Mathias Agopian | 595ea77 | 2013-08-21 23:10:41 -0700 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright 2013 The Android Open Source Project |
| 3 | * |
| 4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 5 | * you may not use this file except in compliance with the License. |
| 6 | * You may obtain a copy of the License at |
| 7 | * |
| 8 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 9 | * |
| 10 | * Unless required by applicable law or agreed to in writing, software |
| 11 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 13 | * See the License for the specific language governing permissions and |
| 14 | * limitations under the License. |
| 15 | */ |
| 16 | |
| 17 | #ifndef TMAT_IMPLEMENTATION |
| 18 | #error "Don't include TMatHelpers.h directly. use ui/mat*.h instead" |
| 19 | #else |
| 20 | #undef TMAT_IMPLEMENTATION |
| 21 | #endif |
| 22 | |
| 23 | |
| 24 | #ifndef UI_TMAT_HELPERS_H |
| 25 | #define UI_TMAT_HELPERS_H |
| 26 | |
| 27 | #include <stdint.h> |
| 28 | #include <sys/types.h> |
| 29 | #include <utils/Debug.h> |
| 30 | #include <utils/String8.h> |
| 31 | |
| 32 | #define PURE __attribute__((pure)) |
| 33 | |
| 34 | namespace android { |
| 35 | // ------------------------------------------------------------------------------------- |
| 36 | |
| 37 | /* |
| 38 | * No user serviceable parts here. |
| 39 | * |
| 40 | * Don't use this file directly, instead include ui/mat*.h |
| 41 | */ |
| 42 | |
| 43 | |
| 44 | /* |
| 45 | * Matrix utilities |
| 46 | */ |
| 47 | |
| 48 | namespace matrix { |
| 49 | |
| 50 | inline int PURE transpose(int v) { return v; } |
| 51 | inline float PURE transpose(float v) { return v; } |
| 52 | inline double PURE transpose(double v) { return v; } |
| 53 | |
| 54 | inline int PURE trace(int v) { return v; } |
| 55 | inline float PURE trace(float v) { return v; } |
| 56 | inline double PURE trace(double v) { return v; } |
| 57 | |
| 58 | template<typename MATRIX> |
| 59 | MATRIX PURE inverse(const MATRIX& src) { |
| 60 | |
| 61 | COMPILE_TIME_ASSERT_FUNCTION_SCOPE( MATRIX::COL_SIZE == MATRIX::ROW_SIZE ); |
| 62 | |
| 63 | typename MATRIX::value_type t; |
| 64 | const size_t N = MATRIX::col_size(); |
| 65 | size_t swap; |
| 66 | MATRIX tmp(src); |
| 67 | MATRIX inverse(1); |
| 68 | |
| 69 | for (size_t i=0 ; i<N ; i++) { |
| 70 | // look for largest element in column |
| 71 | swap = i; |
| 72 | for (size_t j=i+1 ; j<N ; j++) { |
| 73 | if (fabs(tmp[j][i]) > fabs(tmp[i][i])) { |
| 74 | swap = j; |
| 75 | } |
| 76 | } |
| 77 | |
| 78 | if (swap != i) { |
| 79 | /* swap rows. */ |
| 80 | for (size_t k=0 ; k<N ; k++) { |
| 81 | t = tmp[i][k]; |
| 82 | tmp[i][k] = tmp[swap][k]; |
| 83 | tmp[swap][k] = t; |
| 84 | |
| 85 | t = inverse[i][k]; |
| 86 | inverse[i][k] = inverse[swap][k]; |
| 87 | inverse[swap][k] = t; |
| 88 | } |
| 89 | } |
| 90 | |
| 91 | t = 1 / tmp[i][i]; |
| 92 | for (size_t k=0 ; k<N ; k++) { |
| 93 | tmp[i][k] *= t; |
| 94 | inverse[i][k] *= t; |
| 95 | } |
| 96 | for (size_t j=0 ; j<N ; j++) { |
| 97 | if (j != i) { |
| 98 | t = tmp[j][i]; |
