1 files changed, 49 insertions, 0 deletions
diff --git a/catapult/third_party/polymer/components/web-animations-js/src/interpolation.js b/catapult/third_party/polymer/components/web-animations-js/src/interpolation.js
new file mode 100644
index 00000000..ba63ed35
--- /dev/null
+++ b/catapult/third_party/polymer/components/web-animations-js/src/interpolation.js
@@ -0,0 +1,49 @@
+// Copyright 2014 Google Inc. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+//     You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+//     See the License for the specific language governing permissions and
+// limitations under the License.
+
+(function(scope, testing) {
+
+  function interpolate(from, to, f) {
+    if ((typeof from == 'number') && (typeof to == 'number')) {
+      return from * (1 - f) + to * f;
+    }
+    if ((typeof from == 'boolean') && (typeof to == 'boolean')) {
+      return f < 0.5 ? from : to;
+    }
+
+    WEB_ANIMATIONS_TESTING && console.assert(
+        Array.isArray(from) && Array.isArray(to),
+        'If interpolation arguments are not numbers or bools they must be arrays');
+
+    if (from.length == to.length) {
+      var r = [];
+      for (var i = 0; i < from.length; i++) {
+        r.push(interpolate(from[i], to[i], f));
+      }
+      return r;
+    }
+    throw 'Mismatched interpolation arguments ' + from + ':' + to;
+  }
+
+  scope.Interpolation = function(from, to, convertToString) {
+    return function(f) {
+      return convertToString(interpolate(from, to, f));
+    }
+  };
+
+  if (WEB_ANIMATIONS_TESTING) {
+    testing.interpolate = interpolate;
+  }
+
+})(webAnimations1, webAnimationsTesting);