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mirror of https://gitlab.com/kicad/code/kicad.git synced 2024-11-28 00:31:20 +00:00
kicad/libs/kimath/include/geometry/vector_utils.h
John Beard 95beedb612 Dogbones: add slots for acute angles
It's actually not as hard as I thought, though
surely has wierd edge cases which users might need to
handle manually.
2024-09-22 13:45:19 +01:00

152 lines
4.2 KiB
C++

/*
* This program source code file is part of KiCad, a free EDA CAD application.
*
* Copyright (C) 2024 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/>.
*/
#include <math/vector2d.h>
class SEG;
namespace KIGEOM
{
/**
* @file vector_utils.h
*
* Supplemental functions for working with vectors and
* simple objects that interact with vectors.
*/
/*
* Determine if a point is in a given direction from another point.
*
* This returns true if the vector from aFrom to aPoint is within
* 90 degrees of aDirection.
*
* ------> aDirection
*
* /-- aFrom
* O /-- aPoint
* O
*
* If the point is perpendicular to the direction, it is considered
* to NOT be in the direction (e.g. both the direction and the
* reversed direction would return false).
*
* @param aPoint The point to test.
* @param aDirection The direction vector.
* @param aFrom The point to test from.
*
* @return true if the point is in the direction.
*/
template <typename T>
bool PointIsInDirection( const VECTOR2<T>& aPoint, const VECTOR2<T>& aDirection,
const VECTOR2<T>& aFrom )
{
return ( aPoint - aFrom ).Dot( aDirection ) > 0;
}
/**
* Check that the two given points are in the same direction from some other point.
*
* I.e. the vectors from aFrom to aPointA and aFrom to aPointB are within 90 degrees.
*/
template <typename T>
bool PointsAreInSameDirection( const VECTOR2<T>& aPointA, const VECTOR2<T>& aPointB,
const VECTOR2<T>& aFrom )
{
return PointIsInDirection( aPointB, aPointA - aFrom, aFrom );
}
/**
* Determine if a segment's vector is within 90 degrees of a given direction.
*/
bool SegIsInDirection( const SEG& aSeg, const VECTOR2I& aDirection );
/**
* Determine if a point projects onto a segment.
*
* /--- projects /--- does not project
* o o
* | |
* |<------------>| x
* aSeg
*/
bool PointProjectsOntoSegment( const VECTOR2I& aPoint, const SEG& aSeg );
/**
* Get the ratio of the vector to a point from the segment's start,
* compared to the segment's length.
*
* /--- aPoint
* A<---+-------->B <-- Length L
* | |
* >|----|<-- Length R
*
* The point doesn't have to lie on the segment.
*/
double GetLengthRatioFromStart( const VECTOR2I& aPoint, const SEG& aSeg );
/**
* Get the ratio of the vector to a point projected onto a segment
* from the start, relative to the segment's length.
*
* /--- projects
* o
* |
* A<---+-------->B <-- Length L
* | |
* >|----|<-- Length R
*
* The ratio is R / L. IF 0, the point is at A. If 1, the point is at B.
* It assumes the point projects onto the segment.
*/
double GetProjectedPointLengthRatio( const VECTOR2I& aPoint, const SEG& aSeg );
/**
* Get the nearest end of a segment to a point.
*
* If equidistant, the start point is returned.
*/
const VECTOR2I& GetNearestEndpoint( const SEG& aSeg, const VECTOR2I& aPoint );
/**
* Round a vector to the nearest grid point in any direction.
*/
VECTOR2I RoundGrid( const VECTOR2I& aVec, int aGridSize );
/**
* Round a vector to the nearest grid point in the NW direction.
*
* This means x and y are both rounded downwards (regardless of sign).
*/
VECTOR2I RoundNW( const VECTOR2I& aVec, int aGridSize );
/**
* Round a vector to the nearest grid point in the SE direction.
*
* This means x and y are both rounded upwards (regardless of sign).
*/
VECTOR2I RoundSE( const VECTOR2I& aVec, int aGridSize );
} // namespace KIGEOM