1// Copyright 2019 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"
4// HASH=0424f67ebc2858e8fd04ae3367b115ff
5REG_FIDDLE(Alpha_Constants_b, 256, 128, false, 1) {
6void draw(SkCanvas* canvas) {
7    std::vector<int32_t> srcPixels;
8    srcPixels.resize(source.height() * source.rowBytes());
9    SkPixmap pixmap(SkImageInfo::MakeN32Premul(source.width(), source.height()),
10                    &srcPixels.front(), source.rowBytes());
11    source.readPixels(pixmap, 0, 0);
12    for (int y = 0; y < source.height(); ++y) {
13        for (int x = 0; x < source.width(); ++x) {
14            SkPMColor pixel = srcPixels[y * source.width() + x];
15            const SkColor color = SkUnPreMultiply::PMColorToColor(pixel);
16            if (SkColorGetA(color) == SK_AlphaOPAQUE) {
17                srcPixels[y * source.width() + x] = SK_ColorGREEN;
18            }
19        }
20    }
21    canvas->drawImage(SkImage::MakeRasterCopy(pixmap), 0, 0);
22}
23}  // END FIDDLE
24