, RIGHT)
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group = VGroup(left_q_label, point_label, right_q_label)
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group.arrange_submobjects(RIGHT)
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group.set_width(FRAME_WIDTH - 1)
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group.to_edge(UP)
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self.add_fixed_in_frame_mobjects(BackgroundRectangle(group))
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for label, text in zip(group, ["$q$", "Some 3d point", "$q^{-1}$"]):
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brace = Brace(label, DOWN)
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text_mob = TextMobject(text)
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if text_mob.get_width() > brace.get_width():
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text_mob.match_width(brace)
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text_mob.next_to(brace, DOWN, buff=SMALL_BUFF)
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text_mob.add_background_rectangle()
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label.add(brace, text_mob)
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self.add_fixed_in_frame_mobjects(*group)
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left_q_label.add_updater(
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lambda m: m.set_value(self.q_tracker.get_value())
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)
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left_q_label.add_updater(lambda m: self.add_fixed_in_frame_mobjects(m))
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right_q_label.add_updater(
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lambda m: m.set_value(quaternion_conjugate(
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self.q_tracker.get_value()
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))
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)
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right_q_label.add_updater(lambda m: self.add_fixed_in_frame_mobjects(m))
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def setup_camera_position(self):
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self.set_camera_orientation(
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phi=self.start_phi,
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theta=self.start_theta,
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)
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self.begin_ambient_camera_rotation(0.01)
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def add_prism(self):
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prism = self.prism = self.get_prism()
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prism.add_updater(
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lambda p: p.become(self.get_prism(
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self.q_tracker.get_value()
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))
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)
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self.add(prism)
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def add_axes(self):
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axes = self.axes = updating_mobject_from_func(self.get_axes)
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self.add(axes)
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def apply_quaternions(self):
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for quat in self.quaternions:
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self.change_q(quat)
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self.wait(2)
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#
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def get_unrotated_prism(self):
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return RandyPrism().scale(2)
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def get_prism(self, quaternion=[1, 0, 0, 0]):
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prism = self.get_unrotated_prism()
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angle, axis = angle_axis_from_quaternion(quaternion)
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prism.rotate(angle=angle, axis=axis, about_point=ORIGIN)
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return prism
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def get_axes(self):
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prism = self.prism
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centers = [sm.get_center() for sm in prism[:6]]
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axes = VGroup()
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for i in range(3):
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for u in [-1, 1]:
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vect = np.zeros(3)
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vect[i] = u
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dots = [np.dot(normalize(c), vect) for c in centers]
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max_i = np.argmax(dots)
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ec = centers[max_i]
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prism.get_edge_center(vect)
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p1 = np.zeros(3)
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p1[i] = ec[i]
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p1 *= dots[max_i]
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p2 = 10 * vect
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axes.add(Line(p1, p2))
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axes.set_stroke(LIGHT_GREY, 1)
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axes.set_shade_in_3d(True)
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return axes
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def change_q(self, value, run_time=3, added_anims=None, **kwargs):
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if added_anims is None:
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added_anims = []
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self.play(
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self.q_tracker.set_value, value,
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*added_anims,
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run_time=run_time,
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**kwargs
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)
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class PauseAndPlayOverlay(Scene):
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def construct(self):
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pause = TexMobject("=").rotate(TAU / 4)
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pause.stretch(2, 0)
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pause.scale(1.5)
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arrow = Vector(RIGHT, color=WHITE)
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interact = TextMobject("Interact...")
