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
13namespace gfx {
14
15// RenderTextPango is the Linux implementation of RenderText using Pango.
16class 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_
89