1 /*
2  * Copyright 2015 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 "gm/gm.h"
9 #include "include/core/SkBlendMode.h"
10 #include "include/core/SkCanvas.h"
11 #include "include/core/SkColor.h"
12 #include "include/core/SkColorFilter.h"
13 #include "include/core/SkFilterQuality.h"
14 #include "include/core/SkImage.h"
15 #include "include/core/SkImageFilter.h"
16 #include "include/core/SkImageInfo.h"
17 #include "include/core/SkMaskFilter.h"
18 #include "include/core/SkMatrix.h"
19 #include "include/core/SkPaint.h"
20 #include "include/core/SkRRect.h"
21 #include "include/core/SkRect.h"
22 #include "include/core/SkRefCnt.h"
23 #include "include/core/SkScalar.h"
24 #include "include/core/SkSurface.h"
25 #include "include/core/SkTypes.h"
26 #include "include/effects/SkColorMatrix.h"
27 #include "include/effects/SkGradientShader.h"
28 #include "include/effects/SkHighContrastFilter.h"
29 #include "include/effects/SkImageFilters.h"
30 #include "include/effects/SkShaderMaskFilter.h"
31 #include "include/gpu/GrDirectContext.h"
32 #include "tools/Resources.h"
33 #include "tools/ToolUtils.h"
34 
35 #include <utility>
36 
37 /**
38  *  Test drawing a primitive w/ an imagefilter (in this case, just matrix w/ identity) to see
39  *  that we apply the xfermode *after* the image has been created and filtered, and not during
40  *  the creation step (i.e. before it is filtered).
41  *
42  *  see https://bug.skia.org/3741
43  */
do_draw(SkCanvas * canvas,SkBlendMode mode,sk_sp<SkImageFilter> imf)44 static void do_draw(SkCanvas* canvas, SkBlendMode mode, sk_sp<SkImageFilter> imf) {
45         SkAutoCanvasRestore acr(canvas, true);
46         canvas->clipRect(SkRect::MakeWH(220, 220));
47 
48         // want to force a layer, so modes like DstIn can combine meaningfully, but the final
49         // image can still be shown against our default (opaque) background. non-opaque GMs
50         // are a lot more trouble to compare/triage.
51         canvas->saveLayer(nullptr, nullptr);
52         canvas->drawColor(SK_ColorGREEN);
53 
54         SkPaint paint;
55         paint.setAntiAlias(true);
56 
57         SkRect r0 = SkRect::MakeXYWH(10, 60, 200, 100);
58         SkRect r1 = SkRect::MakeXYWH(60, 10, 100, 200);
59 
60         paint.setColor(SK_ColorRED);
61         canvas->drawOval(r0, paint);
62 
63         paint.setColor(0x660000FF);
64         paint.setImageFilter(std::move(imf));
65         paint.setBlendMode(mode);
66         canvas->drawOval(r1, paint);
67 }
68 
69 DEF_SIMPLE_GM(imagefilters_xfermodes, canvas, 480, 480) {
70         canvas->translate(10, 10);
71 
72         // just need an imagefilter to trigger the code-path (which creates a tmp layer)
73         sk_sp<SkImageFilter> imf(SkImageFilters::MatrixTransform(SkMatrix::I(),
74                                                                  kNone_SkFilterQuality,
75                                                                  nullptr));
76 
77         const SkBlendMode modes[] = {
78             SkBlendMode::kSrcATop, SkBlendMode::kDstIn
79         };
80 
81         for (size_t i = 0; i < SK_ARRAY_COUNT(modes); ++i) {
82             canvas->save();
83             do_draw(canvas, modes[i], nullptr);
84             canvas->translate(240, 0);
85             do_draw(canvas, modes[i], imf);
86             canvas->restore();
87 
88             canvas->translate(0, 240);
89         }
90 }
91 
make_image(SkCanvas * canvas)92 static sk_sp<SkImage> make_image(SkCanvas* canvas) {
93     const SkImageInfo info = SkImageInfo::MakeS32(100, 100, kPremul_SkAlphaType);
94     auto              surface(ToolUtils::makeSurface(canvas, info));
95     surface->getCanvas()->drawRect(SkRect::MakeXYWH(25, 25, 50, 50), SkPaint());
96     return surface->makeImageSnapshot();
97 }
98 
99 // Compare blurs when we're tightly clipped (fast) and not as tightly (slower)
100 //
101 // Expect the two to draw the same (modulo the extra border of pixels when the clip is larger)
102 //
103 DEF_SIMPLE_GM(fast_slow_blurimagefilter, canvas, 620, 260) {
104     sk_sp<SkImage> image(make_image(canvas));