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group = VGroup(pause, arrow, interact)
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group.arrange_submobjects(RIGHT)
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group.scale(2)
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not_yet = TextMobject("...well, not yet")
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not_yet.scale(2)
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not_yet.next_to(group, DOWN, MED_LARGE_BUFF)
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self.play(Write(pause))
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self.play(
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GrowFromPoint(
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interact, arrow.get_left(),
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rate_func=squish_rate_func(smooth, 0.3, 1)
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),
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VFadeIn(interact),
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GrowArrow(arrow),
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)
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self.wait(2)
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self.play(Write(not_yet))
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self.wait()
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class RotationMatrix(ShowSeveralQuaternionRotations):
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CONFIG = {
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"start_phi": 60 * DEGREES,
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"start_theta": -60 * DEGREES,
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}
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def construct(self):
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self.add_q_tracker()
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self.setup_camera_position()
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self.add_prism()
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self.add_basis_vector_labels()
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self.add_axes()
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title = TextMobject("Rotation matrix")
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title.scale(1.5)
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title.to_corner(UL)
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self.add_fixed_in_frame_mobjects(title)
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angle = 75 * DEGREES
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axis = [0.3, 1, 0.3]
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matrix = rotation_matrix(angle=angle, axis=axis)
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matrix_mob = DecimalMatrix(matrix, h_buff=1.6)
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matrix_mob.next_to(title, DOWN)
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matrix_mob.to_edge(LEFT)
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title.next_to(matrix_mob, UP)
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self.add_fixed_in_frame_mobjects(matrix_mob)
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colors = [I_COLOR, J_COLOR, K_COLOR]
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matrix_mob.set_column_colors(*colors)
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columns = matrix_mob.get_columns()
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column_rects = VGroup(*[
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SurroundingRectangle(c).match_color(c[0])
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for c in columns
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])
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labels = VGroup(*[
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TextMobject(
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"Where", tex, "goes",
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tex_to_color_map={tex: rect.get_color()}
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).next_to(rect, DOWN)
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for letter, rect in zip(["\\i", "\\j", "k"], column_rects)
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for tex in ["$\\hat{\\textbf{%s}}$" % (letter)]
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])
