1
2 /*
3 * Copyright 2011 Google Inc.
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 #include "SkCanvas.h"
9 #include "SkColor.h"
10 #include "SkReadBuffer.h"
11 #include "SkWriteBuffer.h"
12 #include "SkLayerDrawLooper.h"
13 #include "SkString.h"
14 #include "SkStringUtils.h"
15 #include "SkUnPreMultiply.h"
16
LayerInfo()17 SkLayerDrawLooper::LayerInfo::LayerInfo() {
18 fPaintBits = 0; // ignore our paint fields
19 fColorMode = SkXfermode::kDst_Mode; // ignore our color
20 fOffset.set(0, 0);
21 fPostTranslate = false;
22 }
23
SkLayerDrawLooper()24 SkLayerDrawLooper::SkLayerDrawLooper()
25 : fRecs(nullptr),
26 fCount(0) {
27 }
28
~SkLayerDrawLooper()29 SkLayerDrawLooper::~SkLayerDrawLooper() {
30 Rec* rec = fRecs;
31 while (rec) {
32 Rec* next = rec->fNext;
33 delete rec;
34 rec = next;
35 }
36 }
37
createContext(SkCanvas * canvas,void * storage) const38 SkLayerDrawLooper::Context* SkLayerDrawLooper::createContext(SkCanvas* canvas, void* storage) const {
39 canvas->save();
40 return new (storage) LayerDrawLooperContext(this);
41 }
42
xferColor(SkColor src,SkColor dst,SkXfermode::Mode mode)43 static SkColor xferColor(SkColor src, SkColor dst, SkXfermode::Mode mode) {
44 switch (mode) {
45 case SkXfermode::kSrc_Mode:
46 return src;
47 case SkXfermode::kDst_Mode:
48 return dst;
49 default: {
50 SkPMColor pmS = SkPreMultiplyColor(src);
51 SkPMColor pmD = SkPreMultiplyColor(dst);
52 SkPMColor result = SkXfermode::GetProc(mode)(pmS, pmD);
53 return SkUnPreMultiply::PMColorToColor(result);
54 }
55 }
56 }
57
58 // Even with kEntirePaint_Bits, we always ensure that the master paint's
59 // text-encoding is respected, since that controls how we interpret the
60 // text/length parameters of a draw[Pos]Text call.
ApplyInfo(SkPaint * dst,const SkPaint & src,const LayerInfo & info)61 void SkLayerDrawLooper::LayerDrawLooperContext::ApplyInfo(
62 SkPaint* dst, const SkPaint& src, const LayerInfo& info) {
63
64 dst->setColor(xferColor(src.getColor(), dst->getColor(), info.fColorMode));
65
66 BitFlags bits = info.fPaintBits;
67 SkPaint::TextEncoding encoding = dst->getTextEncoding();
68
69 if (0 == bits) {
70 return;
71 }
72 if (kEntirePaint_Bits == bits) {
73 // we've already computed these, so save it from the assignment
74 uint32_t f = dst->getFlags();
75 SkColor c = dst->getColor();
76 *dst = src;
77 dst->setFlags(f);
78 dst->setColor(c);
79 dst->setTextEncoding(encoding);
80 return;
81 }
82
83 if (bits & kStyle_Bit) {
84 dst->setStyle(src.getStyle());
85 dst->setStrokeWidth(src.getStrokeWidth());
86 dst->setStrokeMiter(src.getStrokeMiter());
87 dst->setStrokeCap(src.getStrokeCap());
88 dst->setStrokeJoin(src.getStrokeJoin());
89 }
90
91 if (bits & kTextSkewX_Bit) {
92 dst->setTextSkewX(src.getTextSkewX());
93 }
94
95 if (bits & kPathEffect_Bit) {
96 dst->setPathEffect(src.getPathEffect());
97 }
98 if (bits & kMaskFilter_Bit) {
99 dst->setMaskFilter(src.getMaskFilter());
100 }
101 if (bits & kShader_Bit) {
102 dst->setShader(src.getShader());
103 }
104 if (bits & kColorFilter_Bit) {
105 dst->setColorFilter(src.getColorFilter());
106 }
107 if (bits & kXfermode_Bit) {
108 dst->setXfermode(src.getXfermode());
109 }
110
111 // we don't override these
112 #if 0
113 dst->setTypeface(src.getTypeface());
114 dst->setTextSize(src.getTextSize());
115 dst->setTextScaleX(src.getTextScaleX());
116 dst->setRasterizer(src.getRasterizer());
117 dst->setLooper(src.getLooper());
118 dst->setTextEncoding(src.getTextEncoding());
119 dst->setHinting(src.getHinting());
120 #endif
121 }
122
123 // Should we add this to canvas?
