1 /*
2  * Copyright 2013 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/gm.h"
9 #include "include/core/SkCanvas.h"
10 #include "include/core/SkColor.h"
11 #include "include/core/SkPaint.h"
12 #include "include/core/SkPoint.h"
13 #include "include/core/SkRect.h"
14 #include "include/core/SkRefCnt.h"
15 #include "include/core/SkShader.h"
16 #include "include/core/SkSize.h"
17 #include "include/core/SkString.h"
18 #include "include/core/SkTileMode.h"
19 #include "include/core/SkTypes.h"
20 #include "include/effects/SkGradientShader.h"
21 
22 typedef sk_sp<SkShader> (*MakeShaderProc)(const SkColor[], int count, const SkSize&);
23 
shader_linear(const SkColor colors[],int count,const SkSize & size)24 static sk_sp<SkShader> shader_linear(const SkColor colors[], int count, const SkSize& size) {
25     SkPoint pts[] = { { 0, 0 }, { size.width(), size.height() } };
26     return SkGradientShader::MakeLinear(pts, colors, nullptr, count, SkTileMode::kClamp);
27 }
28 
shader_radial(const SkColor colors[],int count,const SkSize & size)29 static sk_sp<SkShader> shader_radial(const SkColor colors[], int count, const SkSize& size) {
30     SkPoint center = { size.width()/2, size.height()/2 };
31     return SkGradientShader::MakeRadial(center, size.width()/2, colors, nullptr, count,
32                                         SkTileMode::kClamp);
33 }
34 
shader_conical(const SkColor colors[],int count,const SkSize & size)35 static sk_sp<SkShader> shader_conical(const SkColor colors[], int count, const SkSize& size) {
36     SkPoint center = { size.width()/2, size.height()/2 };
37     return SkGradientShader::MakeTwoPointConical(center, size.width()/64, center, size.width()/2,
38                                                 colors, nullptr, count, SkTileMode::kClamp);
39 }
40 
shader_sweep(const SkColor colors[],int count,const SkSize & size)41 static sk_sp<SkShader> shader_sweep(const SkColor colors[], int count, const SkSize& size) {
42     return SkGradientShader::MakeSweep(size.width()/2, size.height()/2, colors, nullptr, count);
43 }
44 
45 class ShallowGradientGM : public skiagm::GM {
46 public:
ShallowGradientGM(MakeShaderProc proc,const char name[],bool dither)47     ShallowGradientGM(MakeShaderProc proc, const char name[], bool dither)
48         : fProc(proc), fName(name), fDither(dither) {}
49 
50 private:
51     MakeShaderProc fProc;
52     const char* fName;
53     bool fDither;
54 
onShortName()55     SkString onShortName() override {
56         return SkStringPrintf("shallow_gradient_%s%s", fName, fDither ? "" : "_nodither");
57     }
58 
onISize()59     SkISize onISize() override { return {800, 800}; }
60 
onDraw(SkCanvas * canvas)61     void onDraw(SkCanvas* canvas) override {
62         const SkColor colors[] = { 0xFF555555, 0xFF444444 };
63         const int colorCount = SK_ARRAY_COUNT(colors);
64 
65         SkRect r = { 0, 0, this->width(), this->height() };
66         SkSize size = SkSize::Make(r.width(), r.height());
67 
68         SkPaint paint;
69         paint.setShader(fProc(colors, colorCount, size));
70         paint.setDither(fDither);
71         canvas->drawRect(r, paint);
72     }
73 };
74 
75 ///////////////////////////////////////////////////////////////////////////////
76 
77 #define M(PROC, DITHER) DEF_GM( return new ShallowGradientGM(shader_ ## PROC, #PROC, DITHER); )
78 M(linear,  true)
79 M(radial,  true)
80 M(conical, true)
81 M(sweep,   true)
82 
83 M(linear,  false)
84 M(radial,  false)
85 M(conical, false)
86 M(sweep,   false)
87 #undef M
88