1 /*
2 * Copyright 2011 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
8 #include "SkPDFUtils.h"
9
10 #include "SkData.h"
11 #include "SkFixed.h"
12 #include "SkGeometry.h"
13 #include "SkImage_Base.h"
14 #include "SkPDFResourceDict.h"
15 #include "SkPDFTypes.h"
16 #include "SkStream.h"
17 #include "SkString.h"
18
19 #include <cmath>
20
RectToArray(const SkRect & rect)21 sk_sp<SkPDFArray> SkPDFUtils::RectToArray(const SkRect& rect) {
22 auto result = sk_make_sp<SkPDFArray>();
23 result->reserve(4);
24 result->appendScalar(rect.fLeft);
25 result->appendScalar(rect.fTop);
26 result->appendScalar(rect.fRight);
27 result->appendScalar(rect.fBottom);
28 return result;
29 }
30
MatrixToArray(const SkMatrix & matrix)31 sk_sp<SkPDFArray> SkPDFUtils::MatrixToArray(const SkMatrix& matrix) {
32 SkScalar values[6];
33 if (!matrix.asAffine(values)) {
34 SkMatrix::SetAffineIdentity(values);
35 }
36
37 auto result = sk_make_sp<SkPDFArray>();
38 result->reserve(6);
39 for (size_t i = 0; i < SK_ARRAY_COUNT(values); i++) {
40 result->appendScalar(values[i]);
41 }
42 return result;
43 }
44
45 // static
AppendTransform(const SkMatrix & matrix,SkWStream * content)46 void SkPDFUtils::AppendTransform(const SkMatrix& matrix, SkWStream* content) {
47 SkScalar values[6];
48 if (!matrix.asAffine(values)) {
49 SkMatrix::SetAffineIdentity(values);
50 }
51 for (size_t i = 0; i < SK_ARRAY_COUNT(values); i++) {
52 SkPDFUtils::AppendScalar(values[i], content);
53 content->writeText(" ");
54 }
55 content->writeText("cm\n");
56 }
57
58 // static
MoveTo(SkScalar x,SkScalar y,SkWStream * content)59 void SkPDFUtils::MoveTo(SkScalar x, SkScalar y, SkWStream* content) {
60 SkPDFUtils::AppendScalar(x, content);
61 content->writeText(" ");
62 SkPDFUtils::AppendScalar(y, content);
63 content->writeText(" m\n");
64 }
65
66 // static
AppendLine(SkScalar x,SkScalar y,SkWStream * content)67 void SkPDFUtils::AppendLine(SkScalar x, SkScalar y, SkWStream* content) {
68 SkPDFUtils::AppendScalar(x, content);
69 content->writeText(" ");
70 SkPDFUtils::AppendScalar(y, content);
71 content->writeText(" l\n");
72 }
73
74 // static
AppendCubic(SkScalar ctl1X,SkScalar ctl1Y,SkScalar ctl2X,SkScalar ctl2Y,SkScalar dstX,SkScalar dstY,SkWStream * content)75 void SkPDFUtils::AppendCubic(SkScalar ctl1X, SkScalar ctl1Y,
76 SkScalar ctl2X, SkScalar ctl2Y,
77 SkScalar dstX, SkScalar dstY, SkWStream* content) {
78 SkString cmd("y\n");
79 SkPDFUtils::AppendScalar(ctl1X, content);
80 content->writeText(" ");
81 SkPDFUtils::AppendScalar(ctl1Y, content);
82 content->writeText(" ");
83 if (ctl2X != dstX || ctl2Y != dstY) {
84 cmd.set("c\n");
85 SkPDFUtils::AppendScalar(ctl2X, content);
86 content->writeText(" ");
87 SkPDFUtils::AppendScalar(ctl2Y, content);
88 content->writeText(" ");
89 }
90 SkPDFUtils::AppendScalar(dstX, content);
91 content->writeText(" ");
92 SkPDFUtils::AppendScalar(dstY, content);
93 content->writeText(" ");
94 content->writeText(cmd.c_str());
95 }
96
append_quad(const SkPoint quad[],SkWStream * content)97 static void append_quad(const SkPoint quad[], SkWStream* content) {
98 SkPoint cubic[4];
99 SkConvertQuadToCubic(quad, cubic);
100 SkPDFUtils::AppendCubic(cubic[1].fX, cubic[1].fY, cubic[2].fX, cubic[2].fY,
101 cubic[3].fX, cubic[3].fY, content);
102 }
103
104 // static
AppendRectangle(const SkRect & rect,SkWStream * content)105 void SkPDFUtils::AppendRectangle(const SkRect& rect, SkWStream* content) {
106 // Skia has 0,0 at top left, pdf at bottom left. Do the right thing.
