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/*--------------------------------------	Intersection--------------------------------------*/#define GW_NO_CROSS	0#define GW_CROSS	1#define	GW_PARREL	2int Intersect(const gwSegment& _first, const gwSegment& _second, gwVector& _result){	gwVector _alpha(_first.ex - _first.sx, _first.ey - _first.sy);		// First Direction	gwVector _beta(_second.sx - _second.ex, _second.sy - _second.ey);	// Second Direction Flipped	_result = gwVector();	//----------------------------------------	//	X Bounding Check	//----------------------------------------	if(_alpha.x > 0)	// Ensure Work is Left to Right	{		if(_beta.x > 0)		{			if((_first.ex < _second.ex) || (_second.sx < _first.sx))		return GW_NO_CROSS;		}		else		{			if((_first.ex < _second.sx) || (_second.ex < _first.sx))		return GW_NO_CROSS;		}	}	else	{		if(_beta.x > 0)		{			if((_first.sx < _second.ex) || (_second.sx < _first.ex))		return GW_NO_CROSS;		}		else		{			if((_first.sx < _second.sx) || (_second.ex < _first.ex))		return GW_NO_CROSS;		}	}	//----------------------------------------	//	Y Bounding Check	//----------------------------------------	if(_alpha.y > 0)	// Ensure Work is Left to Right	{		if(_beta.y > 0)		{			if((_first.ey < _second.ey) || (_second.sy < _first.sy))		return GW_NO_CROSS;		}		else		{			if((_first.ey < _second.sy) || (_second.ey < _first.sy))		return GW_NO_CROSS;		}	}	else	{		if(_beta.y > 0)		{			if((_first.sy < _second.ey) || (_second.sy < _first.ey))		return GW_NO_CROSS;		}		else		{			if((_first.sy < _second.sy) || (_second.ey < _first.ey))		return GW_NO_CROSS;		}	}	gwVector _charlie(_first.sx - _second.sx, _first.sy - _second.sy);		//-----------------------------------	//	Parrell Test	//-----------------------------------	float _dem = (_alpha.y * _beta.x) - (_alpha.x * _beta.y);	if(fabsf(_dem) < 0.00000001f) return GW_PARREL;	//-----------------------------------	//	Alpha Test	//-----------------------------------	float _an = (_beta.y * _charlie.x) - (_beta.x * _charlie.y);	if(_dem > 0)	{		if(_an < 0 || _an > _dem) return GW_NO_CROSS;	}	else 	{		if(_an > 0 || _an < _dem) return GW_NO_CROSS;	}	//-----------------------------------	//	Beta Test	//-----------------------------------	float _bn = (_alpha.x * _charlie.y) - (_alpha.y * _charlie.x);	if(_dem > 0)	{		if(_bn < 0 || _bn > _dem) return GW_NO_CROSS;	}	else 	{		if(_bn > 0 || _bn < _dem) return GW_NO_CROSS;	}	//-----------------------------------	//	They Do Intersect	//	Calc Point	//-----------------------------------	gwVector _num(_an*_alpha.x);	gwVector _offset;	_offset.x = (((_num.x > 0)&&(_dem > 0)) || ((_num.x < 0)&&(_dem < 0))) ? (_dem / 2.0f) : -(_dem/2.0f);	_offset.y = (((_num.y > 0)&&(_dem > 0)) || ((_num.y < 0)&&(_dem < 0))) ? (_dem / 2.0f) : -(_dem/2.0f);	_result = gwVector(_first.sx,_first.sy) + (_num + _offset) / _dem;	return GW_CROSS;}