1 /*
2 * Copyright 2012 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 "SkMergeImageFilter.h"
9
10 #include "SkCanvas.h"
11 #include "SkReadBuffer.h"
12 #include "SkSpecialImage.h"
13 #include "SkSpecialSurface.h"
14 #include "SkWriteBuffer.h"
15 #include "SkValidationUtils.h"
16
Make(sk_sp<SkImageFilter> first,sk_sp<SkImageFilter> second,SkBlendMode mode,const CropRect * cropRect)17 sk_sp<SkImageFilter> SkMergeImageFilter::Make(sk_sp<SkImageFilter> first,
18 sk_sp<SkImageFilter> second,
19 SkBlendMode mode,
20 const CropRect* cropRect) {
21 sk_sp<SkImageFilter> inputs[2] = { first, second };
22 SkBlendMode modes[2] = { mode, mode };
23 return sk_sp<SkImageFilter>(new SkMergeImageFilter(inputs, 2, modes, cropRect));
24 }
25
MakeN(sk_sp<SkImageFilter> filters[],int count,const SkBlendMode modes[],const CropRect * cropRect)26 sk_sp<SkImageFilter> SkMergeImageFilter::MakeN(sk_sp<SkImageFilter> filters[], int count,
27 const SkBlendMode modes[],
28 const CropRect* cropRect) {
29 return sk_sp<SkImageFilter>(new SkMergeImageFilter(filters, count, modes, cropRect));
30 }
31
32 ///////////////////////////////////////////////////////////////////////////////
33
initAllocModes()34 void SkMergeImageFilter::initAllocModes() {
35 int inputCount = this->countInputs();
36 if (inputCount) {
37 size_t size = sizeof(uint8_t) * inputCount;
38 if (size <= sizeof(fStorage)) {
39 fModes = SkTCast<uint8_t*>(fStorage);
40 } else {
41 fModes = SkTCast<uint8_t*>(sk_malloc_throw(size));
42 }
43 } else {
44 fModes = nullptr;
45 }
46 }
47
initModes(const SkBlendMode modes[])48 void SkMergeImageFilter::initModes(const SkBlendMode modes[]) {
49 if (modes) {
50 this->initAllocModes();
51 int inputCount = this->countInputs();
52 for (int i = 0; i < inputCount; ++i) {
53 fModes[i] = SkToU8((unsigned)modes[i]);
54 }
55 } else {
56 fModes = nullptr;
57 }
58 }
59
SkMergeImageFilter(sk_sp<SkImageFilter> filters[],int count,const SkBlendMode modes[],const CropRect * cropRect)60 SkMergeImageFilter::SkMergeImageFilter(sk_sp<SkImageFilter> filters[], int count,
61 const SkBlendMode modes[],
62 const CropRect* cropRect)
63 : INHERITED(filters, count, cropRect) {
64 SkASSERT(count >= 0);
65 this->initModes(modes);
66 }
67
~SkMergeImageFilter()68 SkMergeImageFilter::~SkMergeImageFilter() {
69
70 if (fModes != SkTCast<uint8_t*>(fStorage)) {
71 sk_free(fModes);
72 }
73 }
74
onFilterImage(SkSpecialImage * source,const Context & ctx,SkIPoint * offset) const75 sk_sp<SkSpecialImage> SkMergeImageFilter::onFilterImage(SkSpecialImage* source, const Context& ctx,
76 SkIPoint* offset) const {
77 int inputCount = this->countInputs();
78 if (inputCount < 1) {
79 return nullptr;
80 }
81
82 SkIRect bounds;
83 bounds.setEmpty();
84
85 std::unique_ptr<sk_sp<SkSpecialImage>[]> inputs(new sk_sp<SkSpecialImage>[inputCount]);
86 std::unique_ptr<SkIPoint[]> offsets(new SkIPoint[inputCount]);
87
88 // Filter all of the inputs.