107 SkScalar bottom = SkMinScalar(rect.fBottom, rect.fTop);
108
109 SkPDFUtils::AppendScalar(rect.fLeft, content);
110 content->writeText(" ");
111 SkPDFUtils::AppendScalar(bottom, content);
112 content->writeText(" ");
113 SkPDFUtils::AppendScalar(rect.width(), content);
114 content->writeText(" ");
115 SkPDFUtils::AppendScalar(rect.height(), content);
116 content->writeText(" re\n");
117 }
118
119 // static
EmitPath(const SkPath & path,SkPaint::Style paintStyle,bool doConsumeDegerates,SkWStream * content,SkScalar tolerance)120 void SkPDFUtils::EmitPath(const SkPath& path, SkPaint::Style paintStyle,
121 bool doConsumeDegerates, SkWStream* content,
122 SkScalar tolerance) {
123 // Filling a path with no area results in a drawing in PDF renderers but
124 // Chrome expects to be able to draw some such entities with no visible
125 // result, so we detect those cases and discard the drawing for them.
126 // Specifically: moveTo(X), lineTo(Y) and moveTo(X), lineTo(X), lineTo(Y).
127
128 SkRect rect;
129 bool isClosed; // Both closure and direction need to be checked.
130 SkPath::Direction direction;
131 if (path.isRect(&rect, &isClosed, &direction) &&
132 isClosed &&
133 (SkPath::kCW_Direction == direction ||
134 SkPath::kEvenOdd_FillType == path.getFillType()))
135 {
136 SkPDFUtils::AppendRectangle(rect, content);
137 return;
138 }
139
140 enum SkipFillState {
141 kEmpty_SkipFillState,
142 kSingleLine_SkipFillState,
143 kNonSingleLine_SkipFillState,
144 };
145 SkipFillState fillState = kEmpty_SkipFillState;
146 //if (paintStyle != SkPaint::kFill_Style) {
147 // fillState = kNonSingleLine_SkipFillState;
148 //}
149 SkPoint lastMovePt = SkPoint::Make(0,0);
150 SkDynamicMemoryWStream currentSegment;
151 SkPoint args[4];
152 SkPath::Iter iter(path, false);
153 for (SkPath::Verb verb = iter.next(args, doConsumeDegerates);
154 verb != SkPath::kDone_Verb;
155 verb = iter.next(args, doConsumeDegerates)) {
156 // args gets all the points, even the implicit first point.
