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 "SkGradientShader.h"
11
12namespace skiagm {
13
14static void makebm(SkBitmap* bm, int w, int h) {
15    bm->allocN32Pixels(w, h);
16    bm->eraseColor(SK_ColorTRANSPARENT);
17
18    SkCanvas    canvas(*bm);
19    SkScalar    s = SkIntToScalar(SkMin32(w, h));
20    SkPoint     pts[] = { { 0, 0 }, { s, s } };
21    SkColor     colors[] = { SK_ColorRED, SK_ColorGREEN, SK_ColorBLUE };
22    SkScalar    pos[] = { 0, SK_Scalar1/2, SK_Scalar1 };
23    SkPaint     paint;
24
25    paint.setDither(true);
26    paint.setShader(SkGradientShader::CreateLinear(pts, colors, pos,
27                SK_ARRAY_COUNT(colors), SkShader::kClamp_TileMode))->unref();
28    canvas.drawPaint(paint);
29}
30
31///////////////////////////////////////////////////////////////////////////////
32
33struct GradData {
34    int             fCount;
35    const SkColor*  fColors;
36    const SkScalar* fPos;
37};
38
39static const SkColor gColors[] = {
40    SK_ColorRED, SK_ColorGREEN, SK_ColorBLUE, SK_ColorWHITE, SK_ColorBLACK
41};
42
43static const GradData gGradData[] = {
44    { 2, gColors, NULL },
45    { 5, gColors, NULL },
46};
47
48static SkShader* MakeLinear(const SkPoint pts[2], const GradData& data, SkShader::TileMode tm) {
49    return SkGradientShader::CreateLinear(pts, data.fColors, data.fPos, data.fCount, tm);
50}
51
52static SkShader* MakeRadial(const SkPoint pts[2], const GradData& data, SkShader::TileMode tm) {
53    SkPoint center;
54    center.set(SkScalarAve(pts[0].fX, pts[1].fX),
55               SkScalarAve(pts[0].fY, pts[1].fY));
56    return SkGradientShader::CreateRadial(center, center.fX, data.fColors,
57                                          data.fPos, data.fCount, tm);
58}
59
60static SkShader* MakeSweep(const SkPoint pts[2], const GradData& data, SkShader::TileMode) {
61    SkPoint center;
62    center.set(SkScalarAve(pts[0].fX, pts[1].fX),
63               SkScalarAve(pts[0].fY, pts[1].fY));
64    return SkGradientShader::CreateSweep(center.fX, center.fY, data.fColors, data.fPos, data.fCount);
65}
66
67static SkShader* Make2Conical(const SkPoint pts[2], const GradData& data, SkShader::TileMode tm) {
68    SkPoint center0, center1;
69    center0.set(SkScalarAve(pts[0].fX, pts[1].fX),
70                SkScalarAve(pts[0].fY, pts[1].fY));
71    center1.set(SkScalarInterp(pts[0].fX, pts[1].fX, SkIntToScalar(3)/5),
72                SkScalarInterp(pts[0].fY, pts[1].fY, SkIntToScalar(1)/4));
73    return SkGradientShader::CreateTwoPointConical(
74                            center1, (pts[1].fX - pts[0].fX) / 7,
75                            center0, (pts[1].fX - pts[0].fX) / 2,
76                            data.fColors, data.fPos, data.fCount, tm);
77}
78
79typedef SkShader* (*GradMaker)(const SkPoint pts[2], const GradData& data, SkShader::TileMode tm);
80
81static const GradMaker gGradMakers[] = {
82    MakeLinear, MakeRadial, MakeSweep, Make2Conical
83};
84
85///////////////////////////////////////////////////////////////////////////////
86
87class ShaderTextGM : public GM {
88public:
89    ShaderTextGM() {
90        this->setBGColor(0xFFDDDDDD);
91    }
92
93protected:
94
95    SkString onShortName() override {
96        return SkString("shadertext");
97    }
98
99    SkISize onISize() override { return SkISize::Make(1450, 500); }
100
101    void onDraw(SkCanvas* canvas) override {
102        const char text[] = "Shaded Text";
103        const int textLen = SK_ARRAY_COUNT(text) - 1;
