Scroll offset animation curve retargeting.

cc/animation/scroll_offset_animation_curve_unittest.cc

 // Copyright 2013 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 "cc/animation/scroll_offset_animation_curve.h"
 
 #include "cc/animation/timing_function.h"
 #include "cc/test/geometry_test_utils.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
@@ skipping 101 matching lines @@
       target_value,
       clone->ToScrollOffsetAnimationCurve()->GetValue(duration + 1.0));
 
   // Verify that the timing function was cloned correctly.
   gfx::Vector2dF value =
       clone->ToScrollOffsetAnimationCurve()->GetValue(duration / 4.0);
   EXPECT_NEAR(3.0333f, value.x(), 0.00015f);
   EXPECT_NEAR(37.4168f, value.y(), 0.00015f);
 }
 
+TEST(ScrollOffsetAnimationCurveTest, UpdateTarget) {
+  gfx::Vector2dF initial_value(0.f, 0.f);
+  gfx::Vector2dF target_value(0.f, 3600.f);
+  scoped_ptr<ScrollOffsetAnimationCurve> curve(
+      ScrollOffsetAnimationCurve::Create(
+          target_value, EaseInOutTimingFunction::Create().Pass()));
+  curve->SetInitialValue(initial_value);
+  EXPECT_EQ(1.0, curve->Duration());
+  EXPECT_EQ(1800.0, curve->GetValue(0.5).y());
+  EXPECT_EQ(3600.0, curve->GetValue(1.0).y());
+
+  curve->UpdateTarget(0.5, gfx::Vector2dF(0.0, 9900.0));
+
+  EXPECT_EQ(2.0, curve->Duration());
+  EXPECT_EQ(1800.0, curve->GetValue(0.5).y());
+  EXPECT_NEAR(5566.49, curve->GetValue(1.0).y(), 0.01);
+  EXPECT_EQ(9900.0, curve->GetValue(2.0).y());

[ajuma, 2014/07/16 20:35:23]

Please add one more re-targeting here (to verify that an already-retargeted
curve gets re-targeted again correctly).

[skobes, 2014/07/16 21:10:48]

Done.

+}
+
 }  // namespace
 }  // namespace cc