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      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 "SkBitmapProcShader.h"
      9 #include "SkEmptyShader.h"
     10 #include "SkReadBuffer.h"
     11 #include "SkMallocPixelRef.h"
     12 #include "SkPaint.h"
     13 #include "SkPicture.h"
     14 #include "SkPictureShader.h"
     15 #include "SkScalar.h"
     16 #include "SkShader.h"
     17 #include "SkThread.h"
     18 #include "SkWriteBuffer.h"
     19 
     20 //#define SK_TRACK_SHADER_LIFETIME
     21 
     22 #ifdef SK_TRACK_SHADER_LIFETIME
     23     static int32_t gShaderCounter;
     24 #endif
     25 
     26 static inline void inc_shader_counter() {
     27 #ifdef SK_TRACK_SHADER_LIFETIME
     28     int32_t prev = sk_atomic_inc(&gShaderCounter);
     29     SkDebugf("+++ shader counter %d\n", prev + 1);
     30 #endif
     31 }
     32 static inline void dec_shader_counter() {
     33 #ifdef SK_TRACK_SHADER_LIFETIME
     34     int32_t prev = sk_atomic_dec(&gShaderCounter);
     35     SkDebugf("--- shader counter %d\n", prev - 1);
     36 #endif
     37 }
     38 
     39 SkShader::SkShader(const SkMatrix* localMatrix) {
     40     inc_shader_counter();
     41     if (localMatrix) {
     42         fLocalMatrix = *localMatrix;
     43     } else {
     44         fLocalMatrix.reset();
     45     }
     46 #ifdef SK_BUILD_FOR_ANDROID_FRAMEWORK
     47     fGenerationID = 0;
     48 #endif
     49 }
     50 
     51 SkShader::SkShader(SkReadBuffer& buffer) : INHERITED(buffer) {
     52     inc_shader_counter();
     53     if (buffer.readBool()) {
     54         buffer.readMatrix(&fLocalMatrix);
     55     } else {
     56         fLocalMatrix.reset();
     57     }
     58 #ifdef SK_BUILD_FOR_ANDROID_FRAMEWORK
     59     fGenerationID = 0;
     60 #endif
     61 }
     62 
     63 SkShader::~SkShader() {
     64     dec_shader_counter();
     65 }
     66 
     67 void SkShader::flatten(SkWriteBuffer& buffer) const {
     68     this->INHERITED::flatten(buffer);
     69     bool hasLocalM = !fLocalMatrix.isIdentity();
     70     buffer.writeBool(hasLocalM);
     71     if (hasLocalM) {
     72         buffer.writeMatrix(fLocalMatrix);
     73     }
     74 }
     75 
     76 bool SkShader::computeTotalInverse(const ContextRec& rec, SkMatrix* totalInverse) const {
     77     SkMatrix total;
     78     total.setConcat(*rec.fMatrix, fLocalMatrix);
     79 
     80     const SkMatrix* m = &total;
     81     if (rec.fLocalMatrix) {
     82         total.setConcat(*m, *rec.fLocalMatrix);
     83         m = &total;
     84     }
     85     return m->invert(totalInverse);
     86 }
     87 
     88 SkShader::Context* SkShader::createContext(const ContextRec& rec, void* storage) const {
     89     if (!this->computeTotalInverse(rec, NULL)) {
     90         return NULL;
     91     }
     92     return this->onCreateContext(rec, storage);
     93 }
     94 
     95 SkShader::Context* SkShader::onCreateContext(const ContextRec& rec, void*) const {
     96     return NULL;
     97 }
     98 
     99 size_t SkShader::contextSize() const {
    100     return 0;
    101 }
    102 
    103 SkShader::Context::Context(const SkShader& shader, const ContextRec& rec)
    104     : fShader(shader), fCTM(*rec.fMatrix)
    105 {
    106     // Because the context parameters must be valid at this point, we know that the matrix is
    107     // invertible.
