1 /*
2 * Copyright 2006 The Android Open Source Project
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 "SkArenaAlloc.h"
9 #include "SkAtomics.h"
10 #include "SkBitmapProcShader.h"
11 #include "SkColorShader.h"
12 #include "SkEmptyShader.h"
13 #include "SkMallocPixelRef.h"
14 #include "SkPaint.h"
15 #include "SkPicture.h"
16 #include "SkPictureShader.h"
17 #include "SkPM4fPriv.h"
18 #include "SkRasterPipeline.h"
19 #include "SkReadBuffer.h"
20 #include "SkScalar.h"
21 #include "SkShader.h"
22 #include "SkTLazy.h"
23 #include "SkWriteBuffer.h"
24
25 #if SK_SUPPORT_GPU
26 #include "GrFragmentProcessor.h"
27 #endif
28
29 //#define SK_TRACK_SHADER_LIFETIME
30
31 #ifdef SK_TRACK_SHADER_LIFETIME
32 static int32_t gShaderCounter;
33 #endif
34
inc_shader_counter()35 static inline void inc_shader_counter() {
36 #ifdef SK_TRACK_SHADER_LIFETIME
37 int32_t prev = sk_atomic_inc(&gShaderCounter);
38 SkDebugf("+++ shader counter %d\n", prev + 1);
39 #endif
40 }
dec_shader_counter()41 static inline void dec_shader_counter() {
42 #ifdef SK_TRACK_SHADER_LIFETIME
43 int32_t prev = sk_atomic_dec(&gShaderCounter);
44 SkDebugf("--- shader counter %d\n", prev - 1);
45 #endif
46 }
47
SkShader(const SkMatrix * localMatrix)48 SkShader::SkShader(const SkMatrix* localMatrix) {
49 inc_shader_counter();
50 if (localMatrix) {
51 fLocalMatrix = *localMatrix;
52 } else {
53 fLocalMatrix.reset();
54 }
55 // Pre-cache so future calls to fLocalMatrix.getType() are threadsafe.
56 (void)fLocalMatrix.getType();
57 }
58
~SkShader()59 SkShader::~SkShader() {
60 dec_shader_counter();
61 }
62
flatten(SkWriteBuffer & buffer) const63 void SkShader::flatten(SkWriteBuffer& buffer) const {
64 this->INHERITED::flatten(buffer);
65 bool hasLocalM = !fLocalMatrix.isIdentity();
66 buffer.writeBool(hasLocalM);
67 if (hasLocalM) {
68 buffer.writeMatrix(fLocalMatrix);
69 }
70 }
71
computeTotalInverse(const ContextRec & rec,SkMatrix * totalInverse) const72 bool SkShader::computeTotalInverse(const ContextRec& rec, SkMatrix* totalInverse) const {
73 SkMatrix total = SkMatrix::Concat(*rec.fMatrix, fLocalMatrix);
74 if (rec.fLocalMatrix) {
75 total.preConcat(*rec.fLocalMatrix);
76 }
77
78 return total.invert(totalInverse);
79 }
80
asLuminanceColor(SkColor * colorPtr) const81 bool SkShader::asLuminanceColor(SkColor* colorPtr) const {
82 SkColor storage;
83 if (nullptr == colorPtr) {
84 colorPtr = &storage;
85 }
86 if (this->onAsLuminanceColor(colorPtr)) {
87 *colorPtr = SkColorSetA(*colorPtr, 0xFF); // we only return opaque
88 return true;
89 }
90 return false;
91 }
92
makeContext(const ContextRec & rec,SkArenaAlloc * alloc) const93 SkShader::Context* SkShader::makeContext(const ContextRec& rec, SkArenaAlloc* alloc) const {
94 if (!this->computeTotalInverse(rec, nullptr)) {
95 return nullptr;
96 }
97 return this->onMakeContext(rec, alloc);
98 }
99
Context(const SkShader & shader,const ContextRec & rec)100 SkShader::Context::Context(const SkShader& shader, const ContextRec& rec)
101 : fShader(shader), fCTM(*rec.fMatrix)
102 {
103 // Because the context parameters must be valid at this point, we know that the matrix is
104 // invertible.
