Add Postscript Printing

chrome/utility/printing_handler.cc

 // Copyright 2014 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 "chrome/utility/printing_handler.h"
 
 #include <stdint.h>
 #include <utility>
 
 #include "base/files/file_util.h"
@@ skipping 71 matching lines @@
     IPC_MESSAGE_UNHANDLED(handled = false)
   IPC_END_MESSAGE_MAP()
   return handled;
 }
 
 #if defined(OS_WIN)
 void PrintingHandler::OnRenderPDFPagesToMetafile(
     IPC::PlatformFileForTransit pdf_transit,
     const PdfRenderSettings& settings) {
   pdf_rendering_settings_ = settings;
+  chrome_pdf::SetPDFPostscriptPrintingLevel(0);  // Not using postscript.
   chrome_pdf::SetPDFUseGDIPrinting(pdf_rendering_settings_.mode ==
                                    PdfRenderSettings::Mode::GDI_TEXT);
+  if (pdf_rendering_settings_.mode ==
+      PdfRenderSettings::Mode::POSTSCRIPT_LEVEL2) {
+    chrome_pdf::SetPDFPostscriptPrintingLevel(2);
+  } else if (pdf_rendering_settings_.mode ==
+             PdfRenderSettings::Mode::POSTSCRIPT_LEVEL3) {
+    chrome_pdf::SetPDFPostscriptPrintingLevel(3);
+  }
   base::File pdf_file = IPC::PlatformFileForTransitToFile(pdf_transit);
   int page_count = LoadPDF(std::move(pdf_file));
   Send(
       new ChromeUtilityHostMsg_RenderPDFPagesToMetafiles_PageCount(page_count));
 }
 
 void PrintingHandler::OnRenderPDFPagesToMetafileGetPage(
     int page_number,
     IPC::PlatformFileForTransit output_file) {
   base::File emf_file = IPC::PlatformFileForTransitToFile(output_file);
   float scale_factor = 1.0f;
-  bool success =
-      RenderPdfPageToMetafile(page_number, std::move(emf_file), &scale_factor);
+  bool success = false;
+  if (pdf_rendering_settings_.mode ==
+          PdfRenderSettings::Mode::POSTSCRIPT_LEVEL2 ||
+      pdf_rendering_settings_.mode ==
+          PdfRenderSettings::Mode::POSTSCRIPT_LEVEL3) {
+    success = RenderPdfPageToPostScript(page_number, std::move(emf_file));

[Nico, 2017/01/31 20:17:42]

add comment why scale factor of 1 is always right in this case

[rbpotter, 2017/02/01 01:09:00]

Done.

+  } else {
+    success = RenderPdfPageToMetafile(page_number, std::move(emf_file),
+                                      &scale_factor);
+  }
+
   Send(new ChromeUtilityHostMsg_RenderPDFPagesToMetafiles_PageDone(
       success, scale_factor));
 }
 
 void PrintingHandler::OnRenderPDFPagesToMetafileStop() {
   ReleaseProcessIfNeeded();
 }
 
-#endif  // OS_WIN
+#endif  // defined(OS_WIN)
 
 #if BUILDFLAG(ENABLE_PRINT_PREVIEW)
 void PrintingHandler::OnRenderPDFPagesToPWGRaster(
     IPC::PlatformFileForTransit pdf_transit,
     const PdfRenderSettings& settings,
     const PwgRasterSettings& bitmap_settings,
     IPC::PlatformFileForTransit bitmap_transit) {
   base::File pdf = IPC::PlatformFileForTransitToFile(pdf_transit);
   base::File bitmap = IPC::PlatformFileForTransitToFile(bitmap_transit);
   if (RenderPDFPagesToPWGRaster(std::move(pdf), settings, bitmap_settings,
                                 std::move(bitmap))) {
     Send(new ChromeUtilityHostMsg_RenderPDFPagesToPWGRaster_Succeeded());
   } else {
     Send(new ChromeUtilityHostMsg_RenderPDFPagesToPWGRaster_Failed());
   }
   ReleaseProcessIfNeeded();
 }
-#endif  // ENABLE_PRINT_PREVIEW
+#endif  // BUILDFLAG(ENABLE_PRINT_PREVIEW)
 
