| /* |
| * Copyright (c) 2012, Google Inc. All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions are |
| * met: |
| * |
| * * Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * * Redistributions in binary form must reproduce the above |
| * copyright notice, this list of conditions and the following disclaimer |
| * in the documentation and/or other materials provided with the |
| * distribution. |
| * * Neither the name of Google Inc. nor the names of its |
| * contributors may be used to endorse or promote products derived from |
| * this software without specific prior written permission. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR |
| * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT |
| * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
| * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| */ |
| |
| #ifndef WritingMode_h |
| #define WritingMode_h |
| |
| namespace blink { |
| |
| // These values are named to match the CSS keywords they correspond to: namely |
| // horizontal-tb, vertical-rl and vertical-lr. |
| // Since these names aren't very self-explanatory, where possible use the |
| // inline utility functions below. |
| enum class WritingMode : unsigned { |
| kHorizontalTb = 0, |
| kVerticalRl = 1, |
| kVerticalLr = 2, |
| // sideways-rl and sideways-lr are only supported by LayoutNG. |
| kSidewaysRl = 3, |
| kSidewaysLr = 4 |
| }; |
| |
| // Lines have horizontal orientation; modes horizontal-tb. |
| inline bool IsHorizontalWritingMode(WritingMode writing_mode) { |
| return writing_mode == WritingMode::kHorizontalTb; |
| } |
| |
| // Bottom of the line occurs earlier in the block; modes vertical-lr. |
| inline bool IsFlippedLinesWritingMode(WritingMode writing_mode) { |
| return writing_mode == WritingMode::kVerticalLr; |
| } |
| |
| // Block progression increases in the opposite direction to normal; modes |
| // vertical-rl. |
| inline bool IsFlippedBlocksWritingMode(WritingMode writing_mode) { |
| return writing_mode == WritingMode::kVerticalRl; |
| } |
| |
| // Whether the child and the containing block are parallel to each other. |
| // Example: vertical-rl and vertical-lr |
| inline bool IsParallelWritingMode(WritingMode a, WritingMode b) { |
| return (a == WritingMode::kHorizontalTb) == (b == WritingMode::kHorizontalTb); |
| } |
| |
| } // namespace blink |
| |
| #endif // WritingMode_h |
