Hello, once again, since I had no reaction at all to my previous post:
I have jittering issue aswell, but related to the platform behavior. PLEASE TAKE A LOOK, IT MIGHT BE RELATED, possibly providing some hints to the cause of the jittering/jerking-problem.
I have experienced this since I use Construct 168, and it has been always there. (Eventually, I manage to get a smoother platform movement, but I don't know exactly how... also never 100% smooth, which is annoying.) In this example case, it is just a plain platform behavior inserted, and pixel rounding turned on. (Please note: the cam-scroll is not important, it also happens to the platform object, when the cam is not following it.)
http://www.exitthegame.eu/test
I have tested it on different PCs and Macs, all with the same jittering result, in Chrome, IE (11), FF, Safari. This also happens, when exported via Web-Nod.
Oddly, sometimes the shaking/jittering is horizontal, sometimes vertical, but always there.
Do you experience a shake there? If not, here is a video of what I mean: https://dl.dropboxusercontent.com/u/297 ... truct2.rar
Also the file test.capx is attached below.
One more thing to add: when I add PlatformSprite > Set position to (round(self.X, self.Y), the platform object is always snapping one pixel down and right, when I press any platform controlling buttons. When I release them, the platform snaps back 1 px to -x and -y. You would expect it not to do that at all, since rounding of X should not be influenced by moving only Vertically and so on. See test-rounding.capx This is important, since the same effect might cause the Platform shaking in the other example, since pixel rounding is on (meaning that the displayed sprite is at a rounded position, whereas in my example I also round the object itself to a rounded position, which seems to soften the shaking, but still not working properly, as described.)
Since the effect seems to be very similar, I think it could be very related...