Anh Tuan oi

Now, I criticize your formula:

We construct point Q = X(6)*c(P)*c(U)*t(cd(P, U))

I find it too much complex for X(6) is not needed.

You deduct it from the formula:

a). Barycentrics of Q = (q + r)*(v + w)/(q*w - r*v) : :

I look at ETC glossary the meaning of the point:

M = q*w - r*v::

where P = (p:q:r) and Q = (u:v:w)

M is the cross difference of P and Q only in case of using trilinears.

But here, you are using barycentrics so X(6) appareance is artificial though

needed to get a correct formula.

I don't find in ETC glossary the point M = q*w -r*v:: where P =(p:q:r) and Q

= (u:v:w) in using barycentrics;

M is simply the dual point of the line through P and Q.

Is there a special name for this point with such a projective definition?

Calling it AT(P,Q) for the moment, then we will have:

Q = c(P)*c(U)*t(AT(P,U))

Friendly

Francois

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