ui/gfx/render

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This source file includes following definitions.
DetermineBaselineCenteringText
ConvertFontStyleToSkiaTypefaceStyle
CalculateFadeGradientWidth
AddFadeEffect
CreateFadeShader
underline_position_
SetDrawLooper
SetFontSmoothingSettings
SetFontHinting
SetTypeface
SetTextSize
SetFontFamilyWithStyle
SetForegroundColor
SetShader
SetUnderlineMetrics
DrawPosText
DrawDecorations
EndDiagonalStrike
DrawUnderline
DrawStrike
total_length_
AddPiece
Draw
styles_
GetRange
UpdatePosition
baseline
SetText
SetHorizontalAlignment
SetFontList
SetCursorEnabled
ToggleInsertMode
SetObscured
SetObscuredRevealIndex
SetMultiline
SetElideBehavior
SetDisplayRect
SetCursorPosition
MoveCursor
MoveCursorTo
MoveCursorTo
SelectRange
IsPointInSelection
ClearSelection
SelectAll
SelectWord
GetCompositionRange
SetCompositionRange
SetColor
ApplyColor
SetStyle
ApplyStyle
GetStyle
SetDirectionalityMode
GetTextDirection
GetVisualDirectionOfLogicalEnd
GetStringSizeF
GetContentWidth
GetBaseline
Draw
DrawCursor
GetCursorBounds
GetUpdatedCursorBounds
IndexOfAdjacentGrapheme
GetSelectionModelForSelectionStart
SetTextShadows
cached_bounds_and_offset_valid_
GetUpdatedDisplayOffset
GetAdjacentSelectionModel
EdgeSelectionModel
SetSelectionModel
GetLayoutText
GetLineBreaks
ApplyCompositionAndSelectionStyles
UndoCompositionAndSelectionStyles
GetLineOffset
ToTextPoint
ToViewPoint
TextBoundsToViewBounds
GetAlignmentOffset
ApplyFadeEffects
ApplyTextShadows
RangeContainsCaret
MoveCursorTo
UpdateLayoutText
ElideText
UpdateCachedBoundsAndOffset
DrawSelection
// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "ui/gfx/render_text.h"

#include <algorithm>
#include <climits>

#include "base/i18n/break_iterator.h"
#include "base/logging.h"
#include "base/stl_util.h"
#include "base/strings/utf_string_conversions.h"
#include "third_party/icu/source/common/unicode/rbbi.h"
#include "third_party/icu/source/common/unicode/utf16.h"
#include "third_party/skia/include/core/SkTypeface.h"
#include "third_party/skia/include/effects/SkGradientShader.h"
#include "ui/gfx/canvas.h"
#include "ui/gfx/insets.h"
#include "ui/gfx/skia_util.h"
#include "ui/gfx/text_constants.h"
#include "ui/gfx/text_elider.h"
#include "ui/gfx/text_utils.h"
#include "ui/gfx/utf16_indexing.h"

namespace gfx {

namespace {

// All chars are replaced by this char when the password style is set.
// TODO(benrg): GTK uses the first of U+25CF, U+2022, U+2731, U+273A, '*'
// that's available in the font (find_invisible_char() in gtkentry.c).
const base::char16 kPasswordReplacementChar = '*';

// Default color used for the text and cursor.
const SkColor kDefaultColor = SK_ColorBLACK;

// Default color used for drawing selection background.
const SkColor kDefaultSelectionBackgroundColor = SK_ColorGRAY;

// Fraction of the text size to lower a strike through below the baseline.
const SkScalar kStrikeThroughOffset = (-SK_Scalar1 * 6 / 21);
// Fraction of the text size to lower an underline below the baseline.
const SkScalar kUnderlineOffset = (SK_Scalar1 / 9);
// Fraction of the text size to use for a strike through or under-line.
const SkScalar kLineThickness = (SK_Scalar1 / 18);
// Fraction of the text size to use for a top margin of a diagonal strike.
const SkScalar kDiagonalStrikeMarginOffset = (SK_Scalar1 / 4);

// Invalid value of baseline.  Assigning this value to |baseline_| causes
// re-calculation of baseline.
const int kInvalidBaseline = INT_MAX;

// Returns the baseline, with which the text best appears vertically centered.
int DetermineBaselineCenteringText(const Rect& display_rect,
                                   const FontList& font_list) {
  const int display_height = display_rect.height();
  const int font_height = font_list.GetHeight();
  // Lower and upper bound of baseline shift as we try to show as much area of
  // text as possible.  In particular case of |display_height| == |font_height|,
  // we do not want to shift the baseline.
  const int min_shift = std::min(0, display_height - font_height);
  const int max_shift = std::abs(display_height - font_height);
  const int baseline = font_list.GetBaseline();
  const int cap_height = font_list.GetCapHeight();
  const int internal_leading = baseline - cap_height;
  // Some platforms don't support getting the cap height, and simply return
  // the entire font ascent from GetCapHeight().  Centering the ascent makes
  // the font look too low, so if GetCapHeight() returns the ascent, center
  // the entire font height instead.
  const int space =
      display_height - ((internal_leading != 0) ? cap_height : font_height);
  const int baseline_shift = space / 2 - internal_leading;
  return baseline + std::max(min_shift, std::min(max_shift, baseline_shift));
}

// Converts |gfx::Font::FontStyle| flags to |SkTypeface::Style| flags.
SkTypeface::Style ConvertFontStyleToSkiaTypefaceStyle(int font_style) {
  int skia_style = SkTypeface::kNormal;
  skia_style |= (font_style & gfx::Font::BOLD) ? SkTypeface::kBold : 0;
  skia_style |= (font_style & gfx::Font::ITALIC) ? SkTypeface::kItalic : 0;
  return static_cast<SkTypeface::Style>(skia_style);
}

// Given |font| and |display_width|, returns the width of the fade gradient.
int CalculateFadeGradientWidth(const FontList& font_list, int display_width) {
  // Fade in/out about 2.5 characters of the beginning/end of the string.
  // The .5 here is helpful if one of the characters is a space.
  // Use a quarter of the display width if the display width is very short.
  const int average_character_width = font_list.GetExpectedTextWidth(1);
  const double gradient_width = std::min(average_character_width * 2.5,
                                         display_width / 4.0);
  DCHECK_GE(gradient_width, 0.0);
  return static_cast<int>(floor(gradient_width + 0.5));
}

