1 /*
2  * Copyright 2016 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/SkCanvas.h"
10 #include "include/core/SkColor.h"
11 #include "include/core/SkImageInfo.h"
12 #include "include/core/SkMatrix.h"
13 #include "include/core/SkPaint.h"
14 #include "include/core/SkPoint.h"
15 #include "include/core/SkRRect.h"
16 #include "include/core/SkRect.h"
17 #include "include/core/SkScalar.h"
18 #include "include/core/SkSize.h"
19 #include "include/core/SkString.h"
20 #include "include/core/SkTypes.h"
21 #include "include/private/SkTArray.h"
22 #include "include/utils/SkRandom.h"
23 
24 namespace skiagm {
25 
26 /*
27  * This is the base class for two GMs that cover various corner cases with primitive Skia shapes
28  * (zero radius, near-zero radius, inner shape overlap, etc.) It uses an xfermode of darken to help
29  * double-blended and/or dropped pixels stand out.
30  */
31 class ShapesGM : public GM {
32 protected:
ShapesGM(const char * name,bool antialias)33     ShapesGM(const char* name, bool antialias) : fName(name), fAntialias(antialias) {
34         if (!antialias) {
35             fName.append("_bw");
36         }
37     }
38 
onShortName()39     SkString onShortName() final { return fName; }
onISize()40     SkISize onISize() override { return SkISize::Make(500, 500); }
41 
onOnceBeforeDraw()42     void onOnceBeforeDraw() override {
43         fShapes.push_back().setOval(SkRect::MakeXYWH(-5, 25, 200, 100));
44         fRotations.push_back(21);
45 
46         fShapes.push_back().setRect(SkRect::MakeXYWH(95, 75, 125, 100));
47         fRotations.push_back(94);
48 
49         fShapes.push_back().setRectXY(SkRect::MakeXYWH(0, 75, 150, 100), 1e-5f, 1e-5f);
50         fRotations.push_back(132);
51 
52         fShapes.push_back().setRectXY(SkRect::MakeXYWH(15, -20, 100, 100), 20, 15);
53         fRotations.push_back(282);
54 
55         fSimpleShapeCount = fShapes.count();
56 
57         fShapes.push_back().setNinePatch(SkRect::MakeXYWH(140, -50, 90, 110), 10, 5, 25, 35);
58         fRotations.push_back(0);
59 
60         fShapes.push_back().setNinePatch(SkRect::MakeXYWH(160, -60, 60, 90), 10, 60, 50, 30);
61         fRotations.push_back(-35);
62 
63         fShapes.push_back().setNinePatch(SkRect::MakeXYWH(220, -120, 60, 90), 1, 89, 59, 1);
64         fRotations.push_back(65);
65 
66         SkVector radii[4] = {{4, 6}, {12, 8}, {24, 16}, {32, 48}};
67         fShapes.push_back().setRectRadii(SkRect::MakeXYWH(150, -129, 80, 160), radii);
68         fRotations.push_back(265);
69 
70         SkVector radii2[4] = {{0, 0}, {80, 60}, {0, 0}, {80, 60}};
71         fShapes.push_back().setRectRadii(SkRect::MakeXYWH(180, -30, 80, 60), radii2);
72         fRotations.push_back(295);
73 
74         fPaint.setAntiAlias(fAntialias);
75     }
76 
onDraw(SkCanvas * canvas)77     void onDraw(SkCanvas* canvas) override {
78         canvas->clear(SK_ColorWHITE);
79 
80         canvas->save();
81         canvas->translate(canvas->imageInfo().width() / 2.f, canvas->imageInfo().height() / 2.f);
82         this->drawShapes(canvas);
83         canvas->restore();
84     }
85 
86     virtual void drawShapes(SkCanvas* canvas) const = 0;
87 
88 protected:
89     SkString             fName;
90     bool                 fAntialias;
91     SkPaint              fPaint;
92     SkTArray<SkRRect>    fShapes;
93     SkTArray<SkScalar>   fRotations;
94     int                  fSimpleShapeCount;
95 
96 private:
97     using INHERITED = GM;
98 };
99 
100 class SimpleShapesGM : public ShapesGM {
101 public:
SimpleShapesGM(bool antialias)102     SimpleShapesGM(bool antialias) : INHERITED("simpleshapes", antialias) {}
103 
104 private:
drawShapes(SkCanvas * canvas) const105     void drawShapes(SkCanvas* canvas) const override {
106         SkRandom rand(2);
107         for (int i = 0; i < fShapes.count(); i++) {
108             SkPaint paint(fPaint);
109             paint.setColor(rand.nextU() & ~0x808080);
110             paint.setAlphaf(0.5f);  // Use alpha to detect double blends.
111             const SkRRect& shape = fShapes[i];
112             canvas->save();
113             canvas->rotate(fRotations[i]);
114             switch (shape.getType()) {
115                 case SkRRect::kRect_Type:
116                     canvas->drawRect(shape.rect(), paint);
117                     break;
118                 case SkRRect::kOval_Type:
119                     canvas->drawOval(shape.rect(), paint);
120                     break;
121                 default:
122                     canvas->drawRRect(shape, paint);
123                     break;
124             }
125             canvas->restore();
126         }
127     }
128 
129     using INHERITED = ShapesGM;
130 };
131 
132 class InnerShapesGM : public ShapesGM {
133 public:
InnerShapesGM(bool antialias)134     InnerShapesGM(bool antialias) : INHERITED("innershapes", antialias) {}
135 
136 private:
drawShapes(SkCanvas * canvas) const137     void drawShapes(SkCanvas* canvas) const override {
138         SkRandom rand;
139         for (int i = 0; i < fShapes.count(); i++) {
140             const SkRRect& outer = fShapes[i];
141             const SkRRect& inner = fShapes[(i * 7 + 11) % fSimpleShapeCount];
142             float s = 0.95f * std::min(outer.rect().width() / inner.rect().width(),
143                                      outer.rect().height() / inner.rect().height());
144             SkMatrix innerXform;
145             float dx = (rand.nextF() - 0.5f) * (outer.rect().width() - s * inner.rect().width());
146             float dy = (rand.nextF() - 0.5f) * (outer.rect().height() - s * inner.rect().height());
147             innerXform.setTranslate(outer.rect().centerX() + dx, outer.rect().centerY() + dy);
148             if (s < 1) {
149                 innerXform.preScale(s, s);
150             }
151             innerXform.preTranslate(-inner.rect().centerX(), -inner.rect().centerY());
152             SkRRect xformedInner;
153             inner.transform(innerXform, &xformedInner);
154             SkPaint paint(fPaint);
155             paint.setColor(rand.nextU() & ~0x808080);
156             paint.setAlphaf(0.5f);  // Use alpha to detect double blends.
157             canvas->save();
158             canvas->rotate(fRotations[i]);
159             canvas->drawDRRect(outer, xformedInner, paint);
160             canvas->restore();
161         }
162     }
163 
164     using INHERITED = ShapesGM;
165 };
166 
167 //////////////////////////////////////////////////////////////////////////////
168 
169 DEF_GM( return new SimpleShapesGM(true); )
170 DEF_GM( return new SimpleShapesGM(false); )
171 DEF_GM( return new InnerShapesGM(true); )
172 DEF_GM( return new InnerShapesGM(false); )
173 
174 }  // namespace skiagm
175