    108     SkAssertResult(fShader.computeTotalInverse(rec, &fTotalInverse));
    109     fTotalInverseClass = (uint8_t)ComputeMatrixClass(fTotalInverse);
    110 
    111     fPaintAlpha = rec.fPaint->getAlpha();
    112 }
    113 
    114 SkShader::Context::~Context() {}
    115 
    116 SkShader::Context::ShadeProc SkShader::Context::asAShadeProc(void** ctx) {
    117     return NULL;
    118 }
    119 
    120 #include "SkColorPriv.h"
    121 
    122 void SkShader::Context::shadeSpan16(int x, int y, uint16_t span16[], int count) {
    123     SkASSERT(span16);
    124     SkASSERT(count > 0);
    125     SkASSERT(this->canCallShadeSpan16());
    126 
    127     // basically, if we get here, the subclass screwed up
    128     SkDEBUGFAIL("kHasSpan16 flag is set, but shadeSpan16() not implemented");
    129 }
    130 
    131 #define kTempColorQuadCount 6   // balance between speed (larger) and saving stack-space
    132 #define kTempColorCount     (kTempColorQuadCount << 2)
    133 
    134 #ifdef SK_CPU_BENDIAN
    135     #define SkU32BitShiftToByteOffset(shift)    (3 - ((shift) >> 3))
    136 #else
    137     #define SkU32BitShiftToByteOffset(shift)    ((shift) >> 3)
    138 #endif
    139 
    140 void SkShader::Context::shadeSpanAlpha(int x, int y, uint8_t alpha[], int count) {
    141     SkASSERT(count > 0);
    142 
    143     SkPMColor   colors[kTempColorCount];
    144 
    145     while ((count -= kTempColorCount) >= 0) {
    146         this->shadeSpan(x, y, colors, kTempColorCount);
    147         x += kTempColorCount;
    148 
    149         const uint8_t* srcA = (const uint8_t*)colors + SkU32BitShiftToByteOffset(SK_A32_SHIFT);
    150         int quads = kTempColorQuadCount;
    151         do {
    152             U8CPU a0 = srcA[0];
    153             U8CPU a1 = srcA[4];
    154             U8CPU a2 = srcA[8];
    155             U8CPU a3 = srcA[12];
    156             srcA += 4*4;
    157             *alpha++ = SkToU8(a0);
    158             *alpha++ = SkToU8(a1);
    159             *alpha++ = SkToU8(a2);
    160             *alpha++ = SkToU8(a3);
    161         } while (--quads != 0);
    162     }
    163     SkASSERT(count < 0);
    164     SkASSERT(count + kTempColorCount >= 0);
    165     if (count += kTempColorCount) {
    166         this->shadeSpan(x, y, colors, count);
    167 
    168         const uint8_t* srcA = (const uint8_t*)colors + SkU32BitShiftToByteOffset(SK_A32_SHIFT);
    169         do {
    170             *alpha++ = *srcA;
    171             srcA += 4;
    172         } while (--count != 0);
    173     }
    174 #if 0
    175     do {
    176         int n = count;
    177         if (n > kTempColorCount)
    178             n = kTempColorCount;
    179         SkASSERT(n > 0);
    180 
    181         this->shadeSpan(x, y, colors, n);
    182         x += n;
    183         count -= n;
    184 
    185         const uint8_t* srcA = (const uint8_t*)colors + SkU32BitShiftToByteOffset(SK_A32_SHIFT);
    186         do {
    187             *alpha++ = *srcA;
    188             srcA += 4;
    189         } while (--n != 0);
    190     } while (count > 0);
    191 #endif
    192 }
    193 
    194 SkShader::Context::MatrixClass SkShader::Context::ComputeMatrixClass(const SkMatrix& mat) {
    195     MatrixClass mc = kLinear_MatrixClass;
    196 
    197     if (mat.hasPerspective()) {
    198         if (mat.fixedStepInX(0, NULL, NULL)) {
    199             mc = kFixedStepInX_MatrixClass;
    200         } else {
    201             mc = kPerspective_MatrixClass;
    202         }
    203     }
    204     return mc;
    205 }
    206 
