PowerToys/src/common/animation.h

#pragma once
#include <chrono>

/*
  Usage:
    When creating animation contstructor takes one parameter - how long
    should the animation take in seconds.

    Call reset() when starting animation.

    When redering, call value() to get value from 0 to 1 - depending on animation
    progress.
*/
class Animation {
public:
  enum AnimFunctions {
    LINEAR = 0,
    EASE_OUT_EXPO
  };

  Animation(double duration = 1, double start = 0, double stop = 1);
  void reset();
  void reset(double duration);
  void reset(double duration, double start, double stop);
  double value(AnimFunctions apply_function) const;
  bool done() const;
private:
  static double apply_animation_function(double t, AnimFunctions apply_function);
  std::chrono::high_resolution_clock::time_point start;
  double start_value, end_value, duration;
};