The issue at the link you give makes a pretty good case for using fixed point buffers instead of floating point buffers (at least before Gingerbread), yet you still say "hence working with FloatBuffers".
On Feb 25, 2:04 am, RyanMcNally <[email protected]> wrote: > I've not much to add, but at any rate: > > 1) As has been noted, GC is the enemy. String manipulation, boxing/ > unboxing, using most collections other than ArrayList, > Collections.sort(), Arrays.sort() - they all create garbage and you > simply cannot use them on a per-frame basis. > Happily the GC pauses are so noticeable that you'll quickly turn to > the (excellent) allocation tracking tools to root out the problem. > > 2) Everyone doing OpenGL work, and hence working with FloatBuffers, > should be aware ofhttp://code.google.com/p/android/issues/detail?id=11078 > > Ryan > > On Feb 25, 7:04 am, oldskool73 <[email protected]> wrote: > > > > > > > > > It's good of you put some suggestions out there to help others, and > > I'm not trying to have a dig, but none of those tips have anything to > > do with opengl(es) specifically. If you really want some indepth > > opengles tips and insight you can't go far wrong with reading through > > the posts on the badlogic blog: > > http://www.badlogicgames.com/wordpress/ > > > RE 1- this depends rather on what you are making, I'm currently > > building a fast shooter and have specifically chosen not to do this, > > if a frame takes longer to render I'd prefer the game to slow down and > > still be playable than have the enemies suddenly 'jump' because the > > time elapsed is greater than average, your point 5 may help this > > though I guess. > > > 2 & 3 - agreed, the GC is not your friend (although its a lot better > > in gingerbread than previously), and surprisingly few people seem to > > know about or use some of the cool tools hidden in the ddms view. > > > 4's not really practical when testing real world situations, you can't > > ask your users to switch to airplane mode to use your app. > > > sorry to be so pedantic :) > > > A > > > On Feb 24, 4:21 pm, Tom Cowan <[email protected]> wrote: > > > > I'm sure anybody who's used openGL will of come across a situation > > > where the animation or movement isn't smooth so here are some tips in > > > the hope of people posting some more. > > > > 1. Make sure you animate/move using a timer to maintain a constant > > > rate of movement regardless of processing speed. So, > > > > x = now > > > draw 1st frame > > > y = now > > > movementFactor = y - x; > > > draw 2nd frame > > > repeat > > > > That sorts some problems. > > > > 2. Stop the GC firing. If you're getting the gc firing message in the > > > logcat whilst movement or animation is taking place your likely to be > > > allocating ram. You can check this in ddms, goto the allocation > > > tracker, hit start tracking then get allocation and you'll see what > > > methods have been allocating ram. > > > > 3. Stop allocations even if the GC isn't firing! This helped me a > > > bundle, I was allocating a lot of Strings and once I sorted this out I > > > found the frame rate to fluctuate less. > > > 4. Put the phone in airplane mode when doing performance testing and > > > kill all tasks prior to running your app. > > > > 5. (Not tried this one yet) Apparently you're eye is very good at > > > seeing jerks in animations.movement so it's actually better to reduce > > > your frame rate artificially as explained by Mario Zechner below, > > > > "Average your delta times, it's the only way you can smooth > > > things out. I use a window of 5 frames per second for which i sum up > > > the delta times and divide by the number of frames. > > > > An example, > > > 15ms, 15ms, 33ms, 15ms, 15ms will give you an average delta time of > > > 18.6ms for frame 6. The 33ms will also influence the delta time of the > > > next 4 frames after it. To avoid that effect you could use weighted > > > averaging: frame delta times that are newer receive a higher weight > > > (just an example, haven't boughtered using it)" > > > > Does anyone have any other ideas concerning this topic? -- You received this message because you are subscribed to the Google Groups "Android Developers" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/android-developers?hl=en
