zxing-cpp: strip to core library only (remove tests/wrappers/examples/docs); .gitignore: fix /core to allow zxing-cpp/core/ dir

tools/chatgui/zxing-cpp/core/src/ResultPoint.cpp

@@ -0,0 +1,20 @@
+/*
+* Copyright 2016 Nu-book Inc.
+* Copyright 2016 ZXing authors
+*/
+// SPDX-License-Identifier: Apache-2.0
+
+#include "ResultPoint.h"
+
+#include <cmath>
+
+namespace ZXing {
+
+float ResultPoint::Distance(int aX, int aY, int bX, int bY)
+{
+	auto dx = static_cast<float>(aX - bX);
+	auto dy = static_cast<float>(aY - bY);
+	return std::sqrt(dx * dx + dy * dy);
+}
+
+} // ZXing