ui/gfx/render_text_mac.cc

   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 #include "ui/gfx/render_text_mac.h"
   6
   7 #include <ApplicationServices/ApplicationServices.h>
   8
   9 #include <algorithm>
  10 #include <cmath>
  11 #include <utility>
  12
  13 #include "base/mac/foundation_util.h"
  14 #include "base/mac/scoped_cftyperef.h"
  15 #include "base/strings/sys_string_conversions.h"
  16 #include "skia/ext/skia_utils_mac.h"
  17
  18 namespace gfx {
  19
  20 RenderTextMac::RenderTextMac() : common_baseline_(0), runs_valid_(false) {
  21 }
  22
  23 RenderTextMac::~RenderTextMac() {
  24 }
  25
  26 Size RenderTextMac::GetStringSize() {
  27   EnsureLayout();
  28   return string_size_;
  29 }
  30
  31 int RenderTextMac::GetBaseline() {
  32   EnsureLayout();
  33   return common_baseline_;
  34 }
  35
  36 SelectionModel RenderTextMac::FindCursorPosition(const Point& point) {
  37   // TODO(asvitkine): Implement this. http://crbug.com/131618
  38   return SelectionModel();
  39 }
  40
  41 std::vector<RenderText::FontSpan> RenderTextMac::GetFontSpansForTesting() {
  42   EnsureLayout();
  43   if (!runs_valid_)
  44     ComputeRuns();
  45
  46   std::vector<RenderText::FontSpan> spans;
  47   for (size_t i = 0; i < runs_.size(); ++i) {
  48     gfx::Font font(runs_[i].font_name, runs_[i].text_size);
  49     const CFRange cf_range = CTRunGetStringRange(runs_[i].ct_run);
  50     const ui::Range range(cf_range.location,
  51                           cf_range.location + cf_range.length);
  52     spans.push_back(RenderText::FontSpan(font, range));
  53   }
  54
  55   return spans;
  56 }
  57
  58 SelectionModel RenderTextMac::AdjacentCharSelectionModel(
  59     const SelectionModel& selection,
  60     VisualCursorDirection direction) {
  61   // TODO(asvitkine): Implement this. http://crbug.com/131618
  62   return SelectionModel();
  63 }
  64
  65 SelectionModel RenderTextMac::AdjacentWordSelectionModel(
  66     const SelectionModel& selection,
  67     VisualCursorDirection direction) {
  68   // TODO(asvitkine): Implement this. http://crbug.com/131618
  69   return SelectionModel();
  70 }
  71
  72 ui::Range RenderTextMac::GetGlyphBounds(size_t index) {
  73   // TODO(asvitkine): Implement this. http://crbug.com/131618
  74   return ui::Range();
  75 }
  76
  77 std::vector<Rect> RenderTextMac::GetSubstringBounds(const ui::Range& range) {
  78   // TODO(asvitkine): Implement this. http://crbug.com/131618
  79   return std::vector<Rect>();
  80 }
  81
  82 size_t RenderTextMac::TextIndexToLayoutIndex(size_t index) const {
  83   // TODO(asvitkine): Implement this. http://crbug.com/131618
  84   return index;
  85 }
  86
  87 size_t RenderTextMac::LayoutIndexToTextIndex(size_t index) const {
  88   // TODO(asvitkine): Implement this. http://crbug.com/131618
  89   return index;
  90 }
  91
  92 bool RenderTextMac::IsCursorablePosition(size_t position) {
  93   // TODO(asvitkine): Implement this. http://crbug.com/131618
  94   return true;
  95 }
  96
  97 void RenderTextMac::ResetLayout() {
  98   line_.reset();
  99   attributes_.reset();
 100   runs_.clear();
 101   runs_valid_ = false;
 102 }
 103
 104 void RenderTextMac::EnsureLayout() {
 105   if (line_.get())
 106     return;
 107   runs_.clear();
 108   runs_valid_ = false;
 109
 110   const Font& font = GetPrimaryFont();
 111   base::ScopedCFTypeRef<CFStringRef> font_name_cf_string(
 112       base::SysUTF8ToCFStringRef(font.GetFontName()));
 113   base::ScopedCFTypeRef<CTFontRef> ct_font(