    207 //////////////////////////////////////////////////////////////////////////////
    208 
    209 SkShader::BitmapType SkShader::asABitmap(SkBitmap*, SkMatrix*, TileMode*) const {
    210     return kNone_BitmapType;
    211 }
    212 
    213 SkShader::GradientType SkShader::asAGradient(GradientInfo* info) const {
    214     return kNone_GradientType;
    215 }
    216 
    217 bool SkShader::asNewEffect(GrContext* context, const SkPaint& paint,
    218                            const SkMatrix* localMatrixOrNull, GrColor* grColor,
    219                            GrEffectRef** grEffect)  const {
    220     return false;
    221 }
    222 
    223 SkShader* SkShader::refAsALocalMatrixShader(SkMatrix*) const {
    224     return NULL;
    225 }
    226 
    227 SkShader* SkShader::CreateEmptyShader() {
    228     return SkNEW(SkEmptyShader);
    229 }
    230 
    231 SkShader* SkShader::CreateBitmapShader(const SkBitmap& src, TileMode tmx, TileMode tmy,
    232                                        const SkMatrix* localMatrix) {
    233     return ::CreateBitmapShader(src, tmx, tmy, localMatrix, NULL);
    234 }
    235 
    236 SkShader* SkShader::CreatePictureShader(SkPicture* src, TileMode tmx, TileMode tmy,
    237                                        const SkMatrix* localMatrix) {
    238     return SkPictureShader::Create(src, tmx, tmy, localMatrix);
    239 }
    240 
    241 #ifndef SK_IGNORE_TO_STRING
    242 void SkShader::toString(SkString* str) const {
    243     if (!fLocalMatrix.isIdentity()) {
    244         str->append(" ");
    245         fLocalMatrix.toString(str);
    246     }
    247 }
    248 #endif
    249 
    250 //////////////////////////////////////////////////////////////////////////////
    251 
    252 #include "SkColorShader.h"
    253 #include "SkUtils.h"
    254 
    255 SkColorShader::SkColorShader(SkColor c)
    256     : fColor(c) {
    257 }
    258 
    259 bool SkColorShader::isOpaque() const {
    260     return SkColorGetA(fColor) == 255;
    261 }
    262 
    263 SkColorShader::SkColorShader(SkReadBuffer& b) : INHERITED(b) {
    264     // V25_COMPATIBILITY_CODE We had a boolean to make the color shader inherit the paint's
    265     // color. We don't support that any more.
    266     if (b.isVersionLT(SkReadBuffer::kColorShaderNoBool_Version)) {
    267         if (b.readBool()) {
    268             SkDEBUGFAIL("We shouldn't have pictures that recorded the inherited case.");
    269             fColor = SK_ColorWHITE;
    270             return;
    271         }
    272     }
    273     fColor = b.readColor();
    274 }
    275 
    276 void SkColorShader::flatten(SkWriteBuffer& buffer) const {
    277     this->INHERITED::flatten(buffer);
    278     buffer.writeColor(fColor);
    279 }
    280 
    281 uint32_t SkColorShader::ColorShaderContext::getFlags() const {
    282     return fFlags;
    283 }
    284 
    285 uint8_t SkColorShader::ColorShaderContext::getSpan16Alpha() const {
    286     return SkGetPackedA32(fPMColor);
    287 }
    288 
    289 SkShader::Context* SkColorShader::onCreateContext(const ContextRec& rec, void* storage) const {
    290     return SkNEW_PLACEMENT_ARGS(storage, ColorShaderContext, (*this, rec));
    291 }
    292 
    293 SkColorShader::ColorShaderContext::ColorShaderContext(const SkColorShader& shader,
    294                                                       const ContextRec& rec)
    295     : INHERITED(shader, rec)
    296 {
    297     SkColor color = shader.fColor;
    298     unsigned a = SkAlphaMul(SkColorGetA(color), SkAlpha255To256(rec.fPaint->getAlpha()));
    299 
    300     unsigned r = SkColorGetR(color);
