1 /*
2 * Copyright 2021 Google LLC
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/core/SkBlendModeBlender.h"
9
10 #include "include/core/SkBlendMode.h"
11 #include "include/core/SkBlender.h"
12 #include "include/core/SkRefCnt.h"
13 #include "include/private/base/SkAssert.h"
14 #include "src/base/SkNoDestructor.h"
15 #include "src/core/SkBlendModePriv.h"
16 #include "src/core/SkEffectPriv.h"
17 #include "src/core/SkReadBuffer.h"
18 #include "src/core/SkWriteBuffer.h"
19
Mode(SkBlendMode mode)20 sk_sp<SkBlender> SkBlender::Mode(SkBlendMode mode) {
21 #define RETURN_SINGLETON_BLENDER(m) \
22 case m: { \
23 static SkNoDestructor<SkBlendModeBlender> sBlender(m); \
24 return sk_ref_sp(sBlender.get()); \
25 }
26
27 switch (mode) {
28 RETURN_SINGLETON_BLENDER(SkBlendMode::kClear)
29 RETURN_SINGLETON_BLENDER(SkBlendMode::kSrc)
30 RETURN_SINGLETON_BLENDER(SkBlendMode::kDst)
31 RETURN_SINGLETON_BLENDER(SkBlendMode::kSrcOver)
32 RETURN_SINGLETON_BLENDER(SkBlendMode::kDstOver)
33 RETURN_SINGLETON_BLENDER(SkBlendMode::kSrcIn)
34 RETURN_SINGLETON_BLENDER(SkBlendMode::kDstIn)
35 RETURN_SINGLETON_BLENDER(SkBlendMode::kSrcOut)
36 RETURN_SINGLETON_BLENDER(SkBlendMode::kDstOut)
37 RETURN_SINGLETON_BLENDER(SkBlendMode::kSrcATop)
38 RETURN_SINGLETON_BLENDER(SkBlendMode::kDstATop)
39 RETURN_SINGLETON_BLENDER(SkBlendMode::kXor)
40 RETURN_SINGLETON_BLENDER(SkBlendMode::kPlus)
41 RETURN_SINGLETON_BLENDER(SkBlendMode::kModulate)
42 RETURN_SINGLETON_BLENDER(SkBlendMode::kScreen)
43 RETURN_SINGLETON_BLENDER(SkBlendMode::kOverlay)
44 RETURN_SINGLETON_BLENDER(SkBlendMode::kDarken)
45 RETURN_SINGLETON_BLENDER(SkBlendMode::kLighten)
46 RETURN_SINGLETON_BLENDER(SkBlendMode::kColorDodge)
47 RETURN_SINGLETON_BLENDER(SkBlendMode::kColorBurn)
48 RETURN_SINGLETON_BLENDER(SkBlendMode::kHardLight)
49 RETURN_SINGLETON_BLENDER(SkBlendMode::kSoftLight)
50 RETURN_SINGLETON_BLENDER(SkBlendMode::kDifference)
51 RETURN_SINGLETON_BLENDER(SkBlendMode::kExclusion)
52 RETURN_SINGLETON_BLENDER(SkBlendMode::kMultiply)
53 RETURN_SINGLETON_BLENDER(SkBlendMode::kHue)
54 RETURN_SINGLETON_BLENDER(SkBlendMode::kSaturation)
55 RETURN_SINGLETON_BLENDER(SkBlendMode::kColor)
56 RETURN_SINGLETON_BLENDER(SkBlendMode::kLuminosity)
57 }
58
59 SkDEBUGFAILF("invalid blend mode %d", (int)mode);
60 return nullptr;
61
62 #undef RETURN_SINGLETON_BLENDER
63 }
64
CreateProc(SkReadBuffer & buffer)65 sk_sp<SkFlattenable> SkBlendModeBlender::CreateProc(SkReadBuffer& buffer) {
66 SkBlendMode mode = buffer.read32LE(SkBlendMode::kLastMode);
67 return SkBlender::Mode(mode);
68 }
69
flatten(SkWriteBuffer & buffer) const70 void SkBlendModeBlender::flatten(SkWriteBuffer& buffer) const {
71 buffer.writeInt((int)fMode);
72 }
73
onAppendStages(const SkStageRec & rec) const74 bool SkBlendModeBlender::onAppendStages(const SkStageRec& rec) const {
75 SkBlendMode_AppendStages(fMode, rec.fPipeline);
76 return true;
77 }
78
affectsTransparentBlack() const79 bool SkBlenderBase::affectsTransparentBlack() const {
80 if (auto blendMode = this->asBlendMode()) {
81 SkBlendModeCoeff src, dst;
82 if (SkBlendMode_AsCoeff(*blendMode, &src, &dst)) {
83 // If the source is (0,0,0,0), then dst is preserved as long as its coefficient
84 // evaluates to 1.0. This is true for kOne, kISA, and kISC. Anything else means the
85 // blend mode affects transparent black.
86 return dst != SkBlendModeCoeff::kOne &&
87 dst != SkBlendModeCoeff::kISA &&
88 dst != SkBlendModeCoeff::kISC;
89 } else {
90 // An advanced blend mode, which do not affect transparent black
91 return false;
92 }
93 } else {
94 // Blenders that aren't blend modes are assumed to modify transparent black.
95 return true;
96 }
97 }
98