105 SkAssertResult(fShader.computeTotalInverse(rec, &fTotalInverse));
106 fTotalInverseClass = (uint8_t)ComputeMatrixClass(fTotalInverse);
107
108 fPaintAlpha = rec.fPaint->getAlpha();
109 }
110
~Context()111 SkShader::Context::~Context() {}
112
asAShadeProc(void ** ctx)113 SkShader::Context::ShadeProc SkShader::Context::asAShadeProc(void** ctx) {
114 return nullptr;
115 }
116
shadeSpan4f(int x,int y,SkPM4f dst[],int count)117 void SkShader::Context::shadeSpan4f(int x, int y, SkPM4f dst[], int count) {
118 const int N = 128;
119 SkPMColor tmp[N];
120 while (count > 0) {
121 int n = SkTMin(count, N);
122 this->shadeSpan(x, y, tmp, n);
123 for (int i = 0; i < n; ++i) {
124 dst[i] = SkPM4f::FromPMColor(tmp[i]);
125 }
126 dst += n;
127 x += n;
128 count -= n;
129 }
130 }
131
132 #include "SkColorPriv.h"
133
134 #define kTempColorQuadCount 6 // balance between speed (larger) and saving stack-space
135 #define kTempColorCount (kTempColorQuadCount << 2)
136
137 #ifdef SK_CPU_BENDIAN
138 #define SkU32BitShiftToByteOffset(shift) (3 - ((shift) >> 3))
139 #else
140 #define SkU32BitShiftToByteOffset(shift) ((shift) >> 3)
141 #endif
142
shadeSpanAlpha(int x,int y,uint8_t alpha[],int count)143 void SkShader::Context::shadeSpanAlpha(int x, int y, uint8_t alpha[], int count) {
144 SkASSERT(count > 0);
145
146 SkPMColor colors[kTempColorCount];
147
148 while ((count -= kTempColorCount) >= 0) {
149 this->shadeSpan(x, y, colors, kTempColorCount);
150 x += kTempColorCount;
151
152 const uint8_t* srcA = (const uint8_t*)colors + SkU32BitShiftToByteOffset(SK_A32_SHIFT);
153 int quads = kTempColorQuadCount;
154 do {
155 U8CPU a0 = srcA[0];
156 U8CPU a1 = srcA[4];
157 U8CPU a2 = srcA[8];
158 U8CPU a3 = srcA[12];
159 srcA += 4*4;
160 *alpha++ = SkToU8(a0);
161 *alpha++ = SkToU8(a1);
162 *alpha++ = SkToU8(a2);
163 *alpha++ = SkToU8(a3);
164 } while (--quads != 0);
165 }
166 SkASSERT(count < 0);
167 SkASSERT(count + kTempColorCount >= 0);
168 if (count += kTempColorCount) {
169 this->shadeSpan(x, y, colors, count);
170
171 const uint8_t* srcA = (const uint8_t*)colors + SkU32BitShiftToByteOffset(SK_A32_SHIFT);
172 do {
173 *alpha++ = *srcA;
174 srcA += 4;
175 } while (--count != 0);
176 }
177 #if 0
178 do {
179 int n = count;
180 if (n > kTempColorCount)
181 n = kTempColorCount;
182 SkASSERT(n > 0);
183
184 this->shadeSpan(x, y, colors, n);
185 x += n;
186 count -= n;
187
188 const uint8_t* srcA = (const uint8_t*)colors + SkU32BitShiftToByteOffset(SK_A32_SHIFT);
189 do {
190 *alpha++ = *srcA;
191 srcA += 4;
192 } while (--n != 0);
193 } while (count > 0);
194 #endif
195 }
196
ComputeMatrixClass(const SkMatrix & mat)197 SkShader::Context::MatrixClass SkShader::Context::ComputeMatrixClass(const SkMatrix& mat) {
198 MatrixClass mc = kLinear_MatrixClass;
199
200 if (mat.hasPerspective()) {
201 if (mat.isFixedStepInX()) {
202 mc = kFixedStepInX_MatrixClass;
203 } else {
204 mc = kPerspective_MatrixClass;
205 }
206 }
207 return mc;
208 }
209
210 //////////////////////////////////////////////////////////////////////////////
211
asAGradient(GradientInfo * info) const212 SkShader::GradientType SkShader::asAGradient(GradientInfo* info) const {
213 return kNone_GradientType;
214 }
215
216 #if SK_SUPPORT_GPU
asFragmentProcessor(const AsFPArgs &) const217 sk_sp<GrFragmentProcessor> SkShader::asFragmentProcessor(const AsFPArgs&) const {
218 return nullptr;
219 }
220 #endif
221
