aosp12/external/skia/docs/examples/UnpremulGPU.cpp

36 lines
1.3 KiB
C++

// Copyright 2020 Google LLC.
// Use of this source code is governed by a BSD-style license that can be found in the LICENSE file.
#include "tools/fiddle/examples.h"
REG_FIDDLE(UnpremulGPU, 256, 256, false, 6) {
void draw(SkCanvas* canvas) {
canvas->clear(0xffa020a0);
SkImageInfo premulInfo = SkImageInfo::MakeS32(10, 10, kPremul_SkAlphaType);
SkBitmap premulBitmap;
premulBitmap.allocPixels(premulInfo);
for (int y = 0; y < 10; y++) {
for (int x = 0; x < 10; x++) {
*(premulBitmap.getAddr32(x, y)) = 0x80808080;
}
}
sk_sp<SkImage> premulImage = premulBitmap.asImage();
SkImageInfo unpremulInfo = premulInfo.makeAlphaType(kUnpremul_SkAlphaType);
SkBitmap unpremulBitmap;
unpremulBitmap.allocPixels(unpremulInfo);
for (int y = 0; y < 10; y++) {
for (int x = 0; x < 10; x++) {
*(unpremulBitmap.getAddr32(x, y)) = 0x80FFFFFF;
}
}
sk_sp<SkImage> unpremulImage = unpremulBitmap.asImage();
SkPaint paint;
const SkTileMode tile = SkTileMode::kRepeat;
paint.setShader(premulImage->makeShader(tile, tile, SkSamplingOptions()));
canvas->drawCircle(10.0f, 10.0f, 10.0f, paint);
paint.setShader(unpremulImage->makeShader(tile, tile, SkSamplingOptions()));
canvas->drawCircle(10.0f, 35.0f, 10.0f, paint);
}
} // END FIDDLE