F18 Interceptor: Building my favorite old Amiga game

[Mathias_Westerdahl]

I would say it’s definitely the fact that you are doing calculations so far away from the origin.
I have a list of “smallest steps” that can be represented here:

Floating point precision

Every now and then, you’ll see issues that can be described as “choppy” animations, or perhaps your code doesn’t work when comparing various variables. Sometimes, it could be related to something called “floating point precision”. It stems from the fact that on a computer, real numbers have to be approximated in some way. And as you might imagine, the approximation result might not always be what you intended. (See table at the end) TL;DR: Floating point values… … does not have infinite ra…

At 32km, the difference between each step is ~2cm!
And that will only compound as, of course, there are calculations made with these numbers.

f: 30000  next: 30000.001953125  diff: 0.00195312

Uggh. Life was so much easier when you could just write pixels yourself.

If we’re talking old school rendering, it is very likely that you would have the same problem with overflowing the fixed point math, so the case would still need to be handled.

The suggestion is to move the sensitive calculations back to origin.
E.g. for each sensitive object, translate them back close to origin, and place the camera accordingly and render.
In this case, it may perhaps suffice with moving the airplane back to origin.

I hope this helps!