1// Copyright 2019 Google LLC. 2// Use of this source code is governed by a BSD-style license that can be found in the LICENSE file. 3#include "tools/fiddle/examples.h" 4REG_FIDDLE(PDF, 256, 256, true, 0) { 5 6// Here is an example of using Skia’s PDF backend (SkPDF) via the SkDocument 7// and SkCanvas APIs. 8void WritePDF(SkWStream* outputStream, 9 const char* documentTitle, 10 void (*writePage)(SkCanvas*, int page), 11 int numberOfPages, 12 SkSize pageSize) { 13 SkPDF::Metadata metadata; 14 metadata.fTitle = documentTitle; 15 metadata.fCreator = "Example WritePDF() Function"; 16 metadata.fCreation = {0, 2019, 1, 4, 31, 12, 34, 56}; 17 metadata.fModified = {0, 2019, 1, 4, 31, 12, 34, 56}; 18 auto pdfDocument = SkPDF::MakeDocument(outputStream, metadata); 19 SkASSERT(pdfDocument); 20 for (int page = 0; page < numberOfPages; ++page) { 21 SkCanvas* pageCanvas = pdfDocument->beginPage(pageSize.width(), 22 pageSize.height()); 23 writePage(pageCanvas, page); 24 pdfDocument->endPage(); 25 } 26 pdfDocument->close(); 27} 28 29// Print binary data to stdout as hex. 30void print_data(const SkData* data, const char* name) { 31 if (data) { 32 SkDebugf("\nxxd -r -p > %s << EOF", name); 33 size_t s = data->size(); 34 const uint8_t* d = data->bytes(); 35 for (size_t i = 0; i < s; ++i) { 36 if (i % 40 == 0) { SkDebugf("\n"); } 37 SkDebugf("%02x", d[i]); 38 } 39 SkDebugf("\nEOF\n\n"); 40 } 41} 42 43// example function that draws on a SkCanvas. 44void write_page(SkCanvas* canvas, int) { 45 const SkScalar R = 115.2f, C = 128.0f; 46 SkPath path; 47 path.moveTo(C + R, C); 48 for (int i = 1; i < 8; ++i) { 49 SkScalar a = 2.6927937f * i; 50 path.lineTo(C + R * cos(a), C + R * sin(a)); 51 } 52 SkPaint paint; 53 paint.setStyle(SkPaint::kStroke_Style); 54 canvas->drawPath(path, paint); 55} 56 57void draw(SkCanvas*) { 58 constexpr SkSize ansiLetterSize{8.5f * 72, 11.0f * 72}; 59 SkDynamicMemoryWStream buffer; 60 WritePDF(&buffer, "SkPDF Example", &write_page, 1, ansiLetterSize); 61 sk_sp<SkData> pdfData = buffer.detachAsData(); 62 print_data(pdfData.get(), "skpdf_example.pdf"); 63} 64} // END FIDDLE 65