Mutliple touches sometimes not working

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Mutliple touches sometimes not working

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Started 2 years ago by Acceleroto
Latest reply from Acceleroto

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Acceleroto
Member

I'm chasing down the last few things before I submit a game to Apple. This one has me stumped.

My game uses multiple touches for control & shooting. Every now & then the game will only register one touch. Shutting down the program & restarting it fixes the problem.

I just looked at the ChipmunkAccel demo and I'm doing everything it does in all the same places to configure the game for multiple touch. My game is a bit bigger than ChipmunkAccel though. I set everything up in the applicationDidFinishLaunching method. The game itself is another scene/layer that gets launched from the main menu.

Has anyone else seen this? Or...is there something I should set in my game layer to make sure multiple touch is enabled?

FWIW, I tried putting this:
[[[Director sharedDirector] openGLView] setMultipleTouchEnabled:YES];
in the init method of my game layer, but it didn't seem to clear things up. I'm testing now with that line in the onEnter method of my game layer.

The odd thing is that everything works great about 99% of the time. I really don't want to ship the game with this problem though.

Any ideas?

Thanks!
-Bryan

Posted 2 years ago #
coolman
Member

Hi,

How are you doing the touching control (ccTouchesBegan)?

With a

for (UITouch *touch in touches) ?

Posted 2 years ago #
Acceleroto
Member
ccTouchesBegan with:
```
for (UITouch *touch in touches) {
```
and ccTouchesMoved, ccTouchesEnded & ccTouchesCancelled with:
```
NSSet *allTouches = [event allTouches];  // <--this gets all the current touches
	for (UITouch *touch in allTouches) {
```
I'm using allTouches because I need to track all touches all the time to make sure I'm controlling the right thing with the right touch.
Posted 2 years ago #
Acceleroto
Member
Well, fudge. I thought the extra
```
[[[Director sharedDirector] openGLView] setMultipleTouchEnabled:YES];
```
in the onEnter method did the trick. However, after about 50 times launching my game, I got multi-touch to fail again.

Has anyone else seen this - or does anyone have any ideas what might be causing this?

Pulling my hair out...

Thanks,
-Bryan
Posted 2 years ago #
coolman
Member

I remember to read anywhere that by desing you don't have guarantee that all touches are processed.

?ll try to remember where I found this.

Posted 2 years ago #
Steve Oldmeadow
Administrator

What device and firmware is this happening on?

Posted 2 years ago #
Acceleroto
Member

I understand that the device might not report all touches all the time, but it's actually only processing 1 touch total on some of my launches. Seems not right.

It's happened on:
iPhone 3G w/2.2.1
iPod touch 2nd gen w/3.0GM (developer's seed)
iPod touch 2nd gen w/2.2.1

Any ideas?

Thanks!

Posted 2 years ago #
coolman
Member
Acceleroto,

And if you change this code
```
NSSet *allTouches = [event allTouches];  // <--this gets all the current touches
	for (UITouch *touch in allTouches) {
```
By

for (UITouch *touch in touches) {

Doesn't solve anything
Posted 2 years ago #
BMR
Member

Hi,
I dont know if I am suggesting you the right solution or not.
Let me tell you the in ccTouchesBegan you will get multiple touch IF AND ONLY IF your fingures will touch the screen at the same time, which will rarely happen.

So to detect double touch you have to use ccTouchesMoved. In this you can detect it because if you move multiple touch it will give you proper data.

Posted 2 years ago #
danielvmacedo
Member

I think that iphone do not give you all the touches all the time... but it treats a unique touch as a single object... so each touch in ccTouchesMoved, ccTouchesEnded & ccTouchesCancelled are the same object.

If you need all the touches all the time, I think you could add them to a collection like MutableArray, but verifying if the touch(object) doesnt exists yet. Did you get what I mean?

Posted 2 years ago #
Acceleroto
Member

In touchesBegan you only get new touches & that's all I'm looking for. So, in my ccTouchesBegan method, I use touch in touches. That's actually the part that isn't working (sometimes).

Posted 2 years ago #
Codemattic
Moderator

Acceleroto, maybe you could make a small project which just shows the problem you are having and we could test it on our devices and look at the code.

Posted 2 years ago #
Acceleroto
Member

Will do. It'll be later today before I get it done.

Thanks!
-Bryan

Posted 2 years ago #
Acceleroto
Member

I made a simple test app & I'm trying to make it reproduce the problem now.

