1// Copyright 2018 Google LLC.
2// Use of this source code is governed by a BSD-style license that can be found in the LICENSE file.
3#ifndef SkPDFDocument_DEFINED
4#define SkPDFDocument_DEFINED
5
6#include "include/core/SkDocument.h"
7
8#include <vector>
9
10#include "include/core/SkColor.h"
11#include "include/core/SkMilestone.h"
12#include "include/core/SkScalar.h"
13#include "include/core/SkString.h"
14#include "include/core/SkTime.h"
15#include "include/private/SkNoncopyable.h"
16
17#define SKPDF_STRING(X) SKPDF_STRING_IMPL(X)
18#define SKPDF_STRING_IMPL(X) #X
19
20class SkExecutor;
21class SkPDFArray;
22class SkPDFTagTree;
23
24namespace SkPDF {
25
26/** Table 333 in PDF 32000-1:2008 ยง14.8.4.2
27*/
28enum class DocumentStructureType {
29 kDocument, //!< Document
30 kPart, //!< Part
31 kArt, //!< Article
32 kSect, //!< Section
33 kDiv, //!< Division
34 kBlockQuote, //!< Block quotation
35 kCaption, //!< Caption
36 kTOC, //!< Table of Contents
37 kTOCI, //!< Table of Contents Item
38 kIndex, //!< Index
39 kNonStruct, //!< Nonstructural element
40 kPrivate, //!< Private element
41 kH, //!< Heading
42 kH1, //!< Heading level 1
43 kH2, //!< Heading level 2
44 kH3, //!< Heading level 3
45 kH4, //!< Heading level 4
46 kH5, //!< Heading level 5
47 kH6, //!< Heading level 6
48 kP, //!< Paragraph
49 kL, //!< List
50 kLI, //!< List item
51 kLbl, //!< List item label
52 kLBody, //!< List item body
53 kTable, //!< Table
54 kTR, //!< Table row
55 kTH, //!< Table header cell
56 kTD, //!< Table data cell
57 kTHead, //!< Table header row group
58 kTBody, //!< Table body row group
59 kTFoot, //!< table footer row group
60 kSpan, //!< Span
61 kQuote, //!< Quotation
62 kNote, //!< Note
63 kReference, //!< Reference
64 kBibEntry, //!< Bibliography entry
65 kCode, //!< Code
66 kLink, //!< Link
67 kAnnot, //!< Annotation
68 kRuby, //!< Ruby annotation
69 kRB, //!< Ruby base text
70 kRT, //!< Ruby annotation text
71 kRP, //!< Ruby punctuation
72 kWarichu, //!< Warichu annotation
73 kWT, //!< Warichu text
74 kWP, //!< Warichu punctuation
75 kFigure, //!< Figure
76 kFormula, //!< Formula
77 kForm, //!< Form control (not like an HTML FORM element)
78};
79
80/** Attributes for nodes in the PDF tree. */
81class SK_API AttributeList : SkNoncopyable {
82public:
83 AttributeList();
84 ~AttributeList();
85
86 // Each attribute must have an owner (e.g. "Layout", "List", "Table", etc)
87 // and an attribute name (e.g. "BBox", "RowSpan", etc.) from PDF32000_2008 14.8.5,
88 // and then a value of the proper type according to the spec.
89 void appendInt(const char* owner, const char* name, int value);
90 void appendFloat(const char* owner, const char* name, float value);
91 void appendName(const char* owner, const char* attrName, const char* value);
92 void appendString(const char* owner, const char* attrName, const char* value);
93 void appendFloatArray(const char* owner,
94 const char* name,
95 const std::vector<float>& value);
96 // Deprecated.
97 void appendStringArray(const char* owner,
98 const char* attrName,
99 const std::vector<SkString>& values);
100 void appendNodeIdArray(const char* owner,
101 const char* attrName,
102 const std::vector<int>& nodeIds);
103
104private:
105 friend class ::SkPDFTagTree;
106
107 std::unique_ptr<SkPDFArray> fAttrs;
108};
109
110/** A node in a PDF structure tree, giving a semantic representation
111 of the content. Each node ID is associated with content
112 by passing the SkCanvas and node ID to SkPDF::SetNodeId() when drawing.
113 NodeIDs should be unique within each tree.
114*/
115struct StructureElementNode {
116 SkString fTypeString;
117 std::vector<std::unique_ptr<StructureElementNode>> fChildVector;
118 int fNodeId = 0;
119 std::vector<int> fAdditionalNodeIds;
120 AttributeList fAttributes;
121 SkString fAlt;
122 SkString fLang;
123
124 // Deprecated. Use fTypeString instead.
