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 "gm.h"
9 #include "SkCanvas.h"
10 #include "SkColorPriv.h"
11 #include "SkShader.h"
12
13 #include "SkArithmeticMode.h"
14 #include "SkGradientShader.h"
15 #define WW 100
16 #define HH 32
17
make_bm()18 static SkBitmap make_bm() {
19 SkBitmap bm;
20 bm.setConfig(SkBitmap::kARGB_8888_Config, WW, HH);
21 bm.allocPixels();
22 bm.eraseColor(0);
23 return bm;
24 }
25
make_src()26 static SkBitmap make_src() {
27 SkBitmap bm = make_bm();
28 SkCanvas canvas(bm);
29 SkPaint paint;
30 SkPoint pts[] = { {0, 0}, {SkIntToScalar(WW), SkIntToScalar(HH)} };
31 SkColor colors[] = {
32 SK_ColorBLACK, SK_ColorGREEN, SK_ColorCYAN,
33 SK_ColorRED, SK_ColorMAGENTA, SK_ColorWHITE
34 };
35 SkShader* s = SkGradientShader::CreateLinear(pts, colors, NULL, SK_ARRAY_COUNT(colors),
36 SkShader::kClamp_TileMode);
37 paint.setShader(s)->unref();
38 canvas.drawPaint(paint);
39 return bm;
40 }
41
make_dst()42 static SkBitmap make_dst() {
43 SkBitmap bm = make_bm();
44 SkCanvas canvas(bm);
45 SkPaint paint;
46 SkPoint pts[] = { {0, SkIntToScalar(HH)}, {SkIntToScalar(WW), 0} };
47 SkColor colors[] = {
48 SK_ColorBLUE, SK_ColorYELLOW, SK_ColorBLACK, SK_ColorGREEN, SK_ColorGRAY
49 };
50 SkShader* s = SkGradientShader::CreateLinear(pts, colors, NULL, SK_ARRAY_COUNT(colors),
51 SkShader::kClamp_TileMode);
52 paint.setShader(s)->unref();
53 canvas.drawPaint(paint);
54 return bm;
55 }
56
make_arith(const SkBitmap & src,const SkBitmap & dst,const SkScalar k[])57 static SkBitmap make_arith(const SkBitmap& src, const SkBitmap& dst,
58 const SkScalar k[]) {
59 SkBitmap bm = make_bm();
60 SkCanvas canvas(bm);
61 SkPaint paint;
62 canvas.drawBitmap(dst, 0, 0, NULL);
63 SkXfermode* xfer = SkArithmeticMode::Create(k[0], k[1], k[2], k[3]);
64 paint.setXfermode(xfer)->unref();
65 canvas.drawBitmap(src, 0, 0, &paint);
66 return bm;
67 }
68
show_k_text(SkCanvas * canvas,SkScalar x,SkScalar y,const SkScalar k[])69 static void show_k_text(SkCanvas* canvas, SkScalar x, SkScalar y, const SkScalar k[]) {
70 SkPaint paint;
71 paint.setTextSize(SkIntToScalar(24));
72 paint.setAntiAlias(true);
73 for (int i = 0; i < 4; ++i) {
74 SkString str;
75 str.appendScalar(k[i]);
76 SkScalar width = paint.measureText(str.c_str(), str.size());
77 canvas->drawText(str.c_str(), str.size(), x, y + paint.getTextSize(), paint);
78 x += width + SkIntToScalar(10);
79 }
80 }
81
82 class ArithmodeGM : public skiagm::GM {
83 public:
ArithmodeGM()84 ArithmodeGM () {}
85
86 protected:
87
onShortName()88 virtual SkString onShortName() {
89 return SkString("arithmode");
90 }
91
onISize()92 virtual SkISize onISize() { return SkISize::Make(640, 480); }
93
onDraw(SkCanvas * canvas)94 virtual void onDraw(SkCanvas* canvas) {
95 SkBitmap src = make_src();
96 SkBitmap dst = make_dst();
97
98 const SkScalar one = SK_Scalar1;
99 static const SkScalar K[] = {
100 0, 0, 0, 0,
101 0, 0, 0, one,
102 0, one, 0, 0,
103 0, 0, one, 0,
104 0, one, one, 0,
105 0, one, -one, 0,
106 0, one/2, one/2, 0,
107 0, one/2, one/2, one/4,
108 0, one/2, one/2, -one/4,
109 one/4, one/2, one/2, 0,
110 -one/4, one/2, one/2, 0,
111 };
112
113 const SkScalar* k = K;
114 const SkScalar* stop = k + SK_ARRAY_COUNT(K);
115 SkScalar y = 0;
116 SkScalar x = 0;
117 SkScalar gap = SkIntToScalar(src.width() + 20);
118 while (k < stop) {
119 SkScalar x = 0;
120 SkBitmap res = make_arith(src, dst, k);
121 canvas->drawBitmap(src, x, y, NULL);
122 x += gap;
123 canvas->drawBitmap(dst, x, y, NULL);
124 x += gap;
125 canvas->drawBitmap(res, x, y, NULL);
126 x += gap;
127 show_k_text(canvas, x, y, k);
128 k += 4;
129 y += SkIntToScalar(src.height() + 12);
130 }
131 }
132
133 private:
134 typedef GM INHERITED;
135 };
136
137 ///////////////////////////////////////////////////////////////////////////////
138
MyFactory(void *)139 static skiagm::GM* MyFactory(void*) { return new ArithmodeGM; }
140 static skiagm::GMRegistry reg(MyFactory);
141