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Jquery Easing function

I was studying a jquery easing function to use in a java application and ended with this:

// t: current time, b: begInnIng value, c: change 开发者_JS百科In value, d: duration
    float easeInOutQuad (float x, float t, float b, float c, float d) {
        if ((t/=d/2) < 1) return c/2*t*t + b;
        return -c/2 * ((--t)*(t-2) - 1) + b;
    }

can someone teach me how do i plug this into my animated sphere movement?

EDIT: I wont put here unnecessary code describing my sphere movement. Imagine a sphere, with X position named X and it will go from 0 to 1000, using this easing function. How do i feed the function?


This is basically psuedo-java code, but I tested it and it works. I drew a small circle instead of using a sphere:

Sphere sphere = new Sphere();

// you might want these to be in the sphere class
float begin;
float change;
float time;
long start;
float duration;
float destX = 200;

// setup, do this when you want to start the animation
void init(){
  begin = sphere.x;
  change = destX - begin;
  time = 0;
  start = System.currentTimeMillis();
  duration = 1000;
}

// loop code, may also be where you render the sphere
void loop(){
  if (time <= duration){
    sphere.x = easeInOutQuad(time, begin, change, duration);
  }else{
    // animation is over, stop the loop
  }
  time = System.currentTimeMillis() - start;
  sphere.render();
}

float easeInOutQuad (float t, float b, float c, float d) {
  if ((t/=d/2) < 1) return c/2*t*t + b;
  return -c/2 * ((--t)*(t-2) - 1) + b;
}

class Sphere{
  float x = 0;
  void render(){
    ellipse(x, 100, 10, 10);
  } 
}

You'll probably want to move things around depending on your set up, but this is how you can use this style of easing equation.

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