104        const int pointSize = 36;
105
106        const int w = pointSize * textLen;
107        const int h = pointSize;
108
109        SkPoint pts[2] = {
110            { 0, 0 },
111            { SkIntToScalar(w), SkIntToScalar(h) }
112        };
113        SkScalar textBase = SkIntToScalar(h/2);
114
115        SkShader::TileMode tileModes[] = {
116            SkShader::kClamp_TileMode,
117            SkShader::kRepeat_TileMode,
118            SkShader::kMirror_TileMode
119        };
120
121        static const int gradCount = SK_ARRAY_COUNT(gGradData) *
122                                     SK_ARRAY_COUNT(gGradMakers);
123        static const int bmpCount = SK_ARRAY_COUNT(tileModes) *
124                                    SK_ARRAY_COUNT(tileModes);
125        SkShader* shaders[gradCount + bmpCount];
126
127        int shdIdx = 0;
128        for (size_t d = 0; d < SK_ARRAY_COUNT(gGradData); ++d) {
129            for (size_t m = 0; m < SK_ARRAY_COUNT(gGradMakers); ++m) {
130                shaders[shdIdx++] = gGradMakers[m](pts,
131                                                   gGradData[d],
132                                                   SkShader::kClamp_TileMode);
133            }
134        }
135
136        SkBitmap bm;
137        makebm(&bm, w/16, h/4);
138        for (size_t tx = 0; tx < SK_ARRAY_COUNT(tileModes); ++tx) {
139            for (size_t ty = 0; ty < SK_ARRAY_COUNT(tileModes); ++ty) {
140                shaders[shdIdx++] = SkShader::CreateBitmapShader(bm, tileModes[tx], tileModes[ty]);
141            }
142        }
143
144        SkPaint paint;
145        paint.setDither(true);
146        paint.setAntiAlias(true);
147        sk_tool_utils::set_portable_typeface(&paint);
148        paint.setTextSize(SkIntToScalar(pointSize));
149
150        canvas->save();
151        canvas->translate(SkIntToScalar(20), SkIntToScalar(10));
152
153        SkPath path;
154        path.arcTo(SkRect::MakeXYWH(SkIntToScalar(-40), SkIntToScalar(15),
155                                    SkIntToScalar(300), SkIntToScalar(90)),
156                                    SkIntToScalar(225), SkIntToScalar(90),
157                                    false);
158        path.close();
159
160        static const int testsPerCol = 8;
161        static const int rowHeight = 60;
162        static const int colWidth = 300;
163        canvas->save();
164        for (int s = 0; s < static_cast<int>(SK_ARRAY_COUNT(shaders)); s++) {
165            canvas->save();
166            int i = 2*s;
167            canvas->translate(SkIntToScalar((i / testsPerCol) * colWidth),
168                              SkIntToScalar((i % testsPerCol) * rowHeight));
169            paint.setShader(shaders[s])->unref();
170            canvas->drawText(text, textLen, 0, textBase, paint);
171            canvas->restore();
172            canvas->save();
173            ++i;
174            canvas->translate(SkIntToScalar((i / testsPerCol) * colWidth),
175                              SkIntToScalar((i % testsPerCol) * rowHeight));
176            canvas->drawTextOnPath(text, textLen, path, NULL, paint);
177            canvas->restore();
178        }
179        canvas->restore();
180
181    }
182
183private:
184    typedef GM INHERITED;
185};
186
187///////////////////////////////////////////////////////////////////////////////
188
189static GM* MyFactory(void*) { return new ShaderTextGM; }
190static GMRegistry reg(MyFactory);
191}
192