105     const SkRect r = SkRect::MakeIWH(image->width(), image->height());
106 
107     canvas->translate(10, 10);
108     for (SkScalar sigma = 8; sigma <= 128; sigma *= 2) {
109         SkPaint paint;
110         paint.setImageFilter(SkImageFilters::Blur(sigma, sigma, nullptr));
111 
112         canvas->save();
113         // we outset the clip by 1, to fall out of the fast-case in drawImage
114         // i.e. the clip is larger than the image
115         for (SkScalar outset = 0; outset <= 1; ++outset) {
116             canvas->save();
117             canvas->clipRect(r.makeOutset(outset, outset));
118             canvas->drawImage(image, 0, 0, &paint);
119             canvas->restore();
120             canvas->translate(0, r.height() + 20);
121         }
122         canvas->restore();
123         canvas->translate(r.width() + 20, 0);
124     }
125 }
126 
127 ///////////////////////////////////////////////////////////////////////////////////////////////////
128 
draw_set(SkCanvas * canvas,sk_sp<SkImageFilter> filters[],int count)129 static void draw_set(SkCanvas* canvas, sk_sp<SkImageFilter> filters[], int count) {
130     const SkRect r = SkRect::MakeXYWH(30, 30, 200, 200);
131     const SkScalar offset = 250;
132     SkScalar dx = 0, dy = 0;
133 
134     for (int i = 0; i < count; ++i) {
135         canvas->save();
136         SkRRect rr = SkRRect::MakeRectXY(r.makeOffset(dx, dy), 20, 20);
137         canvas->clipRRect(rr, true);
138         canvas->saveLayer(SkCanvas::SaveLayerRec(&rr.getBounds(), nullptr, filters[i].get(), 0));
139         canvas->drawColor(0x40FFFFFF);
140         canvas->restore();
141         canvas->restore();
142 
143         if (0 == dx) {
144             dx = offset;
145         } else {
146             dx = 0;
147             dy = offset;
148         }
149     }
150 }
151 
152 class SaveLayerWithBackdropGM : public skiagm::GM {
153 protected:
runAsBench() const154     bool runAsBench() const override { return true; }
onShortName()155     SkString onShortName() override { return SkString("savelayer_with_backdrop"); }
onISize()156     SkISize onISize() override { return SkISize::Make(830, 550); }
157 
onDraw(SkCanvas * canvas)158     void onDraw(SkCanvas* canvas) override {
159         SkColorMatrix cm;
160         cm.setSaturation(10);
161         sk_sp<SkColorFilter> cf(SkColorFilters::Matrix(cm));
162         const SkScalar kernel[] = { 4, 0, 4, 0, -15, 0, 4, 0, 4 };
163         sk_sp<SkImageFilter> filters[] = {
164             SkImageFilters::Blur(10, 10, nullptr),
165             SkImageFilters::Dilate(8, 8, nullptr),
166             SkImageFilters::MatrixConvolution({ 3, 3 }, kernel, 1, 0, { 0, 0 },
167                                               SkTileMode::kDecal, true, nullptr),
168             SkImageFilters::ColorFilter(std::move(cf), nullptr),
169         };
170 
171         const struct {
172             SkScalar    fSx, fSy, fTx, fTy;
173         } xforms[] = {
174             { 1, 1, 0, 0 },
175             { 0.5f, 0.5f, 530, 0 },
176             { 0.25f, 0.25f, 530, 275 },
177             { 0.125f, 0.125f, 530, 420 },
178         };
179 
180         SkPaint paint;
181         paint.setFilterQuality(kMedium_SkFilterQuality);
182         sk_sp<SkImage> image(GetResourceAsImage("images/mandrill_512.png"));
183 
184         canvas->translate(20, 20);
185         for (const auto& xform : xforms) {
186             canvas->save();
187             canvas->translate(xform.fTx, xform.fTy);
188             canvas->scale(xform.fSx, xform.fSy);
189             canvas->drawImage(image, 0, 0, &paint);
190             draw_set(canvas, filters, SK_ARRAY_COUNT(filters));
191             canvas->restore();
192         }
193     }
194 };
195 
196 DEF_GM(return new SaveLayerWithBackdropGM();)
197 
198 ///////////////////////////////////////////////////////////////////////////////////////////////////
199 
200 // Test that color filters and mask filters are applied before the image filter, even if it would
201 // normally be a sprite draw that could avoid an auto-saveLayer.