// Appends to |positions| and |colors| values corresponding to the fade over
// |fade_rect| from color |c0| to color |c1|.
void AddFadeEffect(const Rect& text_rect,
                   const Rect& fade_rect,
                   SkColor c0,
                   SkColor c1,
                   std::vector<SkScalar>* positions,
                   std::vector<SkColor>* colors) {
  const SkScalar left = static_cast<SkScalar>(fade_rect.x() - text_rect.x());
  const SkScalar width = static_cast<SkScalar>(fade_rect.width());
  const SkScalar p0 = left / text_rect.width();
  const SkScalar p1 = (left + width) / text_rect.width();
  // Prepend 0.0 to |positions|, as required by Skia.
  if (positions->empty() && p0 != 0.0) {
    positions->push_back(0.0);
    colors->push_back(c0);
  }
  positions->push_back(p0);
  colors->push_back(c0);
  positions->push_back(p1);
  colors->push_back(c1);
}

// Creates a SkShader to fade the text, with |left_part| specifying the left
// fade effect, if any, and |right_part| specifying the right fade effect.
skia::RefPtr<SkShader> CreateFadeShader(const Rect& text_rect,
                                        const Rect& left_part,
                                        const Rect& right_part,
                                        SkColor color) {
  // Fade alpha of 51/255 corresponds to a fade of 0.2 of the original color.
  const SkColor fade_color = SkColorSetA(color, 51);
  std::vector<SkScalar> positions;
  std::vector<SkColor> colors;

  if (!left_part.IsEmpty())
    AddFadeEffect(text_rect, left_part, fade_color, color,
                  &positions, &colors);
  if (!right_part.IsEmpty())
    AddFadeEffect(text_rect, right_part, color, fade_color,
                  &positions, &colors);
  DCHECK(!positions.empty());

  // Terminate |positions| with 1.0, as required by Skia.
  if (positions.back() != 1.0) {
    positions.push_back(1.0);
    colors.push_back(colors.back());
  }

  SkPoint points[2];
  points[0].iset(text_rect.x(), text_rect.y());
  points[1].iset(text_rect.right(), text_rect.y());

  return skia::AdoptRef(
      SkGradientShader::CreateLinear(&points[0], &colors[0], &positions[0],
                                     colors.size(), SkShader::kClamp_TileMode));
}

}  // namespace

namespace internal {

// Value of |underline_thickness_| that indicates that underline metrics have
// not been set explicitly.
const SkScalar kUnderlineMetricsNotSet = -1.0f;

SkiaTextRenderer::SkiaTextRenderer(Canvas* canvas)
    : canvas_(canvas),
      canvas_skia_(canvas->sk_canvas()),
      started_drawing_(false),
      underline_thickness_(kUnderlineMetricsNotSet),
      underline_position_(0.0f) {
  DCHECK(canvas_skia_);
  paint_.setTextEncoding(SkPaint::kGlyphID_TextEncoding);
  paint_.setStyle(SkPaint::kFill_Style);
  paint_.setAntiAlias(true);
  paint_.setSubpixelText(true);
  paint_.setLCDRenderText(true);
  paint_.setHinting(SkPaint::kNormal_Hinting);
  bounds_.setEmpty();
}

SkiaTextRenderer::~SkiaTextRenderer() {
  // Work-around for http://crbug.com/122743, where non-ClearType text is
  // rendered with incorrect gamma when using the fade shader. Draw the text
  // to a layer and restore it faded by drawing a rect in kDstIn_Mode mode.
  //
  // TODO(asvitkine): Remove this work-around once the Skia bug is fixed.
  //                  http://code.google.com/p/skia/issues/detail?id=590
  if (deferred_fade_shader_.get()) {
    paint_.setShader(deferred_fade_shader_.get());
    paint_.setXfermodeMode(SkXfermode::kDstIn_Mode);
    canvas_skia_->drawRect(bounds_, paint_);
    canvas_skia_->restore();
  }
}

void SkiaTextRenderer::SetDrawLooper(SkDrawLooper* draw_looper) {
  paint_.setLooper(draw_looper);
}

void SkiaTextRenderer::SetFontSmoothingSettings(bool antialiasing,
                                                bool subpixel_rendering,
                                                bool subpixel_positioning) {
  paint_.setAntiAlias(antialiasing);
  paint_.setLCDRenderText(subpixel_rendering);
  paint_.setSubpixelText(subpixel_positioning);
}

void SkiaTextRenderer::SetFontHinting(SkPaint::Hinting hinting) {
  paint_.setHinting(hinting);
}

void SkiaTextRenderer::SetTypeface(SkTypeface* typeface) {
  paint_.setTypeface(typeface);
}

void SkiaTextRenderer::SetTextSize(SkScalar size) {
  paint_.setTextSize(size);
}

void SkiaTextRenderer::SetFontFamilyWithStyle(const std::string& family,
                                              int style) {
  DCHECK(!family.empty());

  SkTypeface::Style skia_style = ConvertFontStyleToSkiaTypefaceStyle(style);
  skia::RefPtr<SkTypeface> typeface =
      skia::AdoptRef(SkTypeface::CreateFromName(family.c_str(), skia_style));
  if (typeface) {
    // |paint_| adds its own ref. So don't |release()| it from the ref ptr here.
    SetTypeface(typeface.get());

    // Enable fake bold text if bold style is needed but new typeface does not
    // have it.
    paint_.setFakeBoldText((skia_style & SkTypeface::kBold) &&
                           !typeface->isBold());
  }
}

void SkiaTextRenderer::SetForegroundColor(SkColor foreground) {
  paint_.setColor(foreground);
}

void SkiaTextRenderer::SetShader(SkShader* shader, const Rect& bounds) {
  bounds_ = RectToSkRect(bounds);
  paint_.setShader(shader);
}

void SkiaTextRenderer::SetUnderlineMetrics(SkScalar thickness,
                                           SkScalar position) {
  underline_thickness_ = thickness;
  underline_position_ = position;
}