89 for (int i = 0; i < inputCount; ++i) {
90 offsets[i].setZero();
91 inputs[i] = this->filterInput(i, source, ctx, &offsets[i]);
92 if (!inputs[i]) {
93 continue;
94 }
95 const SkIRect inputBounds = SkIRect::MakeXYWH(offsets[i].fX, offsets[i].fY,
96 inputs[i]->width(), inputs[i]->height());
97 bounds.join(inputBounds);
98 }
99 if (bounds.isEmpty()) {
100 return nullptr;
101 }
102
103 // Apply the crop rect to the union of the inputs' bounds.
104 // Note that the crop rect can only reduce the bounds, since this
105 // filter does not affect transparent black.
106 bool embiggen = false;
107 this->getCropRect().applyTo(bounds, ctx.ctm(), embiggen, &bounds);
108 if (!bounds.intersect(ctx.clipBounds())) {
109 return nullptr;
110 }
111
112 const int x0 = bounds.left();
113 const int y0 = bounds.top();
114
115 sk_sp<SkSpecialSurface> surf(source->makeSurface(ctx.outputProperties(), bounds.size()));
116 if (!surf) {
117 return nullptr;
118 }
119
120 SkCanvas* canvas = surf->getCanvas();
121 SkASSERT(canvas);
122
123 canvas->clear(0x0);
124
125 // Composite all of the filter inputs.
126 for (int i = 0; i < inputCount; ++i) {
127 if (!inputs[i]) {
128 continue;
129 }
130
131 SkPaint paint;
132 if (fModes) {
133 paint.setBlendMode((SkBlendMode)fModes[i]);
134 }
135
136 inputs[i]->draw(canvas,
137 SkIntToScalar(offsets[i].x() - x0), SkIntToScalar(offsets[i].y() - y0),
138 &paint);
139 }
140
141 offset->fX = bounds.left();
142 offset->fY = bounds.top();
143 return surf->makeImageSnapshot();
144 }
145
CreateProc(SkReadBuffer & buffer)146 sk_sp<SkFlattenable> SkMergeImageFilter::CreateProc(SkReadBuffer& buffer) {
147 Common common;
148 if (!common.unflatten(buffer, -1)) {
149 return nullptr;
150 }
151
152 const int count = common.inputCount();
153 bool hasModes = buffer.readBool();
154 if (hasModes) {
155 SkAutoSTArray<4, SkBlendMode> modes(count);
156 SkAutoSTArray<4, uint8_t> modes8(count);
157 if (!buffer.readByteArray(modes8.get(), count)) {
158 return nullptr;
159 }
160 for (int i = 0; i < count; ++i) {
161 modes[i] = (SkBlendMode)modes8[i];
162 buffer.validate(SkIsValidMode(modes[i]));
163 }
164 if (!buffer.isValid()) {
165 return nullptr;
166 }
167 return MakeN(common.inputs(), count, modes.get(), &common.cropRect());
168 }
169 return MakeN(common.inputs(), count, nullptr, &common.cropRect());
170 }
171
flatten(SkWriteBuffer & buffer) const172 void SkMergeImageFilter::flatten(SkWriteBuffer& buffer) const {
173 this->INHERITED::flatten(buffer);
174 buffer.writeBool(fModes != nullptr);
175 if (fModes) {
176 buffer.writeByteArray(fModes, this->countInputs() * sizeof(fModes[0]));
177 }
178 }
179
180 #ifndef SK_IGNORE_TO_STRING
toString(SkString * str) const181 void SkMergeImageFilter::toString(SkString* str) const {
182 str->appendf("SkMergeImageFilter: (");
183
184 for (int i = 0; i < this->countInputs(); ++i) {
185 SkImageFilter* filter = this->getInput(i);
186 str->appendf("%d: (", i);
187 filter->toString(str);
188 str->appendf(")");
189 }
190
191 str->append(")");
192 }
193 #endif
194