Commit c87b1365 authored by Tomasz Włostowski's avatar Tomasz Włostowski
Browse files

geometry: new methods and fixes in SEG class

parent da8e9e9b

common/geometry/seg.cpp

+2 −0
Original line number Diff line number Diff line
@@ -35,6 +35,7 @@ bool SEG::PointCloserThan( const VECTOR2I& aP, int aDist ) const 
{

    VECTOR2I d = B - A;

    ecoord dist_sq = (ecoord) aDist * aDist;

    ecoord dist_sq_thr = (ecoord) (aDist + 1) * (aDist + 1);



    SEG::ecoord l_squared = d.Dot( d );

    SEG::ecoord t = d.Dot( aP - A );
@@ -60,6 +61,7 @@ bool SEG::PointCloserThan( const VECTOR2I& aP, int aDist ) const 


        if( num > ( dist_sq + 100 ) )

            return false;



        else if( num < ( dist_sq - 100 ) )

            return true;

    }

include/geometry/seg.h

+57 −8
Original line number Diff line number Diff line
@@ -206,6 +206,13 @@ public: 
        return sqrt( SquaredDistance( aP ) );

    }



    void CanonicalCoefs ( ecoord& qA, ecoord& qB, ecoord& qC) const

    {

        qA = A.y - B.y;

        qB = B.x - A.x;

        qC = -qA * A.x - qB * A.y;

    }



    /**

     * Function Collinear()

     *
@@ -215,9 +222,8 @@ public: 
     */

    bool Collinear( const SEG& aSeg ) const

    {

        ecoord qa = A.y - B.y;

        ecoord qb = B.x - A.x;

        ecoord qc = -qa * A.x - qb * A.y;

        ecoord qa, qb, qc;

        CanonicalCoefs ( qa, qb, qc );

        

        ecoord d1 = std::abs( aSeg.A.x * qa + aSeg.A.y * qb + qc );

        ecoord d2 = std::abs( aSeg.B.x * qa + aSeg.B.y * qb + qc );
@@ -225,6 +231,29 @@ public: 
        return ( d1 <= 1 && d2 <= 1 );

    }



    bool ApproxCollinear( const SEG& aSeg ) const

    {

        ecoord p, q, r;

        CanonicalCoefs ( p, q, r );

    

        ecoord dist1 = ( p * aSeg.A.x + q * aSeg.A.y + r ) / sqrt( p * p + q * q );     

        ecoord dist2 = ( p * aSeg.B.x + q * aSeg.B.y + r ) / sqrt( p * p + q * q );     



        return std::abs(dist1) <= 1 && std::abs(dist2) <= 1;

    }



    bool ApproxParallel ( const SEG& aSeg ) const

    {

        ecoord p, q, r;

        CanonicalCoefs ( p, q, r );

        

        ecoord dist1 = ( p * aSeg.A.x + q * aSeg.A.y + r ) / sqrt( p * p + q * q );     

        ecoord dist2 = ( p * aSeg.B.x + q * aSeg.B.y + r ) / sqrt( p * p + q * q );     



        return std::abs(dist1 - dist2) <= 1;

    }





    bool Overlaps( const SEG& aSeg ) const

    {

        if( aSeg.A == aSeg.B ) // single point corner case
@@ -262,6 +291,8 @@ public: 
        return ( A - B ).SquaredEuclideanNorm();

    }



    ecoord TCoef ( const VECTOR2I& aP ) const;



    /**

     * Function Index()

     *
@@ -277,7 +308,11 @@ public: 


    bool PointCloserThan( const VECTOR2I& aP, int aDist ) const;



//    friend std::ostream& operator<<( std::ostream& stream, const SEG& aSeg );

    void Reverse()

    {

        std::swap ( A, B );

    }



private:

    bool ccw( const VECTOR2I& aA, const VECTOR2I& aB, const VECTOR2I &aC ) const;
@@ -288,9 +323,18 @@ private: 


inline VECTOR2I SEG::LineProject( const VECTOR2I& aP ) const

{

    // fixme: numerical errors for large integers

    assert( false );

    return VECTOR2I( 0, 0 );

    VECTOR2I d = B - A;

    ecoord l_squared = d.Dot( d );



    if( l_squared == 0 )

        return A;



    ecoord t = d.Dot( aP - A );



    int xp = rescale( t, (ecoord)d.x, l_squared );

    int yp = rescale( t, (ecoord)d.y, l_squared );



    return A + VECTOR2I( xp, yp );

}
@@ -305,6 +349,11 @@ inline int SEG::LineDistance( const VECTOR2I& aP, bool aDetermineSide ) const 
    return aDetermineSide ? dist : abs( dist );

}



inline SEG::ecoord SEG::TCoef ( const VECTOR2I& aP ) const

{

    VECTOR2I d = B - A;

    return d.Dot ( aP - A);

}



inline const VECTOR2I SEG::NearestPoint( const VECTOR2I& aP ) const

{