void SkiaTextRenderer::DrawPosText(const SkPoint* pos,
                                   const uint16* glyphs,
                                   size_t glyph_count) {
  if (!started_drawing_) {
    started_drawing_ = true;
    // Work-around for http://crbug.com/122743, where non-ClearType text is
    // rendered with incorrect gamma when using the fade shader. Draw the text
    // to a layer and restore it faded by drawing a rect in kDstIn_Mode mode.
    //
    // Skip this when there is a looper which seems not working well with
    // deferred paint. Currently a looper is only used for text shadows.
    //
    // TODO(asvitkine): Remove this work-around once the Skia bug is fixed.
    //                  http://code.google.com/p/skia/issues/detail?id=590
    if (!paint_.isLCDRenderText() &&
        paint_.getShader() &&
        !paint_.getLooper()) {
      deferred_fade_shader_ = skia::SharePtr(paint_.getShader());
      paint_.setShader(NULL);
      canvas_skia_->saveLayer(&bounds_, NULL);
    }
  }

  const size_t byte_length = glyph_count * sizeof(glyphs[0]);
  canvas_skia_->drawPosText(&glyphs[0], byte_length, &pos[0], paint_);
}

void SkiaTextRenderer::DrawDecorations(int x, int y, int width, bool underline,
                                       bool strike, bool diagonal_strike) {
  if (underline)
    DrawUnderline(x, y, width);
  if (strike)
    DrawStrike(x, y, width);
  if (diagonal_strike) {
    if (!diagonal_)
      diagonal_.reset(new DiagonalStrike(canvas_, Point(x, y), paint_));
    diagonal_->AddPiece(width, paint_.getColor());
  } else if (diagonal_) {
    EndDiagonalStrike();
  }
}

void SkiaTextRenderer::EndDiagonalStrike() {
  if (diagonal_) {
    diagonal_->Draw();
    diagonal_.reset();
  }
}

void SkiaTextRenderer::DrawUnderline(int x, int y, int width) {
  SkRect r = SkRect::MakeLTRB(x, y + underline_position_, x + width,
                              y + underline_position_ + underline_thickness_);
  if (underline_thickness_ == kUnderlineMetricsNotSet) {
    const SkScalar text_size = paint_.getTextSize();
    r.fTop = SkScalarMulAdd(text_size, kUnderlineOffset, y);
    r.fBottom = r.fTop + SkScalarMul(text_size, kLineThickness);
  }
  canvas_skia_->drawRect(r, paint_);
}

void SkiaTextRenderer::DrawStrike(int x, int y, int width) const {
  const SkScalar text_size = paint_.getTextSize();
  const SkScalar height = SkScalarMul(text_size, kLineThickness);
  const SkScalar offset = SkScalarMulAdd(text_size, kStrikeThroughOffset, y);
  const SkRect r = SkRect::MakeLTRB(x, offset, x + width, offset + height);
  canvas_skia_->drawRect(r, paint_);
}

SkiaTextRenderer::DiagonalStrike::DiagonalStrike(Canvas* canvas,
                                                 Point start,
                                                 const SkPaint& paint)
    : canvas_(canvas),
      start_(start),
      paint_(paint),
      total_length_(0) {
}

SkiaTextRenderer::DiagonalStrike::~DiagonalStrike() {
}

void SkiaTextRenderer::DiagonalStrike::AddPiece(int length, SkColor color) {
  pieces_.push_back(Piece(length, color));
  total_length_ += length;
}

void SkiaTextRenderer::DiagonalStrike::Draw() {
  const SkScalar text_size = paint_.getTextSize();
  const SkScalar offset = SkScalarMul(text_size, kDiagonalStrikeMarginOffset);
  const int thickness =
      SkScalarCeilToInt(SkScalarMul(text_size, kLineThickness) * 2);
  const int height = SkScalarCeilToInt(text_size - offset);
  const Point end = start_ + Vector2d(total_length_, -height);

  paint_.setAntiAlias(true);
  paint_.setStrokeWidth(thickness);

  const bool clipped = pieces_.size() > 1;
  int x = start_.x();
  for (size_t i = 0; i < pieces_.size(); ++i) {
    paint_.setColor(pieces_[i].second);

    if (clipped) {
      canvas_->Save();
      canvas_->ClipRect(Rect(x, 0, pieces_[i].first, start_.y() + thickness));
    }

    canvas_->DrawLine(start_, end, paint_);

    if (clipped)
      canvas_->Restore();

    x += pieces_[i].first;
  }
}

StyleIterator::StyleIterator(const BreakList<SkColor>& colors,
                             const std::vector<BreakList<bool> >& styles)
    : colors_(colors),
      styles_(styles) {
  color_ = colors_.breaks().begin();
  for (size_t i = 0; i < styles_.size(); ++i)
    style_.push_back(styles_[i].breaks().begin());
}

StyleIterator::~StyleIterator() {}

Range StyleIterator::GetRange() const {
  Range range(colors_.GetRange(color_));
  for (size_t i = 0; i < NUM_TEXT_STYLES; ++i)
    range = range.Intersect(styles_[i].GetRange(style_[i]));
  return range;
}

void StyleIterator::UpdatePosition(size_t position) {
  color_ = colors_.GetBreak(position);
  for (size_t i = 0; i < NUM_TEXT_STYLES; ++i)
    style_[i] = styles_[i].GetBreak(position);
}

LineSegment::LineSegment() : run(0) {}

LineSegment::~LineSegment() {}

Line::Line() : preceding_heights(0), baseline(0) {}

Line::~Line() {}

}  // namespace internal

RenderText::~RenderText() {
}

void RenderText::SetText(const base::string16& text) {
  DCHECK(!composition_range_.IsValid());
  if (text_ == text)
    return;
  text_ = text;

  // Adjust ranged styles and colors to accommodate a new text length.
  const size_t text_length = text_.length();
  colors_.SetMax(text_length);
  for (size_t style = 0; style < NUM_TEXT_STYLES; ++style)
    styles_[style].SetMax(text_length);
  cached_bounds_and_offset_valid_ = false;

  // Reset selection model. SetText should always followed by SetSelectionModel
  // or SetCursorPosition in upper layer.
  SetSelectionModel(SelectionModel());

