refactor 3-more into separate books

5-animation/2-css-transitions/1-animate-logo-css/source.view/animate.js

@@ -0,0 +1,92 @@
+/**
+ Docs: http://learn.javascript.ru/tutorial/lib
+*/
+
+function animate(opts) {
+
+  var start = new Date;
+  var delta = opts.delta || linear;
+
+  var timer = setInterval(function() {
+    var progress = (new Date - start) / opts.duration;
+
+    if (progress > 1) progress = 1;
+
+    opts.step( delta(progress) );
+
+    if (progress == 1) {
+      clearInterval(timer);
+      opts.complete && opts.complete();
+    }
+  }, opts.delay || 13);
+
+  return timer;
+}
+
+/**
+ Анимация стиля opts.prop у элемента opts.elem
+ от opts.from до opts.to продолжительностью opts.duration
+ в конце opts.complete
+
+ Например: animateProp({ elem: ..., prop: 'height', start:0, end: 100, duration: 1000 })
+*/
+function animateProp(opts) {
+  var start = opts.start, end = opts.end, prop = opts.prop;
+
+  opts.step = function(delta) {
+    var value = Math.round(start + (end - start)*delta);
+    opts.elem.style[prop] = value + 'px';
+  }
+  return animate(opts);
+}
+
+// ------------------ Delta ------------------
+
+function elastic(progress) {
+  return Math.pow(2, 10 * (progress-1)) * Math.cos(20*Math.PI*1.5/3*progress);
+}
+
+function linear(progress) {
+  return progress;
+}
+
+function quad(progress) {
+  return Math.pow(progress, 2);
+}
+
+function quint(progress) {
+  return Math.pow(progress, 5);
+}
+
+function circ(progress) {
+  return 1 - Math.sin(Math.acos(progress));
+}
+
+function back(progress) {
+  return Math.pow(progress, 2) * ((1.5 + 1) * progress - 1.5);
+}
+
+
+function bounce(progress) {
+  for(var a = 0, b = 1, result; 1; a += b, b /= 2) {
+    if (progress >= (7 - 4 * a) / 11) {
+      return -Math.pow((11 - 6 * a - 11 * progress) / 4, 2) + Math.pow(b, 2);
+    }
+  }
+}
+
+function makeEaseInOut(delta) {
+  return function(progress) {
+    if (progress < .5)
+      return delta(2*progress) / 2;
+    else
+      return (2 - delta(2*(1-progress))) / 2;
+  }
+}
+
+
+function makeEaseOut(delta) {
+  return function(progress) {
+    return 1 - delta(1 - progress);
+  }
+}