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labels.space_out_submobjects(0.8)
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quaternion = quaternion_from_angle_axis(angle, axis)
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self.play(Write(matrix_mob))
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self.change_q(quaternion)
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self.wait()
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last_label = VectorizedPoint(matrix_mob.get_bottom())
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last_rect = VMobject()
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for label, rect in zip(labels, column_rects):
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self.add_fixed_in_frame_mobjects(rect, label)
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self.play(
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FadeIn(label),
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FadeOut(last_label),
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ShowCreation(rect),
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FadeOut(last_rect)
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)
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self.wait()
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last_label = label
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last_rect = rect
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self.play(FadeOut(last_label), FadeOut(last_rect))
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self.wait(5)
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def get_unrotated_prism(self):
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prism = RandyPrism()
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prism.scale(1.5)
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arrows = VGroup()
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for i, color in enumerate([I_COLOR, J_COLOR, K_COLOR]):
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vect = np.zeros(3)
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vect[i] = 1
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arrow = Arrow(
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prism.get_edge_center(vect), 2 * vect,
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preserve_tip_size_when_scaling=False,
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color=color,
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buff=0,
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)
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arrows.add(arrow)
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arrows.set_shade_in_3d(True)
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prism.arrows = arrows
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prism.add(arrows)
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return prism
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def add_basis_vector_labels(self):
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labels = VGroup(
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TexMobject("\\hat{\\textbf{\\i}}"),
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TexMobject("\\hat{\\textbf{\\j}}"),
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TexMobject("\\hat{\\textbf{k}}"),
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)
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def generate_updater(arrow):
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return lambda m: m.move_to(
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arrow.get_end() + 0.2 * normalize(arrow.get_vector()),
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)
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for arrow, label in zip(self.prism.arrows, labels):
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label.match_color(arrow)
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label.add_updater(generate_updater(arrow))
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self.add_fixed_orientation_mobjects(label)
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class EulerAnglesAndGimbal(SpecialThreeDScene):
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CONFIG = {
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"cut_axes_at_radius": True,
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"inner_r": 1.2,
