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////////////////////////////////////////////////////////////
//
// SFML  Simple and Fast Multimedia Library
// Copyright (C) 20072019 Laurent Gomila (laurent@sfmldev.org)
//
// This software is provided 'asis', without any express or implied warranty.
// In no event will the authors be held liable for any damages arising from the use of this software.
//
// Permission is granted to anyone to use this software for any purpose,
// including commercial applications, and to alter it and redistribute it freely,
// subject to the following restrictions:
//
// 1. The origin of this software must not be misrepresented;
// you must not claim that you wrote the original software.
// If you use this software in a product, an acknowledgment
// in the product documentation would be appreciated but is not required.
//
// 2. Altered source versions must be plainly marked as such,
// and must not be misrepresented as being the original software.
//
// 3. This notice may not be removed or altered from any source distribution.
//
////////////////////////////////////////////////////////////
template <typename T>
bool Rect<T>::intersects(const Rect<T>& rectangle, Rect<T>& intersection) const
{
// Rectangles with negative dimensions are allowed, so we must handle them correctly
// Compute the min and max of the first rectangle on both axes
T r1MinX = std::min(left, static_cast<T>(left + width));
T r1MaxX = std::max(left, static_cast<T>(left + width));
T r1MinY = std::min(top, static_cast<T>(top + height));
T r1MaxY = std::max(top, static_cast<T>(top + height));
// Compute the min and max of the second rectangle on both axes
T r2MinX = std::min(rectangle.left, static_cast<T>(rectangle.left + rectangle.width));
T r2MaxX = std::max(rectangle.left, static_cast<T>(rectangle.left + rectangle.width));
T r2MinY = std::min(rectangle.top, static_cast<T>(rectangle.top + rectangle.height));
T r2MaxY = std::max(rectangle.top, static_cast<T>(rectangle.top + rectangle.height));
// Compute the intersection boundaries
T interLeft = std::max(r1MinX, r2MinX);
T interTop = std::max(r1MinY, r2MinY);
T interRight = std::min(r1MaxX, r2MaxX);
T interBottom = std::min(r1MaxY, r2MaxY);
// If the intersection is valid (positive non zero area), then there is an intersection
if ((interLeft < interRight) && (interTop < interBottom))
{
intersection = Rect<T>(interLeft, interTop, interRight  interLeft, interBottom  interTop);
return true;
}
else
{
intersection = Rect<T>(0, 0, 0, 0);
return false;
}
}
 