[PDF] Add a concept of a substitute object to the SkPDFCatalog class.
Code by Arthur Hsu, original code review: http://codereview.appspot.com/4650060/
Review URL: http://codereview.appspot.com/4639102
git-svn-id: http://skia.googlecode.com/svn/trunk@1812 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/include/pdf/SkPDFCatalog.h b/include/pdf/SkPDFCatalog.h
index e02ffa1..794bbb1 100644
--- a/include/pdf/SkPDFCatalog.h
+++ b/include/pdf/SkPDFCatalog.h
@@ -70,6 +70,26 @@
*/
int32_t emitXrefTable(SkWStream* stream, bool firstPage);
+ /** Set substitute object for the passed object.
+ */
+ void setSubstitute(SkPDFObject* original, SkPDFObject* substitute);
+
+ /** Find and return any substitute object set for the passed object. If
+ * there is none, return the passed object.
+ */
+ SkPDFObject* getSubstituteObject(SkPDFObject* object);
+
+ /** Set file offsets for the resources of substitute objects.
+ * @param fileOffset Accumulated offset of current document.
+ * @param firstPage Indicate whether this is for the first page only.
+ * @return Accumulated offset of resources of substitute objects.
+ */
+ off_t setSubstituteResourcesOffsets(off_t fileOffset, bool firstPage);
+
+ /** Emit the resources of substitute objects.
+ */
+ void emitSubstituteResources(SkWStream* stream, bool firstPage);
+
private:
struct Rec {
Rec(SkPDFObject* object, bool onFirstPage)
@@ -84,9 +104,22 @@
bool fOnFirstPage;
};
+ struct SubstituteMapping {
+ SubstituteMapping(SkPDFObject* original, SkPDFObject* substitute)
+ : fOriginal(original), fSubstitute(substitute) {
+ }
+ SkPDFObject* fOriginal;
+ SkPDFObject* fSubstitute;
+ };
+
// TODO(vandebo) Make this a hash if it's a performance problem.
SkTDArray<struct Rec> fCatalog;
+ // TODO(arthurhsu) Make this a hash if it's a performance problem.
+ SkTDArray<SubstituteMapping> fSubstituteMap;
+ SkTDArray<SkPDFObject*> fSubstituteResourcesFirstPage;
+ SkTDArray<SkPDFObject*> fSubstituteResourcesRemaining;
+
// Number of objects on the first page.
uint32_t fFirstPageCount;
// Next object number to assign (on page > 1).
@@ -97,6 +130,8 @@
int findObjectIndex(SkPDFObject* obj) const;
int assignObjNum(SkPDFObject* obj);
+
+ SkTDArray<SkPDFObject*>* getSubstituteList(bool firstPage);
};
#endif
diff --git a/include/pdf/SkPDFTypes.h b/include/pdf/SkPDFTypes.h
index 6b5146a..a115802 100644
--- a/include/pdf/SkPDFTypes.h
+++ b/include/pdf/SkPDFTypes.h
@@ -39,15 +39,6 @@
SkPDFObject();
virtual ~SkPDFObject();
- /** Subclasses must implement this method to print the object to the
- * PDF file.
- * @param catalog The object catalog to use.
- * @param indirect If true, output an object identifier with the object.
- * @param stream The writable output stream to send the output to.
- */
- virtual void emitObject(SkWStream* stream, SkPDFCatalog* catalog,
- bool indirect) = 0;
-
/** Return the size (number of bytes) of this object in the final output
* file. Compound objects or objects that are computationally intensive
* to output should override this method.
@@ -65,6 +56,12 @@
*/
virtual void getResources(SkTDArray<SkPDFObject*>* resourceList);
+ /** Emit this object unless the catalog has a substitute object, in which
+ * case emit that.
+ * @see emitObject
+ */
+ void emit(SkWStream* stream, SkPDFCatalog* catalog, bool indirect);
+
/** Helper function to output an indirect object.
* @param catalog The object catalog to use.
* @param stream The writable output stream to send the output to.
@@ -75,6 +72,16 @@
* @param catalog The object catalog to use.
*/
size_t getIndirectOutputSize(SkPDFCatalog* catalog);
+
+protected:
+ /** Subclasses must implement this method to print the object to the
+ * PDF file.
+ * @param catalog The object catalog to use.
+ * @param indirect If true, output an object identifier with the object.
+ * @param stream The writable output stream to send the output to.
