pdfviewer: add doPage function, cet stream from Contents

experimental/PdfViewer/SkPdfRenderer.cpp

 /*
  * Copyright 2013 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkCanvas.h"
 #include "SkDevice.h"
 #include "SkForceLinking.h"
@@ skipping 766 matching lines @@
             return doXObject_Image(pdfContext, canvas, (SkPdfImageDictionary*)obj);
         case kType1FormDictionary_SkPdfObjectType:
             return doXObject_Form(pdfContext, canvas, (SkPdfType1FormDictionary*)obj);
         //case kObjectDictionaryXObjectPS_SkPdfObjectType:
             //return doXObject_PS(skxobj.asPS());
         default:
             return kIgnoreError_PdfResult;
     }
 }
 
+static PdfResult doPage(PdfContext* pdfContext, SkCanvas* canvas, SkPdfPageObjectDictionary* skobj) {
+    if (!skobj) {
+        return kIgnoreError_PdfResult;
+    }
+
+    if (!skobj->isContentsAStream(pdfContext->fPdfDoc)) {
+        return kNYI_PdfResult;
+    }
+
+    SkPdfStream* stream = skobj->getContentsAsStream(pdfContext->fPdfDoc);
+
+    if (!stream) {
+        return kIgnoreError_PdfResult;
+    }
+
+    if (CheckRecursiveRendering::IsInRendering(skobj)) {
+        // Oops, corrupt PDF!
+        return kIgnoreError_PdfResult;
+    }
+    CheckRecursiveRendering checkRecursion(skobj);
+
+
+    PdfOp_q(pdfContext, canvas, NULL);
+
+    canvas->save();
+
+    if (skobj->Resources(pdfContext->fPdfDoc)) {
+        pdfContext->fGraphicsState.fResources = skobj->Resources(pdfContext->fPdfDoc);
+    }
+
+    // TODO(edisonn): refactor common path with doXObject()
+    // This is a group?
+    if (skobj->has_Group()) {
+        //TransparencyGroupDictionary* ...
+    }
+
+    SkPdfNativeTokenizer* tokenizer =
+            pdfContext->fPdfDoc->tokenizerOfStream(stream, pdfContext->fTmpPageAllocator);
+    if (tokenizer != NULL) {
+        PdfMainLooper looper(NULL, tokenizer, pdfContext, canvas);
+        looper.loop();
+        delete tokenizer;
+    }
+
+    // TODO(edisonn): should we restore the variable stack at the same state?
+    // There could be operands left, that could be consumed by a parent tokenizer when we pop.
+    canvas->restore();
+    PdfOp_Q(pdfContext, canvas, NULL);
+    return kPartial_PdfResult;
+}
+
 PdfResult PdfOp_q(PdfContext* pdfContext, SkCanvas* canvas, PdfTokenLooper** looper) {
     pdfContext->fStateStack.push(pdfContext->fGraphicsState);
     canvas->save();
     return kOK_PdfResult;
 }
 
 PdfResult PdfOp_Q(PdfContext* pdfContext, SkCanvas* canvas, PdfTokenLooper** looper) {
     pdfContext->fGraphicsState = pdfContext->fStateStack.top();
     pdfContext->fStateStack.pop();
     canvas->restore();
@@ skipping 1381 matching lines @@
     if (!fPdfDoc) {
         return false;
     }
 
     if (page < 0 || page >= pages()) {
         return false;
     }
 
     PdfContext pdfContext(fPdfDoc);
 
-    SkPdfNativeTokenizer* tokenizer = fPdfDoc->tokenizerOfPage(page, pdfContext.fTmpPageAllocator);
-    if (!tokenizer) {
-        // TODO(edisonn): report/warning/debug
-        return false;
-    }
-
     pdfContext.fOriginalMatrix = SkMatrix::I();
     pdfContext.fGraphicsState.fResources = fPdfDoc->pageResources(page);
 
     gPdfContext = &pdfContext;
 
     // TODO(edisonn): get matrix stuff right.
     SkScalar z = SkIntToScalar(0);
     SkScalar w = dst.width();
     SkScalar h = dst.height();
 
@@ skipping 29 matching lines @@
     pdfContext.fGraphicsState.fCTM = pdfContext.fOriginalMatrix;
     pdfContext.fGraphicsState.fMatrixTm = pdfContext.fGraphicsState.fCTM;
     pdfContext.fGraphicsState.fMatrixTlm = pdfContext.fGraphicsState.fCTM;
 
 #ifndef PDF_DEBUG_NO_PAGE_CLIPING
     canvas->clipRect(dst, SkRegion::kIntersect_Op, true);
 #endif
 
     canvas->setMatrix(pdfContext.fOriginalMatrix);
 
-// erase with red before?
+    doPage(&pdfContext, canvas, fPdfDoc->page(page));
+
+          // TODO(edisonn:) erase with white before draw?
 //        SkPaint paint;
-//        paint.setColor(SK_ColorRED);
+//        paint.setColor(SK_ColorWHITE);
 //        canvas->drawRect(rect, paint);
 
-    PdfMainLooper looper(NULL, tokenizer, &pdfContext, canvas);
-    looper.loop();
-
-    delete tokenizer;
 
     canvas->flush();
     return true;
 }
 
 bool SkPdfRenderer::load(const SkString inputFileName) {
     unload();
 
     // TODO(edisonn): create static function that could return NULL if there are errors
     fPdfDoc = new SkNativeParsedPDF(inputFileName.c_str());
@@ skipping 56 matching lines @@
 
     rect = SkRect::MakeWH(width, height);
 
     setup_bitmap(output, (int)SkScalarToDouble(width), (int)SkScalarToDouble(height));
 
     SkAutoTUnref<SkDevice> device(SkNEW_ARGS(SkDevice, (*output)));
     SkCanvas canvas(device);
 
     return renderer.renderPage(page, &canvas, rect);
 }