#pragma once
#include "Vector3.h"
// fwd:
class cWorld;
// tolua_begin
class cTracer
{
public:
/// Contains the position of the block that caused the collision
Vector3f BlockHitPosition;
/// Contains which face was hit
Vector3f HitNormal;
/// Contains the exact position where a collision occured. (BlockHitPosition + Offset on block)
Vector3f RealHit;
cTracer(cWorld * a_World);
~cTracer();
/// Determines if a collision occures along a line. Returns true if a collision occurs.
bool Trace(const Vector3f & a_Start, const Vector3f & a_Direction, int a_Distance)
{
return Trace(a_Start, a_Direction, a_Distance, false);
}
/// Determines if a collision occures along a line. Returns true if a collision occurs.
/// When a_LineOfSight is true, we don't use the standard collision detection rules. Instead we use
/// the rules for monster vision. E.g. Only water and air do not block vision.
/// a_Distance is the number of iterations (blocks hits) that are tested.
bool Trace(const Vector3f & a_Start, const Vector3f & a_Direction, int a_Distance, bool a_LineOfSight);
private:
/// Preps Tracer object for call of Trace function. Only used internally.
void SetValues( const Vector3f & a_Start, const Vector3f & a_Direction);
/// Calculates where on the block a collision occured, if it does occur
/// Returns 0 if no intersection occured
/// Returns 1 if an intersection occured at a single point
/// Returns 2 if the line segment lies in the plane being checked
int intersect3D_SegmentPlane( const Vector3f & a_Origin, const Vector3f & a_End, const Vector3f & a_PlanePos, const Vector3f & a_PlaneNormal);
/// Determines which face on the block a collision occured, if it does occur
/// Returns 0 if the block is air, water or no collision occured
/// Return 1 through 6 for the following block faces, repectively: -x, -z, x, z, y, -y
int GetHitNormal( const Vector3f & start, const Vector3f & end, const Vector3i & a_BlockPos);
/// Signum function
int SigNum( float a_Num);
cWorld* m_World;
Vector3f m_NormalTable[6];
Vector3f dir;
Vector3f tDelta;
Vector3i pos;
Vector3i end1;
Vector3i step;
Vector3f tMax;
};
// tolua_end
