// Intersection between 2 planes
public bool Intersect( Plane _p, Ray _ray )
{
// Check if both planes are coplanar
if ( (float) System.Math.Abs( 1.0f - _p.n.Dot(n) ) < float.Epsilon )
return false;
// Let's have fun!
float3 I = new float3();
_ray.Pos.Set( 0, 0, 0 );
_ray.Aim = n;
if ( !_p.Intersect( _ray, ref I ) )
return false;
_ray.Aim = _p.n;
if ( !_p.Intersect( _ray, ref I ) )
return false;
_ray.Pos = I;
_ray.Aim = I - _ray.Pos;
if ( !Intersect( _ray, ref I ) )
return false;
_ray.Pos = I;
// We have at least one point belonging to both planes!
_ray.Aim = n.Cross(_p.n).Normalized;
return true;
}
// Helpers
// Intersection between a plane and a ray
public bool Intersect( Ray _Ray, ref float3 _intersection )
{
float fGradient = n.Dot( _Ray.Aim );
if ( (float) System.Math.Abs( fGradient ) < float.Epsilon )
return false; // It cannot hit! (or very far away at least!)
_Ray.Length = (-d - _Ray.Pos.Dot(n)) / fGradient;
_intersection = _Ray.GetHitPos();
return true;
}
public bool IsOutsideHitBy( Ray _Ray )
{
float fDistance;
float3 HitPosition;
// Left | right intersection
if ( System.Math.Abs( _Ray.Aim.x ) > EPSILON )
{
fDistance = ( _Ray.Aim.x > 0.0f ? m_Min.x - _Ray.Pos.x : m_Max.x - _Ray.Pos.x ) / _Ray.Aim.x;
if ( fDistance >= 0.0f && fDistance <= _Ray.Length )
{
HitPosition = _Ray.Pos + _Ray.Aim * fDistance;
if ( HitPosition.y >= m_Min.y && HitPosition.y <= m_Max.y && HitPosition.z >= m_Min.z && HitPosition.z <= m_Max.z )
{
_Ray.Length = fDistance;
_Ray.Datum = _Ray.Aim.x > 0.0f ? 0 : 1;
return true;
}
}
else
_Ray.Datum = 6; // We notify the caller it didn't hit because of distance
}
// Top | bottom intersection
if ( System.Math.Abs( _Ray.Aim.y ) > EPSILON )
{
fDistance = ( _Ray.Aim.y > 0.0f ? m_Min.y - _Ray.Pos.y : m_Max.y - _Ray.Pos.y ) / _Ray.Aim.y;
if ( fDistance >= 0.0f && fDistance <= _Ray.Length )
{
HitPosition = _Ray.Pos + _Ray.Aim * fDistance;
if ( HitPosition.x >= m_Min.x && HitPosition.x <= m_Max.x && HitPosition.z >= m_Min.z && HitPosition.z <= m_Max.z )
{
_Ray.Length = fDistance;
_Ray.Datum = _Ray.Aim.y > 0.0f ? 2 : 3;
return true;
}
}
else
_Ray.Datum = 6; // We notify the caller it didn't hit because of distance
}
// Front | back intersection
if ( System.Math.Abs( _Ray.Aim.z ) > EPSILON )
{
fDistance = ( _Ray.Aim.z > 0.0f ? m_Min.z - _Ray.Pos.z : m_Max.z - _Ray.Pos.z ) / _Ray.Aim.z;
if ( fDistance >= 0.0f && fDistance <= _Ray.Length )
{
HitPosition = _Ray.Pos + _Ray.Aim * fDistance;
if ( HitPosition.x >= m_Min.x && HitPosition.x <= m_Max.x && HitPosition.y >= m_Min.y && HitPosition.y <= m_Max.y )
{
_Ray.Length = fDistance;
_Ray.Datum = _Ray.Aim.z > 0.0f ? 4 : 5;
return true;
}
}
else
_Ray.Datum = 6; // We notify the caller it didn't hit because of distance
}
return false;
}
// Intersection between 3 planes
public bool Intersect( Plane _p0, Plane _p1, ref float3 _intersection )
{
// Compute the intersection of 2 planes first, yielding a ray
Ray Hit = new Ray();
if ( !_p0.Intersect( _p1, Hit ) )
return false;
// Then compute the intersection of this ray with our plane
return Intersect( Hit, ref _intersection );
}
public bool IsInsideHitBy( Ray _Ray )
{
float fDistance;
float3 HitPosition;
// Left | right intersection
