1 /*
2 * Copyright (c) 2012, Google Inc. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions are
6 * met:
7 *
8 * * Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * * Redistributions in binary form must reproduce the above
11 * copyright notice, this list of conditions and the following disclaimer
12 * in the documentation and/or other materials provided with the
13 * distribution.
14 * * Neither the name of Google Inc. nor the names of its
15 * contributors may be used to endorse or promote products derived from
16 * this software without specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
21 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
22 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
23 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
24 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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28 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29 */
30
31 #ifndef WritingMode_h
32 #define WritingMode_h
33
34 namespace blink {
35
36 enum WritingMode {
37 TopToBottomWritingMode, RightToLeftWritingMode, LeftToRightWritingMode, BottomToTopWritingMode
38 };
39
40 // Lines have horizontal orientation; modes horizontal-tb or horizontal-bt.
isHorizontalWritingMode(WritingMode writingMode)41 inline bool isHorizontalWritingMode(WritingMode writingMode)
42 {
43 return writingMode == TopToBottomWritingMode || writingMode == BottomToTopWritingMode;
44 }
45
46 // Bottom of the line occurs earlier in the block; modes vertical-lr or horizontal-bt.
isFlippedLinesWritingMode(WritingMode writingMode)47 inline bool isFlippedLinesWritingMode(WritingMode writingMode)
48 {
49 return writingMode == LeftToRightWritingMode || writingMode == BottomToTopWritingMode;
50 }
51
52 // Block progression increases in the opposite direction to normal; modes vertical-rl or horizontal-bt.
isFlippedBlocksWritingMode(WritingMode writingMode)53 inline bool isFlippedBlocksWritingMode(WritingMode writingMode)
54 {
55 return writingMode == RightToLeftWritingMode || writingMode == BottomToTopWritingMode;
56 }
57
58 } // namespace blink
59
60 #endif // WritingMode_h
61