Further development on VectorField

This commit is contained in:
Grant Sanderson 2024-11-15 09:07:46 -08:00
parent 64ae1364ca
commit 0ad5a0e76e

View file

@ -3,6 +3,7 @@ from __future__ import annotations
import itertools as it
import numpy as np
from scipy.integrate import solve_ivp
from manimlib.constants import FRAME_HEIGHT, FRAME_WIDTH
from manimlib.constants import BLUE, WHITE
@ -26,7 +27,7 @@ from typing import TYPE_CHECKING
if TYPE_CHECKING:
from typing import Callable, Iterable, Sequence, TypeVar, Tuple
from manimlib.typing import ManimColor, Vect3, VectN, Vect3Array, Vect4Array
from manimlib.typing import ManimColor, Vect3, VectN, Vect2Array, Vect3Array, Vect4Array
from manimlib.mobject.coordinate_systems import CoordinateSystem
from manimlib.mobject.mobject import Mobject
@ -68,6 +69,16 @@ def get_rgb_gradient_function(
####
def ode_solution_points(function, state0, time, dt=0.01):
solution = solve_ivp(
lambda t, state: function(state),
t_span=(0, time),
y0=state0,
t_eval=np.arange(0, time, dt)
)
return solution.y.T
def move_along_vector_field(
mobject: Mobject,
func: Callable[[Vect3], Vect3]
@ -128,12 +139,12 @@ def get_sample_coords(
class VectorField(VMobject):
def __init__(
self,
func: Callable[Sequence[float], Sequence[float]],
func: Callable[[VectArray], VectArray],
coordinate_system: CoordinateSystem,
step_multiple: float = 0.5,
magnitude_range: Optional[Tuple[float, float]] = None,
color_map_name: Optional[str] = "3b1b_colormap",
color_map: Optional[Callable[Sequence[float]], Vect4Array] = None,
color_map: Optional[Callable[[Sequence[float]], Vect4Array]] = None,
stroke_color: ManimColor = BLUE,
stroke_opacity: float = 1.0,
stroke_width: float = 2,
@ -281,9 +292,9 @@ class VectorField(VMobject):
if self.color_map is not None:
self.get_stroke_colors() # Ensures the array is updated to appropriate length
low, high = self.magnitude_range
self.data['stroke_rgba'][:] = self.color_map(
self.data['stroke_rgba'][:, :3] = self.color_map(
inverse_interpolate(low, high, np.repeat(output_norms, 8)[:-1])
)
)[:, :3]
if self.norm_to_opacity_func is not None:
self.get_stroke_opacities()[:] = self.norm_to_opacity_func(
@ -310,6 +321,165 @@ class TimeVaryingVectorField(VectorField):
self.time += dt
class StreamLines(VGroup):
def __init__(
self,
func: Callable[[VectArray], VectArray],
coordinate_system: CoordinateSystem,
step_multiple: float = 0.5,
n_repeats: int = 1,
noise_factor: float | None = None,
# Config for drawing lines
solution_time: float = 3,
dt: float = 0.05,
arc_len: float = 3,
max_time_steps: int = 200,
n_samples_per_line: int = 10,
cutoff_norm: float = 15,
# Style info
stroke_width: float = 1.0,
stroke_color: ManimColor = WHITE,
stroke_opacity: float = 1,
color_by_magnitude: bool = True,
magnitude_range: Tuple[float, float] = (0, 2.0),
taper_stroke_width: bool = False,
color_map: str = "3b1b_colormap",
**kwargs
):
super().__init__(**kwargs)
self.func = func
self.coordinate_system = coordinate_system
self.step_multiple = step_multiple
self.n_repeats = n_repeats
self.noise_factor = noise_factor
self.solution_time = solution_time
self.dt = dt
self.arc_len = arc_len
self.max_time_steps = max_time_steps
self.n_samples_per_line = n_samples_per_line
self.cutoff_norm = cutoff_norm
self.stroke_width = stroke_width
self.stroke_color = stroke_color
self.stroke_opacity = stroke_opacity
self.color_by_magnitude = color_by_magnitude
self.magnitude_range = magnitude_range
self.taper_stroke_width = taper_stroke_width
self.color_map = color_map
self.draw_lines()
self.init_style()
def point_func(self, points: Vect3Array) -> Vect3:
in_coords = np.array(self.coordinate_system.p2c(points)).T
out_coords = self.func(in_coords)
origin = self.coordinate_system.get_origin()
return self.coordinate_system.c2p(*out_coords.T) - origin
def draw_lines(self) -> None:
lines = []
origin = self.coordinate_system.get_origin()