  // Invalidate the cached text direction if it depends on the text contents.
  if (directionality_mode_ == DIRECTIONALITY_FROM_TEXT)
    text_direction_ = base::i18n::UNKNOWN_DIRECTION;

  obscured_reveal_index_ = -1;
  UpdateLayoutText();
}

void RenderText::SetHorizontalAlignment(HorizontalAlignment alignment) {
  if (horizontal_alignment_ != alignment) {
    horizontal_alignment_ = alignment;
    display_offset_ = Vector2d();
    cached_bounds_and_offset_valid_ = false;
  }
}

void RenderText::SetFontList(const FontList& font_list) {
  font_list_ = font_list;
  baseline_ = kInvalidBaseline;
  cached_bounds_and_offset_valid_ = false;
  ResetLayout();
}

void RenderText::SetCursorEnabled(bool cursor_enabled) {
  cursor_enabled_ = cursor_enabled;
  cached_bounds_and_offset_valid_ = false;
}

void RenderText::ToggleInsertMode() {
  insert_mode_ = !insert_mode_;
  cached_bounds_and_offset_valid_ = false;
}

void RenderText::SetObscured(bool obscured) {
  if (obscured != obscured_) {
    obscured_ = obscured;
    obscured_reveal_index_ = -1;
    cached_bounds_and_offset_valid_ = false;
    UpdateLayoutText();
  }
}

void RenderText::SetObscuredRevealIndex(int index) {
  if (obscured_reveal_index_ == index)
    return;

  obscured_reveal_index_ = index;
  cached_bounds_and_offset_valid_ = false;
  UpdateLayoutText();
}

void RenderText::SetMultiline(bool multiline) {
  if (multiline != multiline_) {
    multiline_ = multiline;
    cached_bounds_and_offset_valid_ = false;
    lines_.clear();
  }
}

void RenderText::SetElideBehavior(ElideBehavior elide_behavior) {
  // TODO(skanuj) : Add a test for triggering layout change.
  if (elide_behavior_ != elide_behavior) {
    elide_behavior_ = elide_behavior;
    UpdateLayoutText();
  }
}

void RenderText::SetDisplayRect(const Rect& r) {
  if (r != display_rect_) {
    display_rect_ = r;
    baseline_ = kInvalidBaseline;
    cached_bounds_and_offset_valid_ = false;
    lines_.clear();
    if (elide_behavior_ != gfx::NO_ELIDE)
      UpdateLayoutText();
  }
}

void RenderText::SetCursorPosition(size_t position) {
  MoveCursorTo(position, false);
}

void RenderText::MoveCursor(BreakType break_type,
                            VisualCursorDirection direction,
                            bool select) {
  SelectionModel position(cursor_position(), selection_model_.caret_affinity());
  // Cancelling a selection moves to the edge of the selection.
  if (break_type != LINE_BREAK && !selection().is_empty() && !select) {
    SelectionModel selection_start = GetSelectionModelForSelectionStart();
    int start_x = GetCursorBounds(selection_start, true).x();
    int cursor_x = GetCursorBounds(position, true).x();
    // Use the selection start if it is left (when |direction| is CURSOR_LEFT)
    // or right (when |direction| is CURSOR_RIGHT) of the selection end.
    if (direction == CURSOR_RIGHT ? start_x > cursor_x : start_x < cursor_x)
      position = selection_start;
    // For word breaks, use the nearest word boundary in the appropriate
    // |direction|.
    if (break_type == WORD_BREAK)
      position = GetAdjacentSelectionModel(position, break_type, direction);
  } else {
    position = GetAdjacentSelectionModel(position, break_type, direction);
  }
  if (select)
    position.set_selection_start(selection().start());
  MoveCursorTo(position);
}

bool RenderText::MoveCursorTo(const SelectionModel& model) {
  // Enforce valid selection model components.
  size_t text_length = text().length();
  Range range(std::min(model.selection().start(), text_length),
              std::min(model.caret_pos(), text_length));
  // The current model only supports caret positions at valid character indices.
  if (!IsCursorablePosition(range.start()) ||
      !IsCursorablePosition(range.end()))
    return false;
  SelectionModel sel(range, model.caret_affinity());
  bool changed = sel != selection_model_;
  SetSelectionModel(sel);
  return changed;
}

bool RenderText::MoveCursorTo(const Point& point, bool select) {
  SelectionModel position = FindCursorPosition(point);
  if (select)
    position.set_selection_start(selection().start());
  return MoveCursorTo(position);
}

bool RenderText::SelectRange(const Range& range) {
  Range sel(std::min(range.start(), text().length()),
            std::min(range.end(), text().length()));
  if (!IsCursorablePosition(sel.start()) || !IsCursorablePosition(sel.end()))
    return false;
  LogicalCursorDirection affinity =
      (sel.is_reversed() || sel.is_empty()) ? CURSOR_FORWARD : CURSOR_BACKWARD;
  SetSelectionModel(SelectionModel(sel, affinity));
  return true;
}

bool RenderText::IsPointInSelection(const Point& point) {
  if (selection().is_empty())
    return false;
  SelectionModel cursor = FindCursorPosition(point);
  return RangeContainsCaret(
      selection(), cursor.caret_pos(), cursor.caret_affinity());
}

void RenderText::ClearSelection() {
  SetSelectionModel(SelectionModel(cursor_position(),
                                   selection_model_.caret_affinity()));
}

void RenderText::SelectAll(bool reversed) {
  const size_t length = text().length();
  const Range all = reversed ? Range(length, 0) : Range(0, length);
  const bool success = SelectRange(all);
  DCHECK(success);
}

void RenderText::SelectWord() {
  if (obscured_) {
    SelectAll(false);
    return;
  }

  size_t selection_max = selection().GetMax();

  base::i18n::BreakIterator iter(text(), base::i18n::BreakIterator::BREAK_WORD);
  bool success = iter.Init();
  DCHECK(success);
  if (!success)
    return;

  size_t selection_min = selection().GetMin();
  if (selection_min == text().length() && selection_min != 0)
    --selection_min;

  for (; selection_min != 0; --selection_min) {
    if (iter.IsStartOfWord(selection_min) ||
        iter.IsEndOfWord(selection_min))
      break;
  }

  if (selection_min == selection_max && selection_max != text().length())
    ++selection_max;

  for (; selection_max < text().length(); ++selection_max)
    if (iter.IsEndOfWord(selection_max) || iter.IsStartOfWord(selection_max))
      break;

  const bool reversed = selection().is_reversed();
  MoveCursorTo(reversed ? selection_max : selection_min, false);
  MoveCursorTo(reversed ? selection_min : selection_max, true);
}

const Range& RenderText::GetCompositionRange() const {
  return composition_range_;
}

void RenderText::SetCompositionRange(const Range& composition_range) {
  CHECK(!composition_range.IsValid() ||
        Range(0, text_.length()).Contains(composition_range));
  composition_range_.set_end(composition_range.end());
  composition_range_.set_start(composition_range.start());
  ResetLayout();
}

void RenderText::SetColor(SkColor value) {
  colors_.SetValue(value);

