Should TileMapAtlas degrade performance this much?

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Should TileMapAtlas degrade performance this much?

(14 posts) (5 voices)

Started 2 years ago by OJDee
Latest reply from patrickC

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OJDee
Member

Hi

I've taken the code from the AtlasTest demo, specifically the tilemapatlas code, and integrated it into my project, simply loading and displaying the map as per the demo.

[Texture2D saveTexParameters];
[Texture2D setAliasTexParameters];

map = [TileMapAtlas tileMapAtlasWithTileFile:@"tiles.png" mapFile:@"levelmap.tga" tileWidth:16 tileHeight:16];

[Texture2D restoreTexParameters];
[map releaseMap];

[self addChild:map z:0 tag:kTagTileMap];

I have a schedule calling

[map setPosition:ccp(-player.x, -player.y)];

This works fine in the simulator, holding around 60fps.

When I put this in the device it never rises above 20fps. I have now taken out the schedule and don't interact with the map at all once initialised - it just sits in the background, but my framerate has still gone to pot.

If I remove the initialising code, the framerate returns to 60 again.

Is there a sweet spot in terms of map dimension/tilesize - for example should a map size be in multiples of something.

I've also seen mention of pvrtc and 16bit textures - is this likely to return noticeable gains?

Cheers for any guidance
Oli

Posted 2 years ago #
riq
Key Master

Did you try running the AtlasTest (TileMap example) on your device ? At what speed does it run ?
what device do you have ? iPhone 3g ? iPod Touch 2nd gen?

pvrtc (2-bit or 4-bit) or 16bit textures will give you a performance boost.

Posted 2 years ago #
OJDee
Member

Hi Riq.

I'm on an iPhone 3G.
Sorry, the performance drop comes when I swap out the levelmap.tga with my own which is using the same tiles file. My map file is 100x100, completely filled with 16x16 tiles.

I guess since the levelmap.tga file does not completely fill the screen with tiles, there is less to calculate, but for top down games I will need a tile at every position rather than having an image show through from below.

I have converted the tiles.png to a pvr but performance is still the same.

Is 100x100 unrealistic?

Thanks
Oli

Posted 2 years ago #
patrickC
Member

Hi there, I've been doing a top-down car game that heavily relies on tilemapatlas.
To allow good performance but still have a big "world", I split my map into lots of smaller maps, then depending on the position of the vehicle I hide and show the tilemapatlas(es) in question.
I'm using tiled with a modified version of the .tga export plugin to support divisions into smaller files.
Hope that helps
Patrick

Posted 2 years ago #
OJDee
Member

Hi Patrick,

Thanks for the response - Have you found this to eliminate all performance issues? Are you able to keep 16x16 tiles?

I have tried 32x32 tiles in a 50x50 map and it helps but it seems like your solution should do the trick much better, and hopefully allow me to restore 16x16 tiles for greater detail. Are there any artifacts where two maps touch?

Cheers
Oli

Posted 2 years ago #
patrickC
Member

I'm using 64x64 tiles, started off with 32x32 but need a "pixelated" look and apparently it's a bad idea to scale tilemapatlas (it creates artifacts between tiles), so I just scaled the tiles themselves to 64x64.
I'm using a 128x128 tilemap with 16 divisions (will soon try with a 256x256 with 64 divisions), so every tilemap is 32x32.
I have at most 4 tilemaps showing at any given time, and on an iPod Touch 1st gen (the slowest) I get around 60fps with the occasional drop.
I don't see why you shouldn't be able to use 32x32 tiles, perhaps you'll just need to divide your map into even smaller sections?
About the artifacts, I'm still not 100% sure what causes them, it's a combination of these factors (i think...)
- scaling the tilemapatlas
- moving the camera and changing the z value incrementally (even worse when in landscape mode for some reason)
So, I ditched my "dynamic" camera that zooms out depending on the speed of the vehicle, just keep a Z value that doesn't create artifacts, and also important, since I'm centering the camera on a chipmunk body, I always round up the coordinates to integers when moving the camera, seems that if the camera moves to a float value it can create those artifacts.
Hope that helps, let me know if you're wanting the modified version of the .tga export plugin in case you're using tiled.
cheers
Patrick

Posted 2 years ago #
OJDee
Member

Sounds like we are building similar games, I was also planning on a zoom function based on vehicle speed so you could see further ahead, but it sounds like there are issues with that approach.

I'm curious about the use of Chipmunk for dynamics though, I considered it but wasn't sure how you would specify a different resistance laterally compared to longitudinally as required for a rolling vehicle - how has that worked out for you?

Also, are you able to treat the chipmunk layer as you would any other layer, therefore have the map visible and managed underneath in one layer and a gui on another on top?

It would be great to take a look at that exporter for Tiled, I am now using that editor.

Cheers
Oli

Posted 2 years ago #
patrickC
Member

Yeah I suppose we are building similar games actually.
I decided to ditch the dynamic zooming for now and just stick with an "always far away" camera, when I have more time I'll try and find a solution for the gap between tiles problem.
About using chipmunk for the simulation, I manually calculate lateral friction and torque values to move the car about, there's a rather extensive post I started on the chipmunk forums http://www.slembcke.net/forums/viewtopic.php?f=1&t=463 , it's all discussed in detail, if you have more questions regarding the use of chipmunk for the vehicle just post them there.
Layers are pretty straightforward, I have a sprite for my vehicle (and sprites for ai vehicles too), and at every step I update the position of the sprite based on the position of the simulated body, then yes I have a layer on top for the GUI.
You'll need to download the Tiled source and the tga exporter source (google), and get that to compile, then I can send you the modifications for the plugin so that it exports into a series of smaller tilemaps.
Cheers!
Patrick

Posted 2 years ago #
DogCow
Member

Would you be willing to post that code somewhere public? I too have a need to subdivide a large tilemap into smaller sections for performance reasons.

I've had troubles using the level.tga's exported from tiled... I just end up with a black screen. However I have been able to get level.tga's saved from the pgu tools to work w/ cocos2d-iphone.

Posted 2 years ago #
patrickC
Member

Sure.
Get it here http://cleverhamstergames.com/tgaexporter.html
Let me know if you're having any problems.
For the exported to work just make sure your tileset is named "tiles" and the layer on which you're drawing is named "tile".
This modified version will only chop up the "tile" layer but if you need it do include the other layers it should be quite easy, just copy and paste :)
I was looking for something that would allow me to get a .tga and split it up but couldn't find anything so just decided to modify the .tga exporter, seemed like the quickest solution.
cheers
Patrick

Posted 2 years ago #
DogCow
Member

Patrick,

That's pretty much exactly what I needed. Thank so much for sharing.

I've hacked your hack. Regarding file names, I was getting something like, "level.3tga.tga" when I exported. I changed it to give something like, "level_01,04.tga". Also I've modified it to handle multiple rows & columns of sections (thus the 01,04 being row 1, column 4). If you'd like my changes let me know how I can get them to you (e-mail?).

Posted 2 years ago #
patrickC
Member

Ah, cool.
You could email it to me if you like, if you click on my username it will take you to the website and you can contact me through there.
I got in touch with the original author of the plugin and he was interested in the changes and said he'll integrate them in an update, so I'll pass him your better version.
I got lazy with the file names :)
thanks for sharing back! :)
patrick

Posted 2 years ago #
snoe
Member

Hey guys try out the code posted at http://code.google.com/p/cocos2d-iphone/issues/detail?id=544 I was about to try multiple tile maps but I found this works just as well.

Posted 2 years ago #
patrickC
Member

sweet, thanks!

Posted 2 years ago #

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