diff options
| author | vollick@chromium.org <vollick@chromium.org@0039d316-1c4b-4281-b951-d872f2087c98> | 2013-05-29 02:52:25 +0000 |
|---|---|---|
| committer | vollick@chromium.org <vollick@chromium.org@0039d316-1c4b-4281-b951-d872f2087c98> | 2013-05-29 02:52:25 +0000 |
| commit | 6b1d558a80d80528df4f86d75b2a43a26f3e2487 (patch) | |
| tree | a8ed97f25c16f946a9d969ac70340d2c03bae267 /cc/animation/timing_function_unittest.cc | |
| parent | c40df01c49515eea3e9ee37bc82b644c778ee25e (diff) | |
| download | chromium_src-6b1d558a80d80528df4f86d75b2a43a26f3e2487.zip chromium_src-6b1d558a80d80528df4f86d75b2a43a26f3e2487.tar.gz chromium_src-6b1d558a80d80528df4f86d75b2a43a26f3e2487.tar.bz2 | |
Do not clamp y values on internal knots of timing function bezier curves
Cubic bezier timing functions are based on two knots (x1, y1) and (x2, y2) (the
other knots are assumed to be (0, 0) and (1, 1)). We require that x1, x2 lie
within (0, 1) (so that the bezier does not 'fold back' on itself), but y1, and
y2 should have no such constraint. They currently do. This CL reimplements
bezier interpolation without this restriction. This interpolation has two steps:
1) Find the t corresponding to the desired x.
2) Interpolate y's at the t computed in step 1.
Step 1 is an iterative minimization. Here I do bisection for simplicity, but I
could take Newton steps if this turns out to be a bottleneck.
R=ajuma@chromium.org
BUG=178070
Review URL: https://chromiumcodereview.appspot.com/16112002
git-svn-id: svn://svn.chromium.org/chrome/trunk/src@202755 0039d316-1c4b-4281-b951-d872f2087c98
Diffstat (limited to 'cc/animation/timing_function_unittest.cc')
| -rw-r--r-- | cc/animation/timing_function_unittest.cc | 30 |
1 files changed, 30 insertions, 0 deletions
diff --git a/cc/animation/timing_function_unittest.cc b/cc/animation/timing_function_unittest.cc index c076d52..2caa12d 100644 --- a/cc/animation/timing_function_unittest.cc +++ b/cc/animation/timing_function_unittest.cc @@ -37,5 +37,35 @@ TEST(TimingFunctionTest, CubicBezierTimingFunction) { EXPECT_NEAR(function->GetValue(1), 1, epsilon); } +// Tests that the bezier timing function works with knots with y not in (0, 1). +TEST(TimingFunctionTest, CubicBezierTimingFunctionUnclampedYValues) { + scoped_ptr<CubicBezierTimingFunction> function = + CubicBezierTimingFunction::Create(0.5, -1.0, 0.5, 2.0); + + double epsilon = 0.00015; + + EXPECT_NEAR(function->GetValue(0.0), 0.0, epsilon); + EXPECT_NEAR(function->GetValue(0.05), -0.08954, epsilon); + EXPECT_NEAR(function->GetValue(0.1), -0.15613, epsilon); + EXPECT_NEAR(function->GetValue(0.15), -0.19641, epsilon); + EXPECT_NEAR(function->GetValue(0.2), -0.20651, epsilon); + EXPECT_NEAR(function->GetValue(0.25), -0.18232, epsilon); + EXPECT_NEAR(function->GetValue(0.3), -0.11992, epsilon); + EXPECT_NEAR(function->GetValue(0.35), -0.01672, epsilon); + EXPECT_NEAR(function->GetValue(0.4), 0.12660, epsilon); + EXPECT_NEAR(function->GetValue(0.45), 0.30349, epsilon); + EXPECT_NEAR(function->GetValue(0.5), 0.50000, epsilon); + EXPECT_NEAR(function->GetValue(0.55), 0.69651, epsilon); + EXPECT_NEAR(function->GetValue(0.6), 0.87340, epsilon); + EXPECT_NEAR(function->GetValue(0.65), 1.01672, epsilon); + EXPECT_NEAR(function->GetValue(0.7), 1.11992, epsilon); + EXPECT_NEAR(function->GetValue(0.75), 1.18232, epsilon); + EXPECT_NEAR(function->GetValue(0.8), 1.20651, epsilon); + EXPECT_NEAR(function->GetValue(0.85), 1.19641, epsilon); + EXPECT_NEAR(function->GetValue(0.9), 1.15613, epsilon); + EXPECT_NEAR(function->GetValue(0.95), 1.08954, epsilon); + EXPECT_NEAR(function->GetValue(1.0), 1.0, epsilon); +} + } // namespace } // namespace cc |