Tools/TestWebKitAPI/cocoa/CGImagePixelReader.h

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#pragma once

#include <CoreGraphics/CoreGraphics.h>
#include <wtf/Forward.h>
#include <wtf/RetainPtr.h>

namespace WebCore {
class Color;
}

namespace TestWebKitAPI {

// FIXME: We can unify most of this helper class with the logic in `TestPDFPage::colorAtPoint`, and deploy this
// helper class in several other tests that read pixel data from CGImages.
class CGImagePixelReader {
    WTF_DEPRECATED_MAKE_FAST_ALLOCATED(CGImagePixelReader); WTF_MAKE_NONCOPYABLE(CGImagePixelReader);
public:
    CGImagePixelReader(CGImageRef);

    bool isTransparentBlack(unsigned x, unsigned y) const;
    WebCore::Color at(unsigned x, unsigned y) const;
    String cssColorAt(unsigned x, unsigned y) const;

    unsigned width() const { return m_width; }
    unsigned height() const { return m_height; }

    static constexpr auto defaultWebViewSamplingInterval { 100 };

private:
    unsigned m_width { 0 };
    unsigned m_height { 0 };
    RetainPtr<CGContextRef> m_context;
};

} // namespace TestWebKitAPI