AUtils.h revision c416becd966945fca5fa7fb45ac51f84d1d8cd20
1c416becd966945fca5fa7fb45ac51f84d1d8cd20Lajos Molnar/*
2c416becd966945fca5fa7fb45ac51f84d1d8cd20Lajos Molnar * Copyright 2014 The Android Open Source Project
3c416becd966945fca5fa7fb45ac51f84d1d8cd20Lajos Molnar *
4c416becd966945fca5fa7fb45ac51f84d1d8cd20Lajos Molnar * Licensed under the Apache License, Version 2.0 (the "License");
5c416becd966945fca5fa7fb45ac51f84d1d8cd20Lajos Molnar * you may not use this file except in compliance with the License.
6c416becd966945fca5fa7fb45ac51f84d1d8cd20Lajos Molnar * You may obtain a copy of the License at
7c416becd966945fca5fa7fb45ac51f84d1d8cd20Lajos Molnar *
8c416becd966945fca5fa7fb45ac51f84d1d8cd20Lajos Molnar *      http://www.apache.org/licenses/LICENSE-2.0
9c416becd966945fca5fa7fb45ac51f84d1d8cd20Lajos Molnar *
10c416becd966945fca5fa7fb45ac51f84d1d8cd20Lajos Molnar * Unless required by applicable law or agreed to in writing, software
11c416becd966945fca5fa7fb45ac51f84d1d8cd20Lajos Molnar * distributed under the License is distributed on an "AS IS" BASIS,
12c416becd966945fca5fa7fb45ac51f84d1d8cd20Lajos Molnar * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13c416becd966945fca5fa7fb45ac51f84d1d8cd20Lajos Molnar * See the License for the specific language governing permissions and
14c416becd966945fca5fa7fb45ac51f84d1d8cd20Lajos Molnar * limitations under the License.
15c416becd966945fca5fa7fb45ac51f84d1d8cd20Lajos Molnar */
16c416becd966945fca5fa7fb45ac51f84d1d8cd20Lajos Molnar
17c416becd966945fca5fa7fb45ac51f84d1d8cd20Lajos Molnar#ifndef A_UTILS_H_
18c416becd966945fca5fa7fb45ac51f84d1d8cd20Lajos Molnar
19c416becd966945fca5fa7fb45ac51f84d1d8cd20Lajos Molnar#define A_UTILS_H_
20c416becd966945fca5fa7fb45ac51f84d1d8cd20Lajos Molnar
21c416becd966945fca5fa7fb45ac51f84d1d8cd20Lajos Molnar/* ============================ math templates ============================ */
22c416becd966945fca5fa7fb45ac51f84d1d8cd20Lajos Molnar
23c416becd966945fca5fa7fb45ac51f84d1d8cd20Lajos Molnar/* T must be integer type, den must not be 0 */
24c416becd966945fca5fa7fb45ac51f84d1d8cd20Lajos Molnartemplate<class T>
25c416becd966945fca5fa7fb45ac51f84d1d8cd20Lajos Molnarinline static const T divRound(const T &nom, const T &den) {
26c416becd966945fca5fa7fb45ac51f84d1d8cd20Lajos Molnar    if ((nom >= 0) ^ (den >= 0)) {
27c416becd966945fca5fa7fb45ac51f84d1d8cd20Lajos Molnar        return (nom - den / 2) / den;
28c416becd966945fca5fa7fb45ac51f84d1d8cd20Lajos Molnar    } else {
29c416becd966945fca5fa7fb45ac51f84d1d8cd20Lajos Molnar        return (nom + den / 2) / den;
30c416becd966945fca5fa7fb45ac51f84d1d8cd20Lajos Molnar    }
31c416becd966945fca5fa7fb45ac51f84d1d8cd20Lajos Molnar}