 114       CTFontCreateWithName(font_name_cf_string, font.GetFontSize(), NULL));
 115
 116   const void* keys[] = { kCTFontAttributeName };
 117   const void* values[] = { ct_font };
 118   base::ScopedCFTypeRef<CFDictionaryRef> attributes(
 119       CFDictionaryCreate(NULL,
 120                          keys,
 121                          values,
 122                          arraysize(keys),
 123                          NULL,
 124                          &kCFTypeDictionaryValueCallBacks));
 125
 126   base::ScopedCFTypeRef<CFStringRef> cf_text(
 127       base::SysUTF16ToCFStringRef(text()));
 128   base::ScopedCFTypeRef<CFAttributedStringRef> attr_text(
 129       CFAttributedStringCreate(NULL, cf_text, attributes));
 130   base::ScopedCFTypeRef<CFMutableAttributedStringRef> attr_text_mutable(
 131       CFAttributedStringCreateMutableCopy(NULL, 0, attr_text));
 132
 133   // TODO(asvitkine|msw): Respect GetTextDirection(), which may not match the
 134   // natural text direction. See kCTTypesetterOptionForcedEmbeddingLevel, etc.
 135
 136   ApplyStyles(attr_text_mutable, ct_font);
 137   line_.reset(CTLineCreateWithAttributedString(attr_text_mutable));
 138
 139   CGFloat ascent = 0;
 140   CGFloat descent = 0;
 141   CGFloat leading = 0;
 142   // TODO(asvitkine): Consider using CTLineGetBoundsWithOptions() on 10.8+.
 143   double width = CTLineGetTypographicBounds(line_, &ascent, &descent, &leading);
 144   // Ensure ascent and descent are not smaller than ones of the font list.
 145   // Keep them tall enough to draw often-used characters.
 146   // For example, if a text field contains a Japanese character, which is
 147   // smaller than Latin ones, and then later a Latin one is inserted, this
 148   // ensures that the text baseline does not shift.
 149   CGFloat font_list_height = font_list().GetHeight();
 150   CGFloat font_list_baseline = font_list().GetBaseline();
 151   ascent = std::max(ascent, font_list_baseline);
 152   descent = std::max(descent, font_list_height - font_list_baseline);
 153   string_size_ = Size(width, ascent + descent + leading);
 154   common_baseline_ = ascent;
 155 }
 156
 157 void RenderTextMac::DrawVisualText(Canvas* canvas) {
 158   DCHECK(line_);
 159   if (!runs_valid_)
 160     ComputeRuns();
 161
 162   internal::SkiaTextRenderer renderer(canvas);
 163   ApplyFadeEffects(&renderer);
 164   ApplyTextShadows(&renderer);
 165
 166   for (size_t i = 0; i < runs_.size(); ++i) {
 167     const TextRun& run = runs_[i];
 168     renderer.SetForegroundColor(run.foreground);
 169     renderer.SetTextSize(run.text_size);
 170     renderer.SetFontFamilyWithStyle(run.font_name, run.font_style);
 171     renderer.DrawPosText(&run.glyph_positions[0], &run.glyphs[0],
 172                          run.glyphs.size());
 173     renderer.DrawDecorations(run.origin.x(), run.origin.y(), run.width,
 174                              run.underline, run.strike, run.diagonal_strike);
 175   }
 176 }
 177
 178 RenderTextMac::TextRun::TextRun()
 179     : ct_run(NULL),
 180       origin(SkPoint::Make(0, 0)),
 181       width(0),
 182       font_style(Font::NORMAL),
 183       text_size(0),
 184       foreground(SK_ColorBLACK),
 185       underline(false),
 186       strike(false),
 187       diagonal_strike(false) {
 188 }
 189
 190 RenderTextMac::TextRun::~TextRun() {
 191 }
 192
 193 void RenderTextMac::ApplyStyles(CFMutableAttributedStringRef attr_string,
 194                                 CTFontRef font) {
 195   // Temporarily apply composition underlines and selection colors.