    301     unsigned g = SkColorGetG(color);
    302     unsigned b = SkColorGetB(color);
    303 
    304     // we want this before we apply any alpha
    305     fColor16 = SkPack888ToRGB16(r, g, b);
    306 
    307     if (a != 255) {
    308         r = SkMulDiv255Round(r, a);
    309         g = SkMulDiv255Round(g, a);
    310         b = SkMulDiv255Round(b, a);
    311     }
    312     fPMColor = SkPackARGB32(a, r, g, b);
    313 
    314     fFlags = kConstInY32_Flag;
    315     if (255 == a) {
    316         fFlags |= kOpaqueAlpha_Flag;
    317         if (rec.fPaint->isDither() == false) {
    318             fFlags |= kHasSpan16_Flag;
    319         }
    320     }
    321 }
    322 
    323 void SkColorShader::ColorShaderContext::shadeSpan(int x, int y, SkPMColor span[], int count) {
    324     sk_memset32(span, fPMColor, count);
    325 }
    326 
    327 void SkColorShader::ColorShaderContext::shadeSpan16(int x, int y, uint16_t span[], int count) {
    328     sk_memset16(span, fColor16, count);
    329 }
    330 
    331 void SkColorShader::ColorShaderContext::shadeSpanAlpha(int x, int y, uint8_t alpha[], int count) {
    332     memset(alpha, SkGetPackedA32(fPMColor), count);
    333 }
    334 
    335 // if we had a asAColor method, that would be more efficient...
    336 SkShader::BitmapType SkColorShader::asABitmap(SkBitmap* bitmap, SkMatrix* matrix,
    337                                               TileMode modes[]) const {
    338     return kNone_BitmapType;
    339 }
    340 
    341 SkShader::GradientType SkColorShader::asAGradient(GradientInfo* info) const {
    342     if (info) {
    343         if (info->fColors && info->fColorCount >= 1) {
    344             info->fColors[0] = fColor;
    345         }
    346         info->fColorCount = 1;
    347         info->fTileMode = SkShader::kRepeat_TileMode;
    348     }
    349     return kColor_GradientType;
    350 }
    351 
    352 #if SK_SUPPORT_GPU
    353 
    354 #include "SkGr.h"
    355 
    356 bool SkColorShader::asNewEffect(GrContext* context, const SkPaint& paint,
    357                                 const SkMatrix* localMatrix, GrColor* grColor,
    358                                 GrEffectRef** grEffect) const {
    359     *grEffect = NULL;
    360     SkColor skColor = fColor;
    361     U8CPU newA = SkMulDiv255Round(SkColorGetA(fColor), paint.getAlpha());
    362     *grColor = SkColor2GrColor(SkColorSetA(skColor, newA));
    363     return true;
    364 }
    365 
    366 #else
    367 
    368 bool SkColorShader::asNewEffect(GrContext* context, const SkPaint& paint,
    369                                      const SkMatrix* localMatrix, GrColor* grColor,
    370                                      GrEffectRef** grEffect) const {
    371     SkDEBUGFAIL("Should not call in GPU-less build");
    372     return false;
    373 }
    374 
    375 #endif
    376 
    377 #ifndef SK_IGNORE_TO_STRING
    378 void SkColorShader::toString(SkString* str) const {
    379     str->append("SkColorShader: (");
    380 
    381     str->append("Color: ");
    382     str->appendHex(fColor);
    383 
    384     this->INHERITED::toString(str);
    385 
    386     str->append(")");
    387 }
    388 #endif
    389 
    390 ///////////////////////////////////////////////////////////////////////////////
    391 
    392 #ifndef SK_IGNORE_TO_STRING
    393 #include "SkEmptyShader.h"
    394 
    395 void SkEmptyShader::toString(SkString* str) const {
    396     str->append("SkEmptyShader: (");
    397 
    398     this->INHERITED::toString(str);
    399 
    400     str->append(")");
    401 }
    402 #endif
    403