Home | History | Annotate | Download | only in geometry
      1 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
      2 // Use of this source code is governed by a BSD-style license that can be
      3 // found in the LICENSE file.
      4 
      5 #include <cmath>
      6 #include <limits>
      7 
      8 #include "base/basictypes.h"
      9 #include "testing/gtest/include/gtest/gtest.h"
     10 #include "ui/gfx/geometry/matrix3_f.h"
     11 
     12 namespace gfx {
     13 namespace {
     14 
     15 TEST(Matrix3fTest, Constructors) {
     16   Matrix3F zeros = Matrix3F::Zeros();
     17   Matrix3F ones = Matrix3F::Ones();
     18   Matrix3F identity = Matrix3F::Identity();
     19 
     20   Matrix3F product_ones = Matrix3F::FromOuterProduct(
     21       Vector3dF(1.0f, 1.0f, 1.0f), Vector3dF(1.0f, 1.0f, 1.0f));
     22   Matrix3F product_zeros = Matrix3F::FromOuterProduct(
     23       Vector3dF(1.0f, 1.0f, 1.0f), Vector3dF(0.0f, 0.0f, 0.0f));
     24   EXPECT_EQ(ones, product_ones);
     25   EXPECT_EQ(zeros, product_zeros);
     26 
     27   for (int i = 0; i < 3; ++i) {
     28     for (int j = 0; j < 3; ++j)
     29       EXPECT_EQ(i == j ? 1.0f : 0.0f, identity.get(i, j));
     30   }
     31 }
     32 
     33 TEST(Matrix3fTest, DataAccess) {
     34   Matrix3F matrix = Matrix3F::Ones();
     35   Matrix3F identity = Matrix3F::Identity();
     36 
     37   EXPECT_EQ(Vector3dF(0.0f, 1.0f, 0.0f), identity.get_column(1));
     38   matrix.set(0.0f, 1.0f, 2.0f, 3.0f, 4.0f, 5.0f, 6.0f, 7.0f, 8.0f);
     39   EXPECT_EQ(Vector3dF(2.0f, 5.0f, 8.0f), matrix.get_column(2));
     40   matrix.set_column(0, Vector3dF(0.1f, 0.2f, 0.3f));
     41   EXPECT_EQ(Vector3dF(0.1f, 0.2f, 0.3f), matrix.get_column(0));
     42 
     43   EXPECT_EQ(0.1f, matrix.get(0, 0));
     44   EXPECT_EQ(5.0f, matrix.get(1, 2));
     45 }
     46 
     47 TEST(Matrix3fTest, Determinant) {
     48   EXPECT_EQ(1.0f, Matrix3F::Identity().Determinant());
     49   EXPECT_EQ(0.0f, Matrix3F::Zeros().Determinant());
     50   EXPECT_EQ(0.0f, Matrix3F::Ones().Determinant());
     51 
     52   // Now for something non-trivial...
     53   Matrix3F matrix = Matrix3F::Zeros();
     54   matrix.set(0, 5, 6, 8, 7, 0, 1, 9, 0);
     55   EXPECT_EQ(390.0f, matrix.Determinant());
     56   matrix.set(2, 0, 3 * matrix.get(0, 0));
     57   matrix.set(2, 1, 3 * matrix.get(0, 1));
     58   matrix.set(2, 2, 3 * matrix.get(0, 2));
     59   EXPECT_EQ(0, matrix.Determinant());
     60 
     61   matrix.set(0.57f,  0.205f,  0.942f,
     62              0.314f,  0.845f,  0.826f,
     63              0.131f,  0.025f,  0.962f);
     64   EXPECT_NEAR(0.3149f, matrix.Determinant(), 0.0001f);
     65 }
     66 
     67 TEST(Matrix3fTest, Inverse) {
     68   Matrix3F identity = Matrix3F::Identity();
     69   Matrix3F inv_identity = identity.Inverse();
     70   EXPECT_EQ(identity, inv_identity);
     71 
     72   Matrix3F singular = Matrix3F::Zeros();
     73   singular.set(1.0f, 3.0f, 4.0f,
     74                2.0f, 11.0f, 5.0f,
     75                0.5f, 1.5f, 2.0f);
     76   EXPECT_EQ(0, singular.Determinant());
     77   EXPECT_EQ(Matrix3F::Zeros(), singular.Inverse());
     78 
     79   Matrix3F regular = Matrix3F::Zeros();
     80   regular.set(0.57f,  0.205f,  0.942f,
     81               0.314f,  0.845f,  0.826f,
     82               0.131f,  0.025f,  0.962f);
     83   Matrix3F inv_regular = regular.Inverse();
     84   regular.set(2.51540616f, -0.55138018f, -1.98968043f,
     85               -0.61552266f,  1.34920184f, -0.55573636f,
     86               -0.32653861f,  0.04002158f,  1.32488726f);
     87   EXPECT_TRUE(regular.IsNear(inv_regular, 0.00001f));
     88 }
     89 
     90 TEST(Matrix3fTest, EigenvectorsIdentity) {
     91   // This block tests the trivial case of eigenvalues of the identity matrix.
