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 #include "SampleCode.h"
8 #include "SkView.h"
9 #include "SkCanvas.h"
10 #include "SkGraphics.h"
11 #include "SkPath.h"
12 #include "SkRandom.h"
13 #include "SkString.h"
14 #include "SkTime.h"
15 
16 class PolyToPolyView : public SampleView {
17 public:
18     PolyToPolyView() {
19         // tests
20         {
21             SkPoint src[] = { { 0, 0 },
22                               { SK_Scalar1, 0 },
23                               { 0, SK_Scalar1 } };
24             SkPoint dst[] = { { 0, 0 },
25                               { 2*SK_Scalar1, 0 },
26                               { 0, 2*SK_Scalar1 } };
27             SkMatrix m1, m2;
28 
29             (void) m1.setPolyToPoly(src, dst, 3);
30 
31             m2.reset();
32             m2.set(SkMatrix::kMScaleX, dst[1].fX - dst[0].fX);
33             m2.set(SkMatrix::kMSkewX,  dst[2].fX - dst[0].fX);
34             m2.set(SkMatrix::kMTransX, dst[0].fX);
35             m2.set(SkMatrix::kMSkewY,  dst[1].fY - dst[0].fY);
36             m2.set(SkMatrix::kMScaleY, dst[2].fY - dst[0].fY);
37             m2.set(SkMatrix::kMTransY, dst[0].fY);
38 
39             m1.reset();
40 
41             const SkScalar src1[] = {
42                 0, 0, 0, 427, 316, 427, 316, 0
43             };
44             const SkScalar dst1[] = {
45                 158, 177.5f, 158, 249.5f,
46                 158, 604.5f, 158, -177.5f
47             };
48 
49             (void) m2.setPolyToPoly((const SkPoint*)src1, (SkPoint*)dst1, 4);
50 
51             {
52                 const SkPoint src[] = {
53                     { SkIntToScalar(1), SkIntToScalar(0) },
54                     { SkIntToScalar(4), SkIntToScalar(7) },
55                     { SkIntToScalar(10), SkIntToScalar(2) }
56                 };
57                 const SkPoint dst[] = {
58                     { SkIntToScalar(4), SkIntToScalar(2) },
59                     { SkIntToScalar(45), SkIntToScalar(26) },
60                     { SkIntToScalar(32), SkIntToScalar(17) }
61                 };
62 
63                 SkMatrix m0;
64                 m0.setPolyToPoly(src, dst, 3);
65             }
66         }
67     }
68 
69 protected:
70     // overrides from SkEventSink
71     virtual bool onQuery(SkEvent* evt)  {
72         if (SampleCode::TitleQ(*evt)) {
73             SampleCode::TitleR(evt, "PolyToPolyView");
74             return true;
75         }
76         return this->INHERITED::onQuery(evt);
77     }
78 
79     static void doDraw(SkCanvas* canvas, SkPaint* paint, const int isrc[],
80                        const int idst[], int count) {
81         SkMatrix matrix;
82         SkPoint src[4], dst[4];
83 
84         for (int i = 0; i < count; i++) {
85             src[i].set(SkIntToScalar(isrc[2*i+0]), SkIntToScalar(isrc[2*i+1]));
86             dst[i].set(SkIntToScalar(idst[2*i+0]), SkIntToScalar(idst[2*i+1]));
87         }
88 
89         canvas->save();
90         matrix.setPolyToPoly(src, dst, count);
91         canvas->concat(matrix);
92 
93         paint->setColor(SK_ColorGRAY);
94         paint->setStyle(SkPaint::kStroke_Style);
95         const SkScalar D = SkIntToScalar(64);
96         canvas->drawRect(SkRect::MakeWH(D, D), *paint);
97         canvas->drawLine(0, 0, D, D, *paint);
98         canvas->drawLine(0, D, D, 0, *paint);
99 
100         SkPaint::FontMetrics fm;
101         paint->getFontMetrics(&fm);
102         paint->setColor(SK_ColorRED);
103         paint->setStyle(SkPaint::kFill_Style);
104         SkScalar x = D/2;
105         float y = D/2 - (fm.fAscent + fm.fDescent)/2;
106         SkString str;
107         str.appendS32(count);
108         canvas->drawString(str,
109                          x, y,
110                          *paint);
111 
112         canvas->restore();
113     }
114 
115     virtual void onDrawContent(SkCanvas* canvas) {
116         SkPaint paint;
117         paint.setAntiAlias(true);
118         paint.setStrokeWidth(SkIntToScalar(4));
119         paint.setTextSize(SkIntToScalar(40));
120         paint.setTextAlign(SkPaint::kCenter_Align);
121 
122         canvas->save();
123         canvas->translate(SkIntToScalar(10), SkIntToScalar(10));
124         // translate (1 point)
125         const int src1[] = { 0, 0 };
126         const int dst1[] = { 5, 5 };
127         doDraw(canvas, &paint, src1, dst1, 1);
128         canvas->restore();
129 
130         canvas->save();
131         canvas->translate(SkIntToScalar(160), SkIntToScalar(10));
132         // rotate/uniform-scale (2 points)
133         const int src2[] = { 32, 32, 64, 32 };
134         const int dst2[] = { 32, 32, 64, 48 };
135         doDraw(canvas, &paint, src2, dst2, 2);
136         canvas->restore();
137 
138         canvas->save();
139         canvas->translate(SkIntToScalar(10), SkIntToScalar(110));
140         // rotate/skew (3 points)
141         const int src3[] = { 0, 0, 64, 0, 0, 64 };
142         const int dst3[] = { 0, 0, 96, 0, 24, 64 };
143         doDraw(canvas, &paint, src3, dst3, 3);
144         canvas->restore();
145 
146         canvas->save();
147         canvas->translate(SkIntToScalar(160), SkIntToScalar(110));
148         // perspective (4 points)
149         const int src4[] = { 0, 0, 64, 0, 64, 64, 0, 64 };
150         const int dst4[] = { 0, 0, 96, 0, 64, 96, 0, 64 };
151         doDraw(canvas, &paint, src4, dst4, 4);
152         canvas->restore();
153     }
154 
155 private:
156     typedef SampleView INHERITED;
157 };
158 
159 //////////////////////////////////////////////////////////////////////////////
160 
161 static SkView* MyFactory() { return new PolyToPolyView; }
162 static SkViewRegister reg(MyFactory);
163