skia2/include/pdf/SkPDFCatalog.h
2011-03-30 20:14:49 +00:00

103 lines
3.3 KiB
C++

/*
* Copyright (C) 2010 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef SkPDFCatalog_DEFINED
#define SkPDFCatalog_DEFINED
#include <sys/types.h>
#include "SkPDFTypes.h"
#include "SkRefCnt.h"
#include "SkTDArray.h"
/** \class SkPDFCatalog
The PDF catalog manages object numbers and file offsets. It is used
to create the PDF cross reference table.
*/
class SK_API SkPDFCatalog {
public:
/** Create a PDF catalog.
*/
SkPDFCatalog();
~SkPDFCatalog();
/** Add the passed object to the catalog. Refs obj.
* @param obj The object to add.
* @param onFirstPage Is the object on the first page.
* @return The obj argument is returned.
*/
SkPDFObject* addObject(SkPDFObject* obj, bool onFirstPage);
/** Inform the catalog of the object's position in the final stream.
* The object should already have been added to the catalog. Returns
* the object's size.
* @param obj The object to add.
* @param offset The byte offset in the output stream of this object.
*/
size_t setFileOffset(SkPDFObject* obj, size_t offset);
/** Output the object number for the passed object.
* @param obj The object of interest.
* @param stream The writable output stream to send the output to.
*/
void emitObjectNumber(SkWStream* stream, SkPDFObject* obj);
/** Return the number of bytes that would be emitted for the passed
* object's object number.
* @param obj The object of interest
*/
size_t getObjectNumberSize(SkPDFObject* obj);
/** Output the cross reference table for objects in the catalog.
* Returns the total number of objects.
* @param stream The writable output stream to send the output to.
* @param firstPage If true, include first page objects only, otherwise
* include all objects not on the first page.
*/
int32_t emitXrefTable(SkWStream* stream, bool firstPage);
private:
struct Rec {
Rec(SkPDFObject* object, bool onFirstPage)
: fObject(object),
fFileOffset(0),
fObjNumAssigned(false),
fOnFirstPage(onFirstPage) {
}
SkPDFObject* fObject;
off_t fFileOffset;
bool fObjNumAssigned;
bool fOnFirstPage;
};
// TODO(vandebo) Make this a hash if it's a performance problem.
SkTDArray<struct Rec> fCatalog;
// Number of objects on the first page.
uint32_t fFirstPageCount;
// Next object number to assign (on page > 1).
uint32_t fNextObjNum;
// Next object number to assign on the first page.
uint32_t fNextFirstPageObjNum;
int findObjectIndex(SkPDFObject* obj) const;
int assignObjNum(SkPDFObject* obj);
};
#endif