| // Copyright 2019 The Chromium Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #include "pdf/page_orientation.h" |
| |
| #include <type_traits> |
| |
| namespace chrome_pdf { |
| |
| namespace { |
| |
| // Adds two PageOrientation values together. This works because the underlying |
| // integer values have been chosen to allow modular arithmetic. |
| PageOrientation AddOrientations(PageOrientation first, PageOrientation second) { |
| using IntType = std::underlying_type<PageOrientation>::type; |
| |
| constexpr auto kOrientationCount = |
| static_cast<IntType>(PageOrientation::kLast) + 1; |
| |
| auto first_int = static_cast<IntType>(first); |
| auto second_int = static_cast<IntType>(second); |
| return static_cast<PageOrientation>((first_int + second_int) % |
| kOrientationCount); |
| } |
| |
| } // namespace |
| |
| PageOrientation RotateClockwise(PageOrientation orientation) { |
| return AddOrientations(orientation, PageOrientation::kClockwise90); |
| } |
| |
| PageOrientation RotateCounterclockwise(PageOrientation orientation) { |
| // Adding |kLast| is equivalent to rotating one step counterclockwise. |
| return AddOrientations(orientation, PageOrientation::kLast); |
| } |
| |
| } // namespace chrome_pdf |