What I mean is how movement of objects is handled in the game. There are many pitfalls which newer(and I’m not suggesting anyone in this thread is new) programmers may make related to positioning and movement. It’d be equally unhelpful if we lead a newer programmer into thinking Monogame is at fault when there might be deeper issues in their own code.
For instance, if fixed timestep is on, and someone ties all their movement to a fixed value per frame… this works fine, unless frames get dropped, resulting in slowdown/jitters. Or indeed, speed-up, if there were somehow extra frames.
Updating all translation/position data based on the GameTime’s delta time then makes sense.
But even there, there could be issues. The obvious being, that someone uses delta time incorrectly, or makes a mistake in their maths somewhere. Even something as simple as missing a (Cast) to/from a float could cause unintended behavior in the way objects are moved around frame-to-frame. I’d say most of the problems I’ve read about on this issue, related to stuttering/jitters, ended up being some kind of error in the handling of Delta time, or in the maths for calculating movement. All those sorts of things can cause janky looking movements even if the game is running at a very high frame rate.
It’s also possible to get janky movements depending on how the actual rendering is being done. If the game is being tied to a virtual resolution for instance, and that resolution might be low to get a pixelated effect… but depending on how resolution and scaling are being handled, can also cause weird effects in the way things get rendered… or even the way sub-pixel movements may be handled.
Point being, ‘jittery framerate’ is such a nebulous and encompassing problem which covers a massive range of potential causes, it’s good to make sure people consider all the possibilities. Hence my first comment of ‘this is an unsatisfying resolution’, because really, we still don’t know what happened or why it happened. And more to the point, someone visiting this page from Google search months from now might have a totally unrelated issue to yours, but with similar symptoms, and they could walk away from this thread convinced the problem is caused by X or Y even if it isn’t.