125 DocumentStructureType fType = DocumentStructureType::kNonStruct;
126};
127
128/** Optional metadata to be passed into the PDF factory function.
129*/
130struct Metadata {
131 /** The document's title.
132 */
133 SkString fTitle;
134
135 /** The name of the person who created the document.
136 */
137 SkString fAuthor;
138
139 /** The subject of the document.
140 */
141 SkString fSubject;
142
143 /** Keywords associated with the document. Commas may be used to delineate
144 keywords within the string.
145 */
146 SkString fKeywords;
147
148 /** If the document was converted to PDF from another format,
149 the name of the conforming product that created the
150 original document from which it was converted.
151 */
152 SkString fCreator;
153
154 /** The product that is converting this document to PDF.
155 */
156 SkString fProducer = SkString("Skia/PDF m" SKPDF_STRING(SK_MILESTONE));
157
158 /** The date and time the document was created.
159 The zero default value represents an unknown/unset time.
160 */
161 SkTime::DateTime fCreation = {0, 0, 0, 0, 0, 0, 0, 0};
162
163 /** The date and time the document was most recently modified.
164 The zero default value represents an unknown/unset time.
165 */
166 SkTime::DateTime fModified = {0, 0, 0, 0, 0, 0, 0, 0};
167
168 /** The DPI (pixels-per-inch) at which features without native PDF support
169 will be rasterized (e.g. draw image with perspective, draw text with
170 perspective, ...) A larger DPI would create a PDF that reflects the
171 original intent with better fidelity, but it can make for larger PDF
172 files too, which would use more memory while rendering, and it would be
173 slower to be processed or sent online or to printer.
174 */
175 SkScalar fRasterDPI = SK_ScalarDefaultRasterDPI;
176
177 /** If true, include XMP metadata, a document UUID, and sRGB output intent
178 information. This adds length to the document and makes it
179 non-reproducable, but are necessary features for PDF/A-2b conformance
180 */
181 bool fPDFA = false;
182
183 /** Encoding quality controls the trade-off between size and quality. By
184 default this is set to 101 percent, which corresponds to lossless
185 encoding. If this value is set to a value <= 100, and the image is
186 opaque, it will be encoded (using JPEG) with that quality setting.
187 */
188 int fEncodingQuality = 101;
189
190 /** An optional tree of structured document tags that provide
191 a semantic representation of the content. The caller
192 should retain ownership.
193 */
194 StructureElementNode* fStructureElementTreeRoot = nullptr;
195
196 /** Executor to handle threaded work within PDF Backend. If this is nullptr,
197 then all work will be done serially on the main thread. To have worker
198 threads assist with various tasks, set this to a valid SkExecutor
199 instance. Currently used for executing Deflate algorithm in parallel.
200
201 If set, the PDF output will be non-reproducible in the order and
202 internal numbering of objects, but should render the same.
203
204 Experimental.
205 */
206 SkExecutor* fExecutor = nullptr;
207
208 /** Preferred Subsetter. Only respected if both are compiled in.
209
210 The Sfntly subsetter is deprecated.
211
212 Experimental.
213 */
214 enum Subsetter {
215 kHarfbuzz_Subsetter,
216 kSfntly_Subsetter,
217 } fSubsetter = kHarfbuzz_Subsetter;
218};
219
220/** Associate a node ID with subsequent drawing commands in an
221 SkCanvas. The same node ID can appear in a StructureElementNode
222 in order to associate a document's structure element tree with
223 its content.
224
225 A node ID of zero indicates no node ID.
226
227 @param canvas The canvas used to draw to the PDF.
228 @param nodeId The node ID for subsequent drawing commands.
229*/
230SK_API void SetNodeId(SkCanvas* dst, int nodeID);
231
232/** Create a PDF-backed document, writing the results into a SkWStream.
233
234 PDF pages are sized in point units. 1 pt == 1/72 inch == 127/360 mm.
235
236 @param stream A PDF document will be written to this stream. The document may write
237 to the stream at anytime during its lifetime, until either close() is
238 called or the document is deleted.
239 @param metadata a PDFmetadata object. Any fields may be left empty.
240
241 @returns NULL if there is an error, otherwise a newly created PDF-backed SkDocument.
242*/
243SK_API sk_sp<SkDocument> MakeDocument(SkWStream* stream, const Metadata& metadata);
244
245static inline sk_sp<SkDocument> MakeDocument(SkWStream* stream) {
246 return MakeDocument(stream, Metadata());
247}
248
249} // namespace SkPDF
250
251#undef SKPDF_STRING
252#undef SKPDF_STRING_IMPL
253#endif // SkPDFDocument_DEFINED
254