xref: /aosp_15_r20/external/skia/tools/viewer/LayersSlide.cpp (revision c8dee2aa9b3f27cf6c858bd81872bdeb2c07ed17)
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 "include/core/SkCanvas.h"
9 #include "include/core/SkColorFilter.h"
10 #include "include/core/SkColorPriv.h"
11 #include "include/core/SkImage.h"
12 #include "include/core/SkMaskFilter.h"
13 #include "include/core/SkPath.h"
14 #include "include/core/SkRegion.h"
15 #include "include/core/SkShader.h"
16 #include "include/core/SkTypeface.h"
17 #include "include/effects/SkGradientShader.h"
18 #include "include/utils/SkCamera.h"
19 #include "src/base/SkTime.h"
20 #include "src/base/SkUTF.h"
21 #include "tools/DecodeUtils.h"
22 #include "tools/viewer/ClickHandlerSlide.h"
23 #include "tools/viewer/Slide.h"
24 
make_paint(SkPaint * paint,const SkMatrix & localMatrix)25 static void make_paint(SkPaint* paint, const SkMatrix& localMatrix) {
26     SkColor colors[] = { 0, SK_ColorWHITE };
27     SkPoint pts[] = { { 0, 0 }, { 0, SK_Scalar1*20 } };
28     paint->setShader(SkGradientShader::MakeLinear(pts, colors, nullptr, 2,
29                                                   SkTileMode::kClamp, 0, &localMatrix));
30     paint->setBlendMode(SkBlendMode::kDstIn);
31 }
32 
33 // test drawing with strips of fading gradient above and below
test_fade(SkCanvas * canvas)34 static void test_fade(SkCanvas* canvas) {
35     SkAutoCanvasRestore ar(canvas, true);
36 
37     SkRect r;
38 
39     SkAutoCanvasRestore ar2(canvas, false);
40 
41     // create the layers
42 
43     r.setWH(100, 100);
44     canvas->clipRect(r);
45 
46     r.fBottom = SkIntToScalar(20);
47     canvas->saveLayer(&r, nullptr);
48 
49     r.fTop = SkIntToScalar(80);
50     r.fBottom = SkIntToScalar(100);
51     canvas->saveLayer(&r, nullptr);
52 
53     // now draw the "content"
54 
55     if ((true)) {
56         r.setWH(100, 100);
57 
58         canvas->saveLayerAlpha(&r, 0x80);
59 
60         SkPaint p;
61         p.setColor(SK_ColorRED);
62         p.setAntiAlias(true);
63         canvas->drawOval(r, p);
64 
65         canvas->restore();
66     } else {
67         r.setWH(100, 100);
68 
69         SkPaint p;
70         p.setColor(SK_ColorRED);
71         p.setAntiAlias(true);
72         canvas->drawOval(r, p);
73     }
74 
75 //    return;
76 
77     // now apply an effect
78     SkMatrix m;
79     m.setScale(SK_Scalar1, -SK_Scalar1);
80     m.postTranslate(0, SkIntToScalar(100));
81 
82     SkPaint paint;
83     make_paint(&paint, m);
84     r.setWH(100, 20);
85 //    SkDebugf("--------- draw top grad\n");
86     canvas->drawRect(r, paint);
87 
88     r.fTop = SkIntToScalar(80);
89     r.fBottom = SkIntToScalar(100);
90 //    SkDebugf("--------- draw bot grad\n");
91     canvas->drawRect(r, paint);
92 }
93 
94 class LayersSlide : public Slide {
95 public:
LayersSlide()96     LayersSlide() { fName = "Layers"; }
97 
draw(SkCanvas * canvas)98     void draw(SkCanvas* canvas) override {
99         canvas->drawColor(SK_ColorGRAY);
100 
101         if ((true)) {
102             SkRect r;
103             r.setWH(220, 120);
104             SkPaint p;
105             canvas->saveLayer(&r, &p);
106             canvas->drawColor(0xFFFF0000);
107             p.setAlpha(0);  // or 0
108             p.setBlendMode(SkBlendMode::kSrc);
109             canvas->drawOval(r, p);
