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 "src/shaders/SkBitmapProcShader.h"
9
10 #include "src/core/SkArenaAlloc.h"
11 #include "src/core/SkBitmapProcState.h"
12 #include "src/core/SkPaintPriv.h"
13 #include "src/core/SkXfermodePriv.h"
14
15 class BitmapProcShaderContext : public SkShaderBase::Context {
16 public:
BitmapProcShaderContext(const SkShaderBase & shader,const SkShaderBase::ContextRec & rec,SkBitmapProcState * state)17 BitmapProcShaderContext(const SkShaderBase& shader, const SkShaderBase::ContextRec& rec,
18 SkBitmapProcState* state)
19 : INHERITED(shader, rec)
20 , fState(state)
21 , fFlags(0)
22 {
23 if (fState->fPixmap.isOpaque() && (255 == this->getPaintAlpha())) {
24 fFlags |= SkShaderBase::kOpaqueAlpha_Flag;
25 }
26
27 auto only_scale_and_translate = [](const SkMatrix& matrix) {
28 unsigned mask = SkMatrix::kTranslate_Mask | SkMatrix::kScale_Mask;
29 return (matrix.getType() & ~mask) == 0;
30 };
31
32 if (1 == fState->fPixmap.height() && only_scale_and_translate(this->getTotalInverse())) {
33 fFlags |= SkShaderBase::kConstInY32_Flag;
34 }
35 }
36
getFlags() const37 uint32_t getFlags() const override { return fFlags; }
38
shadeSpan(int x,int y,SkPMColor dstC[],int count)39 void shadeSpan(int x, int y, SkPMColor dstC[], int count) override {
40 const SkBitmapProcState& state = *fState;
41 if (state.getShaderProc32()) {
42 state.getShaderProc32()(&state, x, y, dstC, count);
43 return;
44 }
45
46 const int BUF_MAX = 128;
47 uint32_t buffer[BUF_MAX];
48 SkBitmapProcState::MatrixProc mproc = state.getMatrixProc();
49 SkBitmapProcState::SampleProc32 sproc = state.getSampleProc32();
50 const int max = state.maxCountForBufferSize(sizeof(buffer[0]) * BUF_MAX);
51
52 SkASSERT(state.fPixmap.addr());
53
54 for (;;) {
55 int n = std::min(count, max);
56 SkASSERT(n > 0 && n < BUF_MAX*2);
57 mproc(state, buffer, n, x, y);
58 sproc(state, buffer, n, dstC);
59
60 if ((count -= n) == 0) {
61 break;
62 }
63 SkASSERT(count > 0);
64 x += n;
65 dstC += n;
66 }
67 }
68
69 private:
70 SkBitmapProcState* fState;
71 uint32_t fFlags;
72
73 using INHERITED = SkShaderBase::Context;
74 };
75
76 ///////////////////////////////////////////////////////////////////////////////////////////////////
77
MakeContext(const SkShaderBase & shader,SkTileMode tmx,SkTileMode tmy,const SkSamplingOptions & sampling,const SkImage_Base * image,const ContextRec & rec,SkArenaAlloc * alloc)78 SkShaderBase::Context* SkBitmapProcLegacyShader::MakeContext(
79 const SkShaderBase& shader, SkTileMode tmx, SkTileMode tmy, const SkSamplingOptions& sampling,
80 const SkImage_Base* image, const ContextRec& rec, SkArenaAlloc* alloc)
81 {
82 SkMatrix totalInverse;
83 // Do this first, so we know the matrix can be inverted.
84 if (!shader.computeTotalInverse(*rec.fMatrix, rec.fLocalMatrix, &totalInverse)) {
85 return nullptr;
86 }
87
88 SkBitmapProcState* state = alloc->make<SkBitmapProcState>(image, tmx, tmy);
89 if (!state->setup(totalInverse, rec.fPaintAlpha, sampling)) {
90 return nullptr;
91 }
92 return alloc->make<BitmapProcShaderContext>(shader, rec, state);
93 }
94