I have the following code which produces the attached triangle picture. Does anyone know how to produce a directed edge from S_0, down and to the right, ending at D_0b? Also, join vertexes S_1 and S_1 into a single vertex or point?
The tikz-cd documentation had little info on this shape and my own results led to many compilation failures. Appreciate any guidance on creating the shape.
Thanks
Note: I'm attempting to draw a Porphyry tree.
\begin{tikzcd}[row sep=tiny]
& S_0 \arrow[dd, "\phi_1" description] \\
D_0 \arrow[ur, leftarrow] \arrow[dr, "\phi_2" description] \\
& S_1 \\
& S_1 \arrow[dd, "\phi_1" description] \\
D_1 \arrow[ur, leftarrow] \arrow[dr, "\phi_2" description] & \\
& S_2
\end{tikzcd}
& S_1 \\
.