110             canvas->restore();
111             return;
112         }
113 
114         if ((false)) {
115             SkRect r;
116             r.setWH(220, 120);
117             SkPaint p;
118             p.setAlpha(0x88);
119             p.setAntiAlias(true);
120 
121             if (true) {
122                 canvas->saveLayer(&r, &p);
123                 p.setColor(0xFFFF0000);
124                 canvas->drawOval(r, p);
125                 canvas->restore();
126             }
127 
128             p.setColor(0xFF0000FF);
129             r.offset(SkIntToScalar(20), SkIntToScalar(50));
130             canvas->drawOval(r, p);
131         }
132 
133         if ((false)) {
134             SkPaint p;
135             p.setAlpha(0x88);
136             p.setAntiAlias(true);
137 
138             canvas->translate(SkIntToScalar(300), 0);
139 
140             SkRect r;
141             r.setWH(220, 60);
142 
143             canvas->saveLayer(&r, &p);
144 
145             r.setWH(220, 120);
146             p.setColor(SK_ColorBLUE);
147             canvas->drawOval(r, p);
148             canvas->restore();
149             return;
150         }
151 
152         test_fade(canvas);
153     }
154 };
155 DEF_SLIDE( return new LayersSlide; )
156 
157 //////////////////////////////////////////////////////////////////////////////
158 
159 #include "include/effects/SkImageFilters.h"
160 
161 #include "tools/Resources.h"
162 
163 class BackdropSlide : public ClickHandlerSlide {
164     SkPoint fCenter;
165     SkScalar fAngle;
166     sk_sp<SkImage> fImage;
167     sk_sp<SkImageFilter> fFilter;
168 
169 public:
BackdropSlide()170     BackdropSlide() {
171         fName = "Backdrop";
172     }
173 
174 protected:
load(SkScalar,SkScalar)175     void load(SkScalar, SkScalar) override {
176         fCenter.set(200, 150);
177         fAngle = 0;
178         fImage = ToolUtils::GetResourceAsImage("images/mandrill_512.png");
179         fFilter = SkImageFilters::Dilate(8, 8, nullptr);
180     }
181 
draw(SkCanvas * canvas)182     void draw(SkCanvas* canvas) override {
183         canvas->drawImage(fImage.get(), 0, 0);
184 
185         const SkScalar w = 250;
186         const SkScalar h = 150;
187         SkPath path;
188         path.addOval(SkRect::MakeXYWH(-w/2, -h/2, w, h));
189         SkMatrix m;
190         m.setRotate(fAngle);
191         m.postTranslate(fCenter.x(), fCenter.y());
192         path.transform(m);
193 
194         canvas->clipPath(path, SkClipOp::kIntersect, true);
195         const SkRect bounds = path.getBounds();
196 
197         SkPaint paint;
198         paint.setAlpha(0xCC);
199         canvas->saveLayer(SkCanvas::SaveLayerRec(&bounds, &paint, fFilter.get(), 0));
200 
201         canvas->restore();
202     }
203 
animate(double nanos)204     bool animate(double nanos) override {
205         fAngle = SkDoubleToScalar(fmod(1e-9 * nanos * 360 / 5, 360));
206         return true;
207     }
208 
209 protected:
onFindClickHandler(SkScalar x,SkScalar y,skui::ModifierKey modi)210     Click* onFindClickHandler(SkScalar x, SkScalar y, skui::ModifierKey modi) override {
211         return new Click();
212     }
213 
onClick(Click * click)214     bool onClick(Click* click) override {
215         fCenter = click->fCurr;
216         return true;
217     }
218 };
219 
220 DEF_SLIDE( return new BackdropSlide; )
221