xref: /aosp_15_r20/external/skia/docs/examples/Pixmap_readPixels.cpp (revision c8dee2aa9b3f27cf6c858bd81872bdeb2c07ed17)
1*c8dee2aaSAndroid Build Coastguard Worker // Copyright 2019 Google LLC.
2*c8dee2aaSAndroid Build Coastguard Worker // Use of this source code is governed by a BSD-style license that can be found in the LICENSE file.
3*c8dee2aaSAndroid Build Coastguard Worker #include "tools/fiddle/examples.h"
4*c8dee2aaSAndroid Build Coastguard Worker REG_FIDDLE(Pixmap_readPixels, 256, 128, false, 0) {
draw(SkCanvas * canvas)5*c8dee2aaSAndroid Build Coastguard Worker void draw(SkCanvas* canvas) {
6*c8dee2aaSAndroid Build Coastguard Worker     std::vector<int32_t> pixels;
7*c8dee2aaSAndroid Build Coastguard Worker     const int width = 256;
8*c8dee2aaSAndroid Build Coastguard Worker     const int height = 64;
9*c8dee2aaSAndroid Build Coastguard Worker     pixels.resize(height * width * 4);
10*c8dee2aaSAndroid Build Coastguard Worker     SkImageInfo srcInfo = SkImageInfo::MakeN32Premul(width, height);
11*c8dee2aaSAndroid Build Coastguard Worker     SkPixmap srcPixmap(srcInfo, (const void*) &pixels.front(), width * 4);
12*c8dee2aaSAndroid Build Coastguard Worker     SkColor  gradColors[] = { 0xFFAA3300, 0x7F881122 };
13*c8dee2aaSAndroid Build Coastguard Worker     SkPoint  gradPoints[] = { { 0, 0 }, { 256, 0 } };
14*c8dee2aaSAndroid Build Coastguard Worker     SkPaint paint;
15*c8dee2aaSAndroid Build Coastguard Worker     paint.setShader(SkGradientShader::MakeLinear(gradPoints, gradColors, nullptr,
16*c8dee2aaSAndroid Build Coastguard Worker                     std::size(gradColors), SkTileMode::kClamp));
17*c8dee2aaSAndroid Build Coastguard Worker     SkBitmap bitmap;
18*c8dee2aaSAndroid Build Coastguard Worker     bitmap.installPixels(srcPixmap);
19*c8dee2aaSAndroid Build Coastguard Worker     SkCanvas srcCanvas(bitmap);
20*c8dee2aaSAndroid Build Coastguard Worker     srcCanvas.drawRect(SkRect::MakeWH(width, height), paint);
21*c8dee2aaSAndroid Build Coastguard Worker     canvas->drawImage(bitmap.asImage(), 0, 0);
22*c8dee2aaSAndroid Build Coastguard Worker     std::vector<int32_t> dstPixels;
23*c8dee2aaSAndroid Build Coastguard Worker     dstPixels.resize(height * width * 2);
24*c8dee2aaSAndroid Build Coastguard Worker     SkImageInfo dstInfo = srcInfo.makeColorType(kARGB_4444_SkColorType);
25*c8dee2aaSAndroid Build Coastguard Worker     srcPixmap.readPixels(dstInfo, &dstPixels.front(), width * 2);
26*c8dee2aaSAndroid Build Coastguard Worker     SkPixmap dstPixmap(dstInfo, &dstPixels.front(), width * 2);
27*c8dee2aaSAndroid Build Coastguard Worker     bitmap.installPixels(dstPixmap);
28*c8dee2aaSAndroid Build Coastguard Worker     canvas->drawImage(bitmap.asImage(), 0, 128);
29*c8dee2aaSAndroid Build Coastguard Worker }
30*c8dee2aaSAndroid Build Coastguard Worker }  // END FIDDLE
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