# Todo, it feels like coordinate system should just have
# the ODE solver built into it, no?
lines = []
for coords in self.get_sample_coords():
solution_coords = ode_solution_points(self.func, coords, self.solution_time, self.dt)
line = VMobject()
line.set_points_smoothly(self.coordinate_system.c2p(*solution_coords.T))
# TODO, account for arc length somehow?
line.virtual_time = self.solution_time
lines.append(line)
self.set_submobjects(lines)
def get_sample_coords(self):
cs = self.coordinate_system
sample_coords = get_sample_coords(cs, self.step_multiple)
noise_factor = self.noise_factor
if noise_factor is None:
noise_factor = cs.get_x_unit_size() * self.step_multiple * 0.5
return np.array([
coords + noise_factor * np.random.random(coords.shape)
for n in range(self.n_repeats)
for coords in sample_coords
])
def get_start_points(self) -> Vect3Array:
cs = self.coordinate_system
sample_coords = get_sample_coords(cs, self.step_multiple)
noise_factor = self.noise_factor
if noise_factor is None:
noise_factor = cs.get_x_unit_size() * self.step_multiple * 0.5
return np.array([
cs.c2p(*coords) + noise_factor * np.random.random(3)
for n in range(self.n_repeats)
for coords in sample_coords
])
def init_style(self) -> None:
if self.color_by_magnitude:
values_to_rgbs = get_vectorized_rgb_gradient_function(
*self.magnitude_range, self.color_map,
)
cs = self.coordinate_system
for line in self.submobjects:
norms = [
get_norm(self.func(*cs.p2c(point)))
for point in line.get_points()
]
rgbs = values_to_rgbs(norms)
rgbas = np.zeros((len(rgbs), 4))
rgbas[:, :3] = rgbs
rgbas[:, 3] = self.stroke_opacity
line.set_rgba_array(rgbas, "stroke_rgba")
else:
self.set_stroke(self.stroke_color, opacity=self.stroke_opacity)
if self.taper_stroke_width:
width = [0, self.stroke_width, 0]
else:
width = self.stroke_width
self.set_stroke(width=width)
class AnimatedStreamLines(VGroup):
def __init__(
self,
stream_lines: StreamLines,
lag_range: float = 4,
rate_multiple: float = 1.0,
line_anim_config: dict = dict(
rate_func=linear,
time_width=1.0,
),
**kwargs
):
super().__init__(**kwargs)
self.stream_lines = stream_lines
for line in stream_lines:
line.anim = VShowPassingFlash(
line,
run_time=line.virtual_time / rate_multiple,
**line_anim_config,
)
line.anim.begin()
line.time = -lag_range * np.random.random()
self.add(line.anim.mobject)
self.add_updater(lambda m, dt: m.update(dt))
def update(self, dt: float) -> None:
stream_lines = self.stream_lines
for line in stream_lines:
line.time += dt
adjusted_time = max(line.time, 0) % line.anim.run_time
line.anim.update(adjusted_time / line.anim.run_time)
class OldVectorField(VGroup):
def __init__(
self,
@ -371,155 +541,3 @@ class OldVectorField(VGroup):
opacity=self.opacity,
)
return vect
class StreamLines(VGroup):
def __init__(
self,
func: Callable[[float, float], Sequence[float]],
coordinate_system: CoordinateSystem,
step_multiple: float = 0.5,
n_repeats: int = 1,
noise_factor: float | None = None,
# Config for drawing lines
dt: float = 0.05,
arc_len: float = 3,
max_time_steps: int = 200,
n_samples_per_line: int = 10,
cutoff_norm: float = 15,
# Style info
stroke_width: float = 1.0,
stroke_color: ManimColor = WHITE,
stroke_opacity: float = 1,
color_by_magnitude: bool = True,
magnitude_range: Tuple[float, float] = (0, 2.0),
