Venting new bathroom question

[Mjricha]

Hello all! I've been reading the forum alot lately trying to answer my questions without having to add another one, but I have a question about venting a new bathroom. From what I've read it looks like you can only wet 2 things, and the third thing has to be dry vented. So I'm putting a bathroom into our garage (concrete floor) and I just wanted to check and make sure this was correct before I started tearing up the floor. As I have it planned now, I am wet venting the sink and toilet together, and the shower will be dry vented. If this is correct, should the dry vent for the shower be located between the shower drain and exit piping (as shown) or should the shower be vented before the shower drain (from the wall to the drain, in a straight line)? Thank you for any help!