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 "SkColorMatrixFilter.h"
11#include "SkGradientShader.h"
12#include "SkImage.h"
13
14#define WIDTH 500
15#define HEIGHT 500
16
17static void set_color_matrix(SkPaint* paint, const SkColorMatrix& matrix) {
18    paint->setColorFilter(SkColorFilter::MakeMatrixFilterRowMajor255(matrix.fMat));
19}
20
21static void set_array(SkPaint* paint, const SkScalar array[]) {
22    paint->setColorFilter(SkColorFilter::MakeMatrixFilterRowMajor255(array));
23}
24
25class ColorMatrixGM : public skiagm::GM {
26public:
27    ColorMatrixGM() {
28        this->setBGColor(sk_tool_utils::color_to_565(0xFF808080));
29    }
30
31protected:
32    SkString onShortName() override {
33        return SkString("colormatrix");
34    }
35
36    SkISize onISize() override {
37        return SkISize::Make(WIDTH, HEIGHT);
38    }
39
40    void onOnceBeforeDraw() override {
41        fSolidImg = CreateSolidBitmap(64, 64);
42        fTransparentImg = CreateTransparentBitmap(64, 64);
43    }
44
45    static sk_sp<SkImage> CreateSolidBitmap(int width, int height) {
46        SkBitmap bm;
47        bm.allocN32Pixels(width, height);
48        SkCanvas canvas(bm);
49        canvas.clear(0x0);
50        for (int y = 0; y < height; ++y) {
51            for (int x = 0; x < width; ++x) {
52                SkPaint paint;
53                paint.setColor(SkColorSetARGB(255, x * 255 / width, y * 255 / height, 0));
54                canvas.drawRect(SkRect::MakeXYWH(SkIntToScalar(x),
55                    SkIntToScalar(y), SK_Scalar1, SK_Scalar1), paint);
56            }
57        }
58        return SkImage::MakeFromBitmap(bm);
59    }
60
61    // creates a bitmap with shades of transparent gray.
62    static sk_sp<SkImage> CreateTransparentBitmap(int width, int height) {
63        SkBitmap bm;
64        bm.allocN32Pixels(width, height);
65        SkCanvas canvas(bm);
66        canvas.clear(0x0);
67
68        SkPoint pts[] = {{0, 0}, {SkIntToScalar(width), SkIntToScalar(height)}};
69        SkColor colors[] = {0x00000000, 0xFFFFFFFF};
70        SkPaint paint;
71        paint.setShader(SkGradientShader::MakeLinear(pts, colors, nullptr, 2,
72                                                     SkShader::kClamp_TileMode));
73        canvas.drawRect(SkRect::MakeWH(SkIntToScalar(width), SkIntToScalar(height)), paint);
74        return SkImage::MakeFromBitmap(bm);
75    }
76
77    void onDraw(SkCanvas* canvas) override {
78        SkPaint paint;
79        SkColorMatrix matrix;
80
81        paint.setBlendMode(SkBlendMode::kSrc);
82        const SkImage* bmps[] = { fSolidImg.get(), fTransparentImg.get() };
83
84        for (size_t i = 0; i < SK_ARRAY_COUNT(bmps); ++i) {
85            matrix.setIdentity();
86            set_color_matrix(&paint, matrix);
87            canvas->drawImage(bmps[i], 0, 0, &paint);
88
89            matrix.setRotate(SkColorMatrix::kR_Axis, 90);
90            set_color_matrix(&paint, matrix);
91            canvas->drawImage(bmps[i], 80, 0, &paint);
92
93            matrix.setRotate(SkColorMatrix::kG_Axis, 90);
94            set_color_matrix(&paint, matrix);
95            canvas->drawImage(bmps[i], 160, 0, &paint);
96
97            matrix.setRotate(SkColorMatrix::kB_Axis, 90);
98            set_color_matrix(&paint, matrix);
99            canvas->drawImage(bmps[i], 240, 0, &paint);
100            ///////////////////////////////////////////////
101            matrix.setSaturation(0.0f);
102            set_color_matrix(&paint, matrix);
103            canvas->drawImage(bmps[i], 0, 80, &paint);
104
105            matrix.setSaturation(0.5f);
106            set_color_matrix(&paint, matrix);
107            canvas->drawImage(bmps[i], 80, 80, &paint);
108
109            matrix.setSaturation(1.0f);
110            set_color_matrix(&paint, matrix);
111            canvas->drawImage(bmps[i], 160, 80, &paint);
112
113            matrix.setSaturation(2.0f);
114            set_color_matrix(&paint, matrix);
115            canvas->drawImage(bmps[i], 240, 80, &paint);
116            ///////////////////////////////////////////////
117            matrix.setRGB2YUV();
118            set_color_matrix(&paint, matrix);
119            canvas->drawImage(bmps[i], 0, 160, &paint);
120
121            matrix.setYUV2RGB();
122            set_color_matrix(&paint, matrix);
123            canvas->drawImage(bmps[i], 80, 160, &paint);
124
125            SkScalar s1 = SK_Scalar1;
126            SkScalar s255 = SkIntToScalar(255);
127            // Move red into alpha, set color to white
128            SkScalar data[20] = {
129                0,  0, 0, 0, s255,
130                0,  0, 0, 0, s255,
131                0,  0, 0, 0, s255,
132                s1, 0, 0, 0, 0,
133            };
134
135            set_array(&paint, data);
136            canvas->drawImage(bmps[i], 160, 160, &paint);
137            ///////////////////////////////////////////////
138            canvas->translate(0, 240);
139        }
140    }
141
142private:
143    sk_sp<SkImage>   fSolidImg;
144    sk_sp<SkImage>   fTransparentImg;
145
146    typedef skiagm::GM INHERITED;
147};
148DEF_GM( return new ColorMatrixGM; )
149