float value changes when passed to function

float value changes when passed to function - Printable Version

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float value changes when passed to function - kendric - Nov 14, 2009 08:51 PM

I am using cocos2d. While debugging an issue I discovered it was caused by the following:

cocos2d code:
check elapsed time for the tick event. If > whatever call my selector and pass time
Time is stored as a cctime which is typedef from a float

In my selector i also accept a cctime.

When I am stepping through the cocos code I see an expected value for time. When it calls my selector I see a value for time like 0.31231323x10^30

Anyone know why a selector with the same variable type might do this?

float value changes when passed to function - kendric - Nov 14, 2009 08:56 PM

Further investigation shows even stranger stuff going on here...

Code:

-(void) step: (ccTime) delta

{

    printf("Delta before %f\n",delta);

    delta=0.001f;

    printf("Delta after %f\n",delta);

    levelPassTime(level,delta);

First it won't even stop at a breakpoint on the delta= line
2nd if i stop at the levelPass line and inspect delta its value is various things but nothing anywhere close to what I just set it to... The print outs show:

Delta before 0.000000
Delta after 0.001000

Something funky this way comes...

float value changes when passed to function - cmiller - Nov 14, 2009 10:50 PM

kendric Wrote:Further investigation shows even stranger stuff going on here...

Code:

-(void) step: (ccTime) delta { printf("Delta before %f\n",delta); delta=0.001f; printf("Delta after %f\n",delta); levelPassTime(level,delta);

First it won't even stop at a breakpoint on the delta= line
2nd if i stop at the levelPass line and inspect delta its value is various things but nothing anywhere close to what I just set it to... The print outs show:

Delta before 0.000000
Delta after 0.001000

Something funky this way comes...

Not quite. Something funky this way came.

http://www.cocos2d-iphone.org/forum/topic/2426

Try casting it to a float; perhaps you'll solve the problem?

float value changes when passed to function - kendric - Nov 15, 2009 09:14 AM

I think its due to some sort of assembled code and what I see being out of sync. WHen I run the same thing with it on the device instead of simulator its fine.

float value changes when passed to function - OneSadCookie - Nov 15, 2009 12:48 PM

I suspect it's due to you calling a function or method without a prototype. That'll happen to work on the device, and not on the simulator.

Use the warning settings from this page: http://www.idevgames.com/irc and fix the resulting errors.

float value changes when passed to function - kendric - Nov 15, 2009 01:57 PM

I figured this out. I had it set to release mode and I wasn't debugging the code I thought I was because I guess for release mode it compiles things into more efficient blocks.