#if defined(OS_WIN)
  // TODO(msw): Windows applies colors and decorations in the layout process.
  cached_bounds_and_offset_valid_ = false;
  ResetLayout();
#endif
}

void RenderText::ApplyColor(SkColor value, const Range& range) {
  colors_.ApplyValue(value, range);

#if defined(OS_WIN)
  // TODO(msw): Windows applies colors and decorations in the layout process.
  cached_bounds_and_offset_valid_ = false;
  ResetLayout();
#endif
}

void RenderText::SetStyle(TextStyle style, bool value) {
  styles_[style].SetValue(value);

  // Only invalidate the layout on font changes; not for colors or decorations.
  bool invalidate = (style == BOLD) || (style == ITALIC);
#if defined(OS_WIN)
  // TODO(msw): Windows applies colors and decorations in the layout process.
  invalidate = true;
#endif
  if (invalidate) {
    cached_bounds_and_offset_valid_ = false;
    ResetLayout();
  }
}

void RenderText::ApplyStyle(TextStyle style, bool value, const Range& range) {
  styles_[style].ApplyValue(value, range);

  // Only invalidate the layout on font changes; not for colors or decorations.
  bool invalidate = (style == BOLD) || (style == ITALIC);
#if defined(OS_WIN)
  // TODO(msw): Windows applies colors and decorations in the layout process.
  invalidate = true;
#endif
  if (invalidate) {
    cached_bounds_and_offset_valid_ = false;
    ResetLayout();
  }
}

bool RenderText::GetStyle(TextStyle style) const {
  return (styles_[style].breaks().size() == 1) &&
      styles_[style].breaks().front().second;
}

void RenderText::SetDirectionalityMode(DirectionalityMode mode) {
  if (mode == directionality_mode_)
    return;

  directionality_mode_ = mode;
  text_direction_ = base::i18n::UNKNOWN_DIRECTION;
  cached_bounds_and_offset_valid_ = false;
  ResetLayout();
}

base::i18n::TextDirection RenderText::GetTextDirection() {
  if (text_direction_ == base::i18n::UNKNOWN_DIRECTION) {
    switch (directionality_mode_) {
      case DIRECTIONALITY_FROM_TEXT:
        // Derive the direction from the display text, which differs from text()
        // in the case of obscured (password) textfields.
        text_direction_ =
            base::i18n::GetFirstStrongCharacterDirection(GetLayoutText());
        break;
      case DIRECTIONALITY_FROM_UI:
        text_direction_ = base::i18n::IsRTL() ? base::i18n::RIGHT_TO_LEFT :
                                                base::i18n::LEFT_TO_RIGHT;
        break;
      case DIRECTIONALITY_FORCE_LTR:
        text_direction_ = base::i18n::LEFT_TO_RIGHT;
        break;
      case DIRECTIONALITY_FORCE_RTL:
        text_direction_ = base::i18n::RIGHT_TO_LEFT;
        break;
      default:
        NOTREACHED();
    }
  }

  return text_direction_;
}

VisualCursorDirection RenderText::GetVisualDirectionOfLogicalEnd() {
  return GetTextDirection() == base::i18n::LEFT_TO_RIGHT ?
      CURSOR_RIGHT : CURSOR_LEFT;
}

SizeF RenderText::GetStringSizeF() {
  const Size size = GetStringSize();
  return SizeF(size.width(), size.height());
}

int RenderText::GetContentWidth() {
  return GetStringSize().width() + (cursor_enabled_ ? 1 : 0);
}

int RenderText::GetBaseline() {
  if (baseline_ == kInvalidBaseline)
    baseline_ = DetermineBaselineCenteringText(display_rect(), font_list());
  DCHECK_NE(kInvalidBaseline, baseline_);
  return baseline_;
}

void RenderText::Draw(Canvas* canvas) {
  EnsureLayout();

  if (clip_to_display_rect()) {
    Rect clip_rect(display_rect());
    clip_rect.Inset(ShadowValue::GetMargin(text_shadows_));

    canvas->Save();
    canvas->ClipRect(clip_rect);
  }

  if (!text().empty() && focused())
    DrawSelection(canvas);

  if (cursor_enabled() && cursor_visible() && focused())
    DrawCursor(canvas, selection_model_);

  if (!text().empty())
    DrawVisualText(canvas);

  if (clip_to_display_rect())
    canvas->Restore();
}

void RenderText::DrawCursor(Canvas* canvas, const SelectionModel& position) {
  // Paint cursor. Replace cursor is drawn as rectangle for now.
  // TODO(msw): Draw a better cursor with a better indication of association.
  canvas->FillRect(GetCursorBounds(position, true), cursor_color_);
}

Rect RenderText::GetCursorBounds(const SelectionModel& caret,
                                 bool insert_mode) {
  // TODO(ckocagil): Support multiline. This function should return the height
  //                 of the line the cursor is on. |GetStringSize()| now returns
  //                 the multiline size, eliminate its use here.

  EnsureLayout();

  size_t caret_pos = caret.caret_pos();
  DCHECK(IsCursorablePosition(caret_pos));
  // In overtype mode, ignore the affinity and always indicate that we will
  // overtype the next character.
  LogicalCursorDirection caret_affinity =
      insert_mode ? caret.caret_affinity() : CURSOR_FORWARD;
  int x = 0, width = 1;
  Size size = GetStringSize();
  if (caret_pos == (caret_affinity == CURSOR_BACKWARD ? 0 : text().length())) {
    // The caret is attached to the boundary. Always return a 1-dip width caret,
    // since there is nothing to overtype.
    if ((GetTextDirection() == base::i18n::RIGHT_TO_LEFT) == (caret_pos == 0))
      x = size.width();
  } else {
    size_t grapheme_start = (caret_affinity == CURSOR_FORWARD) ?
        caret_pos : IndexOfAdjacentGrapheme(caret_pos, CURSOR_BACKWARD);
    Range xspan(GetGlyphBounds(grapheme_start));
    if (insert_mode) {
      x = (caret_affinity == CURSOR_BACKWARD) ? xspan.end() : xspan.start();
    } else {  // overtype mode
      x = xspan.GetMin();
      width = xspan.length();
    }
  }
  return Rect(ToViewPoint(Point(x, 0)), Size(width, size.height()));
}

const Rect& RenderText::GetUpdatedCursorBounds() {
  UpdateCachedBoundsAndOffset();
  return cursor_bounds_;
}

size_t RenderText::IndexOfAdjacentGrapheme(size_t index,
                                           LogicalCursorDirection direction) {
  if (index > text().length())
    return text().length();