157 switch (verb) {
158 case SkPath::kMove_Verb:
159 MoveTo(args[0].fX, args[0].fY, ¤tSegment);
160 lastMovePt = args[0];
161 fillState = kEmpty_SkipFillState;
162 break;
163 case SkPath::kLine_Verb:
164 AppendLine(args[1].fX, args[1].fY, ¤tSegment);
165 if ((fillState == kEmpty_SkipFillState) && (args[0] != lastMovePt)) {
166 fillState = kSingleLine_SkipFillState;
167 break;
168 }
169 fillState = kNonSingleLine_SkipFillState;
170 break;
171 case SkPath::kQuad_Verb:
172 append_quad(args, ¤tSegment);
173 fillState = kNonSingleLine_SkipFillState;
174 break;
175 case SkPath::kConic_Verb: {
176 SkAutoConicToQuads converter;
177 const SkPoint* quads = converter.computeQuads(args, iter.conicWeight(), tolerance);
178 for (int i = 0; i < converter.countQuads(); ++i) {
179 append_quad(&quads[i * 2], ¤tSegment);
180 }
181 fillState = kNonSingleLine_SkipFillState;
182 } break;
183 case SkPath::kCubic_Verb:
184 AppendCubic(args[1].fX, args[1].fY, args[2].fX, args[2].fY,
185 args[3].fX, args[3].fY, ¤tSegment);
186 fillState = kNonSingleLine_SkipFillState;
187 break;
188 case SkPath::kClose_Verb:
189 ClosePath(¤tSegment);
190 currentSegment.writeToStream(content);
191 currentSegment.reset();
192 break;
193 default:
194 SkASSERT(false);
195 break;
196 }
197 }
198 if (currentSegment.bytesWritten() > 0) {
199 currentSegment.writeToStream(content);
200 }
201 }
202
203 // static
ClosePath(SkWStream * content)204 void SkPDFUtils::ClosePath(SkWStream* content) {
205 content->writeText("h\n");
206 }
207
208 // static
PaintPath(SkPaint::Style style,SkPath::FillType fill,SkWStream * content)209 void SkPDFUtils::PaintPath(SkPaint::Style style, SkPath::FillType fill,
210 SkWStream* content) {
211 if (style == SkPaint::kFill_Style) {
212 content->writeText("f");
213 } else if (style == SkPaint::kStrokeAndFill_Style) {
214 content->writeText("B");
215 } else if (style == SkPaint::kStroke_Style) {
216 content->writeText("S");
217 }
218
219 if (style != SkPaint::kStroke_Style) {
220 NOT_IMPLEMENTED(fill == SkPath::kInverseEvenOdd_FillType, false);
221 NOT_IMPLEMENTED(fill == SkPath::kInverseWinding_FillType, false);
222 if (fill == SkPath::kEvenOdd_FillType) {
223 content->writeText("*");
224 }
225 }
226 content->writeText("\n");
227 }
228
229 // static
StrokePath(SkWStream * content)230 void SkPDFUtils::StrokePath(SkWStream* content) {
231 SkPDFUtils::PaintPath(
232 SkPaint::kStroke_Style, SkPath::kWinding_FillType, content);
233 }
234
235 // static
DrawFormXObject(int objectIndex,SkWStream * content)236 void SkPDFUtils::DrawFormXObject(int objectIndex, SkWStream* content) {
237 content->writeText("/");
238 content->writeText(SkPDFResourceDict::getResourceName(
239 SkPDFResourceDict::kXObject_ResourceType,
240 objectIndex).c_str());
241 content->writeText(" Do\n");
242 }
243
244 // static
ApplyGraphicState(int objectIndex,SkWStream * content)245 void SkPDFUtils::ApplyGraphicState(int objectIndex, SkWStream* content) {
246 content->writeText("/");
247 content->writeText(SkPDFResourceDict::getResourceName(
248 SkPDFResourceDict::kExtGState_ResourceType,
249 objectIndex).c_str());
250 content->writeText(" gs\n");
251 }
252
253 // static
ApplyPattern(int objectIndex,SkWStream * content)254 void SkPDFUtils::ApplyPattern(int objectIndex, SkWStream* content) {
255 // Select Pattern color space (CS, cs) and set pattern object as current
256 // color (SCN, scn)
257 SkString resourceName = SkPDFResourceDict::getResourceName(
258 SkPDFResourceDict::kPattern_ResourceType,
259 objectIndex);
260 content->writeText("/Pattern CS/Pattern cs/");
261 content->writeText(resourceName.c_str());
262 content->writeText(" SCN/");
263 content->writeText(resourceName.c_str());
