My suspicion is that you are thinking of the tool VisIt ( https://wci.llnl.gov/simulation/computer-codes/visit/ https://wci.llnl.gov/simulation/computer-codes/v

My suspicion is that you are thinking of the tool VisIt ( https://wci.llnl.gov/simulation/computer-codes/visit/ https://wci.llnl.gov/simulation/computer-codes/visit/ ). VisIt vs yt has some tradeoffs, but by and large it is very useful for rapidly visualizing numerical simulations and supports a large variety of them. I use it daily.