postTranslate(SkCanvas * canvas,SkScalar dx,SkScalar dy)124 static void postTranslate(SkCanvas* canvas, SkScalar dx, SkScalar dy) {
125 SkMatrix m = canvas->getTotalMatrix();
126 m.postTranslate(dx, dy);
127 canvas->setMatrix(m);
128 }
129
LayerDrawLooperContext(const SkLayerDrawLooper * looper)130 SkLayerDrawLooper::LayerDrawLooperContext::LayerDrawLooperContext(
131 const SkLayerDrawLooper* looper) : fCurrRec(looper->fRecs) {}
132
next(SkCanvas * canvas,SkPaint * paint)133 bool SkLayerDrawLooper::LayerDrawLooperContext::next(SkCanvas* canvas,
134 SkPaint* paint) {
135 canvas->restore();
136 if (nullptr == fCurrRec) {
137 return false;
138 }
139
140 ApplyInfo(paint, fCurrRec->fPaint, fCurrRec->fInfo);
141
142 canvas->save();
143 if (fCurrRec->fInfo.fPostTranslate) {
144 postTranslate(canvas, fCurrRec->fInfo.fOffset.fX,
145 fCurrRec->fInfo.fOffset.fY);
146 } else {
147 canvas->translate(fCurrRec->fInfo.fOffset.fX,
148 fCurrRec->fInfo.fOffset.fY);
149 }
150 fCurrRec = fCurrRec->fNext;
151
152 return true;
153 }
154
asABlurShadow(BlurShadowRec * bsRec) const155 bool SkLayerDrawLooper::asABlurShadow(BlurShadowRec* bsRec) const {
156 if (fCount != 2) {
157 return false;
158 }
159 const Rec* rec = fRecs;
160
161 // bottom layer needs to be just blur(maskfilter)
162 if ((rec->fInfo.fPaintBits & ~kMaskFilter_Bit)) {
163 return false;
164 }
165 if (SkXfermode::kSrc_Mode != rec->fInfo.fColorMode) {
166 return false;
167 }
168 const SkMaskFilter* mf = rec->fPaint.getMaskFilter();
169 if (nullptr == mf) {
170 return false;
171 }
172 SkMaskFilter::BlurRec maskBlur;
173 if (!mf->asABlur(&maskBlur)) {
174 return false;
175 }
176
177 rec = rec->fNext;
178 // top layer needs to be "plain"
179 if (rec->fInfo.fPaintBits) {
180 return false;
181 }
182 if (SkXfermode::kDst_Mode != rec->fInfo.fColorMode) {
183 return false;
184 }
185 if (!rec->fInfo.fOffset.equals(0, 0)) {
186 return false;
187 }
188
189 if (bsRec) {
190 bsRec->fSigma = maskBlur.fSigma;
191 bsRec->fOffset = fRecs->fInfo.fOffset;
192 bsRec->fColor = fRecs->fPaint.getColor();
193 bsRec->fStyle = maskBlur.fStyle;
194 bsRec->fQuality = maskBlur.fQuality;
195 }
196 return true;
197 }
198
199 ///////////////////////////////////////////////////////////////////////////////
200
flatten(SkWriteBuffer & buffer) const201 void SkLayerDrawLooper::flatten(SkWriteBuffer& buffer) const {
202 buffer.writeInt(fCount);
203
204 Rec* rec = fRecs;
205 for (int i = 0; i < fCount; i++) {
206 // Legacy "flagsmask" field -- now ignored, remove when we bump version
207 buffer.writeInt(0);
208
209 buffer.writeInt(rec->fInfo.fPaintBits);
210 buffer.writeInt(rec->fInfo.fColorMode);
211 buffer.writePoint(rec->fInfo.fOffset);
212 buffer.writeBool(rec->fInfo.fPostTranslate);
213 buffer.writePaint(rec->fPaint);
214 rec = rec->fNext;
215 }
216 }
217
CreateProc(SkReadBuffer & buffer)218 SkFlattenable* SkLayerDrawLooper::CreateProc(SkReadBuffer& buffer) {
219 int count = buffer.readInt();
220
221 Builder builder;
222 for (int i = 0; i < count; i++) {
223 LayerInfo info;
224 // Legacy "flagsmask" field -- now ignored, remove when we bump version
225 (void)buffer.readInt();
226
227 info.fPaintBits = buffer.readInt();
228 info.fColorMode = (SkXfermode::Mode)buffer.readInt();
229 buffer.readPoint(&info.fOffset);
230 info.fPostTranslate = buffer.readBool();
231 buffer.readPaint(builder.addLayerOnTop(info));
232 }
233 return builder.detachLooper();
234 }
235
236 #ifndef SK_IGNORE_TO_STRING
toString(SkString * str) const237 void SkLayerDrawLooper::toString(SkString* str) const {
