cocos2d for iPhone

A fast, easy to use, free, and community supported 2D game engine

1. 

   Apolloe
   Member

   Hi,

   I'm trying to create my own tile map game (not using the other tool, TMX one, since I need to generate my maps procedurally, and they have 3 spatial dimensions). I'm using 32x32 tiles, using a pvr.ccz sheet, and sprite frames to create the sprite textures.

   When I have much more than one screen's worth of tiles (and no tiles behind them - I only draw one layer of tiles at a time), I notice a slowdown on the ipad 2. As I increase the size, it goes slower. I have been able to minimise a lot of the fps slowdown by removing off-screen tiles from being children.

   Am I missing something in terms of optimising speed without removing off-screen children? I looked at this tutorial:
   http://www.raywenderlich.com/1163/how-to-make-a-tile-based-game-with-cocos2d
   and seems to me that that program would have off-screen just as many tiles as mine, if not more, yet no slow speed was reported in the comments that I noticed. Is something happening behind the scenes that's not shown there (or something obvious I missed in the code)? I haven't tried running it, so I don't know how smooth it does actually run.

   Needless to say, it would be easier and smoother experience for the user if I didn't need to remove off-screen children :)

   Essentially, I'd like to know if there's a way to manage these things without removing off-screen tiles, and if not what is a sensible way to remove off screen tiles? (I don't like my current solution, since there's a delay in the tiles showing up as the user scrolls around).

   Thanks

   Posted 11 months ago #
2. 

   Verisutha
   Member

   You are going to need to post examples of your code, talking general theories isn't going to help.

   You didn't say how big the map was that you were loading, nor did you specify what else is going on. ie sprites on screens, effects etc. You also don't specify how many tiles you try to put on the screen at one time (is there scaling involved).

   There are many ways to go about doing this, if you are generating your maps procedurally you should just be able to roll tiles, but that depends on how you went about it.

   Posted 11 months ago #
3. 

   Apolloe
   Member

   I am sorry for the lack of details. The questions you pose were, I thought, implied by my message. I said 32x32 tiles, and if it's much larger than the screen (on an ipad 2), then it runs slow. That means around 800 of these tiles (just enough to cover a bit more than the screen), it's fine. Go up to 1500, iirc, and it's dropping noticeably..maybe 30fps or a bit more?

   As for other things going on, there is nothing - just the tiles, and a text menu (using BMF font). I've only started this project recently. No scaling. As for code, there's nothing really to post. Just add the sprites (from spriteframecrache, set position, add as child to layer).

   Posted 11 months ago #
4. 

   ddionnehb
   Member

   How much texture data do you have?

   Posted 11 months ago #
5. 

   skyhawk
   Member

   This is a shortcoming of TMXTiledMap (it draws EVERY tile), people have suggested workarounds, which are clunky and ugly.

   I hope to upload to cocos-extensions sometime, our implementation (only works for orthogonal maps) which reduces the rendering cost to nearly non-existent.

   The workarounds are generally "split your map up".

   Posted 11 months ago #
6. 

   Verisutha
   Member

   @skyhawk : What cocos files did you modify?

   Posted 11 months ago #
7. 

   skyhawk
   Member

   we branched TMXTiledMap and TMXTiledLayer into our own class which uses many similar functionality, but rewrote some of the core drawing and initialization

   Posted 11 months ago #
8. 

   psykano
   Member

   @skyhawk: I am very interested in that as well.

   Posted 11 months ago #
9. 

   Jim Love
   Member

   On iPad, I've tested maps of various sizes... 50 x 50, 30 x 30, 20 x 20 and I get no performance improvement with smaller maps. So the old "split your map" advice doesn't seem to matter. The slowdown for me occurs when there are more tiles on screen. If I have a long "hallway" with only a band of tiles, my frame rate jumps back up.

   You might say, "What's so strange about that? More tiles on screen, more work to draw = slower frame rate." Well, not so fast. I have a character running around a map with an animating idle pose (breathing and a liquid tank on his back that sloshes) and just for kicks I instantiated several of him all over the screen with no slowdown...that's a dozen animations all drawing at the same time...no drop in fps. Yet, the fps changes dramatically + or - if I move the character to part of the map that has a dozen more or a dozen less tiles rendering. Each tile seems SO expensive in terms of fps, but blitting animations of a character is not.

   So, I'm begging all you smarter-than-me coders (just about everyone) to optimize the tilemap code in Cocos2D... for the children. For the love of all humanity, think of the children! (or childish adults).

   Posted 11 months ago #
10. 

    skyhawk
    Member

    http://www.cocos2d-iphone.org/forum/topic/17945

    Posted 11 months ago #

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