🎉 Moby Dick has been slain! 🎉


Almost a year ago I posted this: (click on the down-caret on the right to expand it, if you’re interested in what I wrote at the time)

It was about a flicker that occasionally occurred on the game’s main menu screen, which I declared as “my personal Moby Dick”. Tracking it down has certainly been a bit of an obsession, over the years, but I’ve finally figured it out and solved it!

The thing that made it hard to debug was just that it wasn’t repeatable; when the flicker happened, it would last for just a single frame, and would typically happen only once every ten or twenty minutes of sitting on the main menu and watching for it, although it could also happen several times in just a few seconds (and this is what would usually start me searching for it again). But it happened so infrequently that it was almost impossible to debug in the usual manner, and every time I’ve dug in to try to find and fix the problem, I failed utterly. Until now.

MMORPG Tycoon 1 also had a flicker on its title screen, but that one was put there intentionally. Which didn’t reduce the number of people filing bug reports about it, I’ll note. Message to future-me: do not use “rendering appears to be slightly broken” as a stylistic choice! It causes nothing but bug reports.

Suffice to say, there was a very interesting (to a programmer), low-level bug at the heart of the problem. And I found a workaround several hours before I was able to pinpoint the actual problem. (But I carried on to actually figure out what the problem actually was because I had sort of promised a blog post about it!)

The problem itself? Well… that will go into its own technical blog post. It’s definitely the longest-lived bug I’ve ever found and fixed.

I just really wanted to celebrate that at long last, the beast is finally well and truly dead. :smiley:

Now, back to my TODO list for the MS15 build!