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/platform_font_win.h" 6 7 #include <windows.h> 8 #include <math.h> 9 10 #include <algorithm> 11 #include <string> 12 13 #include "base/logging.h" 14 #include "base/strings/string_util.h" 15 #include "base/strings/sys_string_conversions.h" 16 #include "base/strings/utf_string_conversions.h" 17 #include "base/win/scoped_hdc.h" 18 #include "base/win/scoped_select_object.h" 19 #include "base/win/win_util.h" 20 #include "ui/base/win/scoped_set_map_mode.h" 21 #include "ui/gfx/canvas.h" 22 #include "ui/gfx/font.h" 23 24 namespace { 25 26 // If the tmWeight field of a TEXTMETRIC structure has a value >= this, the 27 // font is bold. 28 const int kTextMetricWeightBold = 700; 29 30 // Returns the minimum font size, using the minimum size callback, if set. 31 int GetMinimumFontSize() { 32 int min_font_size = 0; 33 if (gfx::PlatformFontWin::get_minimum_font_size_callback) 34 min_font_size = gfx::PlatformFontWin::get_minimum_font_size_callback(); 35 return min_font_size; 36 } 37 38 // Returns either minimum font allowed for a current locale or 39 // lf_height + size_delta value. 40 int AdjustFontSize(int lf_height, int size_delta) { 41 if (lf_height < 0) { 42 lf_height -= size_delta; 43 } else { 44 lf_height += size_delta; 45 } 46 const int min_font_size = GetMinimumFontSize(); 47 // Make sure lf_height is not smaller than allowed min font size for current 48 // locale. 49 if (abs(lf_height) < min_font_size) { 50 return lf_height < 0 ? -min_font_size : min_font_size; 51 } else { 52 return lf_height; 53 } 54 } 55 56 // Sets style properties on |font_info| based on |font_style|. 57 void SetLogFontStyle(int font_style, LOGFONT* font_info) { 58 font_info->lfUnderline = (font_style & gfx::Font::UNDERLINE) != 0; 59 font_info->lfItalic = (font_style & gfx::Font::ITALIC) != 0; 60 font_info->lfWeight = (font_style & gfx::Font::BOLD) ? FW_BOLD : FW_NORMAL; 61 } 62 63 } // namespace 64 65 namespace gfx { 66 67 // static 68 PlatformFontWin::HFontRef* PlatformFontWin::base_font_ref_; 69 70 // static 71 PlatformFontWin::AdjustFontCallback 72 PlatformFontWin::adjust_font_callback = NULL; 73 PlatformFontWin::GetMinimumFontSizeCallback 74 PlatformFontWin::get_minimum_font_size_callback = NULL; 75 76 //////////////////////////////////////////////////////////////////////////////// 77 // PlatformFontWin, public 78 79 PlatformFontWin::PlatformFontWin() : font_ref_(GetBaseFontRef()) { 80 } 81 82 PlatformFontWin::PlatformFontWin(NativeFont native_font) { 83 InitWithCopyOfHFONT(native_font); 84 } 85 86 PlatformFontWin::PlatformFontWin(const std::string& font_name, 87 int font_size) { 88 InitWithFontNameAndSize(font_name, font_size); 89 } 90 91 Font PlatformFontWin::DeriveFontWithHeight(int height, int style) { 92 DCHECK_GE(height, 0); 93 if (GetHeight() == height && GetStyle() == style) 94 return Font(this); 95 96 // CreateFontIndirect() doesn't return the largest size for the given height 97 // when decreasing the height. Iterate to find it. 98 if (GetHeight() > height) { 99 const int min_font_size = GetMinimumFontSize(); 100 Font font = DeriveFont(-1, style); 101 int font_height = font.GetHeight(); 102 int font_size = font.GetFontSize(); 103 while (font_height > height && font_size != min_font_size) { 104 font = font.DeriveFont(-1, style); 105 if (font_height == font.GetHeight() && font_size == font.GetFontSize()) 106 break; 107 font_height = font.GetHeight(); 108 font_size = font.GetFontSize(); 109 } 110 return font; 111 } 112 113 LOGFONT font_info; 114 GetObject(GetNativeFont(), sizeof(LOGFONT), &font_info); 115 font_info.lfHeight = height; 116 SetLogFontStyle(style, &font_info); 117 118 HFONT hfont = CreateFontIndirect(&font_info); 119 return Font(new PlatformFontWin(CreateHFontRef(hfont))); 120 } 121 122 //////////////////////////////////////////////////////////////////////////////// 123 // PlatformFontWin, PlatformFont implementation: 124 125 Font PlatformFontWin::DeriveFont(int size_delta, int style) const { 126 LOGFONT font_info; 127 GetObject(GetNativeFont(), sizeof(LOGFONT), &font_info); 128 const int requested_font_size = font_ref_->requested_font_size(); 129 font_info.lfHeight = AdjustFontSize(-requested_font_size, size_delta); 130 SetLogFontStyle(style, &font_info); 131 132 HFONT hfont = CreateFontIndirect(&font_info); 133 return Font(new PlatformFontWin(CreateHFontRef(hfont))); 134 } 135 136 int PlatformFontWin::GetHeight() const { 137 return font_ref_->height(); 138 } 139 140 int PlatformFontWin::GetBaseline() const { 141 return font_ref_->baseline(); 142 } 143 144 int PlatformFontWin::GetAverageCharacterWidth() const { 145 return font_ref_->ave_char_width(); 146 } 147 148 int PlatformFontWin::GetStringWidth(const base::string16& text) const { 149 return Canvas::GetStringWidth(text, 150 Font(const_cast<PlatformFontWin*>(this))); 151 } 152 153 int PlatformFontWin::GetExpectedTextWidth(int length) const { 154 return length * std::min(font_ref_->GetDluBaseX(), 155 GetAverageCharacterWidth()); 156 } 157 158 int PlatformFontWin::GetStyle() const { 159 return font_ref_->style(); 160 } 161 162 std::string PlatformFontWin::GetFontName() const { 163 return font_ref_->font_name(); 164 } 165 166 std::string PlatformFontWin::GetLocalizedFontName() const { 167 base::win::ScopedCreateDC memory_dc(CreateCompatibleDC(NULL)); 168 if (!memory_dc.Get()) 169 return GetFontName(); 170 171 // When a font has a localized name for a language matching the system 172 // locale, GetTextFace() returns the localized name. 173 base::win::ScopedSelectObject font(memory_dc, font_ref_->hfont()); 174 wchar_t localized_font_name[LF_FACESIZE]; 175 int length = GetTextFace(memory_dc, arraysize(localized_font_name), 176 &localized_font_name[0]); 177 if (length <= 0) 178 return GetFontName(); 179 return base::SysWideToUTF8(localized_font_name); 180 } 181 182 int PlatformFontWin::GetFontSize() const { 183 return font_ref_->font_size(); 184 } 185 186 NativeFont PlatformFontWin::GetNativeFont() const { 187 return font_ref_->hfont(); 188 } 189 190 //////////////////////////////////////////////////////////////////////////////// 191 // Font, private: 192 193 void PlatformFontWin::InitWithCopyOfHFONT(HFONT hfont) { 194 DCHECK(hfont); 195 LOGFONT font_info; 196 GetObject(hfont, sizeof(LOGFONT), &font_info); 197 font_ref_ = CreateHFontRef(CreateFontIndirect(&font_info)); 198 } 199 200 void PlatformFontWin::InitWithFontNameAndSize(const std::string& font_name, 201 int font_size) { 202 HFONT hf = ::CreateFont(-font_size, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 203 UTF8ToUTF16(font_name).c_str()); 204 font_ref_ = CreateHFontRef(hf); 205 } 206 207 // static 208 PlatformFontWin::HFontRef* PlatformFontWin::GetBaseFontRef() { 209 if (base_font_ref_ == NULL) { 210 NONCLIENTMETRICS metrics; 211 base::win::GetNonClientMetrics(&metrics); 212 213 if (adjust_font_callback) 214 adjust_font_callback(&metrics.lfMessageFont); 215 metrics.lfMessageFont.lfHeight = 216 AdjustFontSize(metrics.lfMessageFont.lfHeight, 0); 217 HFONT font = CreateFontIndirect(&metrics.lfMessageFont); 218 DLOG_ASSERT(font); 219 base_font_ref_ = PlatformFontWin::CreateHFontRef(font); 220 // base_font_ref_ is global, up the ref count so it's never deleted. 