Wml::Vector2f ExpMapGenerator::ComputeSurfaceVector( ExpMapParticle * pCenterParticle,
ExpMapParticle * pNbrParticle,
ExtPlane3f & vTangentPlane,
Frame3f & vCenterWorldFrame,
Wml::Matrix2f & matFrameRotate )
{
// special case...
if ( (pNbrParticle->Position() - pCenterParticle->Position()).Length() < Wml::Mathf::EPSILON )
return pCenterParticle->SurfaceVector();
// project point into plane
Wml::Vector3f vPlanePoint = vTangentPlane.RotatePointIntoPlane( pNbrParticle->Position() );
// project point into coord system of frame
vPlanePoint -= pCenterParticle->Position();
vCenterWorldFrame.ToFrameLocal(vPlanePoint);
// now we can project into surface frame simply by dropping z (which should be 0 anyway,
// since the vector lies in the plane!)
Wml::Vector2f vSurfaceFrame( vPlanePoint.X(), vPlanePoint.Y() );
// reverse vector so it points back to current particle
vSurfaceFrame *= -1.0f;
// transform local vector into coord system of initial surface reference frame
// and add accumulated surface vector
return pCenterParticle->SurfaceVector() + (matFrameRotate * vSurfaceFrame);
}
Wml::Vector3d rms::VectorCastfd( const Wml::Vector3f & vec )
{
return Wml::Vector3d( (double)vec.X(), (double)vec.Y(), (double)vec.Z() );
}
