F:/My Projects/LSEngine/Modules/LSMathLib/Src/Triangle/LSMTriangle3.h

#ifndef __LSM_TRIANGLE3_H__
#define __LSM_TRIANGLE3_H__

#include "../LSMMathLib.h"
#include "../Vector/LSMVector3.h"

namespace lsm {

        class CTriangle3 {
                // All is public.  This class has no secrets.
        public :
                // == Various constructors.
                LSE_INLINE LSE_CALLCTOR                                         CTriangle3();
                LSE_INLINE LSE_CALLCTOR                                         CTriangle3( const CTriangle3 &_tTri );
                LSE_INLINE LSE_CALLCTOR                                         CTriangle3( const CVector3 &_vA, const CVector3 &_vB, const CVector3 &_vC );


                // == Operators.
                LSE_INLINE CVector3 & LSE_FCALL                         operator [] ( LSUINT32 _ui32I );

                LSE_INLINE const CVector3 & LSE_FCALL           operator [] ( LSUINT32 _ui32I ) const;

                LSE_INLINE bool LSE_FCALL                                       operator == ( const CTriangle3 &_tTri ) const;

                LSE_INLINE bool LSE_FCALL                                       operator != ( const CTriangle3 &_tTri ) const;


                // == Functions.
                LSE_INLINE LSVOID LSE_FCALL                                     ReverseOrder();

                LSE_INLINE const CVector3 & LSE_FCALL           A() const;

                LSE_INLINE const CVector3 & LSE_FCALL           B() const;

                LSE_INLINE const CVector3 & LSE_FCALL           C() const;

                LSVOID LSE_FCALL                                                        Barycentric( const CVector3 &_vPoint,
                        LSREAL &_fU, LSREAL &_fV, LSREAL &_fW ) const;



                // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
                // DISTANCE TESTS
                // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
                // == Points.
                CVector3 LSE_FCALL                                                      ClosestPointToPoint( const CVector3 &_vPoint ) const;
                
                LSREAL LSE_FCALL                                                        GetSqDistFromPoint( const CVector3 &_vPoint ) const;

                LSBOOL LSE_FCALL                                                        PointIsInTriangle( const CVector3 &_vPoint ) const;


                // == Members.
#pragma pack( push, 1 )
                CVector3                                                                        a;
                CVector3                                                                        b;
                CVector3                                                                        c;
#pragma pack( pop )


        protected :
                // == Functions.
                LSE_INLINE static LSREAL LSE_FCALL                      TriArea2D( LSREAL _fX1, LSREAL _fY1,
                        LSREAL _fX2, LSREAL _fY2,
                        LSREAL _fX3, LSREAL _fY3 );
        };


        // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
        // DEFINITIONS
        // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
        // == Various constructors.
        LSE_INLINE LSE_CALLCTOR CTriangle3::CTriangle3() {}
        LSE_INLINE LSE_CALLCTOR CTriangle3::CTriangle3( const CTriangle3 &_tTri ) :
                a( _tTri.a ),
                b( _tTri.b ),
                c( _tTri.c ) {
        }
                LSE_INLINE LSE_CALLCTOR CTriangle3::CTriangle3( const CVector3 &_vA, const CVector3 &_vB, const CVector3 &_vC ) :
                a( _vA ),
                b( _vB ),
                c( _vC ) {
        }

        // == Operators.
        LSE_INLINE CVector3 & LSE_FCALL CTriangle3::operator [] ( LSUINT32 _ui32I ) { return reinterpret_cast<CVector3 *>(this)[_ui32I]; }

        LSE_INLINE const CVector3 & LSE_FCALL CTriangle3::operator [] ( LSUINT32 _ui32I ) const { return reinterpret_cast<const CVector3 *>(this)[_ui32I]; }

        LSE_INLINE bool LSE_FCALL CTriangle3::operator == ( const CTriangle3 &_tTri ) const {
                return a == _tTri.a && b == _tTri.b && c == _tTri.c;
        }

        LSE_INLINE bool LSE_FCALL CTriangle3::operator != ( const CTriangle3 &_tTri ) const {
                return a != _tTri.a || b != _tTri.b || c != _tTri.c;
        }

        // == Functions.
        LSE_INLINE LSVOID LSE_FCALL CTriangle3::ReverseOrder() {
                CMathLib::Swap( a, c );
        }

        LSE_INLINE const CVector3 & LSE_FCALL CTriangle3::A() const { return a; }

        LSE_INLINE const CVector3 & LSE_FCALL CTriangle3::B() const { return b; }

        LSE_INLINE const CVector3 & LSE_FCALL CTriangle3::C() const { return c; }

        LSE_INLINE LSREAL LSE_FCALL CTriangle3::TriArea2D( LSREAL _fX1, LSREAL _fY1,
                LSREAL _fX2, LSREAL _fY2,
                LSREAL _fX3, LSREAL _fY3 ) {
                return (_fX1 - _fX2) * (_fY2 - _fY3) - (_fX2 - _fX3) * (_fY1 - _fY2);
        }

}       // namespace lsm

#endif  // __LSM_TRIANGLE3_H__