221 base_font_ref_->AddRef(); 222 } 223 return base_font_ref_; 224 } 225 226 PlatformFontWin::HFontRef* PlatformFontWin::CreateHFontRef(HFONT font) { 227 TEXTMETRIC font_metrics; 228 229 { 230 base::win::ScopedGetDC screen_dc(NULL); 231 base::win::ScopedSelectObject scoped_font(screen_dc, font); 232 ui::ScopedSetMapMode mode(screen_dc, MM_TEXT); 233 GetTextMetrics(screen_dc, &font_metrics); 234 } 235 236 const int height = std::max<int>(1, font_metrics.tmHeight); 237 const int baseline = std::max<int>(1, font_metrics.tmAscent); 238 const int ave_char_width = std::max<int>(1, font_metrics.tmAveCharWidth); 239 const int font_size = 240 std::max<int>(1, font_metrics.tmHeight - font_metrics.tmInternalLeading); 241 int style = 0; 242 if (font_metrics.tmItalic) 243 style |= Font::ITALIC; 244 if (font_metrics.tmUnderlined) 245 style |= Font::UNDERLINE; 246 if (font_metrics.tmWeight >= kTextMetricWeightBold) 247 style |= Font::BOLD; 248 249 return new HFontRef(font, font_size, height, baseline, ave_char_width, style); 250 } 251 252 PlatformFontWin::PlatformFontWin(HFontRef* hfont_ref) : font_ref_(hfont_ref) { 253 } 254 255 //////////////////////////////////////////////////////////////////////////////// 256 // PlatformFontWin::HFontRef: 257 258 PlatformFontWin::HFontRef::HFontRef(HFONT hfont, 259 int font_size, 260 int height, 261 int baseline, 262 int ave_char_width, 263 int style) 264 : hfont_(hfont), 265 font_size_(font_size), 266 height_(height), 267 baseline_(baseline), 268 ave_char_width_(ave_char_width), 269 style_(style), 270 dlu_base_x_(-1), 271 requested_font_size_(font_size) { 272 DLOG_ASSERT(hfont); 273 274 LOGFONT font_info; 275 GetObject(hfont_, sizeof(LOGFONT), &font_info); 276 font_name_ = UTF16ToUTF8(base::string16(font_info.lfFaceName)); 277 if (font_info.lfHeight < 0) 278 requested_font_size_ = -font_info.lfHeight; 279 } 280 281 int PlatformFontWin::HFontRef::GetDluBaseX() { 282 if (dlu_base_x_ != -1) 283 return dlu_base_x_; 284 285 base::win::ScopedGetDC screen_dc(NULL); 286 base::win::ScopedSelectObject font(screen_dc, hfont_); 287 ui::ScopedSetMapMode mode(screen_dc, MM_TEXT); 288 289 // Yes, this is how Microsoft recommends calculating the dialog unit 290 // conversions. See: http://support.microsoft.com/kb/125681 291 SIZE ave_text_size; 292 GetTextExtentPoint32(screen_dc, 293 L"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz", 294 52, &ave_text_size); 295 dlu_base_x_ = (ave_text_size.cx / 26 + 1) / 2; 296 297 DCHECK_NE(dlu_base_x_, -1); 298 return dlu_base_x_; 299 } 300 301 PlatformFontWin::HFontRef::~HFontRef() { 302 DeleteObject(hfont_); 303 } 304 305 //////////////////////////////////////////////////////////////////////////////// 306 // PlatformFont, public: 307 308 // static 309 PlatformFont* PlatformFont::CreateDefault() { 310 return new PlatformFontWin; 311 } 312 313 // static 314 PlatformFont* PlatformFont::CreateFromNativeFont(NativeFont native_font) { 315 return new PlatformFontWin(native_font); 316 } 317 318 // static 319 PlatformFont* PlatformFont::CreateFromNameAndSize(const std::string& font_name, 320 int font_size) { 321 return new PlatformFontWin(font_name, font_size); 322 } 323 324 } // namespace gfx 325