 196   ApplyCompositionAndSelectionStyles();
 197
 198   // Note: CFAttributedStringSetAttribute() does not appear to retain the values
 199   // passed in, as can be verified via CFGetRetainCount(). To ensure the
 200   // attribute objects do not leak, they are saved to |attributes_|.
 201   // Clear the attributes storage.
 202   attributes_.reset(CFArrayCreateMutable(NULL, 0, &kCFTypeArrayCallBacks));
 203
 204   // https://developer.apple.com/library/mac/#documentation/Carbon/Reference/CoreText_StringAttributes_Ref/Reference/reference.html
 205   internal::StyleIterator style(colors(), styles());
 206   const size_t layout_text_length = GetLayoutText().length();
 207   for (size_t i = 0, end = 0; i < layout_text_length; i = end) {
 208     end = TextIndexToLayoutIndex(style.GetRange().end());
 209     const CFRange range = CFRangeMake(i, end - i);
 210     base::ScopedCFTypeRef<CGColorRef> foreground(
 211         gfx::CGColorCreateFromSkColor(style.color()));
 212     CFAttributedStringSetAttribute(attr_string, range,
 213         kCTForegroundColorAttributeName, foreground);
 214     CFArrayAppendValue(attributes_, foreground);
 215
 216     if (style.style(UNDERLINE)) {
 217       CTUnderlineStyle value = kCTUnderlineStyleSingle;
 218       base::ScopedCFTypeRef<CFNumberRef> underline_value(
 219           CFNumberCreate(NULL, kCFNumberSInt32Type, &value));
 220       CFAttributedStringSetAttribute(attr_string, range,
 221                                      kCTUnderlineStyleAttributeName,
 222                                      underline_value);
 223       CFArrayAppendValue(attributes_, underline_value);
 224     }
 225
 226     const int traits = (style.style(BOLD) ? kCTFontBoldTrait : 0) |
 227                        (style.style(ITALIC) ? kCTFontItalicTrait : 0);
 228     if (traits != 0) {
 229       base::ScopedCFTypeRef<CTFontRef> styled_font(
 230           CTFontCreateCopyWithSymbolicTraits(font, 0.0, NULL, traits, traits));
 231       // TODO(asvitkine): Handle |styled_font| == NULL case better.
 232       if (styled_font) {
 233         CFAttributedStringSetAttribute(attr_string, range, kCTFontAttributeName,
 234                                        styled_font);
 235         CFArrayAppendValue(attributes_, styled_font);
 236       }
 237     }
 238
 239     style.UpdatePosition(LayoutIndexToTextIndex(end));
 240   }
 241
 242   // Undo the temporarily applied composition underlines and selection colors.
 243   UndoCompositionAndSelectionStyles();
 244 }
 245
 246 void RenderTextMac::ComputeRuns() {
 247   DCHECK(line_);
 248
 249   CFArrayRef ct_runs = CTLineGetGlyphRuns(line_);
 250   const CFIndex ct_runs_count = CFArrayGetCount(ct_runs);
 251
 252   // TODO(asvitkine): Don't use GetTextOffset() until draw time, since it may be
 253   // updated based on alignment changes without resetting the layout.
 254   gfx::Vector2d text_offset = GetTextOffset();
 255   // Skia will draw glyphs with respect to the baseline.
