Game's framerate + Simulator questions

Discussion in 'Public Game Developers Forum' started by gammabeam, Nov 8, 2010.

  1. gammabeam

    gammabeam Well-Known Member

    Hi guys!

    This is our first time developing for the iOS platform and we have a few questions regarding the performance of the iPhone/iPod devices.

    So far we wasn't able to test the game on a device (we'll be able to do it next week), that's why some of these questions may look too noobish! :eek:

    1- What's the standard framerate for games on the platform?
    We are focusing on 60 FPS for our game, however things are a bit unstable on the simulator. If we decrease it to 30 FPS, do you think our game will lose some of its appeal?
    I do think running a game on 60 FPS is a good thing, but I dunno, how did this turn out on your games? Also, it is a 2D game, not 3D, so I really think we can be able to keep it over 60 fps!

    2- Is the Simulator slower than the device?
    I really wanted to know it now - I know it could wait for 10-12 days, but we reached a part in the project that it would be nice to know.
    So, is it? :p

    Thanks a lot for your time!
  2. Golden Hammer

    Golden Hammer Well-Known Member

    Dec 1, 2009
    Indie Game Developer
    1) 30 vs 60 fps
    You might be able to pull off 60fps. It depends on your game quite a lot. Chances are 30fps will be a better target. The fill rate is pretty terrible, so if you have a lot of overdraw it will slow you down.

    2) Simulator vs device
    They don't match up at all. The mac GPU and CPU are on a whole different level than the iPhone. Also unless they fixed it recently the simulator is going to be really slow at drawing pvr4 textures because it defaults to software decompression. You really can't use the simulator to judge how the game will run on the device.
  3. Stroffolino

    Stroffolino Well-Known Member
    Patreon Silver

    Apr 28, 2009
    Software Engineer
    The simulator is a terrible predictor for performance on a device. Some things it runs much faster, some things much slower. Other problems you may run into: Filenames are case sensitive on device, but not simulator. Simulator gives you more memory than a device.

    60fps is a tough target to hit. It really depends on how much you're drawing each frame.

  4. Moonjump

    Moonjump Well-Known Member

    May 17, 2010
    Game designer
    Lincoln, UK
    I've got a game in review at the moment (TiltStorm) that runs at 60fps on all the devices I have tested it on, the oldest being an iPhone 3G. I have a fast moving starfield as a background that looks great, but appeared jerky if played at 30fps, so I went for 60fps rather than extra effects (I have more stars on recent devices).

    It is a balance. How much better is the game for running at 60fps verses how many other features could you include at 30?
  5. mr.Ugly

    mr.Ugly Well-Known Member

    Dec 1, 2009
    Berlin, Germany
    first the most important thing.. do NOT use the simulator.. its shovelware.

    always do your testing on a device

    and as stated the fillrate is not good on the powervr chip so having alot of big transparent entities on screen will kill your performance (on older devices) even if its 2d, that doesnt matter as there is no "2d" on the iphone.. everything are hardware accelerated opengl views.. its just a 2d projection.
    so if you have alot of overlapping sprites you can say goodbye to the performance. try o keep such things as small as possible.
  6. Ovogame

    Ovogame Well-Known Member

    Sep 25, 2010
    Game Developer
    Morestel, France
    I'm new to IOS dev but with few months experience...

    First, I'll repeat what the others are saying: the simulator is kind of rubbish and doesn't match at all the device. What are you waitting for to get a proper device :)

    I'm a long time PC dev and it was hard to move to XCODE... So, I made a cross platform libs. I'm creating my games on the PC (and mac too, but I prefer the PC). So, I never use the simulator... in fact my PC version replace the simulator. When I'm happy of the code, I do test it properly on the device and tweak stuff. I spend a lot of time testing on the device, but never developping (except the few objective C stuff I can't do on PC: like IAds/In app purchase...).

    Now, I've dumped the simulator. I haven't touch it for a while and will never go back :)
  7. gammabeam

    gammabeam Well-Known Member

    Hey guys, thanks a lot for the replies!!

    heh, so far we didn't test it on a device because I had some delays starting my company, and couldn't deliver the documents to become a developer... :(
    But this is about to change!

    We do have some parallaxes as backgrounds for our levels, and they are our main concern on the performance issue. But it's nice to hear that the simulator is rubbish, I'm not that worried now :p

  8. Ovogame

    Ovogame Well-Known Member

    Sep 25, 2010
    Game Developer
    Morestel, France
    > We do have some parallaxes as backgrounds

    Be carefull about the fillrate: it's pretty bad on the idevices...

  9. Well, I wouldn't say the simulator is rubbish. It is very useful for testing during the development stage and it usually compiles and executes faster than on the device, which can save time. It doesn't replace testing on the device, however. Things like frame rates can be radically different.

    Both the simulator and the device are useful tools for development.

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