1
2 /*
3 * Copyright 2011 Google Inc.
4 *
5 * Use of this source code is governed by a BSD-style license that can be
6 * found in the LICENSE file.
7 */
8 #include "SampleCode.h"
9 #include "SkView.h"
10 #include "SkCanvas.h"
11 #include "SkGradientShader.h"
12 #include "SkUnitMappers.h"
13
makebm(SkBitmap * bm,SkBitmap::Config config,int w,int h)14 static void makebm(SkBitmap* bm, SkBitmap::Config config, int w, int h) {
15 bm->setConfig(config, w, h);
16 bm->allocPixels();
17 bm->eraseColor(0);
18
19 SkCanvas canvas(*bm);
20 SkScalar s = SkIntToScalar(w < h ? w : h);
21 SkPoint pts[] = { { 0, 0 }, { s, s } };
22 SkColor colors[] = { SK_ColorRED, SK_ColorGREEN, SK_ColorBLUE };
23 SkScalar pos[] = { 0, SK_Scalar1/2, SK_Scalar1 };
24 SkPaint paint;
25
26 SkUnitMapper* um = NULL;
27
28 um = new SkCosineMapper;
29
30 SkAutoUnref au(um);
31
32 paint.setDither(true);
33 paint.setShader(SkGradientShader::CreateLinear(pts, colors, pos,
34 SK_ARRAY_COUNT(colors), SkShader::kClamp_TileMode, um))->unref();
35 canvas.drawPaint(paint);
36 }
37
MakeBitmapShader(SkShader::TileMode tx,SkShader::TileMode ty,int w,int h)38 SkShader* MakeBitmapShader(SkShader::TileMode tx, SkShader::TileMode ty,
39 int w, int h) {
40 static SkBitmap bmp;
41 if (bmp.isNull()) {
42 makebm(&bmp, SkBitmap::kARGB_8888_Config, w/2, h/4);
43 }
44 return SkShader::CreateBitmapShader(bmp, tx, ty);
45 }
46
47 ///////////////////////////////////////////////////////////////////////////////
48
49 struct GradData {
50 int fCount;
51 const SkColor* fColors;
52 const SkScalar* fPos;
53 };
54
55 static const SkColor gColors[] = {
56 SK_ColorRED, SK_ColorGREEN, SK_ColorBLUE, SK_ColorWHITE, SK_ColorBLACK
57 };
58
59 static const GradData gGradData[] = {
60 { 2, gColors, NULL },
61 { 5, gColors, NULL },
62 };
63
MakeLinear(const SkPoint pts[2],const GradData & data,SkShader::TileMode tm,SkUnitMapper * mapper)64 static SkShader* MakeLinear(const SkPoint pts[2], const GradData& data,
65 SkShader::TileMode tm, SkUnitMapper* mapper) {
66 return SkGradientShader::CreateLinear(pts, data.fColors, data.fPos,
67 data.fCount, tm, mapper);
68 }
69
MakeRadial(const SkPoint pts[2],const GradData & data,SkShader::TileMode tm,SkUnitMapper * mapper)70 static SkShader* MakeRadial(const SkPoint pts[2], const GradData& data,
71 SkShader::TileMode tm, SkUnitMapper* mapper) {
72 SkPoint center;
73 center.set(SkScalarAve(pts[0].fX, pts[1].fX),
74 SkScalarAve(pts[0].fY, pts[1].fY));
75 return SkGradientShader::CreateRadial(center, center.fX, data.fColors,
76 data.fPos, data.fCount, tm, mapper);
77 }
78
MakeSweep(const SkPoint pts[2],const GradData & data,SkShader::TileMode tm,SkUnitMapper * mapper)79 static SkShader* MakeSweep(const SkPoint pts[2], const GradData& data,
80 SkShader::TileMode tm, SkUnitMapper* mapper) {
81 SkPoint center;
82 center.set(SkScalarAve(pts[0].fX, pts[1].fX),
83 SkScalarAve(pts[0].fY, pts[1].fY));
84 return SkGradientShader::CreateSweep(center.fX, center.fY, data.fColors,
85 data.fPos, data.fCount, mapper);
86 }
87
Make2Radial(const SkPoint pts[2],const GradData & data,SkShader::TileMode tm,SkUnitMapper * mapper)88 static SkShader* Make2Radial(const SkPoint pts[2], const GradData& data,
89 SkShader::TileMode tm, SkUnitMapper* mapper) {
90 SkPoint center0, center1;
91 center0.set(SkScalarAve(pts[0].fX, pts[1].fX),
92 SkScalarAve(pts[0].fY, pts[1].fY));
93 center1.set(SkScalarInterp(pts[0].fX, pts[1].fX, SkIntToScalar(3)/5),
94 SkScalarInterp(pts[0].fY, pts[1].fY, SkIntToScalar(1)/4));
95 return SkGradientShader::CreateTwoPointRadial(
96 center1, (pts[1].fX - pts[0].fX) / 7,