One mistake I noticed in my game is I had <UIApplicationDelegate> set in two classes (the actual app delegate and the class that runs the actual game. Could my intermittent multi-touch problem be caused by that? (feeling stupid)

Thanks,
-Bryan

Posted 2 years ago #
Codemattic
Moderator

It doesnt sound like that could be the problem. You can make multiple objects conform to the <UIApplicationDelegate> protocol - but you can only make one object the app delegate at a time. I dont see how that could be it.

Posted 2 years ago #
Acceleroto
Member

Ok, thanks. I'm messing around with my test app now. The bad part is, it took several hours of playing my game to see the problem. Multiple testers saw it though, so it needs to get fixed. *sigh*

Back to it...

Posted 2 years ago #
Codemattic
Moderator

At first it sounded like problems I hear about OS 3.0 possibly having - but you posted that it also occurred on 2.2.1 devices. Since nobody else is reporting this, I gotta think its a bug specific to your code, so once we see more of it maybe something will stand out. You may just need a new set of eyes on the thing.

Posted 2 years ago #
Acceleroto
Member

Yeah, that's my guess too...it just seems weird that it works 99% of the time. That 1% is killing me!

Posted 2 years ago #
Acceleroto
Member

...of course, now I can't make either my game or my test app have the problem.

If nothing else, I made a nice starting point app for 0.7.3. :)

I definitely need a new set of eyes!

Posted 2 years ago #
coolman
Member

So .. problem solved?

Posted 2 years ago #
Acceleroto
Member

Well, I didn't change anything in my game, so I don't think so. It's just an extremely intermittent problem. I'll keep looking (I've launched both apps about 100 times now with no problems).

Posted 2 years ago #
Codemattic
Moderator

Ever read "The Bug" by Ellen Ullman? Its about a programmer trying to track down a bug which only *intermittently* shows itself. Every time he thinks he's fixed it, it shows up again later.

http://www.amazon.com/Bug-Ellen-Ullman/dp/1400032350

Posted 2 years ago #
Acceleroto
Member

:) I haven't read it, but that's exactly how I feel.

Posted 2 years ago #
coolman
Member

I also suffered this doing a bad add & remove object.

Posted 2 years ago #
Acceleroto
Member

Well, after a couple weeks of chasing it (and thanks to a fellow dev), I can now reproduce my multi-touch bug. I use a UIWebView to display my online high scores. When a user switches to the layer containing the web view, then tries to play, multitouch stops working.

I'll chase it down in the morning & let everyone know what I find...

Of course, I couldn't find this before my game hit the store. *sigh*

Thanks,
-Bryan

Posted 2 years ago #
coolman
Member

Hecks! Wierd thing.

Let us know how finally you solved.

Posted 2 years ago #
Acceleroto
Member

Wow...just figured it out. When I exited my web view later, I didn't removeFromSuperview the UIView that the UIWebView was attached to. That blocked my ccTouchesBegan from seeing more than 1 touch at a time.

I'm cleaning up my test program a little bit now & will share the code for all to use. If nothing else, it shows an example of how to make a UIWebView work in a Cocos2D layer (that took me way too long to figure out).

Feels GREAT to have that bug fixed. I wonder how long Apple will take to approve the update to my game. :)

Posted 2 years ago #
coolman
Member

Oh my! that errors suck!

Nice you solved and thanks in advance for the code you will test.

Posted 2 years ago #
Acceleroto
Member

I built a simple test project to hunt for a multi-touch problem in my game Occurro. After weeks of hunting for a solution, I discovered that I didn't remove a UIView from one of my Cocos2D layers. That caused my ccTouchesBegan method in my game to not work properly.

Here's the test app I built with everything working correctly: http://acceleroto.com/share/MultiTest.zip

The app ("MultiTest") launches to a simple menu where you can select "Play" or "Web View." If you select Play, there are three smiley faces that you can move around with touches or the accelerometer. If you select Web View, it launches the layer containing the UIWebView and automatically takes you to google.com. The web view layer contains a toolbar and button that takes you back to the main menu. Each little part of the web view layer took lots of trial & error and some help from this forum. Hopefully it'll help someone else.

The zip file contains a copy of Cocos2D iPhone 0.7.3. To compile on your own device, make sure you change the provisioning profile and Bundle Identifier to your own. I used the final iPhone 3.0 SDK to compile this for a 2.2.1 target. I did not test it for targeting 3.0.

Feel free to use any of this code for anything you'd like. If you use the layer that displays the UIWebView, keep in mind that Apple wants you to perform checks of the network status and display warnings to the user if there are network problems. My example code does not include the reachability checks.

Thanks for all the help everyone. I hope this code can help someone.

-Bryan

Posted 2 years ago #
Osiris
Member

Provisioning profile? Bundle Identifier? Forgive me, but i'm very noob. What do these mean?

Posted 2 years ago #

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