Files
manim/mobject/value_tracker.py
Grant Sanderson 858051a806 After running 2to3
2018-08-09 17:56:05 -07:00

48 lines
1.2 KiB
Python

import numpy as np
from constants import *
from mobject.types.vectorized_mobject import VectorizedPoint
# TODO: Rather than using VectorizedPoint, there should be some UndisplayedPointSet type
class ValueTracker(VectorizedPoint):
"""
Note meant to be displayed. Instead the position encodes some
number, often one which another animation or continual_animation
uses for its update function, and by treating it as a mobject it can
still be animated and manipulated just like anything else.
"""
def __init__(self, value=0, **kwargs):
VectorizedPoint.__init__(self, **kwargs)
self.set_value(value)
def get_value(self):
return self.get_center()[0]
def set_value(self, value):
self.move_to(value * RIGHT)
return self
def increment_value(self, d_value):
self.set_value(self.get_value() + d_value)
class ExponentialValueTracker(ValueTracker):
"""
Operates just like ValueTracker, except it encodes the value as the
exponential of a position coordinate, which changes how interpolation
behaves
"""
def get_value(self):
return np.exp(self.get_center()[0])
def set_value(self, value):
self.move_to(np.log(value) * RIGHT)
return self