+ */
+ virtual void emitObject(SkWStream* stream, SkPDFCatalog* catalog,
+ bool indirect) = 0;
};
/** \class SkPDFObjRef
diff --git a/src/pdf/SkPDFCatalog.cpp b/src/pdf/SkPDFCatalog.cpp
index afa9d9a..5e9d018 100644
--- a/src/pdf/SkPDFCatalog.cpp
+++ b/src/pdf/SkPDFCatalog.cpp
@@ -25,10 +25,15 @@
fNextFirstPageObjNum(0) {
}
-SkPDFCatalog::~SkPDFCatalog() {}
+SkPDFCatalog::~SkPDFCatalog() {
+ fSubstituteResourcesRemaining.safeUnrefAll();
+ fSubstituteResourcesFirstPage.safeUnrefAll();
+}
SkPDFObject* SkPDFCatalog::addObject(SkPDFObject* obj, bool onFirstPage) {
- SkASSERT(findObjectIndex(obj) == -1);
+ if (findObjectIndex(obj) != -1) { // object already added
+ return obj;
+ }
SkASSERT(fNextFirstPageObjNum == 0);
if (onFirstPage)
fFirstPageCount++;
@@ -63,6 +68,12 @@
if (fCatalog[i].fObject == obj)
return i;
}
+ // If it's not in the main array, check if it's a substitute object.
+ for (int i = 0; i < fSubstituteMap.count(); ++i) {
+ if (fSubstituteMap[i].fSubstitute == obj) {
+ return findObjectIndex(fSubstituteMap[i].fOriginal);
+ }
+ }
return -1;
}
@@ -126,3 +137,73 @@
return fCatalog.count() + 1;
}
+
+void SkPDFCatalog::setSubstitute(SkPDFObject* original,
+ SkPDFObject* substitute) {
+#if defined(SK_DEBUG)
+ // Sanity check: is the original already in substitute list?
+ for (int i = 0; i < fSubstituteMap.count(); ++i) {
+ if (original == fSubstituteMap[i].fSubstitute ||
+ original == fSubstituteMap[i].fOriginal) {
+ SkASSERT(false);
+ return;
+ }
+ }
+#endif
+ // Check if the original is on first page.
+ bool onFirstPage = false;
+ for (int i = 0; i < fCatalog.count(); ++i) {
+ if (fCatalog[i].fObject == original) {
+ onFirstPage = fCatalog[i].fOnFirstPage;
+ break;
+ }
+#if defined(SK_DEBUG)
+ if (i == fCatalog.count() - 1) {
+ SkASSERT(false); // original not in catalog
+ return;
+ }
+#endif
+ }
+
+ SubstituteMapping newMapping(original, substitute);
+ fSubstituteMap.append(1, &newMapping);
+
+ // Add resource objects of substitute object to catalog.
+ SkTDArray<SkPDFObject*>* targetList = getSubstituteList(onFirstPage);
+ int existingSize = targetList->count();
+ newMapping.fSubstitute->getResources(targetList);
+ for (int i = existingSize; i < targetList->count(); ++i) {
+ addObject((*targetList)[i], onFirstPage);
+ }
+}
+
+SkPDFObject* SkPDFCatalog::getSubstituteObject(SkPDFObject* object) {
+ for (int i = 0; i < fSubstituteMap.count(); ++i) {
+ if (object == fSubstituteMap[i].fOriginal) {
+ return fSubstituteMap[i].fSubstitute;
+ }
+ }
+ return object;
+}
+
+off_t SkPDFCatalog::setSubstituteResourcesOffsets(off_t fileOffset,
+ bool firstPage) {
+ SkTDArray<SkPDFObject*>* targetList = getSubstituteList(firstPage);
+ off_t offsetSum = fileOffset;
+ for (int i = 0; i < targetList->count(); ++i) {
+ offsetSum += setFileOffset((*targetList)[i], offsetSum);
+ }
+ return offsetSum;
+}
+
+void SkPDFCatalog::emitSubstituteResources(SkWStream *stream, bool firstPage) {
+ SkTDArray<SkPDFObject*>* targetList = getSubstituteList(firstPage);
+ for (int i = 0; i < targetList->count(); ++i) {
+ (*targetList)[i]->emit(stream, this, true);
+ }
+}
+
+SkTDArray<SkPDFObject*>* SkPDFCatalog::getSubstituteList(bool firstPage) {
+ return firstPage ? &fSubstituteResourcesFirstPage :
+ &fSubstituteResourcesRemaining;
+}
\ No newline at end of file
diff --git a/src/pdf/SkPDFDocument.cpp b/src/pdf/SkPDFDocument.cpp
index fce100b..faa9360 100644
--- a/src/pdf/SkPDFDocument.cpp
+++ b/src/pdf/SkPDFDocument.cpp
@@ -78,14 +78,14 @@
fDocCatalog->insert("OutputIntent", intentArray.get());
*/
- bool first_page = true;
+ bool firstPage = true;
for (int i = 0; i < fPages.count(); i++) {
int resourceCount = fPageResources.count();
- fPages[i]->finalizePage(&fCatalog, first_page, &fPageResources);
- addResourcesToCatalog(resourceCount, first_page, &fPageResources,
- &fCatalog);
+ fPages[i]->finalizePage(&fCatalog, firstPage, &fPageResources);
+ addResourcesToCatalog(resourceCount, firstPage, &fPageResources,
+ &fCatalog);
if (i == 0) {
- first_page = false;
+ firstPage = false;
fSecondPageFirstResourceIndex = fPageResources.count();
}
}
@@ -97,6 +97,8 @@
fileOffset += fPages[0]->getPageSize(&fCatalog, fileOffset);
for (int i = 0; i < fSecondPageFirstResourceIndex; i++)
fileOffset += fCatalog.setFileOffset(fPageResources[i], fileOffset);
+ // Add the size of resources of substitute objects used on page 1.
