How can I make a random CGPointMake, say i created an outlet of a uiimage and called it image, image.center = CGPointMake (//random, //random) everytime second (NSTimer)
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I'd use arc4random() in stdlib.h. This utilizes a much more superior algorithm than rand(). Look up this function in the man pages. You will then want to mod the generated values by the maximum coordinates that you want for both axes.
int x = arc4random() % (int) self.view.frame.size.width;
int y = arc4random() % (int) self.view.frame.size.height;
image.center = CGPointMake(x, y);
csano
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i am getting an error saying something about not allowing frame in QTWO – user840797 Jul 12 '11 at 15:56
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Is this code in your controller? If so, put view between self and frame (self.view.frame). – csano Jul 12 '11 at 16:06
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i have another error saying invalid operands to binary expression (float and CGFloat) – user840797 Jul 12 '11 at 16:13
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Cast the width/height to an int. – csano Jul 12 '11 at 16:28
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How can i do that, what does CAST mean? – user840797 Jul 12 '11 at 18:08
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you can use rand() in stdlib.h
something like:
#include <stdlib.h>
#include <time.h>
srand ( time(NULL) );
int max = 400 // or whatever
int myRandomNumber1 = rand() % max
int myRandomNumber2 = rand() % max
image.center = CGPointMake(myRandomNumber1, myRandomNumber2);
meggar
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if i use this code the image moves far and then SO CLOSE to the place it was before for some reason – user840797 Jul 12 '11 at 16:14
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Use arc4random(), you don't even need to seed it.
image.center = CGPointMake(arc4random() % yourView.frame.size.width, arc4random() % yourView.frame.size.height);
Luke
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if i do the view then it says something about assigning float to CGFloat * i dunno – user840797 Jul 12 '11 at 15:59