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