kicad/libs/kimath/include/geometry/circle.h

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4.3 KiB
C++

/*
* This program source code file is part of KiCad, a free EDA CAD application.
*
* Copyright (C) 2021 Roberto Fernandez Bautista <roberto.fer.bau@gmail.com>
* Copyright (C) 2021 KiCad Developers, see AUTHORS.txt for contributors.
*
* This program is free software: you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation, either version 3 of the License, or (at your
* option) any later version.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef __CIRCLE_H
#define __CIRCLE_H
#include <math/vector2d.h> // for VECTOR2I
#include <vector> // for std::vector
class SEG;
/**
* Represent basic circle geometry with utility geometry functions.
*/
class CIRCLE
{
public:
CIRCLE();
CIRCLE( const VECTOR2I& aCenter, int aRadius );
CIRCLE( const CIRCLE& aOther );
/**
* Construct this circle such that it is tangent to the given segments and passes through the
* given point, generating the solution which can be used to fillet both segments.
*
* The caller is responsible for ensuring it is providing a solvable problem. This function will
* assert if this is not the case.
*
* @param aLineA is the first tangent line. Treated as an infinite line except for the purpose
* of selecting the solution to return.
* @param aLineB is the second tangent line. Treated as an infinite line except for the purpose
* of selecting the solution to return.
* @param aP is the point to pass through.
* @return this circle.
*/
CIRCLE& ConstructFromTanTanPt( const SEG& aLineA, const SEG& aLineB, const VECTOR2I& aP );
/**
* Return true if aP is on the circumference of this circle. Note that there is an accepted
* margin of error of SHAPE::MIN_PRECISION_IU to account for integer rounding errors.
*
* @param aP A point to test
* @return true if aP is on the circumference.
*/
bool Contains( const VECTOR2I& aP ) const;
/**
* Compute the point on the circumference of the circle that is the closest to aP.
*
* In other words: finds the intersection point of this circle and a line that passes through
* both this circle's center and aP.
*
* @param aP.
* @return nearest point to aP.
*/
VECTOR2I NearestPoint( const VECTOR2I& aP ) const;
/**
* Compute the intersection points between this circle and \a aCircle.
*
* @param aCircle The other circle to intersect with this.
* @return std::vector containing:
* - 0 elements if the circles do not intersect.
* - 1 element if the circles are tangent.
* - 2 elements if the circles intersect.
*/
std::vector<VECTOR2I> Intersect( const CIRCLE& aCircle ) const;
/**
* Compute the intersection points between this circle and \a aSeg.
*
* @param aSeg The segment to intersect with this circle (end points ignored).
* @return std::vector containing up to two intersection points.
*/
std::vector<VECTOR2I> Intersect( const SEG& aSeg ) const;
/**
* Compute the intersection points between this circle and aLine.
*
* @param aLine The line to intersect with this circle (end points ignored).
* @return std::vector containing:
* - 0 elements if there is no intersection.
* - 1 element if the line is tangent to the circle.
* - 2 elements if the line intersects the circle.
*/
std::vector<VECTOR2I> IntersectLine( const SEG& aLine ) const;
/**
* Check whether point aP is inside this circle.
*
* @param aP The point to check.
* @return true if the point is inside, false otherwise.
*/
bool Contains( const VECTOR2I& aP );
int Radius; ///< Public to make access simpler
VECTOR2I Center; ///< Public to make access simpler
};
#endif // __CIRCLE_H