Samsyn, For multiplayer synchronization, you absolutely can not count on the current time of either device. Here's one way to handle it:
Both host and client use System.nanoTime() / 1000000; That gives you a fairly accurate counter to use. Host sends snapshots with their current time. Client adapts the host's time for interpolation by attempting to detect ping and use it as a skew. On Mar 10, 7:36 pm, Samsyn <d...@synthetic-reality.com> wrote: > so... I am testing my multiplayer game by running several instances of > the emulator (which is, sadly, extremely slow and dis-satisfying). > > I depend on a little trick using currentTimeMillis() to keep a > synchronized clock between the players (but NOT the absolute value of > currentTimeMillis() since no two phones are probably set exactly the > same) > > Anyway, I *do* naively assume that two emulators, running on the same > PC would return near identical values for calls to > currentTimeMillis(), and what I find is that they start off the same, > but pull rapidly apart. > > Which makes me think the underlying implementation of > currentTimeMillis() in the emulator is not at all based on the host > PC's calendar, and rquires the emulator to get enough Windows compute > cycles to be anything close to accurate. (and one emulator is always > running at a lower priority to the other, depending on which one is on > top) > > If this is just an artifact of the emulator, then I can deal with it, > but if it implies I have a fundamental misunderstanding of > currentTimeMillis(), then that would be something i need to deal with. > > Part two of the question is: any way I can speed up the emulator? > When I run two, are they sharing one of my cores? Can I split them > onto separate cores? -- You received this message because you are subscribed to the Google Groups "Android Developers" group. To post to this group, send email to android-developers@googlegroups.com To unsubscribe from this group, send email to android-developers+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/android-developers?hl=en