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"outer_r": 2.6,
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"use_lightweight_axes": True,
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"lightweight_axes_num_pieces": 10,
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}
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def construct(self):
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self.setup_position()
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self.setup_cube()
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self.setup_gimbal()
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self.add_title()
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self.show_rotations()
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def add_axes(self):
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if self.use_lightweight_axes:
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self.axes = VGroup(*[
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VGroup(*Line(-v, v).scale(10).get_pieces(
|
||||
self.lightweight_axes_num_pieces
|
||||
))
|
||||
for v in [RIGHT, UP, OUT]
|
||||
])
|
||||
self.axes.set_stroke(WHITE, 1, opacity=0.5)
|
||||
self.axes.set_shade_in_3d(True)
|
||||
else:
|
||||
self.axes = self.get_axes()
|
||||
self.add(self.axes)
|
||||
|
||||
def setup_position(self):
|
||||
self.add_axes()
|
||||
self.set_camera_orientation(
|
||||
theta=-140 * DEGREES,
|
||||
phi=70 * DEGREES,
|
||||
)
|
||||
self.begin_ambient_camera_rotation(rate=0.015)
|
||||
|
||||
def setup_cube(self):
|
||||
cube = self.cube = RandyPrism()
|
||||
|
||||
points = [
|
||||
cube[5].get_corner([i, 0, j])
|
||||
for i in (-1, 1)
|
||||
for j in (-1, 1)
|
||||
]
|
||||
lines = VGroup()
|
||||
for point in points:
|
||||
point[1] = 0
|
||||
proj_point = normalize(point) * self.inner_r
|
||||
line = Line(point, proj_point)
|
||||
line.set_stroke(WHITE, 1)
|
||||
lines.add(line)
|
||||
lines.set_shade_in_3d(True)
|
||||
cube.add(lines)
|
||||
|
||||
self.add(cube)
|
||||
|
||||
def setup_gimbal(self):
|
||||
r1, r2, r3, r4, r5, r6, r7 = np.linspace(
|
||||
self.inner_r, self.outer_r, 7
|
||||
)
|
||||
gimbal = VGroup(
|
||||
self.get_ring(r5, r6),
|
||||
self.get_ring(r3, r4),
|
||||
self.get_ring(r1, r2),
|
||||
)
|
||||
for i, p1, p2 in [(0, r6, r7), (1, r4, r5), (2, r2, r3)]:
|
||||
annulus = gimbal[i]
|
||||
lines = VGroup(
|
||||
Line(p1 * UP, p2 * UP),
|
||||
Line(p1 * DOWN, p2 * DOWN),
|
||||
)
|
||||
lines.set_stroke(RED)
|
||||
annulus.lines = lines
|
||||
annulus.add(lines)
|
||||
gimbal[1].lines.rotate(90 * DEGREES, about_point=ORIGIN)
|
||||
gimbal.rotate(90 * DEGREES, RIGHT, about_point=ORIGIN)
|
||||
gimbal.set_shade_in_3d(True)
|
||||
self.gimbal = gimbal
|
||||
|
||||
def add_title(self):
|
||||
title = TextMobject("Euler angles")
|
||||
title.scale(1.5)
|
||||
title.to_corner(UL)
|
||||
angle_labels = VGroup(
|
||||
TexMobject("\\alpha").set_color(YELLOW),
|
||||
TexMobject("\\beta").set_color(GREEN),
|
||||
TexMobject("\\gamma").set_color(PINK),
|
||||
)
|
||||
angle_labels.scale(2)
|
||||
angle_labels.arrange_submobjects(RIGHT, buff=MED_LARGE_BUFF)
|
||||
angle_labels.next_to(title, DOWN, aligned_edge=LEFT)
|
||||
self.angle_labels = angle_labels
|
||||
|
||||
gl_label = VGroup(
|
||||
Arrow(LEFT, RIGHT, color=WHITE),
|
||||
TextMobject("Gimbal lock").scale(1.5),
|
||||
)
|
||||
gl_label.arrange_submobjects(RIGHT)
|
||||
gl_label.next_to(title, RIGHT)
|
||||
self.gimbal_lock_label = gl_label
|
||||
|
||||
VGroup(title, angle_labels, gl_label).center().to_edge(UP)
|
||||
|
||||
self.add_fixed_in_frame_mobjects(title, angle_labels, gl_label)
|
||||
self.remove(angle_labels)
|
||||
self.remove(gl_label)
|
||||
|
||||
def show_rotations(self):
|
||||
cube = self.cube
|
||||
gimbal = self.gimbal
|
||||
self.add(cube, gimbal)
|
||||
|
||||
kwargs = {
|
||||
"about_point": ORIGIN,
|
||||
"run_time": 3,
|
||||
}
|
||||
angles = [-60 * DEGREES, 50 * DEGREES, 45 * DEGREES]
|
||||
for i, angle in zip(it.count(), angles):
|
||||
vect = gimbal[i].lines[0].get_vector()
|
||||
line = self.get_dotted_line(vect)
|
||||
angle_label = self.angle_labels[i]
|
||||
line.match_color(angle_label)
|
||||
self.play(
|
||||
ShowCreation(line),
|
||||
FadeInFromDown(angle_label)
|
||||
)
|
||||
self.play(
|
||||
Rotate(
|
||||
VGroup(cube, gimbal[i:]),
|
||||
angle=angle,
|
||||
axis=vect,
|
||||
**kwargs
|
||||
),
|
||||
)
|
||||
