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/SkBlendMode.h"
10 #include "include/core/SkCanvas.h"
11 #include "include/core/SkColor.h"
12 #include "include/core/SkColorFilter.h"
13 #include "include/core/SkFont.h"
14 #include "include/core/SkFontTypes.h"
15 #include "include/core/SkPaint.h"
16 #include "include/core/SkPoint.h"
17 #include "include/core/SkRect.h"
18 #include "include/core/SkRefCnt.h"
19 #include "include/core/SkScalar.h"
20 #include "include/core/SkShader.h"
21 #include "include/core/SkSize.h"
22 #include "include/core/SkString.h"
23 #include "include/core/SkTileMode.h"
24 #include "include/core/SkTypeface.h"
25 #include "include/core/SkTypes.h"
26 #include "include/effects/SkGradientShader.h"
27 #include "include/effects/SkLumaColorFilter.h"
28 #include "tools/ToolUtils.h"
29
30 #include <string.h>
31
32 static SkScalar kSize = 80;
33 static SkScalar kInset = 10;
34 static SkColor kColor1 = SkColorSetARGB(0xff, 0xff, 0xff, 0);
35 static SkColor kColor2 = SkColorSetARGB(0xff, 0x82, 0xff, 0);
36
draw_label(SkCanvas * canvas,const char * label,const SkPoint & offset)37 static void draw_label(SkCanvas* canvas, const char* label,
38 const SkPoint& offset) {
39 SkFont font(ToolUtils::create_portable_typeface());
40 font.setEdging(SkFont::Edging::kAlias);
41
42 size_t len = strlen(label);
43
44 SkScalar width = font.measureText(label, len, SkTextEncoding::kUTF8);
45 canvas->drawSimpleText(label, len, SkTextEncoding::kUTF8, offset.x() - width / 2, offset.y(),
46 font, SkPaint());
47 }
48
draw_scene(SkCanvas * canvas,const sk_sp<SkColorFilter> & filter,SkBlendMode mode,const sk_sp<SkShader> & s1,const sk_sp<SkShader> & s2)49 static void draw_scene(SkCanvas* canvas, const sk_sp<SkColorFilter>& filter, SkBlendMode mode,
50 const sk_sp<SkShader>& s1, const sk_sp<SkShader>& s2) {
51 SkPaint paint;
52 paint.setAntiAlias(true);
53 SkRect r, c, bounds = SkRect::MakeWH(kSize, kSize);
54
55 c = bounds;
56 c.fRight = bounds.centerX();
57 paint.setARGB(0x20, 0, 0, 0xff);
58 canvas->drawRect(bounds, paint);
59
60 canvas->saveLayer(&bounds, nullptr);
61
62 r = bounds;
63 r.inset(kInset, 0);
64 paint.setShader(s1);
65 paint.setColor(s1 ? SK_ColorBLACK : SkColorSetA(kColor1, 0x80));
66 canvas->drawOval(r, paint);
67 if (!s1) {
68 canvas->save();
69 canvas->clipRect(c);
70 paint.setColor(kColor1);
71 canvas->drawOval(r, paint);
72 canvas->restore();
73 }
74
75 SkPaint xferPaint;
76 xferPaint.setBlendMode(mode);
77 canvas->saveLayer(&bounds, &xferPaint);
78
79 r = bounds;
80 r.inset(0, kInset);
81 paint.setShader(s2);
82 paint.setColor(s2 ? SK_ColorBLACK : SkColorSetA(kColor2, 0x80));
83 paint.setColorFilter(filter);
84 canvas->drawOval(r, paint);
85 if (!s2) {
86 canvas->save();
87 canvas->clipRect(c);
88 paint.setColor(kColor2);
89 canvas->drawOval(r, paint);
90 canvas->restore();
91 }
92
93 canvas->restore();
94 canvas->restore();
95 }
96
97 class LumaFilterGM : public skiagm::GM {
98 protected:
onOnceBeforeDraw()99 void onOnceBeforeDraw() override {
100 SkColor g1Colors[] = { kColor1, SkColorSetA(kColor1, 0x20) };
101 SkColor g2Colors[] = { kColor2, SkColorSetA(kColor2, 0x20) };
102 SkPoint g1Points[] = { { 0, 0 }, { 0, 100 } };
103 SkPoint g2Points[] = { { 0, 0 }, { kSize, 0 } };
104 SkScalar pos[] = { 0.2f, 1.0f };
105
106 fFilter = SkLumaColorFilter::Make();
107 fGr1 = SkGradientShader::MakeLinear(g1Points, g1Colors, pos, SK_ARRAY_COUNT(g1Colors),
108 SkTileMode::kClamp);
109 fGr2 = SkGradientShader::MakeLinear(g2Points, g2Colors, pos, SK_ARRAY_COUNT(g2Colors),
110 SkTileMode::kClamp);
111 }
112
onShortName()113 SkString onShortName() override {
114 return SkString("lumafilter");
115 }
116
onISize()117 SkISize onISize() override {
118 return SkISize::Make(600, 420);
119 }
120
onDraw(SkCanvas * canvas)121 void onDraw(SkCanvas* canvas) override {
122 SkBlendMode modes[] = {
123 SkBlendMode::kSrcOver,
124 SkBlendMode::kDstOver,
125 SkBlendMode::kSrcATop,
126 SkBlendMode::kDstATop,
127 SkBlendMode::kSrcIn,
128 SkBlendMode::kDstIn,
129 };
130 struct {
131 const sk_sp<SkShader>& fShader1;
132 const sk_sp<SkShader>& fShader2;
133 } shaders[] = {
134 { nullptr, nullptr },
135 { nullptr, fGr2 },
136 { fGr1, nullptr },
137 { fGr1, fGr2 },
138 };
139
140 SkScalar gridStep = kSize + 2 * kInset;
141 for (size_t i = 0; i < SK_ARRAY_COUNT(modes); ++i) {
142 draw_label(canvas, SkBlendMode_Name(modes[i]),
143 SkPoint::Make(gridStep * (0.5f + i), 20));
144 }
145
146 for (size_t i = 0; i < SK_ARRAY_COUNT(shaders); ++i) {
147 canvas->save();
148 canvas->translate(kInset, gridStep * i + 30);
149 for (size_t m = 0; m < SK_ARRAY_COUNT(modes); ++m) {
150 draw_scene(canvas, fFilter, modes[m], shaders[i].fShader1,
151 shaders[i].fShader2);
152 canvas->translate(gridStep, 0);
153 }
154 canvas->restore();
155 }
156 }
157
158 private:
159 sk_sp<SkColorFilter> fFilter;
160 sk_sp<SkShader> fGr1, fGr2;
161
162 using INHERITED = skiagm::GM;
163 };
164
165 //////////////////////////////////////////////////////////////////////////////
166
167 DEF_GM(return new LumaFilterGM;)
168