Use the correct font metrics in base PlatformFontWin if DirectWrite is used in the browser for font…

ui/gfx/platform_font_win.cc

 // 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/platform_font_win.h"
 
 #include <windows.h>
 #include <math.h>
 
 #include <algorithm>
 #include <string>
 
 #include "base/logging.h"
 #include "base/macros.h"
 #include "base/strings/string_util.h"
 #include "base/strings/sys_string_conversions.h"
 #include "base/strings/utf_string_conversions.h"
+#include "base/win/scoped_comptr.h"
 #include "base/win/scoped_gdi_object.h"
 #include "base/win/scoped_hdc.h"
 #include "base/win/scoped_select_object.h"
 #include "base/win/win_util.h"
 #include "ui/gfx/canvas.h"
 #include "ui/gfx/font.h"
 #include "ui/gfx/font_render_params.h"
 #include "ui/gfx/win/scoped_set_map_mode.h"
 
 namespace {
@@ skipping 46 matching lines @@
 
 // static
 PlatformFontWin::HFontRef* PlatformFontWin::base_font_ref_;
 
 // static
 PlatformFontWin::AdjustFontCallback
     PlatformFontWin::adjust_font_callback = NULL;
 PlatformFontWin::GetMinimumFontSizeCallback
     PlatformFontWin::get_minimum_font_size_callback = NULL;
 
+IDWriteFactory* PlatformFontWin::direct_write_factory_ = NULL;
+
 ////////////////////////////////////////////////////////////////////////////////
 // PlatformFontWin, public
 
 PlatformFontWin::PlatformFontWin() : font_ref_(GetBaseFontRef()) {
 }
 
 PlatformFontWin::PlatformFontWin(NativeFont native_font) {
   InitWithCopyOfHFONT(native_font);
 }
 
@@ skipping 146 matching lines @@
     base_font_ref_ = PlatformFontWin::CreateHFontRef(font);
     // base_font_ref_ is global, up the ref count so it's never deleted.
     base_font_ref_->AddRef();
   }
   return base_font_ref_;
 }
 
 PlatformFontWin::HFontRef* PlatformFontWin::CreateHFontRef(HFONT font) {
   TEXTMETRIC font_metrics;
 
+  if (direct_write_factory_) {
+    base::win::ScopedGDIObject<HFONT> gdi_font(font);
+    font = ConvertGDIFontToDirectWriteFont(gdi_font);
+  }
+
   {
     base::win::ScopedGetDC screen_dc(NULL);
     gfx::ScopedSetMapMode mode(screen_dc, MM_TEXT);
     GetTextMetricsForFont(screen_dc, font, &font_metrics);
   }
 
   return CreateHFontRef(font, font_metrics);
 }
 
 PlatformFontWin::HFontRef* PlatformFontWin::CreateHFontRef(
@@ skipping 42 matching lines @@
     GetTextMetricsForFont(screen_dc, font, &font_metrics);
     if (font_metrics.tmHeight > best_font_metrics.tmHeight)
       break;
     best_font.Set(font.release());
     best_font_metrics = font_metrics;
   } while (true);
 
   return Font(new PlatformFontWin(CreateHFontRef(best_font.release())));
 }
 
+// static
+HFONT PlatformFontWin::ConvertGDIFontToDirectWriteFont(HFONT gdi_font) {

[scottmg, 2014/10/29 21:33:32]

seems a bit weird to me that that round trip actually does what want, but if it
works...

[ananta, 2014/10/29 21:56:18]

Yes. I had a hunch though :)

+  // This function uses  the DirectWrite Gdi interop interfaces to convert the
+  // gdi font passed in to a HFONT which is compatible with DirectWrite font
+  // metrics which could be different from GDI font metrics. This ensures that
+  // widgets like labels which use font metrics to calculate bounds have the
+  // same calculations as skia which uses DirectWrite.
+  DCHECK(direct_write_factory_);
+  base::win::ScopedComPtr<IDWriteGdiInterop> gdi_interop;
+  HRESULT hr = direct_write_factory_->GetGdiInterop(gdi_interop.Receive());
+  if (FAILED(hr)) {
+    CHECK(false);

[scottmg, 2014/10/29 21:33:32]

check(false); return NULL; doesn't make any sense, it can't get past the check
(+ 2 more below)

[ananta, 2014/10/29 21:56:18]

Added the returns for semantics only.

+    return NULL;
+  }
+
+  base::win::ScopedGetDC screen_dc(NULL);
+  gfx::ScopedSetMapMode mode(screen_dc, MM_TEXT);
+
+  base::win::ScopedSelectObject scoped_font(screen_dc, gdi_font);
+
+  base::win::ScopedComPtr<IDWriteFontFace> font_face_gdi;
+  hr = gdi_interop->CreateFontFaceFromHdc(screen_dc, font_face_gdi.Receive());
+  if (FAILED(hr)) {
+    CHECK(false);
+    return NULL;
+  }
+
+  LOGFONT dwrite_to_gdi_log_font = {0};
+  hr = gdi_interop->ConvertFontFaceToLOGFONT(font_face_gdi,
+                                             &dwrite_to_gdi_log_font);
+  if (FAILED(hr)) {
+    CHECK(false);
+    return NULL;
+  }
+  return CreateFontIndirect(&dwrite_to_gdi_log_font);
+}
+
 PlatformFontWin::PlatformFontWin(HFontRef* hfont_ref) : font_ref_(hfont_ref) {
 }
 
 ////////////////////////////////////////////////////////////////////////////////
 // PlatformFontWin::HFontRef:
 
 PlatformFontWin::HFontRef::HFontRef(HFONT hfont,
                                     int font_size,
                                     int height,
                                     int baseline,
@@ skipping 55 matching lines @@
   return new PlatformFontWin(native_font);
 }
 
 // static
 PlatformFont* PlatformFont::CreateFromNameAndSize(const std::string& font_name,
                                                   int font_size) {
   return new PlatformFontWin(font_name, font_size);
 }
 
 }  // namespace gfx