Creating a new table with auto-generated Time against expression

[Anonymous]

Hi, 

So I have data like this: 

User	Logon Time	Logoff Time
Person A	03/04/2020 10:00	03/04/2020 12:00
Person B	03/04/2020 9:00	03/04/2020 11:00
Person B	03/04/2020 11:00	03/04/2020 13:00

(etc)

My end goal is to have a graph with time on the X axis and count of people logged in on the Y axis. 

A person is logged in if X is greater than Logon Time but less than Logoff time. 

It feels incredibly doable and I feel like my first step needs to be to make a new table. 

I feel like the table's first column should autofill all date/times every 30 minutes from the First logon to the last logoff (or we could use parameters if that's easier?) and then the second column should count each row where Logon < X < Logoff.

Is there any way to autofill a new table with these values and then do the counting in DAX? Even a point in the right direction would be much appreciated. 

[Greg_Deckler]

https://community.powerbi.com/t5/Quick-Measures-Gallery/Open-Tickets/td-p/409364