1 /* 2 * Copyright (C) 2010 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #ifndef SkPDFPage_DEFINED 18 #define SkPDFPage_DEFINED 19 20 #include "SkPDFTypes.h" 21 #include "SkPDFStream.h" 22 #include "SkRefCnt.h" 23 #include "SkTDArray.h" 24 25 class SkPDFCatalog; 26 class SkPDFDevice; 27 class SkWStream; 28 29 /** \class SkPDFPage 30 31 A SkPDFPage contains meta information about a page, is used in the page 32 tree and points to the content of the page. 33 */ 34 class SkPDFPage : public SkPDFDict { 35 public: 36 /** Create a PDF page with the passed PDF device. The device need not 37 * have content on it yet. 38 * @param content The page content. 39 */ 40 explicit SkPDFPage(const SkRefPtr<SkPDFDevice>& content); 41 ~SkPDFPage(); 42 43 /** Before a page and its contents can be sized and emitted, it must 44 * be finalized. No changes to the PDFDevice will be honored after 45 * finalizePage has been called. This function adds the page content 46 * to the passed catalog, so it must be called for each document 47 * that the page is part of. 48 * @param catalog The catalog to add page content objects to. 49 * @param firstPage Indicate if this is the first page of a document. 50 * @param resourceObjects The resource objects used on the page are added 51 * to this array. This gives the caller a chance 52 * to deduplicate resources across pages. 53 */ 54 void finalizePage(SkPDFCatalog* catalog, bool firstPage, 55 SkTDArray<SkPDFObject*>* resourceObjects); 56 57 /** Determine the size of the page content and store to the catalog 58 * the offsets of all nonresource-indirect objects that make up the page 59 * content. This must be called before emitPage(), but after finalizePage. 60 * @param catalog The catalog to add the object offsets to. 61 * @param fileOffset The file offset where the page content will be 62 * emitted. 63 */ 64 off_t getPageSize(SkPDFCatalog* catalog, off_t fileOffset); 65 66 /** Output the page content to the passed stream. 67 * @param stream The writable output stream to send the content to. 68 * @param catalog The active object catalog. 69 */ 70 void emitPage(SkWStream* stream, SkPDFCatalog* catalog); 71 72 /** Generate a page tree for the passed vector of pages. New objects are 73 * added to the catalog. The pageTree vector is populated with all of 74 * the 'Pages' dictionaries as well as the 'Page' objects. Page trees 75 * have both parent and children links, creating reference cycles, so 76 * it must be torn down explicitly. The first page is not added to 77 * the pageTree dictionary array so the caller can handle it specially. 78 * @param pages The ordered vector of page objects. 79 * @param catalog The catalog to add new objects into. 80 * @param pageTree An output vector with all of the internal and leaf 81 * nodes of the pageTree. 82 * @param rootNode An output parameter set to the root node. 83 */ 84 static void generatePageTree(const SkTDArray<SkPDFPage*>& pages, 85 SkPDFCatalog* catalog, 86 SkTDArray<SkPDFDict*>* pageTree, 87 SkPDFDict** rootNode); 88 89 /** Get the fonts used on this page. 90 */ 91 SK_API const SkTDArray<SkPDFFont*>& getFontResources() const; 92 93 private: 94 // Multiple pages may reference the content. 95 SkRefPtr<SkPDFDevice> fDevice; 96 97 // Once the content is finalized, put it into a stream for output. 98 SkRefPtr<SkPDFStream> fContentStream; 99 }; 100 101 #endif 102