  EnsureLayout();

  if (direction == CURSOR_FORWARD) {
    while (index < text().length()) {
      index++;
      if (IsCursorablePosition(index))
        return index;
    }
    return text().length();
  }

  while (index > 0) {
    index--;
    if (IsCursorablePosition(index))
      return index;
  }
  return 0;
}

SelectionModel RenderText::GetSelectionModelForSelectionStart() {
  const Range& sel = selection();
  if (sel.is_empty())
    return selection_model_;
  return SelectionModel(sel.start(),
                        sel.is_reversed() ? CURSOR_BACKWARD : CURSOR_FORWARD);
}

void RenderText::SetTextShadows(const ShadowValues& shadows) {
  text_shadows_ = shadows;
}

RenderText::RenderText()
    : horizontal_alignment_(base::i18n::IsRTL() ? ALIGN_RIGHT : ALIGN_LEFT),
      directionality_mode_(DIRECTIONALITY_FROM_TEXT),
      text_direction_(base::i18n::UNKNOWN_DIRECTION),
      cursor_enabled_(true),
      cursor_visible_(false),
      insert_mode_(true),
      cursor_color_(kDefaultColor),
      selection_color_(kDefaultColor),
      selection_background_focused_color_(kDefaultSelectionBackgroundColor),
      focused_(false),
      composition_range_(Range::InvalidRange()),
      colors_(kDefaultColor),
      styles_(NUM_TEXT_STYLES),
      composition_and_selection_styles_applied_(false),
      obscured_(false),
      obscured_reveal_index_(-1),
      truncate_length_(0),
      elide_behavior_(NO_ELIDE),
      multiline_(false),
      fade_head_(false),
      fade_tail_(false),
      background_is_transparent_(false),
      clip_to_display_rect_(true),
      baseline_(kInvalidBaseline),
      cached_bounds_and_offset_valid_(false) {
}

const Vector2d& RenderText::GetUpdatedDisplayOffset() {
  UpdateCachedBoundsAndOffset();
  return display_offset_;
}

SelectionModel RenderText::GetAdjacentSelectionModel(
    const SelectionModel& current,
    BreakType break_type,
    VisualCursorDirection direction) {
  EnsureLayout();

  if (break_type == LINE_BREAK || text().empty())
    return EdgeSelectionModel(direction);
  if (break_type == CHARACTER_BREAK)
    return AdjacentCharSelectionModel(current, direction);
  DCHECK(break_type == WORD_BREAK);
  return AdjacentWordSelectionModel(current, direction);
}

SelectionModel RenderText::EdgeSelectionModel(
    VisualCursorDirection direction) {
  if (direction == GetVisualDirectionOfLogicalEnd())
    return SelectionModel(text().length(), CURSOR_FORWARD);
  return SelectionModel(0, CURSOR_BACKWARD);
}

void RenderText::SetSelectionModel(const SelectionModel& model) {
  DCHECK_LE(model.selection().GetMax(), text().length());
  selection_model_ = model;
  cached_bounds_and_offset_valid_ = false;
}

const base::string16& RenderText::GetLayoutText() const {
  return layout_text_;
}

const BreakList<size_t>& RenderText::GetLineBreaks() {
  if (line_breaks_.max() != 0)
    return line_breaks_;

  const base::string16& layout_text = GetLayoutText();
  const size_t text_length = layout_text.length();
  line_breaks_.SetValue(0);
  line_breaks_.SetMax(text_length);
  base::i18n::BreakIterator iter(layout_text,
                                 base::i18n::BreakIterator::BREAK_LINE);
  const bool success = iter.Init();
  DCHECK(success);
  if (success) {
    do {
      line_breaks_.ApplyValue(iter.pos(), Range(iter.pos(), text_length));
    } while (iter.Advance());
  }
  return line_breaks_;
}

void RenderText::ApplyCompositionAndSelectionStyles() {
  // Save the underline and color breaks to undo the temporary styles later.
  DCHECK(!composition_and_selection_styles_applied_);
  saved_colors_ = colors_;
  saved_underlines_ = styles_[UNDERLINE];

  // Apply an underline to the composition range in |underlines|.
  if (composition_range_.IsValid() && !composition_range_.is_empty())
    styles_[UNDERLINE].ApplyValue(true, composition_range_);

  // Apply the selected text color to the [un-reversed] selection range.
  if (!selection().is_empty() && focused()) {
    const Range range(selection().GetMin(), selection().GetMax());
    colors_.ApplyValue(selection_color_, range);
  }
  composition_and_selection_styles_applied_ = true;
}

void RenderText::UndoCompositionAndSelectionStyles() {
  // Restore the underline and color breaks to undo the temporary styles.
  DCHECK(composition_and_selection_styles_applied_);
  colors_ = saved_colors_;
  styles_[UNDERLINE] = saved_underlines_;
  composition_and_selection_styles_applied_ = false;
}

Vector2d RenderText::GetLineOffset(size_t line_number) {
  Vector2d offset = display_rect().OffsetFromOrigin();
  // TODO(ckocagil): Apply the display offset for multiline scrolling.
  if (!multiline())
    offset.Add(GetUpdatedDisplayOffset());
  else
    offset.Add(Vector2d(0, lines_[line_number].preceding_heights));
  offset.Add(GetAlignmentOffset(line_number));
  return offset;
}

Point RenderText::ToTextPoint(const Point& point) {
  return point - GetLineOffset(0);
  // TODO(ckocagil): Convert multiline view space points to text space.
}

Point RenderText::ToViewPoint(const Point& point) {
  if (!multiline())
    return point + GetLineOffset(0);

  // TODO(ckocagil): Traverse individual line segments for RTL support.
  DCHECK(!lines_.empty());
  int x = point.x();
  size_t line = 0;
  for (; line < lines_.size() && x > lines_[line].size.width(); ++line)
    x -= lines_[line].size.width();
  return Point(x, point.y()) + GetLineOffset(line);
}

std::vector<Rect> RenderText::TextBoundsToViewBounds(const Range& x) {
  std::vector<Rect> rects;

  if (!multiline()) {
    rects.push_back(Rect(ToViewPoint(Point(x.GetMin(), 0)),
                         Size(x.length(), GetStringSize().height())));
    return rects;
  }