 #if defined(OS_WIN)
 int PrintingHandler::LoadPDF(base::File pdf_file) {
   int64_t length64 = pdf_file.GetLength();
   if (length64 <= 0 || length64 > std::numeric_limits<int>::max())
     return 0;
   int length = static_cast<int>(length64);
 
   pdf_data_.resize(length);
   if (length != pdf_file.Read(0, pdf_data_.data(), pdf_data_.size()))
@@ skipping 34 matching lines @@
           pdf_rendering_settings_.area.y(),
           pdf_rendering_settings_.area.width(),
           pdf_rendering_settings_.area.height(), true, false, true, true,
           pdf_rendering_settings_.autorotate)) {
     return false;
   }
   metafile.FinishPage();
   metafile.FinishDocument();
   return metafile.SaveTo(&output_file);
 }
+
+bool PrintingHandler::RenderPdfPageToPostScript(int page_number,
+                                                base::File output_file) {
+  Emf metafile;
+  metafile.Init();

[Nico, 2017/01/31 20:17:41]

this function looks identical to RenderPdfPageToMetafile except that this
function here looks at pdf_rendering_settings_.offsets while the other one does
some scaling. why the difference? why the duplication?

[rbpotter, 2017/02/01 01:09:00]

I merged these two to eliminate the duplication.
The difference is because the postscript driver does not use the
metafile size since it outputs postscript rather than metafile.
Instead it uses the printable area directly. So we do not need to
scale the HDC to match the metafile, and we need to send the physical
offsets from the printer.

+
+  // The underlying metafile is of type Emf and ignores the arguments passed
+  // to StartPage.
+  metafile.StartPage(gfx::Size(), gfx::Rect(), 1);
+  if (!chrome_pdf::RenderPDFPageToDC(
+          &pdf_data_.front(), pdf_data_.size(), page_number, metafile.context(),
+          pdf_rendering_settings_.dpi, pdf_rendering_settings_.area.x() -
+                                           pdf_rendering_settings_.offsets.x(),
+          pdf_rendering_settings_.area.y() -
+              pdf_rendering_settings_.offsets.y(),
+          pdf_rendering_settings_.area.width(),
+          pdf_rendering_settings_.area.height(), true, false, true, true,
+          pdf_rendering_settings_.autorotate)) {
+    return false;
+  }
+  metafile.FinishPage();
+  metafile.FinishDocument();
+  return metafile.SaveTo(&output_file);
+}
 #endif  // defined(OS_WIN)
 
 #if BUILDFLAG(ENABLE_PRINT_PREVIEW)
 bool PrintingHandler::RenderPDFPagesToPWGRaster(
     base::File pdf_file,
     const PdfRenderSettings& settings,
     const PwgRasterSettings& bitmap_settings,
     base::File bitmap_file) {
   base::File::Info info;
   if (!pdf_file.GetInfo(&info) || info.size <= 0 ||
@@ skipping 104 matching lines @@
   if (print_backend->GetPrinterSemanticCapsAndDefaults(printer_name,
                                                        &printer_info)) {
     Send(new ChromeUtilityHostMsg_GetPrinterSemanticCapsAndDefaults_Succeeded(
         printer_name, printer_info));
   } else {
     Send(new ChromeUtilityHostMsg_GetPrinterSemanticCapsAndDefaults_Failed(
         printer_name));
   }
   ReleaseProcessIfNeeded();
 }
-#endif  // ENABLE_PRINT_PREVIEW
+#endif  // BUILDFLAG(ENABLE_PRINT_PREVIEW)
 
 }  // namespace printing