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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class LargePixelRef : public SkPixelRef {
public:
    LargePixelRef(const SkImageInfo& info, char* storage, size_t rowBytes)
        : SkPixelRef(info.width(), info.height(), storage, rowBytes) {
    }
    ~LargePixelRef() override {
        delete[] (char* ) this->pixels();
    }
};
class LargeAllocator : public SkBitmap::Allocator {
public:
    bool allocPixelRef(SkBitmap* bitmap) override {
        const SkImageInfo& info = bitmap->info();
        uint64_t rowBytes = info.minRowBytes64();
        uint64_t size = info.height() * rowBytes;
        char* addr = new char[size];
        if (nullptr == addr) {
            return false;
        }
        sk_sp<SkPixelRef> pr = sk_sp<SkPixelRef>(new LargePixelRef(info, addr, rowBytes));
        if (!pr) {
            return false;
        }
        bitmap->setPixelRef(std::move(pr), 0, 0);
        return true;
    }
};
​
void draw(SkCanvas* canvas) {
   LargeAllocator largeAllocator;
   SkBitmap bitmap;
   int width = 100; // make this 20000
   int height = 100; // and this 100000 to allocate 8 gigs on a 64-bit platform
   bitmap.setInfo(SkImageInfo::MakeN32(width, height, kOpaque_SkAlphaType));
   if (bitmap.tryAllocPixels(&largeAllocator)) {
       bitmap.eraseColor(0xff55aa33);
       canvas->drawImage(bitmap.asImage(), 0, 0);
   }
}