+ fileOffset += fCatalog.setSubstituteResourcesOffsets(fileOffset, true);
if (fPages.count() > 1) {
// TODO(vandebo) For linearized format, save the start of the
// first page xref table and calculate the size.
@@ -113,6 +115,7 @@
i++)
fileOffset += fCatalog.setFileOffset(fPageResources[i], fileOffset);
+ fileOffset += fCatalog.setSubstituteResourcesOffsets(fileOffset, false);
fXRefFileOffset = fileOffset;
}
@@ -121,7 +124,8 @@
fPages[0]->emitObject(stream, &fCatalog, true);
fPages[0]->emitPage(stream, &fCatalog);
for (int i = 0; i < fSecondPageFirstResourceIndex; i++)
- fPageResources[i]->emitObject(stream, &fCatalog, true);
+ fPageResources[i]->emit(stream, &fCatalog, true);
+ fCatalog.emitSubstituteResources(stream, true);
// TODO(vandebo) support linearized format
//if (fPages.size() > 1) {
// // TODO(vandebo) save the file offset for the first page xref table.
@@ -135,8 +139,9 @@
fPages[i]->emitPage(stream, &fCatalog);
for (int i = fSecondPageFirstResourceIndex; i < fPageResources.count(); i++)
- fPageResources[i]->emitObject(stream, &fCatalog, true);
+ fPageResources[i]->emit(stream, &fCatalog, true);
+ fCatalog.emitSubstituteResources(stream, false);
int64_t objCount = fCatalog.emitXrefTable(stream, fPages.count() > 1);
emitFooter(stream, objCount);
return true;
diff --git a/src/pdf/SkPDFTypes.cpp b/src/pdf/SkPDFTypes.cpp
index b9420eb..600145e 100644
--- a/src/pdf/SkPDFTypes.cpp
+++ b/src/pdf/SkPDFTypes.cpp
@@ -27,9 +27,15 @@
SkPDFObject::SkPDFObject() {}
SkPDFObject::~SkPDFObject() {}
+void SkPDFObject::emit(SkWStream* stream, SkPDFCatalog* catalog,
+ bool indirect) {
+ SkPDFObject* realObject = catalog->getSubstituteObject(this);
+ return realObject->emitObject(stream, catalog, indirect);
+}
+
size_t SkPDFObject::getOutputSize(SkPDFCatalog* catalog, bool indirect) {
SkDynamicMemoryWStream buffer;
- emitObject(&buffer, catalog, indirect);
+ emit(&buffer, catalog, indirect);
return buffer.getOffset();
}
@@ -38,7 +44,7 @@
void SkPDFObject::emitIndirectObject(SkWStream* stream, SkPDFCatalog* catalog) {
catalog->emitObjectNumber(stream, this);
stream->writeText(" obj\n");
- emitObject(stream, catalog, false);
+ emit(stream, catalog, false);
stream->writeText("\nendobj\n");
}
@@ -292,7 +298,7 @@
stream->writeText("[");
for (int i = 0; i < fValue.count(); i++) {
- fValue[i]->emitObject(stream, catalog, false);
+ fValue[i]->emit(stream, catalog, false);
if (i + 1 < fValue.count())
stream->writeText(" ");
}
@@ -350,7 +356,7 @@
for (int i = 0; i < fValue.count(); i++) {
fValue[i].key->emitObject(stream, catalog, false);
stream->writeText(" ");
- fValue[i].value->emitObject(stream, catalog, false);
+ fValue[i].value->emit(stream, catalog, false);
stream->writeText("\n");
}
stream->writeText(">>");
diff --git a/tests/PDFPrimitivesTest.cpp b/tests/PDFPrimitivesTest.cpp
index a5feba8..d4d1eea 100644
--- a/tests/PDFPrimitivesTest.cpp
+++ b/tests/PDFPrimitivesTest.cpp
@@ -24,6 +24,24 @@
#include "SkScalar.h"
#include "SkStream.h"
+class SkPDFTestDict : public SkPDFDict {
+public:
+ void getResources(SkTDArray<SkPDFObject*>* resourceList) {
+ resourceList->setReserve(resourceList->count() + fResources.count());
