1 2 /* 3 * Copyright 2010 The Android Open Source Project 4 * 5 * Use of this source code is governed by a BSD-style license that can be 6 * found in the LICENSE file. 7 */ 8 9 10 #include "SkPDFCatalog.h" 11 #include "SkPDFDevice.h" 12 #include "SkPDFPage.h" 13 #include "SkStream.h" 14 15 SkPDFPage::SkPDFPage(SkPDFDevice* content) 16 : SkPDFDict("Page"), 17 fDevice(content) { 18 SkSafeRef(content); 19 } 20 21 SkPDFPage::~SkPDFPage() {} 22 23 void SkPDFPage::finalizePage(SkPDFCatalog* catalog, bool firstPage, 24 SkTDArray<SkPDFObject*>* resourceObjects) { 25 if (fContentStream.get() == NULL) { 26 insert("Resources", fDevice->getResourceDict()); 27 SkSafeUnref(this->insert("MediaBox", fDevice->copyMediaBox())); 28 if (!SkToBool(catalog->getDocumentFlags() & 29 SkPDFDocument::kNoLinks_Flags)) { 30 SkPDFArray* annots = fDevice->getAnnotations(); 31 if (annots && annots->size() > 0) { 32 insert("Annots", annots); 33 } 34 } 35 36 SkAutoTUnref<SkStream> content(fDevice->content()); 37 fContentStream.reset(new SkPDFStream(content.get())); 38 insert("Contents", new SkPDFObjRef(fContentStream.get()))->unref(); 39 } 40 catalog->addObject(fContentStream.get(), firstPage); 41 fDevice->getResources(resourceObjects, true); 42 } 43 44 off_t SkPDFPage::getPageSize(SkPDFCatalog* catalog, off_t fileOffset) { 45 SkASSERT(fContentStream.get() != NULL); 46 catalog->setFileOffset(fContentStream.get(), fileOffset); 47 return fContentStream->getOutputSize(catalog, true); 48 } 49 50 void SkPDFPage::emitPage(SkWStream* stream, SkPDFCatalog* catalog) { 51 SkASSERT(fContentStream.get() != NULL); 52 fContentStream->emitObject(stream, catalog, true); 53 } 54 55 // static 56 void SkPDFPage::GeneratePageTree(const SkTDArray<SkPDFPage*>& pages, 57 SkPDFCatalog* catalog, 58 SkTDArray<SkPDFDict*>* pageTree, 59 SkPDFDict** rootNode) { 60 // PDF wants a tree describing all the pages in the document. We arbitrary 61 // choose 8 (kNodeSize) as the number of allowed children. The internal 62 // nodes have type "Pages" with an array of children, a parent pointer, and 63 // the number of leaves below the node as "Count." The leaves are passed 64 // into the method, have type "Page" and need a parent pointer. This method 65 // builds the tree bottom up, skipping internal nodes that would have only 66 // one child. 67 static const int kNodeSize = 8; 68 69 SkAutoTUnref<SkPDFName> kidsName(new SkPDFName("Kids")); 70 SkAutoTUnref<SkPDFName> countName(new SkPDFName("Count")); 71 SkAutoTUnref<SkPDFName> parentName(new SkPDFName("Parent")); 72 73 // curNodes takes a reference to its items, which it passes to pageTree. 74 SkTDArray<SkPDFDict*> curNodes; 75 curNodes.setReserve(pages.count()); 76 for (int i = 0; i < pages.count(); i++) { 77 SkSafeRef(pages[i]); 78 curNodes.push(pages[i]); 79 } 80 81 // nextRoundNodes passes its references to nodes on to curNodes. 82 SkTDArray<SkPDFDict*> nextRoundNodes; 83 nextRoundNodes.setReserve((pages.count() + kNodeSize - 1)/kNodeSize); 84 85 int treeCapacity = kNodeSize; 86 do { 87 for (int i = 0; i < curNodes.count(); ) { 88 if (i > 0 && i + 1 == curNodes.count()) { 89 nextRoundNodes.push(curNodes[i]); 90 break; 91 } 92 93 SkPDFDict* newNode = new SkPDFDict("Pages"); 94 SkAutoTUnref<SkPDFObjRef> newNodeRef(new SkPDFObjRef(newNode)); 95 96 SkAutoTUnref<SkPDFArray> kids(new SkPDFArray); 97 kids->reserve(kNodeSize); 98 99 int count = 0; 100 for (; i < curNodes.count() && count < kNodeSize; i++, count++) { 101 curNodes[i]->insert(parentName.get(), newNodeRef.get()); 102 kids->append(new SkPDFObjRef(curNodes[i]))->unref(); 103 104 // TODO(vandebo): put the objects in strict access order. 105 // Probably doesn't matter because they are so small. 106 if (curNodes[i] != pages[0]) { 107 pageTree->push(curNodes[i]); // Transfer reference. 108 catalog->addObject(curNodes[i], false); 109 } else { 110 SkSafeUnref(curNodes[i]); 111 catalog->addObject(curNodes[i], true); 112 } 113 } 114 115 // treeCapacity is the number of leaf nodes possible for the 116 // current set of subtrees being generated. (i.e. 8, 64, 512, ...). 117 // It is hard to count the number of leaf nodes in the current 118 // subtree. However, by construction, we know that unless it's the 119 // last subtree for the current depth, the leaf count will be 120 // treeCapacity, otherwise it's what ever is left over after 121 // consuming treeCapacity chunks. 122 int pageCount = treeCapacity; 123 if (i == curNodes.count()) { 124 pageCount = ((pages.count() - 1) % treeCapacity) + 1; 125 } 126 newNode->insert(countName.get(), new SkPDFInt(pageCount))->unref(); 127 newNode->insert(kidsName.get(), kids.get()); 128 nextRoundNodes.push(newNode); // Transfer reference. 129 } 130 131 curNodes = nextRoundNodes; 132 nextRoundNodes.rewind(); 133 treeCapacity *= kNodeSize; 134 } while (curNodes.count() > 1); 135 136 pageTree->push(curNodes[0]); // Transfer reference. 137 catalog->addObject(curNodes[0], false); 138 if (rootNode) { 139 *rootNode = curNodes[0]; 140 } 141 } 142 143 const SkTDArray<SkPDFFont*>& SkPDFPage::getFontResources() const { 144 return fDevice->getFontResources(); 145 } 146 147 const SkPDFGlyphSetMap& SkPDFPage::getFontGlyphUsage() const { 148 return fDevice->getFontGlyphUsage(); 149 } 150