32c416becd966945fca5fa7fb45ac51f84d1d8cd20Lajos Molnar
33c416becd966945fca5fa7fb45ac51f84d1d8cd20Lajos Molnar/* == ceil(nom / den). T must be integer type, den must not be 0 */
34c416becd966945fca5fa7fb45ac51f84d1d8cd20Lajos Molnartemplate<class T>
35c416becd966945fca5fa7fb45ac51f84d1d8cd20Lajos Molnarinline static const T divUp(const T &nom, const T &den) {
36c416becd966945fca5fa7fb45ac51f84d1d8cd20Lajos Molnar    if (den < 0) {
37c416becd966945fca5fa7fb45ac51f84d1d8cd20Lajos Molnar        return (nom < 0 ? nom + den + 1 : nom) / den;
38c416becd966945fca5fa7fb45ac51f84d1d8cd20Lajos Molnar    } else {
39c416becd966945fca5fa7fb45ac51f84d1d8cd20Lajos Molnar        return (nom < 0 ? nom : nom + den - 1) / den;
40c416becd966945fca5fa7fb45ac51f84d1d8cd20Lajos Molnar    }
41c416becd966945fca5fa7fb45ac51f84d1d8cd20Lajos Molnar}
42c416becd966945fca5fa7fb45ac51f84d1d8cd20Lajos Molnar
43c416becd966945fca5fa7fb45ac51f84d1d8cd20Lajos Molnartemplate<class T>
44c416becd966945fca5fa7fb45ac51f84d1d8cd20Lajos Molnarinline static T abs(const T &a) {
45c416becd966945fca5fa7fb45ac51f84d1d8cd20Lajos Molnar    return a < 0 ? -a : a;
46c416becd966945fca5fa7fb45ac51f84d1d8cd20Lajos Molnar}
47c416becd966945fca5fa7fb45ac51f84d1d8cd20Lajos Molnar
48c416becd966945fca5fa7fb45ac51f84d1d8cd20Lajos Molnartemplate<class T>
49c416becd966945fca5fa7fb45ac51f84d1d8cd20Lajos Molnarinline static const T &min(const T &a, const T &b) {
50c416becd966945fca5fa7fb45ac51f84d1d8cd20Lajos Molnar    return a < b ? a : b;
51c416becd966945fca5fa7fb45ac51f84d1d8cd20Lajos Molnar}
52c416becd966945fca5fa7fb45ac51f84d1d8cd20Lajos Molnar
53c416becd966945fca5fa7fb45ac51f84d1d8cd20Lajos Molnartemplate<class T>
54c416becd966945fca5fa7fb45ac51f84d1d8cd20Lajos Molnarinline static const T &max(const T &a, const T &b) {
55c416becd966945fca5fa7fb45ac51f84d1d8cd20Lajos Molnar    return a > b ? a : b;
56c416becd966945fca5fa7fb45ac51f84d1d8cd20Lajos Molnar}
57c416becd966945fca5fa7fb45ac51f84d1d8cd20Lajos Molnar
58c416becd966945fca5fa7fb45ac51f84d1d8cd20Lajos Molnar/* T must be integer type, period must be positive */
59c416becd966945fca5fa7fb45ac51f84d1d8cd20Lajos Molnartemplate<class T>
60c416becd966945fca5fa7fb45ac51f84d1d8cd20Lajos Molnarinline static T periodicError(const T &val, const T &period) {
61c416becd966945fca5fa7fb45ac51f84d1d8cd20Lajos Molnar    T err = abs(val) % period;
62c416becd966945fca5fa7fb45ac51f84d1d8cd20Lajos Molnar    return (err < (period / 2)) ? err : (period - err);
63c416becd966945fca5fa7fb45ac51f84d1d8cd20Lajos Molnar}
64c416becd966945fca5fa7fb45ac51f84d1d8cd20Lajos Molnar
65c416becd966945fca5fa7fb45ac51f84d1d8cd20Lajos Molnar#endif  // A_UTILS_H_
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