97 center0, (pts[1].fX - pts[0].fX) / 2,
98 data.fColors, data.fPos, data.fCount, tm, mapper);
99 }
100
101 typedef SkShader* (*GradMaker)(const SkPoint pts[2], const GradData& data,
102 SkShader::TileMode tm, SkUnitMapper* mapper);
103 static const GradMaker gGradMakers[] = {
104 MakeLinear, MakeRadial, MakeSweep, Make2Radial
105 };
106
107 ///////////////////////////////////////////////////////////////////////////////
108
109 class ShaderTextView : public SampleView {
110 public:
ShaderTextView()111 ShaderTextView() {
112 this->setBGColor(0xFFDDDDDD);
113 }
114
115 protected:
116 // overrides from SkEventSink
onQuery(SkEvent * evt)117 virtual bool onQuery(SkEvent* evt) {
118 if (SampleCode::TitleQ(*evt)) {
119 SampleCode::TitleR(evt, "Shader Text");
120 return true;
121 }
122 return this->INHERITED::onQuery(evt);
123 }
124
onDrawContent(SkCanvas * canvas)125 virtual void onDrawContent(SkCanvas* canvas) {
126 const char text[] = "Shaded Text";
127 const int textLen = SK_ARRAY_COUNT(text) - 1;
128 static int pointSize = 36;
129
130 int w = pointSize * textLen;
131 int h = pointSize;
132
133 SkPoint pts[2] = {
134 { 0, 0 },
135 { SkIntToScalar(w), SkIntToScalar(h) }
136 };
137 SkScalar textBase = SkIntToScalar(h/2);
138
139 SkShader::TileMode tileModes[] = {
140 SkShader::kClamp_TileMode,
141 SkShader::kRepeat_TileMode,
142 SkShader::kMirror_TileMode
143 };
144
145 static const int gradCount = SK_ARRAY_COUNT(gGradData) *
146 SK_ARRAY_COUNT(gGradMakers);
147 static const int bmpCount = SK_ARRAY_COUNT(tileModes) *
148 SK_ARRAY_COUNT(tileModes);
149 SkShader* shaders[gradCount + bmpCount];
150
151 int shdIdx = 0;
152 for (size_t d = 0; d < SK_ARRAY_COUNT(gGradData); ++d) {
153 for (size_t m = 0; m < SK_ARRAY_COUNT(gGradMakers); ++m) {
154 shaders[shdIdx++] = gGradMakers[m](pts,
155 gGradData[d],
156 SkShader::kClamp_TileMode,
157 NULL);
158 }
159 }
160 for (size_t tx = 0; tx < SK_ARRAY_COUNT(tileModes); ++tx) {
161 for (size_t ty = 0; ty < SK_ARRAY_COUNT(tileModes); ++ty) {
162 shaders[shdIdx++] = MakeBitmapShader(tileModes[tx],
163 tileModes[ty],
164 w/8, h);
165 }
166 }
167
168 SkPaint paint;
169 paint.setDither(true);
170 paint.setAntiAlias(true);
171 paint.setTextSize(SkIntToScalar(pointSize));
172
173 canvas->save();
174 canvas->translate(SkIntToScalar(20), SkIntToScalar(10));
175
176 SkPath path;
177 path.arcTo(SkRect::MakeXYWH(SkIntToScalar(-40), SkIntToScalar(15),
178 SkIntToScalar(300), SkIntToScalar(90)),
179 SkIntToScalar(225), SkIntToScalar(90),
180 false);
181 path.close();
182
183 static const int testsPerCol = 8;
184 static const int rowHeight = 60;
185 static const int colWidth = 300;
186 canvas->save();
187 for (size_t s = 0; s < SK_ARRAY_COUNT(shaders); s++) {
188 canvas->save();
189 int i = 2*s;
190 canvas->translate(SkIntToScalar((i / testsPerCol) * colWidth),
191 SkIntToScalar((i % testsPerCol) * rowHeight));
192 paint.setShader(shaders[s])->unref();
193 canvas->drawText(text, textLen, 0, textBase, paint);
194 canvas->restore();
195 canvas->save();
196 ++i;
197 canvas->translate(SkIntToScalar((i / testsPerCol) * colWidth),
198 SkIntToScalar((i % testsPerCol) * rowHeight));
199 canvas->drawTextOnPath(text, textLen, path, NULL, paint);
200 canvas->restore();
201 }
202 canvas->restore();
203
204 canvas->translate(0, SkIntToScalar(370));
205 this->inval(NULL);
206 }
207
208 private:
209 typedef SampleView INHERITED;
210 };
211
212 ///////////////////////////////////////////////////////////////////////////////
213
MyFactory()214 static SkView* MyFactory() { return new ShaderTextView; }
215 static SkViewRegister reg(MyFactory);
216
217