line_2d.inl

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/** @file
 *  @author Bram de Greve (bramz@users.sourceforge.net)
 *  @author Tom De Muer (tomdemuer@users.sourceforge.net)
 *
 *  *** BEGIN LICENSE INFORMATION ***
 *  
 *  The contents of this file are subject to the Common Public Attribution License 
 *  Version 1.0 (the "License"); you may not use this file except in compliance with 
 *  the License. You may obtain a copy of the License at 
 *  http://lass.sourceforge.net/cpal-license. The License is based on the 
 *  Mozilla Public License Version 1.1 but Sections 14 and 15 have been added to cover 
 *  use of software over a computer network and provide for limited attribution for 
 *  the Original Developer. In addition, Exhibit A has been modified to be consistent 
 *  with Exhibit B.
 *  
 *  Software distributed under the License is distributed on an "AS IS" basis, WITHOUT 
 *  WARRANTY OF ANY KIND, either express or implied. See the License for the specific 
 *  language governing rights and limitations under the License.
 *  
 *  The Original Code is LASS - Library of Assembled Shared Sources.
 *  
 *  The Initial Developer of the Original Code is Bram de Greve and Tom De Muer.
 *  The Original Developer is the Initial Developer.
 *  
 *  All portions of the code written by the Initial Developer are:
 *  Copyright (C) 2004-2007 the Initial Developer.
 *  All Rights Reserved.
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 *
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 *  GNU General Public License Version 2 or later (the GPL), in which case the 
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 *  *** END LICENSE INFORMATION ***
 */



#ifndef LASS_GUARDIAN_OF_INCLUSION_PRIM_LINE_2D_INL
#define LASS_GUARDIAN_OF_INCLUSION_PRIM_LINE_2D_INL




#include "line_2d.h"



namespace lass
{

namespace prim
{

template<typename T, typename EP, typename NP>
Line2D<T, EP, NP>::Line2D():
    TImpl()
{
}




template<typename T, typename EP, typename NP>
Line2D<T, EP, NP>::Line2D(const TPoint& iSupport, const TPoint& iPoint):
    TImpl(iSupport, iPoint)
{
}



template<typename T, typename EP, typename NP>
Line2D<T, EP, NP>::Line2D(const TPoint& iSupport, const TVector& iDirection):
    TImpl(iSupport, iDirection)
{
}



template<typename T, typename EP, typename NP>
Line2D<T, EP, NP>::Line2D(const TVector& iNormal, const TPoint& iSupport):
    TImpl(iNormal, iSupport)
{
}



template<typename T, typename EP, typename NP>
Line2D<T, EP, NP>::Line2D(const TVector& iNormal, TParam iD):
    TImpl(iNormal, iD)
{
}



/** Return on what side a point is located.
 */
template<typename T, typename EP, typename NP>
const Side Line2D<T, EP, NP>::classify(const TPoint& iPoint) const
{
    const TValue eq = this->equation(iPoint);
    return eq > TNumTraits::zero ? sFront : (eq < TNumTraits::zero ? sBack : sSurface);
}



/** Return signed distance of point to line.
 *  negative value means point is in the back.
 */
template<typename T, typename EP, typename NP>
const typename Line2D<T, EP, NP>::TValue
Line2D<T, EP, NP>::signedDistance(const TPoint& iPoint) const
{
    return NP::divideByNorm(this->equation(iPoint), this->normal());
}



/** Return signed distance of point to line.
 *  negative value means point is in the back.
 */
template<typename T, typename EP, typename NP>
const typename Line2D<T, EP, NP>::TValue
Line2D<T, EP, NP>::squaredDistance(const TPoint& iPoint) const
{
    return num::sqr(this->signedDistance(iPoint));
}



/** Return on what side a point is located.
 */
template<typename T, typename EP, typename NP>
const Side Line2D<T, EP, NP>::classify(const TPoint& iPoint, TParam iRelativeTolerance) const
{
    const TValue eq = this->equation(iPoint, iRelativeTolerance);
    return eq > TNumTraits::zero ? sFront : (eq < TNumTraits::zero ? sBack : sSurface);
}



/** Return signed distance of point to line.
 *  negative value means point is in the back.
 */
template<typename T, typename EP, typename NP>
const typename Line2D<T, EP, NP>::TValue
Line2D<T, EP, NP>::signedDistance(const TPoint& iPoint, TParam iRelativeTolerance) const
{
    return NP::divideByNorm(this->equation(iPoint, iRelativeTolerance), this->normal());
}



/** Return signed distance of point to line.
 *  negative value means point is in the back.
 */
template<typename T, typename EP, typename NP>
const typename Line2D<T, EP, NP>::TValue
Line2D<T, EP, NP>::squaredDistance(const TPoint& iPoint, TParam iRelativeTolerance) const
{
    return num::sqr(this->signedDistance(iPoint, iRelativeTolerance));
}



// --- protected -----------------------------------------------------------------------------------



// --- private -------------------------------------------------------------------------------------



// --- free ----------------------------------------------------------------------------------------

