Function fuzzyDifference

test/symbol_t.cpp:107–136

* Tests if the images are different, ignoring edges which differ in location by one pixel. * * Returns { -1, -1 } when the images are equal, * the minimum width and height when the images have different sizes, * or the coordinates of the first pixel which does not match (fuzzily). * In the second case, it uses QCOMPARE to output the sizes. * In the last case, it uses QCOMPARE to output the

 * In the last case, it uses QCOMPARE to output the pixel values.
 */
QPoint fuzzyDifference(const QImage& lhs, const QImage& rhs)
{
	if (lhs.size() != rhs.size())
	{
		auto actual_image = lhs.size();
		auto expected_image = rhs.size();
		[actual_image, expected_image](){ QCOMPARE(actual_image, expected_image); }();
		return { qMin(lhs.width(), rhs.width()), qMin(lhs.height(), rhs.height()) };
	}
	
	for (auto y = 0; y < lhs.height(); ++y)
	{
		const auto* left = reinterpret_cast<const quint32*>(lhs.scanLine(y));
		const auto* right = reinterpret_cast<const quint32*>(rhs.scanLine(y));
		for (auto x = 0; x < lhs.width(); ++x)
		{
			if (Q_UNLIKELY(left[x] != right[x])
			    && !fuzzyComparePixel(lhs, qMax(x-1, 0), qMax(y-1, 0), qMin(x+2, lhs.width()), qMin(y+2, lhs.height()), right[x]))
			{
				auto actual = QString::number(left[x], 16).toLatin1();
				auto actual_rgb = actual.constData();
				auto expected = QString::number(right[x], 16).toLatin1();
				auto expected_rgb = expected.constData();
				[actual_rgb, expected_rgb](){ QCOMPARE(actual_rgb, expected_rgb); }();
				return { x, y };
			}
		}
	}
	return { -1, -1 };
}


}  // namespace