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
5 REG_FIDDLE(Alpha_Constants_b, 256, 128, false, 1) {
draw(SkCanvas * canvas)6 void 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