xref: /third_party/skia/docs/examples/blur4444.cpp (revision cb93a386)
1// Copyright 2020 Google LLC.
2// Use of this source code is governed by a BSD-style license that can be found in the LICENSE file.
3#include "tools/fiddle/examples.h"
4REG_FIDDLE(blur4444, 650, 480, false, 0) {
5void draw(SkCanvas* canvas) {
6    bool forceRaster = false;
7    bool dither = false;
8    bool postDither = false;
9
10    canvas->clear(SK_ColorTRANSPARENT);
11    SkPaint grayPaint;
12    grayPaint.setColor(SK_ColorGRAY);
13    SkPaint ltGrayPaint;
14    ltGrayPaint.setColor(SK_ColorLTGRAY);
15    canvas->drawRect({350, 0, 400, 480}, ltGrayPaint);
16    canvas->drawRect({400, 0, 500, 480}, grayPaint);
17    canvas->drawRect({500, 0, 640, 480}, SkPaint());
18    canvas->drawRect({0, 200, 320, 215}, ltGrayPaint);
19    canvas->drawRect({0, 215, 320, 230}, grayPaint);
20    canvas->drawRect({0, 230, 320, 250}, SkPaint());
21
22    sk_sp<SkSurface> surf;
23    auto ii = SkImageInfo::Make(650, 480, kARGB_4444_SkColorType, kPremul_SkAlphaType);
24    if (canvas->recordingContext() && !forceRaster) {
25        surf = SkSurface::MakeRenderTarget(canvas->recordingContext(), SkBudgeted::kNo, ii);
26    } else {
27        surf = SkSurface::MakeRaster(ii);
28    }
29    if (!surf) {
30        return;
31    }
32
33    auto c = surf->getCanvas();
34    c->clear(SK_ColorTRANSPARENT);
35
36    SkPaint blrPaint;
37    blrPaint.setAntiAlias(true);
38    blrPaint.setMaskFilter(SkMaskFilter::MakeBlur(kNormal_SkBlurStyle, 12.047));
39    blrPaint.setBlendMode(SkBlendMode::kSrc);
40    blrPaint.setDither(dither);
41
42    blrPaint.setColor(SK_ColorWHITE);
43    c->drawRect(SkRect{0, 20, 640, 104}, blrPaint);
44
45    blrPaint.setColor(SkColorSetARGB(255, 247, 247, 247));
46    c->drawRect(SkRect{0, 0, 640, 84}.makeOffset(0, 300), blrPaint);
47
48    static constexpr SkColor colors[]{SkColorSetARGB(255, 247, 247, 247), 0};
49    static constexpr SkPoint pts[]{{0.5, 0}, {256.5, 0}};
50    auto grd = SkGradientShader::MakeLinear(pts, colors, nullptr, 2, SkTileMode::kClamp);
51    SkPaint grdPaint;
52    grdPaint.setShader(grd);
53    grdPaint.setDither(dither);
54
55    c->drawRect(SkRect{0, 0, 640, 100}.makeOffset(0, 150), grdPaint);
56
57    SkPaint postPaint;
58    postPaint.setDither(postDither);
59    surf->draw(canvas, 0, 0, SkSamplingOptions(), &postPaint);
60}
61}  // END FIDDLE
62