  EnsureLayout();

  // Each line segment keeps its position in text coordinates. Traverse all line
  // segments and if the segment intersects with the given range, add the view
  // rect corresponding to the intersection to |rects|.
  for (size_t line = 0; line < lines_.size(); ++line) {
    int line_x = 0;
    const Vector2d offset = GetLineOffset(line);
    for (size_t i = 0; i < lines_[line].segments.size(); ++i) {
      const internal::LineSegment* segment = &lines_[line].segments[i];
      const Range intersection = segment->x_range.Intersect(x);
      if (!intersection.is_empty()) {
        Rect rect(line_x + intersection.start() - segment->x_range.start(),
                  0, intersection.length(), lines_[line].size.height());
        rects.push_back(rect + offset);
      }
      line_x += segment->x_range.length();
    }
  }

  return rects;
}

Vector2d RenderText::GetAlignmentOffset(size_t line_number) {
  // TODO(ckocagil): Enable |lines_| usage in other platforms.
#if defined(OS_WIN)
  DCHECK_LT(line_number, lines_.size());
#endif
  Vector2d offset;
  if (horizontal_alignment_ != ALIGN_LEFT) {
#if defined(OS_WIN)
    const int width = lines_[line_number].size.width() +
        (cursor_enabled_ ? 1 : 0);
#else
    const int width = GetContentWidth();
#endif
    offset.set_x(display_rect().width() - width);
    if (horizontal_alignment_ == ALIGN_CENTER)
      offset.set_x(offset.x() / 2);
  }

  // Vertically center the text.
  if (multiline_) {
    const int text_height = lines_.back().preceding_heights +
        lines_.back().size.height();
    offset.set_y((display_rect_.height() - text_height) / 2);
  } else {
    offset.set_y(GetBaseline() - GetLayoutTextBaseline());
  }

  return offset;
}

void RenderText::ApplyFadeEffects(internal::SkiaTextRenderer* renderer) {
  if (multiline() || (!fade_head() && !fade_tail()))
    return;

  const int display_width = display_rect().width();

  // If the text fits as-is, no need to fade.
  if (GetStringSize().width() <= display_width)
    return;

  int gradient_width = CalculateFadeGradientWidth(font_list(), display_width);
  if (gradient_width == 0)
    return;

  bool fade_left = fade_head();
  bool fade_right = fade_tail();
  // Under RTL, |fade_right| == |fade_head|.
  // TODO(asvitkine): This is currently not based on GetTextDirection() because
  //                  RenderTextWin does not return a direction that's based on
  //                  the text content.
  if (horizontal_alignment_ == ALIGN_RIGHT)
    std::swap(fade_left, fade_right);

  Rect solid_part = display_rect();
  Rect left_part;
  Rect right_part;
  if (fade_left) {
    left_part = solid_part;
    left_part.Inset(0, 0, solid_part.width() - gradient_width, 0);
    solid_part.Inset(gradient_width, 0, 0, 0);
  }
  if (fade_right) {
    right_part = solid_part;
    right_part.Inset(solid_part.width() - gradient_width, 0, 0, 0);
    solid_part.Inset(0, 0, gradient_width, 0);
  }

  Rect text_rect = display_rect();
  text_rect.Inset(GetAlignmentOffset(0).x(), 0, 0, 0);

  // TODO(msw): Use the actual text colors corresponding to each faded part.
  skia::RefPtr<SkShader> shader = CreateFadeShader(
      text_rect, left_part, right_part, colors_.breaks().front().second);
  if (shader)
    renderer->SetShader(shader.get(), display_rect());
}

void RenderText::ApplyTextShadows(internal::SkiaTextRenderer* renderer) {
  skia::RefPtr<SkDrawLooper> looper = CreateShadowDrawLooper(text_shadows_);
  renderer->SetDrawLooper(looper.get());
}

// static
bool RenderText::RangeContainsCaret(const Range& range,
                                    size_t caret_pos,
                                    LogicalCursorDirection caret_affinity) {
  // NB: exploits unsigned wraparound (WG14/N1124 section 6.2.5 paragraph 9).
  size_t adjacent = (caret_affinity == CURSOR_BACKWARD) ?
      caret_pos - 1 : caret_pos + 1;
  return range.Contains(Range(caret_pos, adjacent));
}

void RenderText::MoveCursorTo(size_t position, bool select) {
  size_t cursor = std::min(position, text().length());
  if (IsCursorablePosition(cursor))
    SetSelectionModel(SelectionModel(
        Range(select ? selection().start() : cursor, cursor),
        (cursor == 0) ? CURSOR_FORWARD : CURSOR_BACKWARD));
}

void RenderText::UpdateLayoutText() {
  layout_text_.clear();
  line_breaks_.SetMax(0);

  if (obscured_) {
    size_t obscured_text_length =
        static_cast<size_t>(gfx::UTF16IndexToOffset(text_, 0, text_.length()));
    layout_text_.assign(obscured_text_length, kPasswordReplacementChar);

    if (obscured_reveal_index_ >= 0 &&
        obscured_reveal_index_ < static_cast<int>(text_.length())) {
      // Gets the index range in |text_| to be revealed.
      size_t start = obscured_reveal_index_;
      U16_SET_CP_START(text_.data(), 0, start);
      size_t end = start;
      UChar32 unused_char;
      U16_NEXT(text_.data(), end, text_.length(), unused_char);

      // Gets the index in |layout_text_| to be replaced.
      const size_t cp_start =
          static_cast<size_t>(gfx::UTF16IndexToOffset(text_, 0, start));
      if (layout_text_.length() > cp_start)
        layout_text_.replace(cp_start, 1, text_.substr(start, end - start));
    }
  } else {
    layout_text_ = text_;
  }

  const base::string16& text = layout_text_;
  if (truncate_length_ > 0 && truncate_length_ < text.length()) {
    // Truncate the text at a valid character break and append an ellipsis.
    icu::StringCharacterIterator iter(text.c_str());
    iter.setIndex32(truncate_length_ - 1);
    layout_text_.assign(text.substr(0, iter.getIndex()) + gfx::kEllipsisUTF16);
  }

  if (elide_behavior_ != NO_ELIDE && display_rect_.width() > 0 &&
      !layout_text_.empty() && GetContentWidth() > display_rect_.width()) {
    // This doesn't trim styles so ellipsis may get rendered as a different
    // style than the preceding text. See crbug.com/327850.
    layout_text_.assign(ElideText(layout_text_));
  }