| 99 | for (size_t k=0 ; k<N ; k++) { |
| 100 | tmp[j][k] -= tmp[i][k] * t; |
| 101 | inverse[j][k] -= inverse[i][k] * t; |
| 102 | } |
| 103 | } |
| 104 | } |
| 105 | } |
| 106 | return inverse; |
| 107 | } |
| 108 | |
| 109 | template<typename MATRIX_R, typename MATRIX_A, typename MATRIX_B> |
| 110 | MATRIX_R PURE multiply(const MATRIX_A& lhs, const MATRIX_B& rhs) { |
| 111 | // pre-requisite: |
| 112 | // lhs : D columns, R rows |
| 113 | // rhs : C columns, D rows |
| 114 | // res : C columns, R rows |
| 115 | |
| 116 | COMPILE_TIME_ASSERT_FUNCTION_SCOPE( MATRIX_A::ROW_SIZE == MATRIX_B::COL_SIZE ); |
| 117 | COMPILE_TIME_ASSERT_FUNCTION_SCOPE( MATRIX_R::ROW_SIZE == MATRIX_B::ROW_SIZE ); |
| 118 | COMPILE_TIME_ASSERT_FUNCTION_SCOPE( MATRIX_R::COL_SIZE == MATRIX_A::COL_SIZE ); |
| 119 | |
| 120 | MATRIX_R res(MATRIX_R::NO_INIT); |
| 121 | for (size_t r=0 ; r<MATRIX_R::row_size() ; r++) { |
| 122 | res[r] = lhs * rhs[r]; |
| 123 | } |
| 124 | return res; |
| 125 | } |
| 126 | |
| 127 | // transpose. this handles matrices of matrices |
| 128 | template <typename MATRIX> |
| 129 | MATRIX PURE transpose(const MATRIX& m) { |
| 130 | // for now we only handle square matrix transpose |
| 131 | COMPILE_TIME_ASSERT_FUNCTION_SCOPE( MATRIX::ROW_SIZE == MATRIX::COL_SIZE ); |
| 132 | MATRIX result(MATRIX::NO_INIT); |
| 133 | for (size_t r=0 ; r<MATRIX::row_size() ; r++) |
| 134 | for (size_t c=0 ; c<MATRIX::col_size() ; c++) |
| 135 | result[c][r] = transpose(m[r][c]); |
| 136 | return result; |
| 137 | } |
| 138 | |
| 139 | // trace. this handles matrices of matrices |
| 140 | template <typename MATRIX> |
| 141 | typename MATRIX::value_type PURE trace(const MATRIX& m) { |
| 142 | COMPILE_TIME_ASSERT_FUNCTION_SCOPE( MATRIX::ROW_SIZE == MATRIX::COL_SIZE ); |
| 143 | typename MATRIX::value_type result(0); |
| 144 | for (size_t r=0 ; r<MATRIX::row_size() ; r++) |
| 145 | result += trace(m[r][r]); |
| 146 | return result; |
| 147 | } |
| 148 | |
| 149 | // trace. this handles matrices of matrices |
| 150 | template <typename MATRIX> |
| 151 | typename MATRIX::col_type PURE diag(const MATRIX& m) { |
| 152 | COMPILE_TIME_ASSERT_FUNCTION_SCOPE( MATRIX::ROW_SIZE == MATRIX::COL_SIZE ); |
| 153 | typename MATRIX::col_type result(MATRIX::col_type::NO_INIT); |
| 154 | for (size_t r=0 ; r<MATRIX::row_size() ; r++) |
| 155 | result[r] = m[r][r]; |
| 156 | return result; |
| 157 | } |
| 158 | |
| 159 | template <typename MATRIX> |
| 160 | String8 asString(const MATRIX& m) { |
| 161 | String8 s; |
| 162 | for (size_t c=0 ; c<MATRIX::col_size() ; c++) { |
| 163 | s.append("| "); |
| 164 | for (size_t r=0 ; r<MATRIX::row_size() ; r++) { |
| 165 | s.appendFormat("%7.2f ", m[r][c]); |
| 166 | } |
| 167 | s.append("|\n"); |
| 168 | } |
| 169 | return s; |
| 170 | } |
| 171 | |
| 172 | }; // namespace matrix |
| 173 | |
| 174 | // ------------------------------------------------------------------------------------- |
| 175 | }; // namespace android |
| 176 | |
| 177 | #undef PURE |
| 178 | |
| 179 | #endif /* UI_TMAT_HELPERS_H */ |