Hi all. I wrote this speedrunning companion script for SMB1 running on FCEUX.

https://raw.githubusercontent.com/Hubcapp/smb1-timer-splits-xpos/master/smb1_timer_splits_xpos.lua

Let me know if there are any bugs.

If you're using Windows, these keyboard toggles may or may not work. If you're on Linux or macOS they WON'T work (as of FCEUX release 2.2.3, there is no keyboard input accessible via lua):

¤ Press ] to toggle showing the offset between your current run time and your PB run time (in framerules)

¤ Press F4 to toggle a framerule counter at the bottom left of the screen

¤ Press F6 to toggle displaying splits, PB offsets, and time spent on the last level

¤ Press F8 to toggle displaying how many pixels Mario is from the left side of the screen on World 4-2

¤ Press F9 to toggle displaying your total framerule offset (useful if you are consistent enough to know how to react to enemies depending on what framerule you're on)

On Linux and macOS, you may edit the source code to toggle these variables. They're all up at the top with comments.