1/*
2 * Copyright 2017 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 "include/core/SkCanvas.h"
9#include "include/core/SkColorFilter.h"
10#include "include/core/SkImage.h"
11#include "include/core/SkPath.h"
12#include "include/core/SkRegion.h"
13#include "include/core/SkShader.h"
14#include "include/effects/SkGradientShader.h"
15#include "samplecode/Sample.h"
16#include "src/core/SkUtils.h"
17#include "tools/Resources.h"
18
19const float gMat[] = {
20    .3f, .6f, .1f, 0, 0,
21    .3f, .6f, .1f, 0, 0,
22    .3f, .6f, .1f, 0, 0,
23      0,   0,   0, 1, 0,
24};
25
26class MixerView : public Sample {
27    sk_sp<SkImage>          fImg;
28    sk_sp<SkColorFilter>    fCF0;
29    sk_sp<SkColorFilter>    fCF1;
30
31    float fWeight = 0;
32    float fDW = 0.02f;
33
34public:
35    MixerView() {}
36
37protected:
38    SkString name() override { return SkString("Mixer"); }
39
40    void dodraw(SkCanvas* canvas, sk_sp<SkColorFilter> cf0, sk_sp<SkColorFilter> cf1, float gap) {
41        SkPaint paint;
42        paint.setColorFilter(cf0);
43        canvas->drawImage(fImg, 0, 0, SkSamplingOptions(), &paint);
44
45        paint.setColorFilter(SkColorFilters::Lerp(fWeight, cf0, cf1));
46        canvas->drawImage(fImg, fImg->width() + gap * fWeight, 0,
47                          SkSamplingOptions(), &paint);
48
49        paint.setColorFilter(cf1);
50        canvas->drawImage(fImg, 2*fImg->width() + gap, 0, SkSamplingOptions(), &paint);
51    }
52
53    void onDrawContent(SkCanvas* canvas) override {
54        if (!fImg) {
55            fImg = GetResourceAsImage("images/mandrill_256.png");
56            fCF0 = SkColorFilters::Matrix(gMat);
57            fCF1 = SkColorFilters::Blend(0xFF44CC88, SkBlendMode::kScreen);
58        }
59
60        float gap = fImg->width() * 3;
61
62        canvas->translate(10, 10);
63        dodraw(canvas, nullptr, fCF1, gap);
64        canvas->translate(0, fImg->height() + 10);
65        dodraw(canvas, fCF0, nullptr, gap);
66        canvas->translate(0, fImg->height() + 10);
67        dodraw(canvas, fCF0, fCF1, gap);
68
69        fWeight += fDW;
70        if (fWeight > 1 || fWeight < 0) {
71            fDW = -fDW;
72        }
73    }
74
75    Click* onFindClickHandler(SkScalar x, SkScalar y, skui::ModifierKey) override {
76        return fRect.contains(SkScalarRoundToInt(x),
77                              SkScalarRoundToInt(y)) ? new Click() : nullptr;
78    }
79
80    bool onClick(Click* click) override {
81        fRect.offset(click->fCurr.fX - click->fPrev.fX,
82                     click->fCurr.fY - click->fPrev.fY);
83        return true;
84    }
85
86private:
87    SkIRect fRect;
88
89    using INHERITED = Sample;
90};
91DEF_SAMPLE( return new MixerView; )
92