Here is the solution for the location of points showed in the picture. For other cases, the location of the solution will be similar. Prove that for any selected point D quadrilateral XOYZ is inscribed. Then ∠XZY=180∘−2∠A, so doesn't depend on D.
From the statement of the problem we have that circles △BXD and △DYC are tangent to lines AB and AC. Denote these circles as w1 and w2, and their centers are O1 and O2. Let K be the second point of intersection of these circles other than D (see figure below).

Then
∠BKC=∠BKD+∠DKC=∠B+∠C=180∘−∠A,
so K is on the circumcircle △ABC. Also we have
∠XKY=∠XKD+∠DKY=∠XBD+∠DCY=180∘−∠XOY,
so quadrilateral XOYK is inscribed. Because AZ is the diameter of the big circle, we have that AB⊥BZ, so O1 is on line BZ. Similarly O2 is on the line CZ. We prove that O1, O2 are on the circle OXKY. Indeed,
∠XO1K=2∠XBK=2(90∘−21∠BOK)=180∘−∠XOK,
Similarly for point O2. Now we prove that point Z is on circle OXKY, which will finish the solution.
For this purpose we prove that ∠O1ZC+∠O1KO2=180∘. Indeed,
∠O1KO2=∠O1KD+∠DKO2=90∘−∠DBK+90∘−∠DCK=180∘−∠A=90∘−∠BOC
=∠BZC=180∘−∠O1ZC10th form10th form