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authorTom Sepez <tsepez@chromium.org>2016-02-12 10:29:21 -0800
committerTom Sepez <tsepez@chromium.org>2016-02-12 10:29:21 -0800
commit5a5f1f1c905f2c352d2fbde143456124dd2c0fbf (patch)
tree60e59c107a9edbc314636c1ca05094bae4f32204 /core/include/fxcrt/fx_bidi.h
parent6b90e983a9e3e7aee0c637a7b0c3c51f0dfc1faf (diff)
downloadpdfium-5a5f1f1c905f2c352d2fbde143456124dd2c0fbf.tar.xz
Make fx_bidi sane.
Replace array of heterogenous ints with array of struct. Create a class for traversing a string. Flip array when R2L and process with forward iterator always. R=thestig@chromium.org Review URL: https://codereview.chromium.org/1682983002 .
Diffstat (limited to 'core/include/fxcrt/fx_bidi.h')
-rw-r--r--core/include/fxcrt/fx_bidi.h54
1 files changed, 34 insertions, 20 deletions
diff --git a/core/include/fxcrt/fx_bidi.h b/core/include/fxcrt/fx_bidi.h
index a55ce6cfd2..ecf888b306 100644
--- a/core/include/fxcrt/fx_bidi.h
+++ b/core/include/fxcrt/fx_bidi.h
@@ -7,15 +7,23 @@
#ifndef CORE_INCLUDE_FXCRT_FX_BIDI_H_
#define CORE_INCLUDE_FXCRT_FX_BIDI_H_
+#include <memory>
+#include <vector>
+
+#include "fx_string.h"
#include "fx_system.h"
// Processes characters and group them into segments based on text direction.
class CFX_BidiChar {
public:
enum Direction { NEUTRAL, LEFT, RIGHT };
+ struct Segment {
+ int32_t start; // Start position.
+ int32_t count; // Character count.
+ Direction direction; // Segment direction.
+ };
CFX_BidiChar();
- ~CFX_BidiChar();
// Append a character and classify it as left, right, or neutral.
// Returns true if the character has a different direction than the
@@ -27,33 +35,39 @@ class CFX_BidiChar {
// Returns true if there is still a segment to process.
bool EndChar();
- // Get information about the segment to process.
- // The segment's start position and character count is returned in |iStart|
- // and |iCount|, respectively. Pass in null pointers if the information is
- // not needed.
- // Returns the segment direction.
- Direction GetBidiInfo(int32_t* iStart, int32_t* iCount) const;
+ // Call after a change in direction is indicated by the above to get
+ // information about the segment to process.
+ Segment GetSegmentInfo() const { return m_LastSegment; }
private:
- void SaveCurrentStateToLastState();
+ void StartNewSegment(CFX_BidiChar::Direction direction);
- // Position of the current segment.
- int32_t m_iCurStart;
+ Segment m_CurrentSegment;
+ Segment m_LastSegment;
+};
- // Number of characters in the current segment.
- int32_t m_iCurCount;
+class CFX_BidiString {
+ public:
+ using const_iterator = std::vector<CFX_BidiChar::Segment>::const_iterator;
+ explicit CFX_BidiString(const CFX_WideString& str);
- // Direction of the current segment.
- Direction m_CurBidi;
+ // Overall direction is always LEFT or RIGHT, never NEUTRAL.
+ CFX_BidiChar::Direction OverallDirection() const {
+ return m_eOverallDirection;
+ }
- // Number of characters in the last segment.
- int32_t m_iLastStart;
+ // Force the overall direction to be R2L regardless of what was detected.
+ void SetOverallDirectionRight();
- // Number of characters in the last segment.
- int32_t m_iLastCount;
+ FX_WCHAR CharAt(size_t x) const { return m_Str[x]; }
+ const_iterator begin() const { return m_Order.begin(); }
+ const_iterator end() const { return m_Order.end(); }
- // Direction of the last segment.
- Direction m_LastBidi;
+ private:
+ const CFX_WideString m_Str;
+ std::unique_ptr<CFX_BidiChar> m_pBidiChar;
+ std::vector<CFX_BidiChar::Segment> m_Order;
+ CFX_BidiChar::Direction m_eOverallDirection;
};
#endif // CORE_INCLUDE_FXCRT_FX_BIDI_H_