  ResetLayout();
}

// TODO(skanuj): Fix code duplication with ElideText in ui/gfx/text_elider.cc
// See crbug.com/327846
base::string16 RenderText::ElideText(const base::string16& text) {
  const bool insert_ellipsis = (elide_behavior_ != TRUNCATE_AT_END);
  // Create a RenderText copy with attributes that affect the rendering width.
  scoped_ptr<RenderText> render_text(CreateInstance());
  render_text->SetFontList(font_list_);
  render_text->SetDirectionalityMode(directionality_mode_);
  render_text->SetCursorEnabled(cursor_enabled_);

  render_text->styles_ = styles_;
  render_text->colors_ = colors_;
  render_text->SetText(text);
  const int current_text_pixel_width = render_text->GetContentWidth();

  const base::string16 ellipsis = base::string16(gfx::kEllipsisUTF16);
  const bool elide_in_middle = false;
  const bool elide_at_beginning = false;
  StringSlicer slicer(text, ellipsis, elide_in_middle, elide_at_beginning);

  // Pango will return 0 width for absurdly long strings. Cut the string in
  // half and try again.
  // This is caused by an int overflow in Pango (specifically, in
  // pango_glyph_string_extents_range). It's actually more subtle than just
  // returning 0, since on super absurdly long strings, the int can wrap and
  // return positive numbers again. Detecting that is probably not worth it
  // (eliding way too much from a ridiculous string is probably still
  // ridiculous), but we should check other widths for bogus values as well.
  if (current_text_pixel_width <= 0 && !text.empty())
    return ElideText(slicer.CutString(text.length() / 2, insert_ellipsis));

  if (current_text_pixel_width <= display_rect_.width())
    return text;

  render_text->SetText(base::string16());
  render_text->SetText(ellipsis);
  const int ellipsis_width = render_text->GetContentWidth();

  if (insert_ellipsis && (ellipsis_width >= display_rect_.width()))
    return base::string16();

  // Use binary search to compute the elided text.
  size_t lo = 0;
  size_t hi = text.length() - 1;
  const base::i18n::TextDirection text_direction = GetTextDirection();
  for (size_t guess = (lo + hi) / 2; lo <= hi; guess = (lo + hi) / 2) {
    // Restore styles and colors. They will be truncated to size by SetText.
    render_text->styles_ = styles_;
    render_text->colors_ = colors_;
    base::string16 new_text = slicer.CutString(guess, false);
    render_text->SetText(new_text);

    // This has to be an additional step so that the ellipsis is rendered with
    // same style as trailing part of the text.
    if (insert_ellipsis) {
      // When ellipsis follows text whose directionality is not the same as that
      // of the whole text, it will be rendered with the directionality of the
      // whole text. Since we want ellipsis to indicate continuation of the
      // preceding text, we force the directionality of ellipsis to be same as
      // the preceding text using LTR or RTL markers.
      base::i18n::TextDirection trailing_text_direction =
          base::i18n::GetLastStrongCharacterDirection(new_text);
      new_text.append(ellipsis);
      if (trailing_text_direction != text_direction) {
        if (trailing_text_direction == base::i18n::LEFT_TO_RIGHT)
          new_text += base::i18n::kLeftToRightMark;
        else
          new_text += base::i18n::kRightToLeftMark;
      }
      render_text->SetText(new_text);
    }

    // We check the width of the whole desired string at once to ensure we
    // handle kerning/ligatures/etc. correctly.
    const int guess_width = render_text->GetContentWidth();
    if (guess_width == display_rect_.width())
      break;
    if (guess_width > display_rect_.width()) {
      hi = guess - 1;
      // Move back if we are on loop terminating condition, and guess is wider
      // than available.
      if (hi < lo)
        lo = hi;
    } else {
      lo = guess + 1;
    }
  }

  return render_text->text();
}

void RenderText::UpdateCachedBoundsAndOffset() {
  if (cached_bounds_and_offset_valid_)
    return;

  // TODO(ckocagil): Add support for scrolling multiline text.

  // First, set the valid flag true to calculate the current cursor bounds using
  // the stale |display_offset_|. Applying |delta_offset| at the end of this
  // function will set |cursor_bounds_| and |display_offset_| to correct values.
  cached_bounds_and_offset_valid_ = true;
  if (cursor_enabled())
    cursor_bounds_ = GetCursorBounds(selection_model_, insert_mode_);

  // Update |display_offset_| to ensure the current cursor is visible.
  const int display_width = display_rect_.width();
  const int content_width = GetContentWidth();

  int delta_x = 0;
  if (content_width <= display_width || !cursor_enabled()) {
    // Don't pan if the text fits in the display width or when the cursor is
    // disabled.
    delta_x = -display_offset_.x();
  } else if (cursor_bounds_.right() > display_rect_.right()) {
    // TODO(xji): when the character overflow is a RTL character, currently, if
    // we pan cursor at the rightmost position, the entered RTL character is not
    // displayed. Should pan cursor to show the last logical characters.
    //
    // Pan to show the cursor when it overflows to the right.
    delta_x = display_rect_.right() - cursor_bounds_.right();
  } else if (cursor_bounds_.x() < display_rect_.x()) {
    // TODO(xji): have similar problem as above when overflow character is a
    // LTR character.
    //
    // Pan to show the cursor when it overflows to the left.
    delta_x = display_rect_.x() - cursor_bounds_.x();
  } else if (display_offset_.x() != 0) {
    // Reduce the pan offset to show additional overflow text when the display
    // width increases.
    const int negate_rtl = horizontal_alignment_ == ALIGN_RIGHT ? -1 : 1;
    const int offset = negate_rtl * display_offset_.x();
    if (display_width > (content_width + offset)) {
      delta_x = negate_rtl * (display_width - (content_width + offset));
    }
  }

  Vector2d delta_offset(delta_x, 0);
  display_offset_ += delta_offset;
  cursor_bounds_ += delta_offset;
}

void RenderText::DrawSelection(Canvas* canvas) {
  const std::vector<Rect> sel = GetSubstringBounds(selection());
  for (std::vector<Rect>::const_iterator i = sel.begin(); i < sel.end(); ++i)
    canvas->FillRect(*i, selection_background_focused_color_);
}

}  // namespace gfx
/* [<][>][^][v][top][bottom][index][help] */
root/ui/gfx/render_text.cc

DEFINITIONS
