ui/gfx/render_text_pango.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_PANGO_H_
   6 #define UI_GFX_RENDER_TEXT_PANGO_H_
   7
   8 #include <pango/pango.h>
   9 #include <vector>
  10
  11 #include "ui/gfx/render_text.h"
  12
  13 namespace gfx {
  14
  15 // RenderTextPango is the Linux implementation of RenderText using Pango.
  16 class RenderTextPango : public RenderText {
  17  public:
  18   RenderTextPango();
  19   virtual ~RenderTextPango();
  20
  21   // Overridden from RenderText:
  22   virtual Size GetStringSize() OVERRIDE;
  23   virtual SelectionModel FindCursorPosition(const Point& point) OVERRIDE;
  24   virtual std::vector<FontSpan> GetFontSpansForTesting() OVERRIDE;
  25
  26  protected:
  27   // Overridden from RenderText:
  28   virtual int GetLayoutTextBaseline() OVERRIDE;
  29   virtual SelectionModel AdjacentCharSelectionModel(
  30       const SelectionModel& selection,
  31       VisualCursorDirection direction) OVERRIDE;
  32   virtual SelectionModel AdjacentWordSelectionModel(
  33       const SelectionModel& selection,
  34       VisualCursorDirection direction) OVERRIDE;
  35   virtual Range GetGlyphBounds(size_t index) OVERRIDE;
  36   virtual std::vector<Rect> GetSubstringBounds(const Range& range) OVERRIDE;
  37   virtual size_t TextIndexToLayoutIndex(size_t index) const OVERRIDE;
  38   virtual size_t LayoutIndexToTextIndex(size_t index) const OVERRIDE;
  39   virtual bool IsValidCursorIndex(size_t index) OVERRIDE;
  40   virtual void ResetLayout() OVERRIDE;
  41   virtual void EnsureLayout() OVERRIDE;
  42   virtual void DrawVisualText(Canvas* canvas) OVERRIDE;
  43
  44  private:
  45   friend class RenderTextTest;
  46   FRIEND_TEST_ALL_PREFIXES(RenderTextTest, PangoAttributes);
  47
  48   // Returns the run that contains the character attached to the caret in the
  49   // given selection model. Return NULL if not found.
  50   GSList* GetRunContainingCaret(const SelectionModel& caret) const;
  51
  52   // Given a |run|, returns the SelectionModel that contains the logical first
  53   // or last caret position inside (not at a boundary of) the run.
  54   // The returned value represents a cursor/caret position without a selection.
  55   SelectionModel FirstSelectionModelInsideRun(const PangoItem* run);
  56   SelectionModel LastSelectionModelInsideRun(const PangoItem* run);
  57
  58   // Setup pango attribute: foreground, background, font, strike.
  59   void SetupPangoAttributes(PangoLayout* layout);
  60
  61   // Append one pango attribute |pango_attr| into pango attribute list |attrs|.
  62   void AppendPangoAttribute(size_t start,
  63                             size_t end,
  64                             PangoAttribute* pango_attr,
  65                             PangoAttrList* attrs);
  66
  67   // Get the text index corresponding to the |run|'s |glyph_index|.
  68   size_t GetGlyphTextIndex(PangoLayoutRun* run, int glyph_index) const;
  69
  70   // Pango Layout.
  71   PangoLayout* layout_;
  72   // A single line layout resulting from laying out via |layout_|.
  73   PangoLayoutLine* current_line_;
  74
  75   // Information about character attributes.
  76   PangoLogAttr* log_attrs_;
  77   // Number of attributes in |log_attrs_|.
  78   int num_log_attrs_;
  79
  80   // The text in the |layout_|.
  81   const char* layout_text_;
  82
  83   DISALLOW_COPY_AND_ASSIGN(RenderTextPango);
  84 };
  85
  86 }  // namespace gfx
  87
  88 #endif  // UI_GFX_RENDER_TEXT_PANGO_H_