Skia Fiddle

Options

Width Height

check_box_outline_blank check_box Text Only [Use SkDebugf()]

check_box_outline_blank check_box sRGB

check_box_outline_blank check_box F16

check_box_outline_blank check_box Animation

check_box_outline_blank check_box Offscreen Render Target

Width Height Sample Count

check_box_outline_blank check_box Texturable

check_box_outline_blank check_box MipMap

This global is now defined:

GrBackendRenderTarget backEndRenderTarget;

GrBackendTexture backEndTextureRenderTarget;

Optional source image

check_box_outline_blank check_box MipMap

These globals are now defined:

SkBitmap source;
sk_sp<SkImage> image;
GrBackendTexture backEndTexture; // GPU Only.

Note:

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void draw(SkCanvas* canvas) {
    std::vector<int32_t> srcPixels;
    int rowBytes = image->width() * 4;
    int quarterWidth = image->width() / 4;
    int quarterHeight = image->height() / 4;
    srcPixels.resize(image->height() * rowBytes);
    for (int y = 0; y < 4; ++y) {
        for (int x = 0; x < 4; ++x) {
            SkPixmap pixmap(SkImageInfo::MakeN32Premul(quarterWidth, quarterHeight),
                    &srcPixels.front() + x * image->height() * quarterWidth +
                    y * quarterWidth, rowBytes);
            image->readPixels(nullptr, pixmap, x * quarterWidth, y * quarterHeight);
        }
    }
    canvas->scale(.5f, .5f);
    SkBitmap bitmap;
    bitmap.installPixels(SkImageInfo::MakeN32Premul(image->width(), image->height()),
                             &srcPixels.front(), rowBytes);
    canvas->drawImage(bitmap.asImage(), 0, 0);
}