Define accelerated steps time function.

ui/gfx/animation/steps_unittest.cc

Index: ui/gfx/animation/steps_unittest.cc
diff --git a/ui/gfx/animation/steps_unittest.cc b/ui/gfx/animation/steps_unittest.cc
new file mode 100644
index 0000000000000000000000000000000000000000..cb317de7a37cfd207a7e0711e2fbc8f021d51e1f
--- /dev/null
+++ b/ui/gfx/animation/steps_unittest.cc
@@ -0,0 +1,84 @@
+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "ui/gfx/animation/steps.h"
+
+#include "base/memory/scoped_ptr.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace gfx {
+namespace {
+
+TEST(StepsTest, Basic) {
+  Steps function(36, false);
+
+  EXPECT_DOUBLE_EQ(function.Solve(-1.0), 0.0);
+  EXPECT_DOUBLE_EQ(function.Solve(0), 0.0);
+  EXPECT_DOUBLE_EQ(function.Solve(0.05), 1.0 / 36.0);
+  EXPECT_DOUBLE_EQ(function.Solve(0.1), 3.0 / 36.0);
+  EXPECT_DOUBLE_EQ(function.Solve(0.15), 5.0 / 36.0);
+  EXPECT_DOUBLE_EQ(function.Solve(0.2), 7.0 / 36.0);
+  EXPECT_DOUBLE_EQ(function.Solve(0.25), 9.0 / 36.0);
+  EXPECT_DOUBLE_EQ(function.Solve(0.3), 10.0 / 36.0);
+  EXPECT_DOUBLE_EQ(function.Solve(0.35), 12.0 / 36.0);
+  EXPECT_DOUBLE_EQ(function.Solve(0.4), 14.0 / 36.0);
+  EXPECT_DOUBLE_EQ(function.Solve(0.45), 16.0 / 36.0);
+  EXPECT_DOUBLE_EQ(function.Solve(0.5), 18.0 / 36.0);
+  EXPECT_DOUBLE_EQ(function.Solve(0.55), 19.0 / 36.0);
+  EXPECT_DOUBLE_EQ(function.Solve(0.6), 21.0 / 36.0);
+  EXPECT_DOUBLE_EQ(function.Solve(0.65), 23.0 / 36.0);
+  EXPECT_DOUBLE_EQ(function.Solve(0.7), 25.0 / 36.0);
+  EXPECT_DOUBLE_EQ(function.Solve(0.75), 27.0 / 36.0);
+  EXPECT_DOUBLE_EQ(function.Solve(0.8), 28.0 / 36.0);
+  EXPECT_DOUBLE_EQ(function.Solve(0.85), 30.0 / 36.0);
+  EXPECT_DOUBLE_EQ(function.Solve(0.9), 32.0 / 36.0);
+  EXPECT_DOUBLE_EQ(function.Solve(0.95), 34.0 / 36.0);
+  EXPECT_DOUBLE_EQ(function.Solve(1.0), 1);
+  EXPECT_DOUBLE_EQ(function.Solve(2.0), 1);
+}
+
+TEST(StepsTest, StepsTimingFunctionStepsAtStart) {
+  Steps function(36, true);
+
+  EXPECT_DOUBLE_EQ(function.Solve(-1.0), 1.0 / 36.0);
+  EXPECT_DOUBLE_EQ(function.Solve(0), 1.0 / 36.0);
+  EXPECT_DOUBLE_EQ(function.Solve(0.05), 2.0 / 36.0);
+  EXPECT_DOUBLE_EQ(function.Solve(0.1), 4.0 / 36.0);
+  EXPECT_DOUBLE_EQ(function.Solve(0.15), 6.0 / 36.0);
+  EXPECT_DOUBLE_EQ(function.Solve(0.2), 8.0 / 36.0);
+  EXPECT_DOUBLE_EQ(function.Solve(0.25), 10.0 / 36.0);
+  EXPECT_DOUBLE_EQ(function.Solve(0.3), 11.0 / 36.0);
+  EXPECT_DOUBLE_EQ(function.Solve(0.35), 13.0 / 36.0);
+  EXPECT_DOUBLE_EQ(function.Solve(0.4), 15.0 / 36.0);
+  EXPECT_DOUBLE_EQ(function.Solve(0.45), 17.0 / 36.0);
+  EXPECT_DOUBLE_EQ(function.Solve(0.5), 19.0 / 36.0);
+  EXPECT_DOUBLE_EQ(function.Solve(0.6), 22.0 / 36.0);
+  EXPECT_DOUBLE_EQ(function.Solve(0.65), 24.0 / 36.0);
+  EXPECT_DOUBLE_EQ(function.Solve(0.7), 26.0 / 36.0);
+  EXPECT_DOUBLE_EQ(function.Solve(0.75), 28.0 / 36.0);
+  EXPECT_DOUBLE_EQ(function.Solve(0.8), 29.0 / 36.0);
+  EXPECT_DOUBLE_EQ(function.Solve(0.85), 31.0 / 36.0);
+  EXPECT_DOUBLE_EQ(function.Solve(0.9), 33.0 / 36.0);
+  EXPECT_DOUBLE_EQ(function.Solve(0.95), 35.0 / 36.0);
+  EXPECT_DOUBLE_EQ(function.Solve(1), 1);
+  EXPECT_DOUBLE_EQ(function.Solve(2.0), 1);
+}
+
+TEST(StepsTest, StepsTimingFunctionRange) {
+  double min, max;
+
+  Steps function1(36, false);
+
+  function1.Range(&min, &max);
+  EXPECT_DOUBLE_EQ(0.0, min);
+  EXPECT_DOUBLE_EQ(1.0, max);
+
+  Steps function2(36, true);
+  function2.Range(&min, &max);
+  EXPECT_DOUBLE_EQ(min, 1.0 / 36.0);
+  EXPECT_DOUBLE_EQ(1.0, max);
+}
+
+}  // namespace
+}  // namespace gfx