add ability to specify the DPI at which to render the page

experimental/PdfViewer/pdf_viewer_main.cpp

 #include "SkCanvas.h"
 #include "SkCommandLineFlags.h"
 #include "SkDevice.h"
 #include "SkGraphics.h"
 #include "SkImageDecoder.h"
 #include "SkImageEncoder.h"
 #include "SkOSFile.h"
 #include "SkPicture.h"
 #include "SkStream.h"
 #include "SkTypeface.h"
@@ skipping 83 matching lines @@
  * @param outputDir Output dir.
  * @param inputFilename The skp file that was read.
  * @param renderer The object responsible to write the pdf file.
  * @param page -1 means there is only one page (0), and render in a file without page extension
  */
 
 extern "C" SkBitmap* gDumpBitmap;
 extern "C" SkCanvas* gDumpCanvas;
 
 static bool render_page(const SkString& outputDir,
-                         const SkString& inputFilename,
-                         const SkPdfRenderer& renderer,
-                         int page) {
+                        const SkString& inputFilename,
+                        const SkPdfRenderer& renderer,
+                        int page) {
     SkRect rect = renderer.MediaBox(page < 0 ? 0 :page);
 
     SkBitmap bitmap;
+    SkScalar width = SkScalarMul(rect.width(),  SkDoubleToScalar(sqrt(FLAGS_DPI / 72.0)));
+    SkScalar height = SkScalarMul(rect.height(),  SkDoubleToScalar(sqrt(FLAGS_DPI / 72.0)));
+
+    rect = SkRect::MakeWH(width, height);
+
 #ifdef PDF_DEBUG_3X
-    setup_bitmap(&bitmap, 3 * (int)SkScalarToDouble(rect.width()), 3 * (int)SkScalarToDouble(rect.height()));
+    setup_bitmap(&bitmap, 3 * (int)SkScalarToDouble(width), 3 * (int)SkScalarToDouble(height));
 #else
-    setup_bitmap(&bitmap, (int)SkScalarToDouble(rect.width()), (int)SkScalarToDouble(rect.height()));
+    setup_bitmap(&bitmap, (int)SkScalarToDouble(width), (int)SkScalarToDouble(height));
 #endif
     SkAutoTUnref<SkDevice> device(SkNEW_ARGS(SkDevice, (bitmap)));
     SkCanvas canvas(device);
 
     gDumpBitmap = &bitmap;
 
     gDumpCanvas = &canvas;
-    renderer.renderPage(page < 0 ? 0 : page, &canvas);
+    renderer.renderPage(page < 0 ? 0 : page, &canvas, rect);
 
     SkString outputPath;
     if (!make_output_filepath(&outputPath, outputDir, inputFilename, page)) {
         return false;
     }
     SkImageEncoder::EncodeFile(outputPath.c_str(), bitmap, SkImageEncoder::kPNG_Type, 100);
 
     if (FLAGS_showMemoryUsage) {
         SkDebugf("Memory usage after page %i rendered: %u\n", page < 0 ? 0 : page, (unsigned int)renderer.bytesUsed());
     }
@@ skipping 116 matching lines @@
     }
 
     return 0;
 }
 
 #if !defined SK_BUILD_FOR_IOS
 int main(int argc, char * const argv[]) {
     return tool_main(argc, (char**) argv);
 }
 #endif