skia2/docs/examples/Pixmap_readPixels.cpp
Herb Derby 5623d9e36f Replace SK_ARRAY_COUNT with std::size() for skia/docs
Change-Id: I9569ba4760546be6302c24658e64cb58c7db86e5
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/550697
Reviewed-by: John Stiles <johnstiles@google.com>
Commit-Queue: Herb Derby <herb@google.com>
2022-06-16 20:09:58 +00:00

32 lines
1.4 KiB
C++

// Copyright 2019 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"
// HASH=df4e355c4845350daede833b4fd21ec1
REG_FIDDLE(Pixmap_readPixels, 256, 128, false, 0) {
void draw(SkCanvas* canvas) {
std::vector<int32_t> pixels;
const int width = 256;
const int height = 64;
pixels.resize(height * width * 4);
SkImageInfo srcInfo = SkImageInfo::MakeN32Premul(width, height);
SkPixmap srcPixmap(srcInfo, (const void*) &pixels.front(), width * 4);
SkColor gradColors[] = { 0xFFAA3300, 0x7F881122 };
SkPoint gradPoints[] = { { 0, 0 }, { 256, 0 } };
SkPaint paint;
paint.setShader(SkGradientShader::MakeLinear(gradPoints, gradColors, nullptr,
std::size(gradColors), SkTileMode::kClamp));
SkBitmap bitmap;
bitmap.installPixels(srcPixmap);
SkCanvas srcCanvas(bitmap);
srcCanvas.drawRect(SkRect::MakeWH(width, height), paint);
canvas->drawImage(bitmap.asImage(), 0, 0);
std::vector<int32_t> dstPixels;
dstPixels.resize(height * width * 2);
SkImageInfo dstInfo = srcInfo.makeColorType(kARGB_4444_SkColorType);
srcPixmap.readPixels(dstInfo, &dstPixels.front(), width * 2);
SkPixmap dstPixmap(dstInfo, &dstPixels.front(), width * 2);
bitmap.installPixels(dstPixmap);
canvas->drawImage(bitmap.asImage(), 0, 128);
}
} // END FIDDLE