if ( System.Math.Abs( _Ray.Aim.x ) > EPSILON )
{
fDistance = ( _Ray.Aim.x < 0.0f ? m_Min.x - _Ray.Pos.x : m_Max.x - _Ray.Pos.x ) / _Ray.Aim.x;
if ( fDistance >= 0.0f && fDistance <= _Ray.Length )
{
HitPosition = _Ray.Pos + _Ray.Aim * fDistance;
if ( HitPosition.y >= m_Min.y && HitPosition.y <= m_Max.y && HitPosition.z >= m_Min.z && HitPosition.z <= m_Max.z )
{
_Ray.Length = fDistance;
_Ray.Datum = _Ray.Aim.x > 0.0f ? 1 : 0;
return true;
}
}
}
// Top | bottom intersection
if ( System.Math.Abs( _Ray.Aim.y ) > EPSILON )
{
fDistance = ( _Ray.Aim.y < 0.0f ? m_Min.y - _Ray.Pos.y : m_Max.y - _Ray.Pos.y ) / _Ray.Aim.y;
if ( fDistance >= 0.0f && fDistance <= _Ray.Length )
{
HitPosition = _Ray.Pos + _Ray.Aim * fDistance;
if ( HitPosition.x >= m_Min.x && HitPosition.x <= m_Max.x && HitPosition.z >= m_Min.z && HitPosition.z <= m_Max.z )
{
_Ray.Length = fDistance;
_Ray.Datum = _Ray.Aim.y > 0.0f ? 3 : 2;
return true;
}
}
}
// Front | back intersection
if ( System.Math.Abs( _Ray.Aim.z ) > EPSILON )
{
fDistance = ( _Ray.Aim.z < 0.0f ? m_Min.z - _Ray.Pos.z : m_Max.z - _Ray.Pos.z ) / _Ray.Aim.z;
if ( fDistance >= 0.0f && fDistance <= _Ray.Length )
{
HitPosition = _Ray.Pos + _Ray.Aim * fDistance;
if ( HitPosition.x >= m_Min.x && HitPosition.x <= m_Max.x && HitPosition.y >= m_Min.y && HitPosition.y <= m_Max.y )
{
_Ray.Length = fDistance;
_Ray.Datum = _Ray.Aim.z > 0.0f ? 5 : 4;
return true;
}
}
}
return false;
}
public bool IsHitBy( Ray _Ray )
{
// ********** TEST RAY INTERSECTION **********
bool bHitX = false, bHitY = false, bHitZ = false;
float fDistX = float.MaxValue, fDistY = float.MaxValue, fDistZ = float.MaxValue;
float3 HitPosition;
// Left right intersection
if ( System.Math.Abs( _Ray.Aim.x ) > EPSILON )
{
fDistX = ( _Ray.Aim.x > 0.0f ? System.Math.Min( m_Max.x - _Ray.Pos.x, m_Min.x - _Ray.Pos.x ) : System.Math.Max( m_Max.x - _Ray.Pos.x, m_Min.x - _Ray.Pos.x ) ) / _Ray.Aim.x;
if ( fDistX >= 0.0f )
{
HitPosition = _Ray.Pos + _Ray.Aim * fDistX;
if ( HitPosition.y >= m_Min.y && HitPosition.y <= m_Max.y && HitPosition.z >= m_Min.z && HitPosition.z <= m_Max.z )
bHitX = true;
}
}
// Top bottom intersection
if ( System.Math.Abs( _Ray.Aim.y ) > EPSILON )
{
fDistY = ( _Ray.Aim.y > 0.0f ? System.Math.Min( m_Max.y - _Ray.Pos.y, m_Min.y - _Ray.Pos.y ) : System.Math.Max( m_Max.y - _Ray.Pos.y, m_Min.y - _Ray.Pos. y) ) / _Ray.Aim.y;
if ( fDistY >= 0.0f )
{
HitPosition = _Ray.Pos + _Ray.Aim * fDistY;
if ( HitPosition.x >= m_Min.x && HitPosition.x <= m_Max.x && HitPosition.z >= m_Min.z && HitPosition.z <= m_Max.z )
bHitY = true;
}
}
// Front back intersection
if ( System.Math.Abs( _Ray.Aim.z ) > EPSILON )
{
fDistZ = ( _Ray.Aim.z > 0.0f ? System.Math.Min( m_Max.z - _Ray.Pos.z, m_Min.z - _Ray.Pos.z ) : System.Math.Max( m_Max.z - _Ray.Pos.z, m_Min.z - _Ray.Pos.z ) ) / _Ray.Aim.z;
if ( fDistZ >= 0.0f )
{
HitPosition = _Ray.Pos + _Ray.Aim * fDistZ;
if ( HitPosition.x >= m_Min.x && HitPosition.x <= m_Max.x && HitPosition.y >= m_Min.y && HitPosition.y <= m_Max.y )
bHitZ = true;
}
}
if ( !bHitX && !bHitY && !bHitZ )
return false;
if ( fDistX < fDistY )
{
if ( fDistX < fDistZ )
{
if ( fDistX > _Ray.Length )
return false; // Ray is too short!