makeAsALocalMatrixShader(SkMatrix *) const222 sk_sp<SkShader> SkShader::makeAsALocalMatrixShader(SkMatrix*) const {
223 return nullptr;
224 }
225
MakeEmptyShader()226 sk_sp<SkShader> SkShader::MakeEmptyShader() { return sk_make_sp<SkEmptyShader>(); }
227
MakeColorShader(SkColor color)228 sk_sp<SkShader> SkShader::MakeColorShader(SkColor color) { return sk_make_sp<SkColorShader>(color); }
229
MakeBitmapShader(const SkBitmap & src,TileMode tmx,TileMode tmy,const SkMatrix * localMatrix)230 sk_sp<SkShader> SkShader::MakeBitmapShader(const SkBitmap& src, TileMode tmx, TileMode tmy,
231 const SkMatrix* localMatrix) {
232 if (localMatrix && !localMatrix->invert(nullptr)) {
233 return nullptr;
234 }
235 return SkMakeBitmapShader(src, tmx, tmy, localMatrix, kIfMutable_SkCopyPixelsMode);
236 }
237
MakePictureShader(sk_sp<SkPicture> src,TileMode tmx,TileMode tmy,const SkMatrix * localMatrix,const SkRect * tile)238 sk_sp<SkShader> SkShader::MakePictureShader(sk_sp<SkPicture> src, TileMode tmx, TileMode tmy,
239 const SkMatrix* localMatrix, const SkRect* tile) {
240 if (localMatrix && !localMatrix->invert(nullptr)) {
241 return nullptr;
242 }
243 return SkPictureShader::Make(std::move(src), tmx, tmy, localMatrix, tile);
244 }
245
246 #ifndef SK_IGNORE_TO_STRING
toString(SkString * str) const247 void SkShader::toString(SkString* str) const {
248 if (!fLocalMatrix.isIdentity()) {
249 str->append(" ");
250 fLocalMatrix.toString(str);
251 }
252 }
253 #endif
254
appendStages(SkRasterPipeline * pipeline,SkColorSpace * dst,SkArenaAlloc * scratch,const SkMatrix & ctm,const SkPaint & paint) const255 bool SkShader::appendStages(SkRasterPipeline* pipeline,
256 SkColorSpace* dst,
257 SkArenaAlloc* scratch,
258 const SkMatrix& ctm,
259 const SkPaint& paint) const {
260 return this->onAppendStages(pipeline, dst, scratch, ctm, paint, nullptr);
261 }
262
onAppendStages(SkRasterPipeline * p,SkColorSpace * cs,SkArenaAlloc * alloc,const SkMatrix & ctm,const SkPaint & paint,const SkMatrix * localM) const263 bool SkShader::onAppendStages(SkRasterPipeline* p,
264 SkColorSpace* cs,
265 SkArenaAlloc* alloc,
266 const SkMatrix& ctm,
267 const SkPaint& paint,
268 const SkMatrix* localM) const {
269 // Legacy shaders handle the paint opacity internally,
270 // but RP applies it as a separate stage.
271 SkTCopyOnFirstWrite<SkPaint> opaquePaint(paint);
272 if (paint.getAlpha() != SK_AlphaOPAQUE) {
273 opaquePaint.writable()->setAlpha(SK_AlphaOPAQUE);
274 }
275
276 ContextRec rec(*opaquePaint, ctm, localM, ContextRec::kPM4f_DstType, cs);
277 if (auto* ctx = this->makeContext(rec, alloc)) {
278 p->append(SkRasterPipeline::shader_adapter, ctx);
279
280 // Legacy shaders aren't aware of color spaces. We can pretty
281 // safely assume they're in sRGB gamut.
282 return append_gamut_transform(p, alloc,
283 SkColorSpace::MakeSRGB().get(), cs);
284 }
285 return false;
286 }
287
288 ///////////////////////////////////////////////////////////////////////////////////////////////////
289
CreateProc(SkReadBuffer &)290 sk_sp<SkFlattenable> SkEmptyShader::CreateProc(SkReadBuffer&) {
291 return SkShader::MakeEmptyShader();
292 }
293
294 #ifndef SK_IGNORE_TO_STRING
295 #include "SkEmptyShader.h"
296
toString(SkString * str) const297 void SkEmptyShader::toString(SkString* str) const {
298 str->append("SkEmptyShader: (");
299
300 this->INHERITED::toString(str);
301
302 str->append(")");
303 }
304 #endif
305