238 str->appendf("SkLayerDrawLooper (%d): ", fCount);
239
240 Rec* rec = fRecs;
241 for (int i = 0; i < fCount; i++) {
242 str->appendf("%d: paintBits: (", i);
243 if (0 == rec->fInfo.fPaintBits) {
244 str->append("None");
245 } else if (kEntirePaint_Bits == rec->fInfo.fPaintBits) {
246 str->append("EntirePaint");
247 } else {
248 bool needSeparator = false;
249 SkAddFlagToString(str, SkToBool(kStyle_Bit & rec->fInfo.fPaintBits), "Style",
250 &needSeparator);
251 SkAddFlagToString(str, SkToBool(kTextSkewX_Bit & rec->fInfo.fPaintBits), "TextSkewX",
252 &needSeparator);
253 SkAddFlagToString(str, SkToBool(kPathEffect_Bit & rec->fInfo.fPaintBits), "PathEffect",
254 &needSeparator);
255 SkAddFlagToString(str, SkToBool(kMaskFilter_Bit & rec->fInfo.fPaintBits), "MaskFilter",
256 &needSeparator);
257 SkAddFlagToString(str, SkToBool(kShader_Bit & rec->fInfo.fPaintBits), "Shader",
258 &needSeparator);
259 SkAddFlagToString(str, SkToBool(kColorFilter_Bit & rec->fInfo.fPaintBits), "ColorFilter",
260 &needSeparator);
261 SkAddFlagToString(str, SkToBool(kXfermode_Bit & rec->fInfo.fPaintBits), "Xfermode",
262 &needSeparator);
263 }
264 str->append(") ");
265
266 static const char* gModeStrings[SkXfermode::kLastMode+1] = {
267 "kClear", "kSrc", "kDst", "kSrcOver", "kDstOver", "kSrcIn", "kDstIn",
268 "kSrcOut", "kDstOut", "kSrcATop", "kDstATop", "kXor", "kPlus",
269 "kMultiply", "kScreen", "kOverlay", "kDarken", "kLighten", "kColorDodge",
270 "kColorBurn", "kHardLight", "kSoftLight", "kDifference", "kExclusion"
271 };
272
273 str->appendf("mode: %s ", gModeStrings[rec->fInfo.fColorMode]);
274
275 str->append("offset: (");
276 str->appendScalar(rec->fInfo.fOffset.fX);
277 str->append(", ");
278 str->appendScalar(rec->fInfo.fOffset.fY);
279 str->append(") ");
280
281 str->append("postTranslate: ");
282 if (rec->fInfo.fPostTranslate) {
283 str->append("true ");
284 } else {
285 str->append("false ");
286 }
287
288 rec->fPaint.toString(str);
289 rec = rec->fNext;
290 }
291 }
292 #endif
293
Builder()294 SkLayerDrawLooper::Builder::Builder()
295 : fRecs(nullptr),
296 fTopRec(nullptr),
297 fCount(0) {
298 }
299
~Builder()300 SkLayerDrawLooper::Builder::~Builder() {
301 Rec* rec = fRecs;
302 while (rec) {
303 Rec* next = rec->fNext;
304 delete rec;
305 rec = next;
306 }
307 }
308
addLayer(const LayerInfo & info)309 SkPaint* SkLayerDrawLooper::Builder::addLayer(const LayerInfo& info) {
310 fCount += 1;
311
312 Rec* rec = new Rec;
313 rec->fNext = fRecs;
314 rec->fInfo = info;
315 fRecs = rec;
316 if (nullptr == fTopRec) {
317 fTopRec = rec;
318 }
319
320 return &rec->fPaint;
321 }
322
addLayer(SkScalar dx,SkScalar dy)323 void SkLayerDrawLooper::Builder::addLayer(SkScalar dx, SkScalar dy) {
324 LayerInfo info;
325
326 info.fOffset.set(dx, dy);
327 (void)this->addLayer(info);
328 }
329
addLayerOnTop(const LayerInfo & info)330 SkPaint* SkLayerDrawLooper::Builder::addLayerOnTop(const LayerInfo& info) {
331 fCount += 1;
332
333 Rec* rec = new Rec;
334 rec->fNext = nullptr;
335 rec->fInfo = info;
336 if (nullptr == fRecs) {
337 fRecs = rec;
338 } else {
339 SkASSERT(fTopRec);
340 fTopRec->fNext = rec;
341 }
342 fTopRec = rec;
343
344 return &rec->fPaint;
345 }
346
detachLooper()347 SkLayerDrawLooper* SkLayerDrawLooper::Builder::detachLooper() {
348 SkLayerDrawLooper* looper = new SkLayerDrawLooper;
349 looper->fCount = fCount;
350 looper->fRecs = fRecs;
351
352 fCount = 0;
353 fRecs = nullptr;
354 fTopRec = nullptr;
355
356 return looper;
357 }
358