_Ray.Length = fDistX;
_Ray.Datum = _Ray.Aim.x > 0.0f ? 1 : 0;
}
else
{
if ( fDistZ > _Ray.Length )
return false; // Ray is too short!
_Ray.Length = fDistZ;
_Ray.Datum = _Ray.Aim.z > 0.0f ? 5 : 4;
}
}
else
{
if ( fDistY < fDistZ )
{
if ( fDistY > _Ray.Length )
return false; // Ray is too short!
_Ray.Length = fDistY;
_Ray.Datum = _Ray.Aim.y > 0.0f ? 3 : 2;
}
else
{
if ( fDistZ > _Ray.Length )
return false; // Ray is too short!
_Ray.Length = fDistZ;
_Ray.Datum = _Ray.Aim.z > 0.0f ? 5 : 4;
}
}
return true;
}
public bool Intersect( Ray _Ray )
{
// ********** TEST RAY INTERSECTION (ONLY THE FACT OF INTERSECTION IS IMPORTANT THIS TIME) **********
float fDistX = float.MaxValue, fDistY = float.MaxValue, fDistZ = float.MaxValue;
float3 HitPosition;
// Left right intersection
if ( System.Math.Abs( _Ray.Aim.x ) > EPSILON )
{
fDistX = ( _Ray.Aim.x > 0.0f ? System.Math.Min( m_Max.x - _Ray.Pos.x, m_Min.x - _Ray.Pos.x ) : System.Math.Max( m_Max.x - _Ray.Pos.x, m_Min.x - _Ray.Pos.x ) ) / _Ray.Aim.x;
if ( fDistX >= 0.0f )
{
HitPosition = _Ray.Pos + _Ray.Aim * fDistX;
if ( HitPosition.y >= m_Min.y && HitPosition.y <= m_Max.y && HitPosition.z >= m_Min.z && HitPosition.z <= m_Max.z )
return true;
}
}
// Top bottom intersection
if ( System.Math.Abs( _Ray.Aim.y ) > EPSILON )
{
fDistY = ( _Ray.Aim.y > 0.0f ? System.Math.Min( m_Max.y - _Ray.Pos.y, m_Min.y - _Ray.Pos.y ) : System.Math.Max( m_Max.y - _Ray.Pos.y, m_Min.y - _Ray.Pos. y) ) / _Ray.Aim.y;
if ( fDistY >= 0.0f )
{
HitPosition = _Ray.Pos + _Ray.Aim * fDistY;
if ( HitPosition.x >= m_Min.x && HitPosition.x <= m_Max.x && HitPosition.z >= m_Min.z && HitPosition.z <= m_Max.z )
return true;
}
}
// Front back intersection
if ( System.Math.Abs( _Ray.Aim.z ) > EPSILON )
{
fDistZ = ( _Ray.Aim.z > 0.0f ? System.Math.Min( m_Max.z - _Ray.Pos.z, m_Min.z - _Ray.Pos.z ) : System.Math.Max( m_Max.z - _Ray.Pos.z, m_Min.z - _Ray.Pos.z ) ) / _Ray.Aim.z;
if ( fDistZ >= 0.0f )
{
HitPosition = _Ray.Pos + _Ray.Aim * fDistZ;
if ( HitPosition.x >= m_Min.x && HitPosition.x <= m_Max.x && HitPosition.y >= m_Min.y && HitPosition.y <= m_Max.y )
return true;
}
}
return false;
}
public Ray( Ray _Source )
{
Set( _Source );
}
// Assignment operators
public void Set( Ray _r )
{
m_Pos = _r.m_Pos; m_Aim = _r.m_Aim; m_Length = _r.m_Length; m_MarchedLength = _r.m_MarchedLength; m_Datum = _r.m_Datum;
}
