When printing a page containing alpha blending on a printer which doesn't support alpha blending, post-process the

metafile to replace the AlphaBlend calls with BitBlts from a software-composited rendering of the page so far.

BUG=7434
TEST=see bug

Review URL: http://codereview.chromium.org/5362002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@71177 0039d316-1c4b-4281-b951-d872f2087c98

4 files changed, 15 insertions, 1 deletions

diff --git a/printing/emf_win.cc b/printing/emf_win.cc
index 9629bb2..5de962b 100644
--- a/printing/emf_win.cc
+++ b/printing/emf_win.cc
@@ -396,6 +396,8 @@ bool Emf::Record::SafePlayback(const XFORM* base_matrix) const {
         } else {
           res = Play();
         }
+      } else {
+        res = true;
       }
       break;
     }
diff --git a/printing/print_settings.cc b/printing/print_settings.cc
index cf8c50a..3f0f842 100644
--- a/printing/print_settings.cc
+++ b/printing/print_settings.cc
@@ -19,7 +19,8 @@ PrintSettings::PrintSettings()
       selection_only(false),
       use_overlays(true),
       dpi_(0),
-      landscape_(false) {
+      landscape_(false),
+      supports_alpha_blend_(true) {
 }
 
 PrintSettings::~PrintSettings() {
@@ -36,6 +37,7 @@ void PrintSettings::Clear() {
   page_setup_device_units_.Clear();
   dpi_ = 0;
   landscape_ = false;
+  supports_alpha_blend_ = true;
 }
 
 void PrintSettings::SetPrinterPrintableArea(
diff --git a/printing/print_settings.h b/printing/print_settings.h
index bc9cbaf..298fcd2 100644
--- a/printing/print_settings.h
+++ b/printing/print_settings.h
@@ -42,6 +42,10 @@ class PrintSettings {
   const std::wstring& device_name() const { return device_name_; }
   void set_dpi(int dpi) { dpi_ = dpi; }
   int dpi() const { return dpi_; }
+  void set_supports_alpha_blend(bool supports_alpha_blend) {
+    supports_alpha_blend_ = supports_alpha_blend;
+  }
+  bool supports_alpha_blend() const { return supports_alpha_blend_; }
   const PageSetup& page_setup_device_units() const {
     return page_setup_device_units_;
   }
@@ -108,6 +112,9 @@ class PrintSettings {
 
   // Is the orientation landscape or portrait.
   bool landscape_;
+
+  // True if this printer supports AlphaBlend.
+  bool supports_alpha_blend_;
 };
 
 }  // namespace printing
diff --git a/printing/print_settings_initializer_win.cc b/printing/print_settings_initializer_win.cc
index f840f4d..065a8db 100644
--- a/printing/print_settings_initializer_win.cc
+++ b/printing/print_settings_initializer_win.cc
@@ -29,6 +29,9 @@ void PrintSettingsInitializerWin::InitPrintSettings(
 
   int dpi = GetDeviceCaps(hdc, LOGPIXELSX);
   print_settings->set_dpi(dpi);
+  const int kAlphaCaps = SB_CONST_ALPHA | SB_PIXEL_ALPHA;
+  print_settings->set_supports_alpha_blend(
+    (GetDeviceCaps(hdc, SHADEBLENDCAPS) & kAlphaCaps) == kAlphaCaps);
   // No printer device is known to advertise different dpi in X and Y axis; even
   // the fax device using the 200x100 dpi setting. It's ought to break so many
   // applications that it's not even needed to care about. WebKit doesn't