/** absolute distance between point and line.
 *  @relates Line2D
 *  @param iA   point
 *  @param iB   line
 *  @return absolute distance.
 */
template <typename T, class EP, class NP>
T distance(const Point2D<T>& iA, const Line2D<T, EP, NP>& iB)
{
    return num::abs(iB.signedDistance(iA));
}



/** absolute distance between two lines
 *  @relates Line2D
 *  @param iA   line A
 *  @param iB   line B
 *  @return absolute distance.
 */
template <typename T, class EPa, class NPa, class EPb, class NPb>
T distance(const Line2D<T, EPa, NPa>& iA, const Line2D<T, EPb, NPb>& iB)
{
    LASS_ASSERT(iA.isValid() && iB.isValid());

    typedef typename Line2D<T, EPa, NPa>::TNumTraits TNumTraits;

    if (perpDot(iA.direction(), iB.direction()) == TNumTraits::zero)
    {
        return num::abs(iA.signedDistance(iB.support())); // parallel
    }
    else
    {
        return TNumTraits::zero; // intersecting
    }
}



/** intersection of two lines
 *  @relates Line2D
 *  @param iA   line A
 *  @param iB   line B
 *  @param oTa  parameter of intersection point on line A
 *  @param oTb  parameter of intersection point on line B
 *  @return @arg rNone      the lines don't intersect, they have no points in common.
 *                          @a oTa and @a oTb are not assigned.
 *          @arg rOne       both lines have exactly one point in common.
 *                          @a oTa and @a oTb contain parameters of intersection point.
 *          @arg rInfinite  the lines are coincident, they have all points in common.
 *                          @a oTa and @a oTb are not assigned.
 */
template <typename T, class EPa, class NPa, class EPb, class NPb>
Result intersect(const Line2D<T, EPa, NPa>& iA, const Line2D<T, EPb, NPb>& iB,
                 T& oTa, T& oTb)
{
    LASS_ASSERT(iA.isValid() && iB.isValid());

    typedef typename Line2D<T, EPa, NPa>::TVector TVector;
    typedef typename Line2D<T, EPa, NPa>::TValue TValue;
    typedef typename Line2D<T, EPa, NPa>::TNumTraits TNumTraits;

    const TVector dirA(iA.direction());
    const TVector dirB(iB.direction());

    const TValue denominator = -perpDot(dirA, dirB);
    if (denominator == TNumTraits::zero)
    {
        switch (iA.classify(iB.support()))
        {
        case sFront:
        case sBack:
            return rNone; // parallel
        case sSurface:
            return rInfinite; // coincident
        default:
            return rInvalid;
        }
    }
    else
    {
        const TVector difference = iB.support() - iA.support();
        oTa = -perpDot(difference, dirB) / denominator;
        oTb = perpDot(dirA, difference) / denominator;
        return rOne; // intersecting
    }
}



/** intersection of two lines
 *  @relates Line2D
 *  @param iA   line A
 *  @param iB   line B
 *  @param oPoint   intersection point
 *  @return @arg rNone      the lines don't intersect, they have no points in common.
 *                          @a oPoint is not assigned.
 *          @arg rOne       both lines have exactly one point in common.
 *                          @a oPoint contains intersection point.
 *          @arg rInfinite  the lines are coincident, they have all points in common.
 *                          @a oPoint is not assigned.
 */
template <typename T, class EPa, class NPa, class EPb, class NPb>
Result intersect(const Line2D<T, EPa, NPa>& iA, const Line2D<T, EPb, NPb>& iB,
                 Point2D<T>& oPoint)
{
    T tA;
    T tB;
    Result result = intersect(iA, iB, tA, tB);
    if (result == rOne)
    {
        oPoint = (iA.point(tA) + iB.point(tB)).affine(); // take average for more stable point.
    }
    return result;
}



/** @relates Line2D
 */
template <typename T>
io::XmlOStream& operator<<(io::XmlOStream& ioOStream, const Line2D<T, Cartesian>& iLine)
{
    LASS_ENFORCE_STREAM(ioOStream)
        << "<Line2D>\n"
        << "<normal>" << iLine.normal() << "</normal>\n"
        << "<d>" << iLine.d() << "</d>\n"
        << "</Line2D>\n";

    return ioOStream;
}



/** @relates Line2D
 */
template <typename T>
io::XmlOStream& operator<<(io::XmlOStream& ioOStream, const Line2D<T, Parametric>& iLine)
{
    LASS_ENFORCE_STREAM(ioOStream)
        << "<Line2D>\n"
        << "<support>" << iLine.support() << "</support>\n"
        << "<direction>" << iLine.direction() << "</direction>\n"
        << "</Line2D>\n";

    return ioOStream;
}



/** @relates Line2D
 */
template <typename T>
io::XmlOStream& operator<<(io::XmlOStream& ioOStream, const Line2D<T, Combined>& iLine)
{
    LASS_ENFORCE_STREAM(ioOStream)
        << "<Line2D>\n"
        << "<support>" << iLine.support() << "</support>\n"
        << "<direction>" << iLine.direction() << "</direction>\n"
        << "<normal>" << iLine.normal() << "</normal>\n"
        << "<d>" << iLine.d() << "</d>\n"
        << "</Line2D>\n";

    return ioOStream;
}



}

}

#endif

// EOF