     92   Matrix3F identity = Matrix3F::Identity();
     93   Vector3dF eigenvals = identity.SolveEigenproblem(NULL);
     94   EXPECT_EQ(Vector3dF(1.0f, 1.0f, 1.0f), eigenvals);
     95 }
     96 
     97 TEST(Matrix3fTest, EigenvectorsDiagonal)  {
     98   // This block tests the another trivial case of eigenvalues of a diagonal
     99   // matrix. Here we expect values to be sorted.
    100   Matrix3F matrix = Matrix3F::Zeros();
    101   matrix.set(0, 0, 1.0f);
    102   matrix.set(1, 1, -2.5f);
    103   matrix.set(2, 2, 3.14f);
    104   Matrix3F eigenvectors = Matrix3F::Zeros();
    105   Vector3dF eigenvals = matrix.SolveEigenproblem(&eigenvectors);
    106   EXPECT_EQ(Vector3dF(3.14f, 1.0f, -2.5f), eigenvals);
    107 
    108   EXPECT_EQ(Vector3dF(0.0f, 0.0f, 1.0f), eigenvectors.get_column(0));
    109   EXPECT_EQ(Vector3dF(1.0f, 0.0f, 0.0f), eigenvectors.get_column(1));
    110   EXPECT_EQ(Vector3dF(0.0f, 1.0f, 0.0f), eigenvectors.get_column(2));
    111 }
    112 
    113 TEST(Matrix3fTest, EigenvectorsNiceNotPositive)  {
    114   // This block tests computation of eigenvectors of a matrix where nice
    115   // round values are expected.
    116   Matrix3F matrix = Matrix3F::Zeros();
    117   // This is not a positive-definite matrix but eigenvalues and the first
    118   // eigenvector should nonetheless be computed correctly.
    119   matrix.set(3, 2, 4, 2, 0, 2, 4, 2, 3);
    120   Matrix3F eigenvectors = Matrix3F::Zeros();
    121   Vector3dF eigenvals = matrix.SolveEigenproblem(&eigenvectors);
    122   EXPECT_EQ(Vector3dF(8.0f, -1.0f, -1.0f), eigenvals);
    123 
    124   Vector3dF expected_principal(0.66666667f, 0.33333333f, 0.66666667f);
    125   EXPECT_NEAR(0.0f,
    126               (expected_principal - eigenvectors.get_column(0)).Length(),
    127               0.000001f);
    128 }
    129 
    130 TEST(Matrix3fTest, EigenvectorsPositiveDefinite) {
    131   // This block tests computation of eigenvectors of a matrix where output
    132   // is not as nice as above, but it actually meets the definition.
    133   Matrix3F matrix = Matrix3F::Zeros();
    134   Matrix3F eigenvectors = Matrix3F::Zeros();
    135   Matrix3F expected_eigenvectors = Matrix3F::Zeros();
    136   matrix.set(1, -1,  2, -1,  4,  5, 2,  5,  0);
    137   Vector3dF eigenvals =  matrix.SolveEigenproblem(&eigenvectors);
    138   Vector3dF expected_eigv(7.3996266f, 1.91197255f, -4.31159915f);
    139   expected_eigv -= eigenvals;
    140   EXPECT_NEAR(0, expected_eigv.LengthSquared(), 0.00001f);
    141   expected_eigenvectors.set(0.04926317f, -0.92135662f, -0.38558414f,
    142                             0.82134249f, 0.25703273f, -0.50924521f,
    143                             0.56830419f, -0.2916096f, 0.76941158f);
    144   EXPECT_TRUE(expected_eigenvectors.IsNear(eigenvectors, 0.00001f));
    145 }
    146 
    147 }
    148 }
    149