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 "sk_tool_utils.h"
10 #include "SkCanvas.h"
11 #include "SkGradientShader.h"
12 
13 namespace skiagm {
14 
makebm(SkBitmap * bm,int w,int h)15 static void makebm(SkBitmap* bm, int w, int h) {
16     bm->allocN32Pixels(w, h);
17     bm->eraseColor(SK_ColorTRANSPARENT);
18 
19     SkCanvas    canvas(*bm);
20     SkScalar    s = SkIntToScalar(SkMin32(w, h));
21     const SkPoint     kPts0[] = { { 0, 0 }, { s, s } };
22     const SkPoint     kPts1[] = { { s/2, 0 }, { s/2, s } };
23     const SkScalar    kPos[] = { 0, SK_Scalar1/2, SK_Scalar1 };
24     const SkColor kColors0[] = {0x80F00080, 0xF0F08000, 0x800080F0 };
25     const SkColor kColors1[] = {0xF08000F0, 0x8080F000, 0xF000F080 };
26 
27 
28     SkPaint     paint;
29 
30     paint.setShader(SkGradientShader::MakeLinear(kPts0, kColors0, kPos,
31                     SK_ARRAY_COUNT(kColors0), SkShader::kClamp_TileMode));
32     canvas.drawPaint(paint);
33     paint.setShader(SkGradientShader::MakeLinear(kPts1, kColors1, kPos,
34                     SK_ARRAY_COUNT(kColors1), SkShader::kClamp_TileMode));
35     canvas.drawPaint(paint);
36 }
37 
38 ///////////////////////////////////////////////////////////////////////////////
39 
40 struct LabeledMatrix {
41     SkMatrix    fMatrix;
42     const char* fLabel;
43 };
44 
45 constexpr int kPointSize = 300;
46 
47 class ShaderText3GM : public GM {
48 public:
ShaderText3GM()49     ShaderText3GM() {
50         this->setBGColor(0xFFDDDDDD);
51     }
52 
53 protected:
54 
onShortName()55     SkString onShortName() override {
56         return SkString("shadertext3");
57     }
58 
onISize()59     SkISize onISize() override{ return SkISize::Make(820, 930); }
60 
onOnceBeforeDraw()61     void onOnceBeforeDraw() override {
62         makebm(&fBmp, kPointSize / 4, kPointSize / 4);
63     }
64 
onDraw(SkCanvas * canvas)65     void onDraw(SkCanvas* canvas) override {
66 
67         SkPaint bmpPaint;
68         bmpPaint.setAntiAlias(true);
69         bmpPaint.setFilterQuality(kLow_SkFilterQuality);
70         bmpPaint.setAlphaf(0.5f);
71         canvas->drawBitmap(fBmp, 5.f, 5.f, &bmpPaint);
72 
73         SkFont font(sk_tool_utils::create_portable_typeface(), SkIntToScalar(kPointSize));
74         SkPaint outlinePaint;
75         outlinePaint.setStyle(SkPaint::kStroke_Style);
76         outlinePaint.setStrokeWidth(0.f);
77 
78         canvas->translate(15.f, 15.f);
79 
80         // draw glyphs scaled up
81         canvas->scale(2.f, 2.f);
82 
83         constexpr SkShader::TileMode kTileModes[] = {
84             SkShader::kRepeat_TileMode,
85             SkShader::kMirror_TileMode,
86         };
87 
88         // position the baseline of the first run
89         canvas->translate(0.f, 0.75f * kPointSize);
90 
91         canvas->save();
92         int i = 0;
93         for (size_t tm0 = 0; tm0 < SK_ARRAY_COUNT(kTileModes); ++tm0) {
94             for (size_t tm1 = 0; tm1 < SK_ARRAY_COUNT(kTileModes); ++tm1) {
95                 SkMatrix localM;
96                 localM.setTranslate(5.f, 5.f);
97                 localM.postRotate(20);
98                 localM.postScale(1.15f, .85f);
99 
100                 SkPaint fillPaint;
101                 fillPaint.setAntiAlias(true);
102                 fillPaint.setFilterQuality(kLow_SkFilterQuality);
103                 fillPaint.setShader(SkShader::MakeBitmapShader(fBmp, kTileModes[tm0],
104                                                                kTileModes[tm1], &localM));
105 
106                 constexpr char kText[] = "B";
107                 canvas->drawString(kText, 0, 0, font, fillPaint);
108                 canvas->drawString(kText, 0, 0, font, outlinePaint);
109                 SkScalar w = font.measureText(kText, strlen(kText), kUTF8_SkTextEncoding);
110                 canvas->translate(w + 10.f, 0.f);
111                 ++i;
112                 if (!(i % 2)) {
113                     canvas->restore();
114                     canvas->translate(0, 0.75f * kPointSize);
115                     canvas->save();
116                 }
117             }
118         }
119         canvas->restore();
120     }
121 
122 private:
123     SkBitmap fBmp;
124     typedef GM INHERITED;
125 };
126 
127 ///////////////////////////////////////////////////////////////////////////////
128 
129 DEF_GM( return new ShaderText3GM; )
130 }
131