202 DEF_SIMPLE_GM(imagefilters_effect_order, canvas, 512, 512) {
203     sk_sp<SkImage> image(GetResourceAsImage("images/mandrill_256.png"));
204     auto direct = GrAsDirectContext(canvas->recordingContext());
205     if (direct) {
206         if (sk_sp<SkImage> gpuImage = image->makeTextureImage(direct)) {
207             image = std::move(gpuImage);
208         }
209     }
210 
211     SkISize kernelSize = SkISize::Make(3, 3);
212     SkIPoint kernelOffset = SkIPoint::Make(1, 1);
213     // A Laplacian edge detector, ie https://en.wikipedia.org/wiki/Kernel_(image_processing)
214     SkScalar kernel[9] = {-1.f, -1.f, -1.f,
215                           -1.f,  8.f, -1.f,
216                           -1.f, -1.f, -1.f};
217     auto edgeDetector = SkImageFilters::MatrixConvolution(
218             kernelSize, kernel, 1.f, 0.f, kernelOffset, SkTileMode::kClamp, false, nullptr);
219     // This uses the high contrast filter because it resembles a pre-processing step you may perform
220     // prior to edge detection. The specifics of the high contrast algorithm don't matter for the GM
221     auto edgeAmplify = SkHighContrastFilter::Make(
222             {false, SkHighContrastConfig::InvertStyle::kNoInvert, 0.5f});
223 
224     SkPaint testCFPaint;
225     testCFPaint.setColorFilter(edgeAmplify);
226     testCFPaint.setImageFilter(edgeDetector);
227 
228     // The expected result is color filter then image filter, so represent this explicitly in the
229     // image filter graph.
230     SkPaint expectedCFPaint;
231     expectedCFPaint.setImageFilter(SkImageFilters::Compose(edgeDetector,
232             SkImageFilters::ColorFilter(edgeAmplify, nullptr)));
233 
234     // Draw the image twice (expected on the left, test on the right that should match)
235     SkRect crop = SkRect::Make(image->bounds());
236     canvas->save();
237     canvas->clipRect(crop);
238     canvas->drawImage(image, 0, 0, &expectedCFPaint); // Filter applied by draw's SkPaint
239     canvas->restore();
240 
241     canvas->save();
242     canvas->translate(image->width(), 0);
243     canvas->clipRect(crop);
244     canvas->drawImage(image, 0, 0, &testCFPaint);
245     canvas->restore();
246 
247     // Now test mask filters. These should be run before the image filter, and thus have the same
248     // effect as multiplying by an alpha mask.
249 
250     // This mask filter pokes a hole in the center of the image
251     static constexpr SkColor kAlphas[] = { SK_ColorBLACK, SK_ColorTRANSPARENT };
252     static constexpr SkScalar kPos[] = { 0.4f, 0.9f };
253     sk_sp<SkShader> alphaMaskShader = SkGradientShader::MakeRadial(
254             {128.f, 128.f}, 128.f, kAlphas, kPos, 2, SkTileMode::kClamp);
255     sk_sp<SkMaskFilter> maskFilter = SkShaderMaskFilter::Make(alphaMaskShader);
256 
257     // If edge detector sees the mask filter, it'll have alpha and then blend with the original
258     // image; otherwise the mask filter will apply late (incorrectly) and none of the original
259     // image will be visible.
260     sk_sp<SkImageFilter> edgeBlend = SkImageFilters::Blend(SkBlendMode::kSrcOver,
261             SkImageFilters::Image(image), edgeDetector);
262 
263     SkPaint testMaskPaint;
264     testMaskPaint.setMaskFilter(maskFilter);
265     testMaskPaint.setImageFilter(edgeBlend);
266 
267     SkPaint expectedMaskPaint;
268     expectedMaskPaint.setImageFilter(SkImageFilters::Compose(edgeBlend,
269             SkImageFilters::Blend(SkBlendMode::kSrcIn,
270                                   SkImageFilters::Shader(alphaMaskShader))));
271 
272     canvas->save();
273     canvas->translate(0, image->height());
274     canvas->clipRect(crop);
275     canvas->drawImage(image, 0, 0, &expectedMaskPaint);
276     canvas->restore();
277 
278     canvas->save();
279     canvas->translate(image->width(), image->height());
280     canvas->clipRect(crop);
281     canvas->drawImage(image, 0, 0, &testMaskPaint);
282     canvas->restore();
283 }
284