1 /*
2 * Copyright 2018 Google Inc.
3 *
4 * Use of this source code is governed by a BSD-style license that can be
5 * found in the LICENSE file.
6 */
7 #include "include/core/SkBitmap.h"
8 #include "include/core/SkCanvas.h"
9 #include "include/core/SkColor.h"
10 #include "include/core/SkDocument.h"
11 #include "include/core/SkFont.h"
12 #include "include/core/SkImage.h" // IWYU pragma: keep
13 #include "include/core/SkPaint.h"
14 #include "include/core/SkRefCnt.h"
15 #include "include/core/SkSize.h"
16 #include "include/core/SkStream.h"
17 #include "include/core/SkString.h"
18 #include "include/core/SkTime.h"
19 #include "include/core/SkTypeface.h"
20 #include "include/docs/SkPDFDocument.h"
21 #include "tests/Test.h"
22
23 #include <memory>
24 #include <utility>
25 #include <vector>
26
27 using PDFTag = SkPDF::StructureElementNode;
28
29 // Test building a tagged PDF.
30 // Add this to args.gn to output the PDF to a file:
31 // extra_cflags = [ "-DSK_PDF_TEST_TAGS_OUTPUT_PATH=\"/tmp/foo.pdf\"" ]
DEF_TEST(SkPDF_tagged_doc,r)32 DEF_TEST(SkPDF_tagged_doc, r) {
33 REQUIRE_PDF_DOCUMENT(SkPDF_tagged_doc, r);
34 #ifdef SK_PDF_TEST_TAGS_OUTPUT_PATH
35 SkFILEWStream outputStream(SK_PDF_TEST_TAGS_OUTPUT_PATH);
36 #else
37 SkDynamicMemoryWStream outputStream;
38 #endif
39
40 SkSize pageSize = SkSize::Make(612, 792); // U.S. Letter
41
42 SkPDF::Metadata metadata;
43 metadata.fTitle = "Example Tagged PDF";
44 metadata.fCreator = "Skia";
45 SkTime::DateTime now;
46 SkTime::GetDateTime(&now);
47 metadata.fCreation = now;
48 metadata.fModified = now;
49
50 // The document tag.
51 auto root = std::make_unique<PDFTag>();
52 root->fNodeId = 1;
53 root->fTypeString = "Document";
54
55 // Heading.
56 auto h1 = std::make_unique<PDFTag>();
57 h1->fNodeId = 2;
58 h1->fTypeString = "H1";
59 root->fChildVector.push_back(std::move(h1));
60
61 // Initial paragraph.
62 auto p = std::make_unique<PDFTag>();
63 p->fNodeId = 3;
64 p->fTypeString = "P";
65 root->fChildVector.push_back(std::move(p));
66
67 // Hidden div. This is never referenced by marked content
68 // so it should not appear in the resulting PDF.
69 auto div = std::make_unique<PDFTag>();
70 div->fNodeId = 4;
71 div->fTypeString = "Div";
72 root->fChildVector.push_back(std::move(div));
73
74 // A bulleted list of two items.
75 auto l = std::make_unique<PDFTag>();
76 l->fNodeId = 5;
77 l->fTypeString = "L";
78
79 auto lm1 = std::make_unique<PDFTag>();
80 lm1->fNodeId = 6;
81 lm1->fTypeString = "Lbl";
82 l->fChildVector.push_back(std::move(lm1));
83
84 auto li1 = std::make_unique<PDFTag>();
85 li1->fNodeId = 7;
86 li1->fTypeString = "LI";
87 l->fChildVector.push_back(std::move(li1));
88
89 auto lm2 = std::make_unique<PDFTag>();
90 lm2->fNodeId = 8;
91 lm2->fTypeString = "Lbl";
92 l->fChildVector.push_back(std::move(lm2));
93 auto li2 = std::make_unique<PDFTag>();
94 li2->fNodeId = 9;
95 li2->fTypeString = "LI";
96 l->fChildVector.push_back(std::move(li2));
97
98 root->fChildVector.push_back(std::move(l));
99
100 // Paragraph spanning two pages.
101 auto p2 = std::make_unique<PDFTag>();
102 p2->fNodeId = 10;
103 p2->fTypeString = "P";
104 root->fChildVector.push_back(std::move(p2));
105
106 // Image with alt text.
107 auto img = std::make_unique<PDFTag>();
108 img->fNodeId = 11;
109 img->fTypeString = "Figure";
110 img->fAlt = "Red box";
111 root->fChildVector.push_back(std::move(img));
112
113 metadata.fStructureElementTreeRoot = root.get();
114 sk_sp<SkDocument> document = SkPDF::MakeDocument(
115 &outputStream, metadata);
116
117 SkPaint paint;
118 paint.setColor(SK_ColorBLACK);
119
120 // First page.
121 SkCanvas* canvas =
122 document->beginPage(pageSize.width(),
123 pageSize.height());
124 SkPDF::SetNodeId(canvas, 2);
125 SkFont font(nullptr, 36);
126 const char* message = "This is the title";
127 canvas->translate(72, 72);
128 canvas->drawString(message, 0, 0, font, paint);
129
130 SkPDF::SetNodeId(canvas, 3);
131 font.setSize(14);
132 message = "This is a simple paragraph.";
133 canvas->translate(0, 72);
134 canvas->drawString(message, 0, 0, font, paint);
135
136 SkPDF::SetNodeId(canvas, 6);
137 font.setSize(14);
138 message = "*";
139 canvas->translate(0, 72);
140 canvas->drawString(message, 0, 0, font, paint);
141
142 SkPDF::SetNodeId(canvas, 7);
143 message = "List item 1";
144 canvas->translate(36, 0);
145 canvas->drawString(message, 0, 0, font, paint);
146
147 SkPDF::SetNodeId(canvas, 8);
148 message = "*";
149 canvas->translate(-36, 36);
150 canvas->drawString(message, 0, 0, font, paint);
151
152 SkPDF::SetNodeId(canvas, 9);
153 message = "List item 2";
154 canvas->translate(36, 0);
155 canvas->drawString(message, 0, 0, font, paint);
156
157 SkPDF::SetNodeId(canvas, 10);
158 message = "This is a paragraph that starts on one page";
159 canvas->translate(-36, 6 * 72);
160 canvas->drawString(message, 0, 0, font, paint);
161
162 document->endPage();
163
164 // Second page.
165 canvas = document->beginPage(pageSize.width(),
166 pageSize.height());
167 SkPDF::SetNodeId(canvas, 10);
168 message = "and finishes on the second page.";
169 canvas->translate(72, 72);
170 canvas->drawString(message, 0, 0, font, paint);
171
172 // Test a tagged image with alt text.
173 SkPDF::SetNodeId(canvas, 11);
174 SkBitmap testBitmap;
175 testBitmap.allocN32Pixels(72, 72);
176 testBitmap.eraseColor(SK_ColorRED);
177 canvas->translate(72, 72);
178 canvas->drawImage(testBitmap.asImage(), 0, 0);
179
180 // This has a node ID but never shows up in the tag tree so it
181 // won't be tagged.
182 SkPDF::SetNodeId(canvas, 999);
183 message = "Page 2";
184 canvas->translate(468, -36);
185 canvas->drawString(message, 0, 0, font, paint);
186
187 document->endPage();
188
189 document->close();
190
191 outputStream.flush();
192 }
193