1 /* 2 * Copyright 2014 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 A_UTILS_H_ 18 19 #define A_UTILS_H_ 20 21 /* ============================ math templates ============================ */ 22 23 /* T must be integer type, den must not be 0 */ 24 template<class T> 25 inline static const T divRound(const T &nom, const T &den) { 26 if ((nom >= 0) ^ (den >= 0)) { 27 return (nom - den / 2) / den; 28 } else { 29 return (nom + den / 2) / den; 30 } 31 } 32 33 /* == ceil(nom / den). T must be integer type, den must not be 0 */ 34 template<class T> 35 inline static const T divUp(const T &nom, const T &den) { 36 if (den < 0) { 37 return (nom < 0 ? nom + den + 1 : nom) / den; 38 } else { 39 return (nom < 0 ? nom : nom + den - 1) / den; 40 } 41 } 42 43 template<class T> 44 inline static T abs(const T &a) { 45 return a < 0 ? -a : a; 46 } 47 48 template<class T> 49 inline static const T &min(const T &a, const T &b) { 50 return a < b ? a : b; 51 } 52 53 template<class T> 54 inline static const T &max(const T &a, const T &b) { 55 return a > b ? a : b; 56 } 57 58 /* T must be integer type, period must be positive */ 59 template<class T> 60 inline static T periodicError(const T &val, const T &period) { 61 T err = abs(val) % period; 62 return (err < (period / 2)) ? err : (period - err); 63 } 64 65 #endif // A_UTILS_H_ 66