 256   text_offset += gfx::Vector2d(0, common_baseline_);
 257
 258   const SkScalar x = SkIntToScalar(text_offset.x());
 259   const SkScalar y = SkIntToScalar(text_offset.y());
 260   SkPoint run_origin = SkPoint::Make(x, y);
 261
 262   const CFRange empty_cf_range = CFRangeMake(0, 0);
 263   for (CFIndex i = 0; i < ct_runs_count; ++i) {
 264     CTRunRef ct_run =
 265         base::mac::CFCast<CTRunRef>(CFArrayGetValueAtIndex(ct_runs, i));
 266     const size_t glyph_count = CTRunGetGlyphCount(ct_run);
 267     const double run_width =
 268         CTRunGetTypographicBounds(ct_run, empty_cf_range, NULL, NULL, NULL);
 269     if (glyph_count == 0) {
 270       run_origin.offset(run_width, 0);
 271       continue;
 272     }
 273
 274     runs_.push_back(TextRun());
 275     TextRun* run = &runs_.back();
 276     run->ct_run = ct_run;
 277     run->origin = run_origin;
 278     run->width = run_width;
 279     run->glyphs.resize(glyph_count);
 280     CTRunGetGlyphs(ct_run, empty_cf_range, &run->glyphs[0]);
 281     // CTRunGetGlyphs() sometimes returns glyphs with value 65535 and zero
 282     // width (this has been observed at the beginning of a string containing
 283     // Arabic content). Passing these to Skia will trigger an assertion;
 284     // instead set their values to 0.
 285     for (size_t glyph = 0; glyph < glyph_count; glyph++) {
 286       if (run->glyphs[glyph] == 65535)
 287         run->glyphs[glyph] = 0;
 288     }
 289
 290     run->glyph_positions.resize(glyph_count);
 291     const CGPoint* positions_ptr = CTRunGetPositionsPtr(ct_run);
 292     std::vector<CGPoint> positions;
 293     if (positions_ptr == NULL) {
 294       positions.resize(glyph_count);
 295       CTRunGetPositions(ct_run, empty_cf_range, &positions[0]);
 296       positions_ptr = &positions[0];
 297     }
 298     for (size_t glyph = 0; glyph < glyph_count; glyph++) {
 299       SkPoint* point = &run->glyph_positions[glyph];
 300       point->set(x + SkDoubleToScalar(positions_ptr[glyph].x),
 301                  y + SkDoubleToScalar(positions_ptr[glyph].y));
 302     }
 303
 304     // TODO(asvitkine): Style boundaries are not necessarily per-run. Handle
 305     //                  this better. Also, support strike and diagonal_strike.
 306     CFDictionaryRef attributes = CTRunGetAttributes(ct_run);
 307     CTFontRef ct_font =
 308         base::mac::GetValueFromDictionary<CTFontRef>(attributes,
 309                                                      kCTFontAttributeName);
 310     base::ScopedCFTypeRef<CFStringRef> font_name_ref(
 311         CTFontCopyFamilyName(ct_font));
 312     run->font_name = base::SysCFStringRefToUTF8(font_name_ref);
 313     run->text_size = CTFontGetSize(ct_font);
 314
 315     CTFontSymbolicTraits traits = CTFontGetSymbolicTraits(ct_font);
 316     if (traits & kCTFontBoldTrait)
 317       run->font_style |= Font::BOLD;
 318     if (traits & kCTFontItalicTrait)
 319       run->font_style |= Font::ITALIC;
 320
 321     const CGColorRef foreground =
 322         base::mac::GetValueFromDictionary<CGColorRef>(
 323             attributes, kCTForegroundColorAttributeName);
 324     if (foreground)
 325       run->foreground = gfx::CGColorRefToSkColor(foreground);
 326
 327     const CFNumberRef underline =
 328         base::mac::GetValueFromDictionary<CFNumberRef>(
 329             attributes, kCTUnderlineStyleAttributeName);
 330     CTUnderlineStyle value = kCTUnderlineStyleNone;
 331     if (underline && CFNumberGetValue(underline, kCFNumberSInt32Type, &value))
 332       run->underline = (value == kCTUnderlineStyleSingle);
 333
 334     run_origin.offset(run_width, 0);
 335   }
 336   runs_valid_ = true;
 337 }
 338
 339 RenderText* RenderText::CreateInstance() {
 340   return new RenderTextMac;
 341 }
 342
 343 }  // namespace gfx