It's not really possible, I asked the same question here before when I was doing dot3 stuff in blitz.
The closest I came was to allign a pivot to the target vector, then tform the tangent vector by that.
vx,vy,vz=vertex position, nox,noy etc=normal.lpiv being a pivot at the vertex position and spiv, being a pivot projected in the direction of the target vector.
The closest I came was to allign a pivot to the target vector, then tform the tangent vector by that.
PointEntity lpiv1,spiv
PointEntity spiv,lpiv1
AlignToVector spiv,nox,noy,noz,0
AlignToVector spiv,nox,noy,noz,2
TFormVector2(vx,vy,vz,nox,noy,noz)
ar=128.0+(128.0*TFormedX())
ag=128.0+(128.0*TFormedY())
ab=128.0+(128.0*TFormedZ())
vx,vy,vz=vertex position, nox,noy etc=normal.lpiv being a pivot at the vertex position and spiv, being a pivot projected in the direction of the target vector.