ui/gfx/render_text_win.h

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef UI_GFX_RENDER_TEXT_WIN_H_
   6 #define UI_GFX_RENDER_TEXT_WIN_H_
   7
   8 #include <usp10.h>
   9
  10 #include <map>
  11 #include <string>
  12 #include <vector>
  13
  14 #include "base/memory/scoped_ptr.h"
  15 #include "base/memory/scoped_vector.h"
  16 #include "ui/gfx/render_text.h"
  17
  18 namespace gfx {
  19
  20 namespace internal {
  21
  22 struct TextRun {
  23   TextRun();
  24   ~TextRun();
  25
  26   Range range;
  27   Font font;
  28   // A gfx::Font::FontStyle flag to specify bold and italic styles.
  29   // Supersedes |font.GetFontStyle()|. Stored separately to avoid calling
  30   // |font.DeriveFont()|, which is expensive on Windows.
  31   int font_style;
  32
  33   bool strike;
  34   bool diagonal_strike;
  35   bool underline;
  36
  37   int width;
  38   // The cumulative widths of preceding runs.
  39   int preceding_run_widths;
  40
  41   SCRIPT_ANALYSIS script_analysis;
  42
  43   scoped_ptr<WORD[]> glyphs;
  44   scoped_ptr<WORD[]> logical_clusters;
  45   scoped_ptr<SCRIPT_VISATTR[]> visible_attributes;
  46   int glyph_count;
  47
  48   scoped_ptr<int[]> advance_widths;
  49   scoped_ptr<GOFFSET[]> offsets;
  50   ABC abc_widths;
  51   SCRIPT_CACHE script_cache;
  52
  53  private:
  54   DISALLOW_COPY_AND_ASSIGN(TextRun);
  55 };
  56
  57 }  // namespace internal
  58
  59 // RenderTextWin is the Windows implementation of RenderText using Uniscribe.
  60 class RenderTextWin : public RenderText {
  61  public:
  62   RenderTextWin();
  63   virtual ~RenderTextWin();
  64
  65   // Overridden from RenderText:
  66   virtual Size GetStringSize() OVERRIDE;
  67   virtual SelectionModel FindCursorPosition(const Point& point) OVERRIDE;
  68   virtual std::vector<FontSpan> GetFontSpansForTesting() OVERRIDE;
  69
  70  protected:
  71   // Overridden from RenderText:
  72   virtual int GetLayoutTextBaseline() OVERRIDE;
  73   virtual SelectionModel AdjacentCharSelectionModel(
  74       const SelectionModel& selection,
  75       VisualCursorDirection direction) OVERRIDE;
  76   virtual SelectionModel AdjacentWordSelectionModel(
  77       const SelectionModel& selection,
  78       VisualCursorDirection direction) OVERRIDE;
  79   virtual Range GetGlyphBounds(size_t index) OVERRIDE;
  80   virtual std::vector<Rect> GetSubstringBounds(const Range& range) OVERRIDE;
  81   virtual size_t TextIndexToLayoutIndex(size_t index) const OVERRIDE;
  82   virtual size_t LayoutIndexToTextIndex(size_t index) const OVERRIDE;
  83   virtual bool IsValidCursorIndex(size_t index) OVERRIDE;
  84   virtual void ResetLayout() OVERRIDE;
  85   virtual void EnsureLayout() OVERRIDE;
  86   virtual void DrawVisualText(Canvas* canvas) OVERRIDE;
  87
  88  private:
  89   FRIEND_TEST_ALL_PREFIXES(RenderTextTest, Win_BreakRunsByUnicodeBlocks);
  90   FRIEND_TEST_ALL_PREFIXES(RenderTextTest, Win_LogicalClusters);
  91   FRIEND_TEST_ALL_PREFIXES(RenderTextTest, Multiline_MinWidth);
  92   FRIEND_TEST_ALL_PREFIXES(RenderTextTest, Multiline_NormalWidth);
  93   FRIEND_TEST_ALL_PREFIXES(RenderTextTest, BreakRunsByUnicodeBlocks);
  94
  95   void ItemizeLogicalText();
  96   void LayoutVisualText();
  97   void LayoutTextRun(internal::TextRun* run);
  98
  99   // Helper function that calls |ScriptShape()| on the run, which has logic to
 100   // handle E_OUTOFMEMORY return codes.
 101   HRESULT ShapeTextRunWithFont(internal::TextRun* run, const Font& font);
 102
 103   // Returns the number of characters in |run| that have missing glyphs.
 104   int CountCharsWithMissingGlyphs(internal::TextRun* run,
 105                                   HRESULT shaping_result) const;
 106
 107   // Return the run index that contains the argument; or the length of the
 108   // |runs_| vector if argument exceeds the text length or width.
 109   size_t GetRunContainingCaret(const SelectionModel& caret) const;
 110   size_t GetRunContainingXCoord(int x) const;
 111
 112   // Given a |run|, returns the SelectionModel that contains the logical first
 113   // or last caret position inside (not at a boundary of) the run.
 114   // The returned value represents a cursor/caret position without a selection.
 115   SelectionModel FirstSelectionModelInsideRun(const internal::TextRun* run);
 116   SelectionModel LastSelectionModelInsideRun(const internal::TextRun* run);
 117
 118   // Cached HDC for performing Uniscribe API calls.
 119   static HDC cached_hdc_;
 120
 121   // Cached map from font name to the last successful substitute font used.
 122   // TODO(asvitkine): Move the caching logic to font_fallback_win.cc.
 123   static std::map<std::string, Font> successful_substitute_fonts_;
 124
 125   SCRIPT_CONTROL script_control_;
 126   SCRIPT_STATE script_state_;
 127
 128   ScopedVector<internal::TextRun> runs_;
 129
 130   // Single line width of the layout text.
 131   int string_width_;
 132
 133   // Wrapped multiline size of the layout text.
 134   Size multiline_string_size_;
 135
 136   scoped_ptr<int[]> visual_to_logical_;
 137   scoped_ptr<int[]> logical_to_visual_;
 138
 139   bool needs_layout_;
 140
 141   DISALLOW_COPY_AND_ASSIGN(RenderTextWin);
 142 };
 143
 144 }  // namespace gfx
 145
 146 #endif  // UI_GFX_RENDER_TEXT_WIN_H_