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 #ifndef UI_GFX_GEOMETRY_MATRIX3_F_H_ 6 #define UI_GFX_GEOMETRY_MATRIX3_F_H_ 7 8 #include "base/logging.h" 9 #include "ui/gfx/geometry/vector3d_f.h" 10 11 namespace gfx { 12 13 class GFX_EXPORT Matrix3F { 14 public: 15 ~Matrix3F(); 16 17 static Matrix3F Zeros(); 18 static Matrix3F Ones(); 19 static Matrix3F Identity(); 20 static Matrix3F FromOuterProduct(const Vector3dF& a, const Vector3dF& bt); 21 22 bool IsEqual(const Matrix3F& rhs) const; 23 24 // Element-wise comparison with given precision. 25 bool IsNear(const Matrix3F& rhs, float precision) const; 26 27 float get(int i, int j) const { 28 return data_[MatrixToArrayCoords(i, j)]; 29 } 30 31 void set(int i, int j, float v) { 32 data_[MatrixToArrayCoords(i, j)] = v; 33 } 34 35 void set(float m00, float m01, float m02, 36 float m10, float m11, float m12, 37 float m20, float m21, float m22) { 38 data_[0] = m00; 39 data_[1] = m01; 40 data_[2] = m02; 41 data_[3] = m10; 42 data_[4] = m11; 43 data_[5] = m12; 44 data_[6] = m20; 45 data_[7] = m21; 46 data_[8] = m22; 47 } 48 49 Vector3dF get_column(int i) const { 50 return Vector3dF( 51 data_[MatrixToArrayCoords(0, i)], 52 data_[MatrixToArrayCoords(1, i)], 53 data_[MatrixToArrayCoords(2, i)]); 54 } 55 56 void set_column(int i, const Vector3dF& c) { 57 data_[MatrixToArrayCoords(0, i)] = c.x(); 58 data_[MatrixToArrayCoords(1, i)] = c.y(); 59 data_[MatrixToArrayCoords(2, i)] = c.z(); 60 } 61 62 // Returns an inverse of this if the matrix is non-singular, zero (== Zero()) 63 // otherwise. 64 Matrix3F Inverse() const; 65 66 // Value of the determinant of the matrix. 67 float Determinant() const; 68 69 // Trace (sum of diagonal elements) of the matrix. 70 float Trace() const { 71 return data_[MatrixToArrayCoords(0, 0)] + 72 data_[MatrixToArrayCoords(1, 1)] + 73 data_[MatrixToArrayCoords(2, 2)]; 74 } 75 76 // Compute eigenvalues and (optionally) normalized eigenvectors of 77 // a positive defnite matrix *this. Eigenvectors are computed only if 78 // non-null |eigenvectors| matrix is passed. If it is NULL, the routine 79 // will not attempt to compute eigenvectors but will still return eigenvalues 80 // if they can be computed. 81 // If eigenvalues cannot be computed (the matrix does not meet constraints) 82 // the 0-vector is returned. Note that to retrieve eigenvalues, the matrix 83 // only needs to be symmetric while eigenvectors require it to be 84 // positive-definite. Passing a non-positive definite matrix will result in 85 // NaNs in vectors which cannot be computed. 86 // Eigenvectors are placed as column in |eigenvectors| in order corresponding 87 // to eigenvalues. 88 Vector3dF SolveEigenproblem(Matrix3F* eigenvectors) const; 89 90 private: 91 Matrix3F(); // Uninitialized default. 92 93 static int MatrixToArrayCoords(int i, int j) { 94 DCHECK(i >= 0 && i < 3); 95 DCHECK(j >= 0 && j < 3); 96 return i * 3 + j; 97 } 98 99 float data_[9]; 100 }; 101 102 inline bool operator==(const Matrix3F& lhs, const Matrix3F& rhs) { 103 return lhs.IsEqual(rhs); 104 } 105 106 } // namespace gfx 107 108 #endif // UI_GFX_GEOMETRY_MATRIX3_F_H_ 109
