1 | /* |
2 | * Copyright 2013 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 "include/effects/SkAlphaThresholdFilter.h" |
9 | |
10 | #include "include/core/SkBitmap.h" |
11 | #include "include/core/SkRegion.h" |
12 | #include "src/core/SkImageFilter_Base.h" |
13 | #include "src/core/SkReadBuffer.h" |
14 | #include "src/core/SkSpecialImage.h" |
15 | #include "src/core/SkWriteBuffer.h" |
16 | |
17 | #if SK_SUPPORT_GPU |
18 | #include "include/gpu/GrContext.h" |
19 | #include "include/private/GrRecordingContext.h" |
20 | #include "src/gpu/GrCaps.h" |
21 | #include "src/gpu/GrColorSpaceXform.h" |
22 | #include "src/gpu/GrFixedClip.h" |
23 | #include "src/gpu/GrRecordingContextPriv.h" |
24 | #include "src/gpu/GrRenderTargetContext.h" |
25 | #include "src/gpu/GrTextureProxy.h" |
26 | #include "src/gpu/effects/GrTextureEffect.h" |
27 | #include "src/gpu/effects/generated/GrAlphaThresholdFragmentProcessor.h" |
28 | #endif |
29 | |
30 | namespace { |
31 | |
32 | class SkAlphaThresholdFilterImpl final : public SkImageFilter_Base { |
33 | public: |
34 | SkAlphaThresholdFilterImpl(const SkRegion& region, SkScalar innerThreshold, |
35 | SkScalar outerThreshold, sk_sp<SkImageFilter> input, |
36 | const CropRect* cropRect = nullptr) |
37 | : INHERITED(&input, 1, cropRect) |
38 | , fRegion(region) |
39 | , fInnerThreshold(innerThreshold) |
40 | , fOuterThreshold(outerThreshold) {} |
41 | |
42 | protected: |
43 | void flatten(SkWriteBuffer&) const override; |
44 | |
45 | sk_sp<SkSpecialImage> onFilterImage(const Context&, SkIPoint* offset) const override; |
46 | |
47 | #if SK_SUPPORT_GPU |
48 | GrSurfaceProxyView createMaskTexture(GrRecordingContext*, |
49 | const SkMatrix&, |
50 | const SkIRect& bounds) const; |
51 | #endif |
52 | |
53 | private: |
54 | friend void SkAlphaThresholdFilter::RegisterFlattenables(); |
55 | SK_FLATTENABLE_HOOKS(SkAlphaThresholdFilterImpl) |
56 | |
57 | SkRegion fRegion; |
58 | SkScalar fInnerThreshold; |
59 | SkScalar fOuterThreshold; |
60 | |
61 | typedef SkImageFilter_Base INHERITED; |
62 | }; |
63 | |
64 | }; // end namespace |
65 | |
66 | sk_sp<SkImageFilter> SkAlphaThresholdFilter::Make(const SkRegion& region, SkScalar innerThreshold, |
67 | SkScalar outerThreshold, |
68 | sk_sp<SkImageFilter> input, |
69 | const SkImageFilter::CropRect* cropRect) { |
70 | innerThreshold = SkTPin(innerThreshold, 0.f, 1.f); |
71 | outerThreshold = SkTPin(outerThreshold, 0.f, 1.f); |
72 | if (!SkScalarIsFinite(innerThreshold) || !SkScalarIsFinite(outerThreshold)) { |
73 | return nullptr; |
74 | } |
75 | return sk_sp<SkImageFilter>(new SkAlphaThresholdFilterImpl( |
76 | region, innerThreshold, outerThreshold, std::move(input), cropRect)); |
77 | } |
78 | |
79 | void SkAlphaThresholdFilter::RegisterFlattenables() { |
80 | SK_REGISTER_FLATTENABLE(SkAlphaThresholdFilterImpl); |
81 | } |
82 | |
83 | /////////////////////////////////////////////////////////////////////////////////////////////////// |
84 | |
85 | sk_sp<SkFlattenable> SkAlphaThresholdFilterImpl::CreateProc(SkReadBuffer& buffer) { |
86 | SK_IMAGEFILTER_UNFLATTEN_COMMON(common, 1); |
87 | SkScalar inner = buffer.readScalar(); |