self.play(FadeOut(line))
|
||||
self.wait()
|
||||
self.wait(3)
|
||||
self.play(Write(self.gimbal_lock_label))
|
||||
self.play(
|
||||
Rotate(
|
||||
VGroup(cube, gimbal[1:]),
|
||||
angle=-angles[1],
|
||||
axis=gimbal[1].lines[0].get_vector(),
|
||||
**kwargs
|
||||
)
|
||||
)
|
||||
self.wait()
|
||||
self.play(
|
||||
Rotate(
|
||||
VGroup(cube, gimbal[0:]),
|
||||
angle=-angles[0],
|
||||
axis=gimbal[0].lines[0].get_vector(),
|
||||
**kwargs
|
||||
)
|
||||
)
|
||||
self.wait()
|
||||
for angle in [-120 * DEGREES, 120 * DEGREES]:
|
||||
self.play(
|
||||
Rotate(
|
||||
VGroup(cube, gimbal[2:]),
|
||||
angle=angle,
|
||||
axis=gimbal[2].lines[0].get_vector(),
|
||||
run_time=4,
|
||||
about_point=ORIGIN
|
||||
)
|
||||
)
|
||||
self.wait(4)
|
||||
|
||||
#
|
||||
def get_dotted_line(self, vect):
|
||||
line = DashedLine(ORIGIN, 10 * normalize(vect))
|
||||
line.set_shade_in_3d(True)
|
||||
line.set_stroke(YELLOW, 5)
|
||||
line.center()
|
||||
return line
|
||||
|
||||
def get_ring(self, in_r, out_r, angle=TAU / 4):
|
||||
result = VGroup()
|
||||
for start_angle in np.arange(0, TAU, angle):
|
||||
start_angle += angle / 2
|
||||
sector = AnnularSector(
|
||||
inner_radius=in_r,
|
||||
outer_radius=out_r,
|
||||
angle=angle,
|
||||
start_angle=start_angle
|
||||
)
|
||||
sector.set_fill(LIGHT_GREY, 0.8)
|
||||
arcs = VGroup(*[
|
||||
Arc(
|
||||
angle=angle,
|
||||
start_angle=start_angle,
|
||||
radius=r
|
||||
)
|
||||
for r in [in_r, out_r]
|
||||
])
|
||||
arcs.set_stroke(BLACK, 1, opacity=0.5)
|
||||
sector.add(arcs)
|
||||
result.add(sector)
|
||||
return result
|
||||
|
||||
|
||||
class QuaternionsDescribingRotation(EulerAnglesAndGimbal):
|
||||
CONFIG = {
|
||||
"use_lightweight_axes": True,
|
||||
"quaternions_and_imaginary_part_labels": [
|
||||
([1, 1, 0, 0], "{i}"),
|
||||
# ([1, 0, 1, 0], "{j}"),
|
||||
# ([0, 0, 0, 1], "{k}"),
|
||||
# ([1, 1, 1, 1], "\\left({{i} + {j} + {k} \\over \\sqrt{3}}\\right)"),
|
||||
],
|
||||
}
|
||||
|
||||
def construct(self):
|
||||
self.setup_position()
|
||||
self.show_rotations()
|
||||
|
||||
def show_rotations(self):
|
||||
for quat, ipl in self.quaternions_and_imaginary_part_labels:
|
||||
quat = normalize(quat)
|
||||
axis = quat[1:]
|
||||
angle = 2 * np.arccos(quat[0])
|
||||
label = self.get_label(angle, ipl)
|
||||
|
||||
prism = RandyPrism()
|
||||
prism.scale(2)
|
||||
|
||||
self.play(
|
||||
LaggedStart(FadeInFromDown, label),
|
||||
FadeIn(prism),
|
||||
)
|
||||
self.play(Rotate(
|
||||
prism,
|
||||
angle=angle, axis=axis,
|
||||
run_time=3,
|
||||
about_point=ORIGIN,
|
||||
))
|
||||
|
||||
|
||||
#
|
||||
def get_label(self, angle, imaginary_part_label):
|
||||
deg = int(angle / DEGREES)
|
||||
ipl = imaginary_part_label
|
||||
kwargs = {
|
||||
"tex_to_color_map": {
|
||||
"{i}": I_COLOR,
|
||||
"{j}": J_COLOR,
|
||||
"{k}": K_COLOR,
|
||||
}
|
||||
}
|
||||
p_label = TexMobject(
|
||||
"x{i} + y{j} + z{k}", **kwargs
|
||||
)
|
||||
arrow = TexMobject(
|
||||
"\\rightarrow"
|
||||
)
|
||||
q_label = TexMobject(
|
||||
"\\big(\\cos(%d^\\circ) + \\sin(%d^\\circ)%s \\big)" % (deg, deg, ipl),
|
||||
**kwargs
|
||||
)
|
||||
inner_p_label = TexMobject(
|
||||
"\\left(x{i} + y{j} + z{k} \\right)",
|
||||
**kwargs
|
||||
)
|
||||
q_inv_label = TexMobject(
|
||||
"\\big(\\cos(-%d^\\circ) + \\sin(-%d^\\circ)%s \\big)" % (deg, deg, ipl),
|
||||
**kwargs
|
||||
)
|
||||
equation = VGroup(
|
||||
p_label, arrow, q_label, inner_p_label, q_inv_label
|
||||
)
|
||||
equation.arrange_submobjects(RIGHT, buff=SMALL_BUFF)
|
||||
equation.set_width(FRAME_WIDTH - 1)
|
||||
equation.to_edge(UP)
|
||||
|
||||
parts_text_colors = [
|
||||
(p_label, "\\text{3d point}", YELLOW),
|
||||
(q_label, "q", PINK),
|
||||
(inner_p_label, "\\text{3d point}", YELLOW),
|
||||
(q_inv_label, "q^{-1}", PINK),
|
||||
]
|
||||
braces = VGroup()
|
||||
for part, text, color in parts_text_colors:
|
||||
brace = Brace(part, DOWN, buff=SMALL_BUFF)
|
||||
label = brace.get_tex(text, buff=MED_SMALL_BUFF)
|
||||
label.set_color(color)
|
||||
brace.add(label)
|
||||
braces.add(brace)
|
||||
braces[-1][-1].shift(0.2 * UR)
|
||||
|
||||
equation.add_to_back(BackgroundRectangle(equation))
|
||||
equation.braces = braces
|
||||
equation.add(*braces)
|
||||
|
||||
self.add_fixed_in_frame_mobjects(equation)
|
||||
self.add_fixed_in_frame_mobjects(braces)
|
||||
return equation
|
||||
|
|
|
|||
Loading…
Add table
Reference in a new issue