Added support for vector printing of Pepper v1 plugins on the Mac.

BUG=None.
TEST=Test printing from Chrome PDF plugin on the Mac.

Review URL: http://codereview.chromium.org/2808029

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@51008 0039d316-1c4b-4281-b951-d872f2087c98

4 files changed, 57 insertions, 10 deletions

diff --git a/printing/image.cc b/printing/image.cc
index dbee79d..d12d3d60 100644
--- a/printing/image.cc
+++ b/printing/image.cc
@@ -250,7 +250,8 @@ bool Image::LoadMetafile(const NativeMetafile& metafile) {
                               kCGImageAlphaPremultipliedLast));
     DCHECK(bitmap_context.get());
     metafile.RenderPage(page_number, bitmap_context,
-                        CGRectMake(0, 0, size_.width(), size_.height()));
+                        CGRectMake(0, 0, size_.width(), size_.height()),
+                        true, false, false, false);
   }
 #else
   NOTIMPLEMENTED();
diff --git a/printing/pdf_metafile_mac.cc b/printing/pdf_metafile_mac.cc
index c4aa4f0..1726ba0 100644
--- a/printing/pdf_metafile_mac.cc
+++ b/printing/pdf_metafile_mac.cc
@@ -105,7 +105,10 @@ void PdfMetafile::Close() {
 }
 
 bool PdfMetafile::RenderPage(unsigned int page_number, CGContextRef context,
-                             const CGRect rect) const {
+                             const CGRect rect, bool shrink_to_fit,
+                             bool stretch_to_fit,
+                             bool center_horizontally,
+                             bool center_vertically) const {
   CGPDFDocumentRef pdf_doc = GetPDFDocument();
   if (!pdf_doc) {
     LOG(ERROR) << "Unable to create PDF document from data";
@@ -113,14 +116,43 @@ bool PdfMetafile::RenderPage(unsigned int page_number, CGContextRef context,
   }
   CGPDFPageRef pdf_page = CGPDFDocumentGetPage(pdf_doc, page_number);
   CGRect source_rect = CGPDFPageGetBoxRect(pdf_page, kCGPDFMediaBox);
+  float scaling_factor = 1.0;
+  // See if we need to scale the output.
+  bool scaling_needed =
+      (shrink_to_fit && ((source_rect.size.width > rect.size.width) ||
+                         (source_rect.size.height > rect.size.height))) ||
+      (stretch_to_fit && (source_rect.size.width < rect.size.width) &&
+          (source_rect.size.height < rect.size.height));
+  if (scaling_needed) {
+    float x_scaling_factor = rect.size.width / source_rect.size.width;
+    float y_scaling_factor = rect.size.height / source_rect.size.height;
+    if (x_scaling_factor > y_scaling_factor) {
+      scaling_factor = y_scaling_factor;
+    } else {
+      scaling_factor = x_scaling_factor;
+    }
+  }
+  // Some PDFs have a non-zero origin. Need to take that into account.
+  float x_offset = rect.origin.x - (source_rect.origin.x * scaling_factor);
+  float y_offset = rect.origin.y - (source_rect.origin.y * scaling_factor);
 
+  if (center_vertically) {
+    x_offset += (rect.size.width -
+                     (source_rect.size.width * scaling_factor))/2;
+  }
+  if (center_horizontally) {
+    y_offset += (rect.size.height -
+                     (source_rect.size.height * scaling_factor))/2;
+  } else {
+    // Since 0 y begins at the bottom, we need to adjust so the output appears
+    // nearer the top if we are not centering horizontally.
+    y_offset += rect.size.height - (source_rect.size.height * scaling_factor);
+  }
   CGContextSaveGState(context);
-  CGContextTranslateCTM(context, rect.origin.x, rect.origin.y);
-  CGContextScaleCTM(context, rect.size.width / source_rect.size.width,
-                    rect.size.height / source_rect.size.height);
+  CGContextTranslateCTM(context, x_offset, y_offset);
+  CGContextScaleCTM(context, scaling_factor, scaling_factor);
   CGContextDrawPDFPage(context, pdf_page);
   CGContextRestoreGState(context);
-
   return true;
 }
 
diff --git a/printing/pdf_metafile_mac.h b/printing/pdf_metafile_mac.h
index 6e50913..264e970 100644
--- a/printing/pdf_metafile_mac.h
+++ b/printing/pdf_metafile_mac.h
@@ -51,10 +51,23 @@ class PdfMetafile {
   void Close();
 
   // Renders the given page into |rect| in the given context.
-  // Pages use a 1-based index.
+  // Pages use a 1-based index. The rendering uses the following arguments
+  // to determine scaling and translation factors.
+  // |shrink_to_fit| specifies whether the output should be shrunk to fit the
+  // supplied |rect| if the page size is larger than |rect| in any dimension.
+  // If this is false, parts of the PDF page that lie outside the bounds will be
+  // clipped.
+  // |stretch_to_fit| specifies whether the output should be stretched to fit
+  // the supplied bounds if the page size is smaller than |rect| in all
+  // dimensions.
+  // |center_horizontally| specifies whether the final image (after any scaling
+  // is done) should be centered horizontally within the given |rect|.
+  // |center_vertically| specifies whether the final image (after any scaling
+  // is done) should be centered vertically within the given |rect|.
+  // Note that all scaling preserves the original aspect ratio of the page.
   bool RenderPage(unsigned int page_number, CGContextRef context,
-                  const CGRect rect) const;
-
+                  const CGRect rect, bool shrink_to_fit, bool stretch_to_fit,
+                  bool center_horizontally, bool center_vertically) const;
   unsigned int GetPageCount() const;
 
   // Returns the bounds of the given page.
diff --git a/printing/printed_document_mac.cc b/printing/printed_document_mac.cc
index 422dacf..a3ea8c4 100644
--- a/printing/printed_document_mac.cc
+++ b/printing/printed_document_mac.cc
@@ -31,7 +31,8 @@ void PrintedDocument::RenderPrintedPage(
   const printing::NativeMetafile* metafile = page.native_metafile();
   // Each NativeMetafile is a one-page PDF, and pages use 1-based indexing.
   const int page_number = 1;
-  metafile->RenderPage(page_number, context, target_rect);
+  metafile->RenderPage(page_number, context, target_rect, true, false, false,
+                       false);
 
   // TODO(stuartmorgan): Print the header and footer.
 }