Not a bug
BYOND Version:490
Operating System:Windows 7 Ultimate
Web Browser:Firefox 6.0.1
Applies to:Dream Seeker
Status: Not a bug

This is not a bug. It may be an incorrect use of syntax or a limitation in the software. For further discussion on the matter, please consult the BYOND forums.
Descriptive Problem Summary:
When trying to upgrade my project from tile based movement to pixel movement, It seems to jump from the specified step_size to the next.
Numbered Steps to Reproduce Problem:
1. First try only set step_size to 10
2. Second try set both step size to 10 and FPS to 40
3. Third try, lowered FPS to 20
All of these producted the same results.

Expected Results: Smooth transitions from movement to movement.

Actual Results: Nappy jumps from the defined step_size to the next.

Does the problem occur:
Every time? Or how often? Everytime
In other games? Wasn't jumpy in a new project but animations came out choppy
In other user accounts? Haven't verified but most likely, yes.
On other computers? ^

When does the problem NOT occur? When starting a project from scratch.

Did the problem NOT occur in any earlier versions? If so, what was the last version that worked? Nah

Workarounds: None that I know of.

I don't follow your description at all. Can you clarify what you're seeing here?
I believe that he is referring to the lack of smooth transitions between pixel step spots. Instead of gliding as it does with the default movement settings, it jumps from one point to the other. Although I assume that this is no bug, and is how pixel movement works. If you're step_size is about 4, it seems to be a bit smoother. Try lowering the step_size a bit more, Abdel, see if that doesn't fix the problem.
Pixel movement completely obliterates gliding. If you move an object at a speed of 10px it's assumed you want it there ASAP. Gliding is only used when doing full-tile jumps, and only when the object does not use step_x/y and has bounds that are a multiple of a full tile size.
I notice that if I download your pixelicious demo, and I change the smily's step_size to 32, and FPS to 10, he moves from tile to tile smoothly. But if I take the source to my game, which has been compiled by many, many old versions of BYOND, and has step_size=32 and FPS=10 also, it doesn't move from tile to tile smoothly any more. I realize gliding is gone, but I still see a smooth transition from tile to tile in your pixelicious demo, while the same step_size in my game compiled in 490, leaps 32 pixels instantly.

I think it's the same thing this guy is referring to.
I don't get what you're saying. If you didn't change your source the old game should still run just fine. But if you added bounds or a step_size or any kind of step offsets at all, a step_size of 32 won't produce gliding the instant your mob acquires a step_x/y.
Ok yea I had altered the bounding boxes but not the step_size, I didn't know that changing bounding boxes would disable the gliding.

Thanks for the pixel movement it's quite nice.
The reason the gliding turns off is that when you bump you're achieving a partial movement and it's taking you off the tile grid. As long as the only objects you can bump into are set with bounds along discrete tile edges, you'll never change step_x/y from bumping into them and therefore gliding will still work.
Closing this as it appears to be identical to the other issue reported by the same poster.