Venting a bathroom

I'm doing a rough in inspection on my new house that sits on a slab. My question is where does the vent go. This is my understanding of how it works. Please give me some help.

waist line
l
l
l
l \ wye to catch a sink
l
l \ wye to catch a shower with shower box
l
l
l \ wye to catch a toilet
l
l Long sweep 90 up and out for vent

vents

You need vents at the shower and sink. The long sweep at the end may, or may not, be suitable for the toilet vent. It depends on your code and the inspector.

Thanks for the quick response can't the vent for the sink and shower tie in to the vent in the wall?

What happens if you are running water in more than one fixture at the same time? Suck drains dry. Each fixture needs its own vent. Now, the vents don't have to individually go through the roof, you can combine them prior to that.

You can join the vents in the wall, yes. But you have to do it a certain distance above the flood rim of the sink; that is, the vent has to take off vertically from the sink/shower drains and rise up a certain dist before turning 90 to join the other vent.

Also, I'm not sure you want to drain everything into your waist line; your pants might get dirty. I'd drain into the waste line