88 | SkScalar outer = buffer.readScalar(); |
89 | SkRegion rgn; |
90 | buffer.readRegion(&rgn); |
91 | return SkAlphaThresholdFilter::Make(rgn, inner, outer, common.getInput(0), |
92 | &common.cropRect()); |
93 | } |
94 | |
95 | void SkAlphaThresholdFilterImpl::flatten(SkWriteBuffer& buffer) const { |
96 | this->INHERITED::flatten(buffer); |
97 | buffer.writeScalar(fInnerThreshold); |
98 | buffer.writeScalar(fOuterThreshold); |
99 | buffer.writeRegion(fRegion); |
100 | } |
101 | |
102 | #if SK_SUPPORT_GPU |
103 | GrSurfaceProxyView SkAlphaThresholdFilterImpl::createMaskTexture(GrRecordingContext* context, |
104 | const SkMatrix& inMatrix, |
105 | const SkIRect& bounds) const { |
106 | auto rtContext = GrRenderTargetContext::MakeWithFallback( |
107 | context, GrColorType::kAlpha_8, nullptr, SkBackingFit::kApprox, bounds.size()); |
108 | if (!rtContext) { |
109 | return {}; |
110 | } |
111 | |
112 | SkRegion::Iterator iter(fRegion); |
113 | rtContext->clear(nullptr, SK_PMColor4fTRANSPARENT, |
114 | GrRenderTargetContext::CanClearFullscreen::kYes); |
115 | |
116 | GrFixedClip clip(SkIRect::MakeWH(bounds.width(), bounds.height())); |
117 | while (!iter.done()) { |
118 | GrPaint paint; |
119 | paint.setPorterDuffXPFactory(SkBlendMode::kSrc); |
120 | |
121 | SkRect rect = SkRect::Make(iter.rect()); |
122 | |
123 | rtContext->drawRect(clip, std::move(paint), GrAA::kNo, inMatrix, rect); |
124 | |
125 | iter.next(); |
126 | } |
127 | |
128 | return rtContext->readSurfaceView(); |
129 | } |
130 | #endif |
131 | |
132 | sk_sp<SkSpecialImage> SkAlphaThresholdFilterImpl::onFilterImage(const Context& ctx, |
133 | SkIPoint* offset) const { |
134 | SkIPoint inputOffset = SkIPoint::Make(0, 0); |
135 | sk_sp<SkSpecialImage> input(this->filterInput(0, ctx, &inputOffset)); |
136 | if (!input) { |
137 | return nullptr; |
138 | } |
139 | |
140 | const SkIRect inputBounds = SkIRect::MakeXYWH(inputOffset.x(), inputOffset.y(), |
141 | input->width(), input->height()); |
142 | |
143 | SkIRect bounds; |
144 | if (!this->applyCropRect(ctx, inputBounds, &bounds)) { |
145 | return nullptr; |
146 | } |
147 | |
148 | #if SK_SUPPORT_GPU |
149 | if (ctx.gpuBacked()) { |
150 | auto context = ctx.getContext(); |
151 | |
152 | GrSurfaceProxyView inputView = (input->view(context)); |
153 | SkASSERT(inputView.asTextureProxy()); |
154 | const GrProtected isProtected = inputView.proxy()->isProtected(); |
155 | |
156 | offset->fX = bounds.left(); |
157 | offset->fY = bounds.top(); |
158 | |
159 | bounds.offset(-inputOffset); |
160 | |
161 | SkMatrix matrix(ctx.ctm()); |
162 | matrix.postTranslate(SkIntToScalar(-offset->fX), SkIntToScalar(-offset->fY)); |
163 | |
164 | GrSurfaceProxyView maskView = this->createMaskTexture(context, matrix, bounds); |
165 | if (!maskView) { |
166 | return nullptr; |
167 | } |
168 | |
169 | auto textureFP = GrTextureEffect::Make( |
170 | std::move(inputView), input->alphaType(), |
171 | SkMatrix::MakeTrans(input->subset().x(), input->subset().y())); |
172 | textureFP = GrColorSpaceXformEffect::Make(std::move(textureFP), input->getColorSpace(), |
173 | input->alphaType(), ctx.colorSpace()); |