+ for (int i = 0; i < fResources.count(); i++) {
+ resourceList->push(fResources[i]);
+ fResources[i]->ref();
+ }
+ }
+
+ void addResource(SkPDFObject* object) {
+ fResources.append(1, &object);
+ }
+
+private:
+ SkTDArray<SkPDFObject*> fResources;
+};
+
static bool stream_equals(const SkDynamicMemoryWStream& stream, size_t offset,
const void* buffer, size_t len) {
SkAutoDataUnref data(stream.copyToData());
@@ -36,11 +54,12 @@
static void CheckObjectOutput(skiatest::Reporter* reporter, SkPDFObject* obj,
const std::string& representation,
bool indirect) {
- size_t directSize = obj->getOutputSize(NULL, false);
+ SkPDFCatalog catalog;
+ size_t directSize = obj->getOutputSize(&catalog, false);
REPORTER_ASSERT(reporter, directSize == representation.size());
SkDynamicMemoryWStream buffer;
- obj->emitObject(&buffer, NULL, false);
+ obj->emit(&buffer, &catalog, false);
REPORTER_ASSERT(reporter, directSize == buffer.getOffset());
REPORTER_ASSERT(reporter, stream_equals(buffer, 0, representation.c_str(),
directSize));
@@ -52,7 +71,6 @@
static char footer[] = "\nendobj\n";
static size_t footerLen = strlen(footer);
- SkPDFCatalog catalog;
catalog.addObject(obj, false);
size_t indirectSize = obj->getOutputSize(&catalog, true);
@@ -60,7 +78,7 @@
indirectSize == directSize + headerLen + footerLen);
buffer.reset();
- obj->emitObject(&buffer, &catalog, true);
+ obj->emit(&buffer, &catalog, true);
REPORTER_ASSERT(reporter, indirectSize == buffer.getOffset());
REPORTER_ASSERT(reporter, stream_equals(buffer, 0, header, headerLen));
REPORTER_ASSERT(reporter, stream_equals(buffer, headerLen,
@@ -121,6 +139,37 @@
buffer.getOffset()));
}
+static void TestSubstitute(skiatest::Reporter* reporter) {
+ SkRefPtr<SkPDFTestDict> proxy = new SkPDFTestDict();
+ proxy->unref(); // SkRefPtr and new both took a reference.
+ SkRefPtr<SkPDFTestDict> stub = new SkPDFTestDict();
+ stub->unref(); // SkRefPtr and new both took a reference.
+ SkRefPtr<SkPDFInt> int33 = new SkPDFInt(33);
+ int33->unref(); // SkRefPtr and new both took a reference.
+ SkRefPtr<SkPDFDict> stubResource = new SkPDFDict();
+ stubResource->unref(); // SkRefPtr and new both took a reference.
+ SkRefPtr<SkPDFInt> int44 = new SkPDFInt(44);
+ int44->unref(); // SkRefPtr and new both took a reference.
+
+ stub->insert("Value", int33.get());
+ stubResource->insert("InnerValue", int44.get());
+ stub->addResource(stubResource.get());
+
+ SkPDFCatalog catalog;
+ catalog.addObject(proxy.get(), false);
+ catalog.setSubstitute(proxy.get(), stub.get());
+
+ SkDynamicMemoryWStream buffer;
+ proxy->emit(&buffer, &catalog, false);
+ catalog.emitSubstituteResources(&buffer, false);
+
+ char expectedResult[] =
+ "<</Value 33\n>>1 0 obj\n<</InnerValue 44\n>>\nendobj\n";
+ REPORTER_ASSERT(reporter, buffer.getOffset() == strlen(expectedResult));
+ REPORTER_ASSERT(reporter, stream_equals(buffer, 0, expectedResult,
+ buffer.getOffset()));
+}
+
static void TestPDFPrimitives(skiatest::Reporter* reporter) {
SkRefPtr<SkPDFInt> int42 = new SkPDFInt(42);
int42->unref(); // SkRefPtr and new both took a reference.
@@ -212,6 +261,8 @@
TestCatalog(reporter);
TestObjectRef(reporter);
+
+ TestSubstitute(reporter);
}
#include "TestClassDef.h"