Strange CGRectIntersectsRect problem

[iphonechilly]

Hi,

I've got this strange collision problem.
I rotate my 'ant objects' with this piece of code, where 'absoluteDraaiHoek' is the direction in degrees:

#define DEGREES_TO_RADIANS(__ANGLE__) ((__ANGLE__) / 180.0 * M_PI)
CGAffineTransform cgCTM = CGAffineTransformMakeRotation(DEGREES_TO_RADIANS(absoluteDraaiHoek));
image.transform = cgCTM;

Then in the gameloop I check for collision like this:

if(CGRectIntersectsRect(tmpAnt.image.frame, player.image.frame)){
			tmpAnt.collisionWithPlayer = YES;
		}else{
			tmpAnt.collisionWithPlayer = NO;
		}

When collisionWithPlayer is true, the ant won't move.
But this results in the following situation:



As you can see the ant in the upperleft corner does not intersect with the players rect, but CGRectIntersectsRect returns true!
I suspect something is happening like the following screenshot:



Now my question is, when rotating an UIImageView, does the original frame rotate too? Or does its frame change like the second screenshot?
If so, how to handle that correctly?

Thanks in advance.

[iphonechilly]

Just like I expected the frame of the UIImage changes when rotated:

2010-02-18 19:42:20.530 Ants[2982:207] FrameWidth: 61.072174, FrameHeight: 62.450989
2010-02-18 19:42:20.570 Ants[2982:207] FrameWidth: 44.031250, FrameHeight: 51.303574

Does anyone have a workaround for this?

Cheers

Edit:
I'm using smashers sollution to calculate the distance between the two center points (instead of origins):
http://www.iphonedevsdk.com/forum/50296-post2.html

for(Ant *tmpAnt in arryAnts) {
               [tmpAnt doMove];

               dx=tmpAnt.image.center.x - player.image.center.x;
               dy=tmpAnt.image.center.y - player.image.center.y;
               distance = sqrt( (dx*dx) + (dy*dy) );
               if(distance<=20){
                       tmpAnt.collisionWithPlayer = YES;
               }else{
                       tmpAnt.collisionWithPlayer = NO;
               }
       };

This works out fine for me now. I should play a little with the distance value though:


So I owe a big thanx to smasher!

[iphonechilly]

I'm using smashers sollution to calculate the distance between the two center points (instead of origins):
http://www.iphonedevsdk.com/forum/50296-post2.html

for(Ant *tmpAnt in arryAnts) {  
		[tmpAnt doMove]; 
		
		dx=tmpAnt.image.center.x - player.image.center.x;
		dy=tmpAnt.image.center.y - player.image.center.y;
		distance = sqrt( (dx*dx) + (dy*dy) );
		if(distance<=20){
			tmpAnt.collisionWithPlayer = YES;
		}else{
			tmpAnt.collisionWithPlayer = NO;
		}
	};

This works out fine for me now. I should play a little with the distance value though:


So I owe a big thanx to smasher!