taper_stroke_width: bool = False,
color_map: str = "3b1b_colormap",
**kwargs
):
super().__init__(**kwargs)
self.func = func
self.coordinate_system = coordinate_system
self.step_multiple = step_multiple
self.n_repeats = n_repeats
self.noise_factor = noise_factor
self.dt = dt
self.arc_len = arc_len
self.max_time_steps = max_time_steps
self.n_samples_per_line = n_samples_per_line
self.cutoff_norm = cutoff_norm
self.stroke_width = stroke_width
self.stroke_color = stroke_color
self.stroke_opacity = stroke_opacity
self.color_by_magnitude = color_by_magnitude
self.magnitude_range = magnitude_range
self.taper_stroke_width = taper_stroke_width
self.color_map = color_map
self.draw_lines()
self.init_style()
def point_func(self, point: Vect3) -> Vect3:
in_coords = self.coordinate_system.p2c(point)
out_coords = self.func(*in_coords)
return self.coordinate_system.c2p(*out_coords)
def draw_lines(self) -> None:
lines = []
origin = self.coordinate_system.get_origin()
for point in self.get_start_points():
points = [point]
total_arc_len = 0
time = 0
for x in range(self.max_time_steps):
time += self.dt
last_point = points[-1]
new_point = last_point + self.dt * (self.point_func(last_point) - origin)
points.append(new_point)
total_arc_len += get_norm(new_point - last_point)
if get_norm(last_point) > self.cutoff_norm:
break
if total_arc_len > self.arc_len:
break
line = VMobject()
line.virtual_time = time
step = max(1, int(len(points) / self.n_samples_per_line))
line.set_points_as_corners(points[::step])
line.make_smooth(approx=True)
lines.append(line)
self.set_submobjects(lines)
def get_start_points(self) -> Vect3Array:
cs = self.coordinate_system
sample_coords = get_sample_coords(
cs, self.step_multiple,
)
noise_factor = self.noise_factor
if noise_factor is None:
noise_factor = cs.x_range[2] * self.step_multiple * 0.5
return np.array([
cs.c2p(*coords) + noise_factor * np.random.random(3)
for n in range(self.n_repeats)
for coords in sample_coords
])
def init_style(self) -> None:
if self.color_by_magnitude:
values_to_rgbs = get_vectorized_rgb_gradient_function(
*self.magnitude_range, self.color_map,
)
cs = self.coordinate_system
for line in self.submobjects:
norms = [
get_norm(self.func(*cs.p2c(point)))
for point in line.get_points()
]
rgbs = values_to_rgbs(norms)
rgbas = np.zeros((len(rgbs), 4))
rgbas[:, :3] = rgbs
rgbas[:, 3] = self.stroke_opacity
line.set_rgba_array(rgbas, "stroke_rgba")
else:
self.set_stroke(self.stroke_color, opacity=self.stroke_opacity)
if self.taper_stroke_width:
width = [0, self.stroke_width, 0]
else:
width = self.stroke_width
self.set_stroke(width=width)
class AnimatedStreamLines(VGroup):
def __init__(
self,
stream_lines: StreamLines,
lag_range: float = 4,
line_anim_config: dict = dict(
rate_func=linear,
time_width=1.0,
),
**kwargs
):
super().__init__(**kwargs)
self.stream_lines = stream_lines
for line in stream_lines:
line.anim = VShowPassingFlash(
line,
run_time=line.virtual_time,
**line_anim_config,
)
line.anim.begin()
line.time = -lag_range * np.random.random()
self.add(line.anim.mobject)
self.add_updater(lambda m, dt: m.update(dt))
def update(self, dt: float) -> None:
stream_lines = self.stream_lines
for line in stream_lines:
line.time += dt
adjusted_time = max(line.time, 0) % line.anim.run_time
line.anim.update(adjusted_time / line.anim.run_time)