174 | if (!textureFP) { |
175 | return nullptr; |
176 | } |
177 | |
178 | auto thresholdFP = GrAlphaThresholdFragmentProcessor::Make( |
179 | std::move(maskView), fInnerThreshold, fOuterThreshold, bounds); |
180 | if (!thresholdFP) { |
181 | return nullptr; |
182 | } |
183 | |
184 | std::unique_ptr<GrFragmentProcessor> fpSeries[] = { std::move(textureFP), |
185 | std::move(thresholdFP) }; |
186 | auto fp = GrFragmentProcessor::RunInSeries(fpSeries, 2); |
187 | |
188 | return DrawWithFP(context, std::move(fp), bounds, ctx.colorType(), ctx.colorSpace(), |
189 | isProtected); |
190 | } |
191 | #endif |
192 | |
193 | SkBitmap inputBM; |
194 | |
195 | if (!input->getROPixels(&inputBM)) { |
196 | return nullptr; |
197 | } |
198 | |
199 | if (inputBM.colorType() != kN32_SkColorType) { |
200 | return nullptr; |
201 | } |
202 | |
203 | if (!inputBM.getPixels() || inputBM.width() <= 0 || inputBM.height() <= 0) { |
204 | return nullptr; |
205 | } |
206 | |
207 | |
208 | SkMatrix localInverse; |
209 | if (!ctx.ctm().invert(&localInverse)) { |
210 | return nullptr; |
211 | } |
212 | |
213 | SkImageInfo info = SkImageInfo::MakeN32(bounds.width(), bounds.height(), |
214 | kPremul_SkAlphaType); |
215 | |
216 | SkBitmap dst; |
217 | if (!dst.tryAllocPixels(info)) { |
218 | return nullptr; |
219 | } |
220 | |
221 | U8CPU innerThreshold = (U8CPU)(fInnerThreshold * 0xFF); |
222 | U8CPU outerThreshold = (U8CPU)(fOuterThreshold * 0xFF); |
223 | SkColor* dptr = dst.getAddr32(0, 0); |
224 | int dstWidth = dst.width(), dstHeight = dst.height(); |
225 | SkIPoint srcOffset = { bounds.fLeft - inputOffset.fX, bounds.fTop - inputOffset.fY }; |
226 | for (int y = 0; y < dstHeight; ++y) { |
227 | const SkColor* sptr = inputBM.getAddr32(srcOffset.fX, srcOffset.fY+y); |
228 | |
229 | for (int x = 0; x < dstWidth; ++x) { |
230 | const SkColor& source = sptr[x]; |
231 | SkColor outputColor(source); |
232 | SkPoint position; |
233 | localInverse.mapXY((SkScalar)x + bounds.fLeft, (SkScalar)y + bounds.fTop, &position); |
234 | if (fRegion.contains((int32_t)position.x(), (int32_t)position.y())) { |
235 | if (SkColorGetA(source) < innerThreshold) { |
236 | U8CPU alpha = SkColorGetA(source); |
237 | if (alpha == 0) { |
238 | alpha = 1; |
239 | } |
240 | float scale = (float)innerThreshold / alpha; |
241 | outputColor = SkColorSetARGB(innerThreshold, |
242 | (U8CPU)(SkColorGetR(source) * scale), |
243 | (U8CPU)(SkColorGetG(source) * scale), |
244 | (U8CPU)(SkColorGetB(source) * scale)); |
245 | } |
246 | } else { |
247 | if (SkColorGetA(source) > outerThreshold) { |
248 | float scale = (float)outerThreshold / SkColorGetA(source); |
249 | outputColor = SkColorSetARGB(outerThreshold, |
250 | (U8CPU)(SkColorGetR(source) * scale), |
251 | (U8CPU)(SkColorGetG(source) * scale), |
252 | (U8CPU)(SkColorGetB(source) * scale)); |
253 | } |
254 | } |
255 | dptr[y * dstWidth + x] = outputColor; |
256 | } |
257 | } |
258 | |
259 | offset->fX = bounds.left(); |
260 | offset->fY = bounds.top(); |
261 | return SkSpecialImage::MakeFromRaster(SkIRect::MakeWH(bounds.width(), bounds.height()), |
262 | dst); |
263 | } |
264 | |