DM: add --multiPage option

dm/DMSrcSink.cpp

 /*
  * Copyright 2015 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "DMSrcSink.h"
 #include "SamplePipeControllers.h"
 #include "SkCommonFlags.h"
 #include "SkCodec.h"
 #include "SkData.h"
 #include "SkDocument.h"
 #include "SkError.h"
 #include "SkImageGenerator.h"
 #include "SkMultiPictureDraw.h"
 #include "SkNullCanvas.h"
 #include "SkOSFile.h"
 #include "SkPictureData.h"
 #include "SkPictureRecorder.h"
 #include "SkRandom.h"
 #include "SkScanlineDecoder.h"
 #include "SkSVGCanvas.h"
 #include "SkStream.h"
 #include "SkXMLWriter.h"
 
+DEFINE_bool(multiPage, false, "For document-type backends, render the source"
+            " into multiple pages");
+
 static bool lazy_decode_bitmap(const void* src, size_t size, SkBitmap* dst) {
     SkAutoTUnref<SkData> encoded(SkData::NewWithCopy(src, size));
     return encoded && SkInstallDiscardablePixelRef(encoded, dst);
 }
 
 namespace DM {
 
 GMSrc::GMSrc(skiagm::GMRegistry::Factory factory) : fFactory(factory) {}
 
 Error GMSrc::draw(SkCanvas* canvas) const {
@@ skipping 333 matching lines @@
 }
 
 /*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/
 
 static Error draw_skdocument(const Src& src, SkDocument* doc, SkWStream* dst) {
     // Print the given DM:Src to a document, breaking on 8.5x11 pages.
     SkASSERT(doc);
     int width  = src.size().width(),
         height = src.size().height();
 
-    const int kLetterWidth  = 612,  // 8.5 * 72
-              kLetterHeight = 792;  // 11 * 72
-    const SkRect letter = SkRect::MakeWH(SkIntToScalar(kLetterWidth),
-                                         SkIntToScalar(kLetterHeight));
+    if (FLAGS_multiPage) {
+        const int kLetterWidth = 612,  // 8.5 * 72
+                kLetterHeight = 792;   // 11 * 72
+        const SkRect letter = SkRect::MakeWH(SkIntToScalar(kLetterWidth),
+                                             SkIntToScalar(kLetterHeight));
 
-    int xPages = ((width - 1) / kLetterWidth) + 1;
-    int yPages = ((height - 1) / kLetterHeight) + 1;
+        int xPages = ((width - 1) / kLetterWidth) + 1;
+        int yPages = ((height - 1) / kLetterHeight) + 1;
 
-    for (int y = 0; y < yPages; ++y) {
-        for (int x = 0; x < xPages; ++x) {
-            int w = SkTMin(kLetterWidth, width - (x * kLetterWidth));
-            int h = SkTMin(kLetterHeight, height - (y * kLetterHeight));
-            SkCanvas* canvas =
-                    doc->beginPage(SkIntToScalar(w), SkIntToScalar(h));
-            if (!canvas) {
-              return "SkDocument::beginPage(w,h) returned NULL";
+        for (int y = 0; y < yPages; ++y) {
+            for (int x = 0; x < xPages; ++x) {
+                int w = SkTMin(kLetterWidth, width - (x * kLetterWidth));
+                int h = SkTMin(kLetterHeight, height - (y * kLetterHeight));
+                SkCanvas* canvas =
+                        doc->beginPage(SkIntToScalar(w), SkIntToScalar(h));
+                if (!canvas) {
+                    return "SkDocument::beginPage(w,h) returned NULL";
+                }
+                canvas->clipRect(letter);
+                canvas->translate(-letter.width() * x, -letter.height() * y);
+                Error err = src.draw(canvas);
+                if (!err.isEmpty()) {
+                    return err;
+                }
+                doc->endPage();
             }
-            canvas->clipRect(letter);
-            canvas->translate(-letter.width() * x, -letter.height() * y);
-            Error err = src.draw(canvas);
-            if (!err.isEmpty()) {
-                return err;
-            }
-            doc->endPage();
         }
+    } else {
+        SkCanvas* canvas =
+                doc->beginPage(SkIntToScalar(width), SkIntToScalar(height));
+        if (!canvas) {
+            return "SkDocument::beginPage(w,h) returned NULL";
+        }
+        Error err = src.draw(canvas);
+        if (!err.isEmpty()) {
+            return err;
+        }
+        doc->endPage();
     }
-    doc->close();
+    if (!doc->close()) {
+        return "SkDocument::close() returned false";
+    }
     dst->flush();
     return "";
 }
 
 PDFSink::PDFSink() {}
 
 Error PDFSink::draw(const Src& src, SkBitmap*, SkWStream* dst, SkString*) const {
     SkAutoTUnref<SkDocument> doc(SkDocument::CreatePDF(dst));
     if (!doc) {
         return "SkDocument::CreatePDF() returned NULL";
@@ skipping 278 matching lines @@
             canvas->drawPicture(pic);
             return "";
         }
         SkISize size() const override { return fSrc.size(); }
         Name name() const override { sk_throw(); return ""; }  // No one should be calling this.
     } proxy(src);
     return fSink->draw(proxy, bitmap, stream, log);
 }
 
 }  // namespace DM