| // Copyright 2015 The Cobalt Authors. 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. |
| |
| #include <cmath> |
| |
| #include "cobalt/math/matrix_interpolation.h" |
| #include "cobalt/math/transform_2d.h" |
| #include "testing/gtest/include/gtest/gtest.h" |
| |
| namespace cobalt { |
| namespace math { |
| |
| namespace { |
| Matrix3F DecomposeAndRecompose(const Matrix3F& input) { |
| return RecomposeMatrix(DecomposeMatrix(input)); |
| } |
| } // namespace |
| |
| TEST(MatrixInterpolationTest, DecomposeAndRecomposeIsIdentityForXShear) { |
| Matrix3F input(Matrix3F::FromValues(1, 1, 0, 0, 1, 0, 0, 0, 1)); |
| |
| EXPECT_TRUE(input.IsNear(DecomposeAndRecompose(input), 0.001f)); |
| } |
| |
| TEST(MatrixInterpolationTest, DecomposeAndRecomposeIsIdentityForYShear) { |
| Matrix3F input(Matrix3F::FromValues(1, 0, 0, 1, 1, 0, 0, 0, 1)); |
| |
| EXPECT_TRUE(input.IsNear(DecomposeAndRecompose(input), 0.001f)); |
| } |
| |
| TEST(MatrixInterpolationTest, DecomposeAndRecomposeIsIdentityForRotation) { |
| Matrix3F input(RotateMatrix(static_cast<float>(M_PI / 4))); |
| |
| EXPECT_TRUE(input.IsNear(DecomposeAndRecompose(input), 0.001f)); |
| } |
| |
| TEST(MatrixInterpolationTest, DecomposeAndRecomposeIsIdentityForScale) { |
| Matrix3F input(ScaleMatrix(2.0f, 3.0f)); |
| |
| EXPECT_TRUE(input.IsNear(DecomposeAndRecompose(input), 0.001f)); |
| } |
| |
| TEST(MatrixInterpolationTest, DecomposeAndRecomposeIsIdentityForTranslation) { |
| Matrix3F input(TranslateMatrix(2.0f, 3.0f)); |
| |
| EXPECT_TRUE(input.IsNear(DecomposeAndRecompose(input), 0.001f)); |
| } |
| |
| TEST(MatrixInterpolationTest, |
| DecomposeAndRecomposeIsIdentityForShearAndTranslation) { |
| // The W3C specification multiplies the translation values by the shear values |
| // in matrix recomposition, but this is not how decomposition is done, and |
| // thus an exact implementation of their algorithm will fail this test. |
| // Failing this test (or any of these decompose and recompose tests) will |
| // result in jarring animations when transitioning from within a transition. |
| Matrix3F input(Matrix3F::FromValues(1, 1, 40, 0, 1, 40, 0, 0, 1)); |
| |
| EXPECT_TRUE(input.IsNear(DecomposeAndRecompose(input), 0.001f)); |
| } |
| |
| TEST(MatrixInterpolationTest, InterpolatingIdentitiesGivesIdentity) { |
| // We expect that interpolating two identity matrices will give us the |
| // identity matrix back. |
| Matrix3F a(Matrix3F::Identity()); |
| Matrix3F b(Matrix3F::Identity()); |
| |
| static const int kNumSamples = 10; |
| for (int i = 0; i < kNumSamples + 1; ++i) { |
| math::Matrix3F interpolated = |
| InterpolateMatrices(a, b, i / static_cast<float>(kNumSamples)); |
| EXPECT_EQ(Matrix3F::Identity(), interpolated); |
| } |
| } |
| |
| } // namespace math |
| } // namespace cobalt |