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ease.js
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// easing functions from "Tween.js"
exports.linear = function(n){
return n;
};
exports.inQuad = function(n){
return n * n;
};
exports.outQuad = function(n){
return n * (2 - n);
};
exports.inOutQuad = function(n){
n *= 2;
if (n < 1) return 0.5 * n * n;
return - 0.5 * (--n * (n - 2) - 1);
};
exports.inCube = function(n){
return n * n * n;
};
exports.outCube = function(n){
return --n * n * n + 1;
};
exports.inOutCube = function(n){
n *= 2;
if (n < 1) return 0.5 * n * n * n;
return 0.5 * ((n -= 2 ) * n * n + 2);
};
exports.inQuart = function(n){
return n * n * n * n;
};
exports.outQuart = function(n){
return 1 - (--n * n * n * n);
};
exports.inOutQuart = function(n){
n *= 2;
if (n < 1) return 0.5 * n * n * n * n;
return -0.5 * ((n -= 2) * n * n * n - 2);
};
exports.inQuint = function(n){
return n * n * n * n * n;
}
exports.outQuint = function(n){
return --n * n * n * n * n + 1;
}
exports.inOutQuint = function(n){
n *= 2;
if (n < 1) return 0.5 * n * n * n * n * n;
return 0.5 * ((n -= 2) * n * n * n * n + 2);
};
exports.inSine = function(n){
return 1 - Math.cos(n * Math.PI / 2 );
};
exports.outSine = function(n){
return Math.sin(n * Math.PI / 2);
};
exports.inOutSine = function(n){
return .5 * (1 - Math.cos(Math.PI * n));
};
exports.inExpo = function(n){
return 0 == n ? 0 : Math.pow(1024, n - 1);
};
exports.outExpo = function(n){
return 1 == n ? n : 1 - Math.pow(2, -10 * n);
};
exports.inOutExpo = function(n){
if (0 == n) return 0;
if (1 == n) return 1;
if ((n *= 2) < 1) return .5 * Math.pow(1024, n - 1);
return .5 * (-Math.pow(2, -10 * (n - 1)) + 2);
};
exports.inCirc = function(n){
return 1 - Math.sqrt(1 - n * n);
};
exports.outCirc = function(n){
return Math.sqrt(1 - (--n * n));
};
exports.inOutCirc = function(n){
n *= 2
if (n < 1) return -0.5 * (Math.sqrt(1 - n * n) - 1);
return 0.5 * (Math.sqrt(1 - (n -= 2) * n) + 1);
};
exports.inBack = function(n){
var s = 1.70158;
return n * n * (( s + 1 ) * n - s);
};
exports.outBack = function(n){
var s = 1.70158;
return --n * n * ((s + 1) * n + s) + 1;
};
exports.inOutBack = function(n){
var s = 1.70158 * 1.525;
if ( ( n *= 2 ) < 1 ) return 0.5 * ( n * n * ( ( s + 1 ) * n - s ) );
return 0.5 * ( ( n -= 2 ) * n * ( ( s + 1 ) * n + s ) + 2 );
};
exports.inBounce = function(n){
return 1 - exports.outBounce(1 - n);
};
exports.outBounce = function(n){
if ( n < ( 1 / 2.75 ) ) {
return 7.5625 * n * n;
} else if ( n < ( 2 / 2.75 ) ) {
return 7.5625 * ( n -= ( 1.5 / 2.75 ) ) * n + 0.75;
} else if ( n < ( 2.5 / 2.75 ) ) {
return 7.5625 * ( n -= ( 2.25 / 2.75 ) ) * n + 0.9375;
} else {
return 7.5625 * ( n -= ( 2.625 / 2.75 ) ) * n + 0.984375;
}
};
exports.inOutBounce = function(n){
if (n < .5) return exports.inBounce(n * 2) * .5;
return exports.outBounce(n * 2 - 1) * .5 + .5;
};
exports.inElastic = function(n){
var s, a = 0.1, p = 0.4;
if ( n === 0 ) return 0;
if ( n === 1 ) return 1;
if ( !a || a < 1 ) { a = 1; s = p / 4; }
else s = p * Math.asin( 1 / a ) / ( 2 * Math.PI );
return - ( a * Math.pow( 2, 10 * ( n -= 1 ) ) * Math.sin( ( n - s ) * ( 2 * Math.PI ) / p ) );
};
exports.outElastic = function(n){
var s, a = 0.1, p = 0.4;
if ( n === 0 ) return 0;
if ( n === 1 ) return 1;
if ( !a || a < 1 ) { a = 1; s = p / 4; }
else s = p * Math.asin( 1 / a ) / ( 2 * Math.PI );
return ( a * Math.pow( 2, - 10 * n) * Math.sin( ( n - s ) * ( 2 * Math.PI ) / p ) + 1 );
};
exports.inOutElastic = function(n){
var s, a = 0.1, p = 0.4;
if ( n === 0 ) return 0;
if ( n === 1 ) return 1;
if ( !a || a < 1 ) { a = 1; s = p / 4; }
else s = p * Math.asin( 1 / a ) / ( 2 * Math.PI );
if ( ( n *= 2 ) < 1 ) return - 0.5 * ( a * Math.pow( 2, 10 * ( n -= 1 ) ) * Math.sin( ( n - s ) * ( 2 * Math.PI ) / p ) );
return a * Math.pow( 2, -10 * ( n -= 1 ) ) * Math.sin( ( n - s ) * ( 2 * Math.PI ) / p ) * 0.5 + 1;
};
// aliases
exports['in-quad'] = exports.inQuad;
exports['out-quad'] = exports.outQuad;
exports['in-out-quad'] = exports.inOutQuad;
exports['in-cube'] = exports.inCube;
exports['out-cube'] = exports.outCube;
exports['in-out-cube'] = exports.inOutCube;
exports['in-quart'] = exports.inQuart;
exports['out-quart'] = exports.outQuart;
exports['in-out-quart'] = exports.inOutQuart;
exports['in-quint'] = exports.inQuint;
exports['out-quint'] = exports.outQuint;
exports['in-out-quint'] = exports.inOutQuint;
exports['in-sine'] = exports.inSine;
exports['out-sine'] = exports.outSine;
exports['in-out-sine'] = exports.inOutSine;
exports['in-expo'] = exports.inExpo;
exports['out-expo'] = exports.outExpo;
exports['in-out-expo'] = exports.inOutExpo;
exports['in-circ'] = exports.inCirc;
exports['out-circ'] = exports.outCirc;
exports['in-out-circ'] = exports.inOutCirc;
exports['in-back'] = exports.inBack;
exports['out-back'] = exports.outBack;
exports['in-out-back'] = exports.inOutBack;
exports['in-bounce'] = exports.inBounce;
exports['out-bounce'] = exports.outBounce;
exports['in-out-bounce'] = exports.inOutBounce;
exports['in-elastic'] = exports.inElastic;
exports['out-elastic'] = exports.outElastic;
exports['in-out-elastic'] = exports.inOutElastic;