264 content->writeText(" scn\n");
265 }
266
ColorToDecimal(uint8_t value,char result[5])267 size_t SkPDFUtils::ColorToDecimal(uint8_t value, char result[5]) {
268 if (value == 255 || value == 0) {
269 result[0] = value ? '1' : '0';
270 result[1] = '\0';
271 return 1;
272 }
273 // int x = 0.5 + (1000.0 / 255.0) * value;
274 int x = SkFixedRoundToInt((SK_Fixed1 * 1000 / 255) * value);
275 result[0] = '.';
276 for (int i = 3; i > 0; --i) {
277 result[i] = '0' + x % 10;
278 x /= 10;
279 }
280 int j;
281 for (j = 3; j > 1; --j) {
282 if (result[j] != '0') {
283 break;
284 }
285 }
286 result[j + 1] = '\0';
287 return j + 1;
288 }
289
WriteString(SkWStream * wStream,const char * cin,size_t len)290 void SkPDFUtils::WriteString(SkWStream* wStream, const char* cin, size_t len) {
291 SkDEBUGCODE(static const size_t kMaxLen = 65535;)
292 SkASSERT(len <= kMaxLen);
293
294 size_t extraCharacterCount = 0;
295 for (size_t i = 0; i < len; i++) {
296 if (cin[i] > '~' || cin[i] < ' ') {
297 extraCharacterCount += 3;
298 }
299 if (cin[i] == '\\' || cin[i] == '(' || cin[i] == ')') {
300 ++extraCharacterCount;
301 }
302 }
303 if (extraCharacterCount <= len) {
304 wStream->writeText("(");
305 for (size_t i = 0; i < len; i++) {
306 if (cin[i] > '~' || cin[i] < ' ') {
307 uint8_t c = static_cast<uint8_t>(cin[i]);
308 uint8_t octal[4];
309 octal[0] = '\\';
310 octal[1] = '0' + ( c >> 6 );
311 octal[2] = '0' + ((c >> 3) & 0x07);
312 octal[3] = '0' + ( c & 0x07);
313 wStream->write(octal, 4);
314 } else {
315 if (cin[i] == '\\' || cin[i] == '(' || cin[i] == ')') {
316 wStream->writeText("\\");
317 }
318 wStream->write(&cin[i], 1);
319 }
320 }
321 wStream->writeText(")");
322 } else {
323 wStream->writeText("<");
324 for (size_t i = 0; i < len; i++) {
325 uint8_t c = static_cast<uint8_t>(cin[i]);
326 char hexValue[2] = { SkHexadecimalDigits::gUpper[c >> 4],
327 SkHexadecimalDigits::gUpper[c & 0xF] };
328 wStream->write(hexValue, 2);
329 }
330 wStream->writeText(">");
331 }
332 }
333
InverseTransformBBox(const SkMatrix & matrix,SkRect * bbox)334 bool SkPDFUtils::InverseTransformBBox(const SkMatrix& matrix, SkRect* bbox) {
335 SkMatrix inverse;
336 if (!matrix.invert(&inverse)) {
337 return false;
338 }
339 inverse.mapRect(bbox);
340 return true;
341 }
342
PopulateTilingPatternDict(SkPDFDict * pattern,SkRect & bbox,sk_sp<SkPDFDict> resources,const SkMatrix & matrix)343 void SkPDFUtils::PopulateTilingPatternDict(SkPDFDict* pattern,
344 SkRect& bbox,
345 sk_sp<SkPDFDict> resources,
346 const SkMatrix& matrix) {
347 const int kTiling_PatternType = 1;
348 const int kColoredTilingPattern_PaintType = 1;
349 const int kConstantSpacing_TilingType = 1;
350
351 pattern->insertName("Type", "Pattern");
352 pattern->insertInt("PatternType", kTiling_PatternType);
353 pattern->insertInt("PaintType", kColoredTilingPattern_PaintType);
354 pattern->insertInt("TilingType", kConstantSpacing_TilingType);
355 pattern->insertObject("BBox", SkPDFUtils::RectToArray(bbox));
356 pattern->insertScalar("XStep", bbox.width());
357 pattern->insertScalar("YStep", bbox.height());
358 pattern->insertObject("Resources", std::move(resources));
359 if (!matrix.isIdentity()) {
360 pattern->insertObject("Matrix", SkPDFUtils::MatrixToArray(matrix));
361 }
362 }
363
ToBitmap(const SkImage * img,SkBitmap * dst)364 bool SkPDFUtils::ToBitmap(const SkImage* img, SkBitmap* dst) {
365 SkASSERT(img);
366 SkASSERT(dst);
367 SkBitmap bitmap;
368 if(as_IB(img)->getROPixels(&bitmap, nullptr)) {
369 SkASSERT(bitmap.dimensions() == img->dimensions());
370 SkASSERT(!bitmap.drawsNothing());
371 *dst = std::move(bitmap);
372 return true;
373 }
374 return false;
375 }
376