Class EasingFunctions

Standard easing functions for motion in Excalibur, defined on a domain of [0, duration] and a range from [+startValue,+endValue] Given a time, the function will return a value from positive startValue to positive endValue.

function Linear (t) {
   return t * t;
}

// accelerating from zero velocity
function EaseInQuad (t) {
   return t * t;
}

// decelerating to zero velocity
function EaseOutQuad (t) {
   return t * (2 - t);
}

// acceleration until halfway, then deceleration
function EaseInOutQuad (t) {
   return t < .5 ? 2 * t * t : -1 + (4 - 2 * t) * t;
}

// accelerating from zero velocity
function EaseInCubic (t) {
   return t * t * t;
}

// decelerating to zero velocity
function EaseOutCubic (t) {
   return (--t) * t * t + 1;
}

// acceleration until halfway, then deceleration
function EaseInOutCubic (t) {
   return t < .5 ? 4 * t * t * t : (t - 1) * (2 * t - 2) * (2 * t - 2) + 1;
}