js动画函数
var tween = {
linear: function (t, b, c, d) {
return c * t / d + b;
},
easeIn: function (t, b, c, d) {
return c * ( t /= d ) * t + b;
}, strongEaseIn: function (t, b, c, d) {
return c * ( t /= d ) * t * t * t * t + b;
},
strongEaseOut: function (t, b, c, d) {
return c * ( ( t = t / d - 1) * t * t * t * t + 1 ) + b;
},
sineaseIn: function (t, b, c, d) {
return c * ( t /= d) * t * t + b;
},
sineaseOut: function (t, b, c, d) {
return c * ( ( t = t / d - 1) * t * t + 1 ) + b;
}
};