Enemy not moving in the right direction...

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Enemy not moving in the right direction...

(31 posts) (4 voices)

Started 9 months ago by irvaz
Latest reply from Gray Olson

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irvaz
Member

Hi Im trying to get an enemy to move from top to bottom, I am in landscape mode.

I have been studying this code and have modified it to move on the X axis. Unfortunately the enemy moves from top to bottom but diagonally as if its being dragged to the y axis. Would really appreciate if anyone has an idea what the problem is?

Thanks

-(void)addTarget {

  CCSprite *target = [CCSprite spriteWithFile:@"Target.png"
    rect:CGRectMake(0, 0, 27, 40)]; 

  // Determine where to spawn the target along the Y axis
  CGSize winSize = [[CCDirector sharedDirector] winSize];
  int minY = target.contentSize.height/2;
  int maxY = winSize.height - target.contentSize.height/2;
  int rangeY = maxY - minY;
  int actualY = (arc4random() % rangeY) + minY;

  // Create the target slightly off-screen along the right edge,
  // and along a random position along the Y axis as calculated above
  target.position = ccp(winSize.width + (target.contentSize.width/2), actualY);
  [self addChild:target];

  // Determine speed of the target
  int minDuration = 2.0;
  int maxDuration = 4.0;
  int rangeDuration = maxDuration - minDuration;
  int actualDuration = (arc4random() % rangeDuration) + minDuration;

  // Create the actions
  id actionMove = [CCMoveTo actionWithDuration:actualDuration
    position:ccp(-target.contentSize.width/2, actualY)];
  id actionMoveDone = [CCCallFuncN actionWithTarget:self
    selector:@selector(spriteMoveFinished:)];
  [target runAction:[CCSequence actions:actionMove, actionMoveDone, nil]];

}

my code looks like this -

CGSize winSize = [[CCDirector sharedDirector] winSize];
	int minX = enemy.contentSize.width/2;
	int maxX = winSize.width - enemy.contentSize.width/2;
	int rangeX = maxX - minX;
	int actualX = (arc4random() % rangeX) + minX;

	enemy.position = ccp(actualX, winSize.height + (enemy.contentSize.height/2));
	[self addChild:enemy];	

	int minDuration = 2.0;
	int maxDuration = 4.0;
	int rangeDuration = maxDuration - minDuration;
	int actualDuration = (arc4random() % rangeDuration) + minDuration;

	id actionMove = [CCMoveTo actionWithDuration:actualDuration
										position:ccp(-enemy.contentSize.height/2, actualX)];
	id actionMoveDone = [CCCallFuncN actionWithTarget:self
											 selector:@selector(spriteMoveFinished:)];
	[enemy runAction:[CCSequence actions:actionMove, actionMoveDone, nil]];

Posted 9 months ago #

Gray Olson
Member

Your problem is actionMove this is how it would look like if it was correct:
id actionMove = [CCMoveBy actionWithDuration:actualDuration position:ccp(0, winSize.width)];

Posted 9 months ago #
irvaz
Member

Hi thanks for the reply i tried the above but now I get nothing, no enemies on the screen...

Posted 9 months ago #
Gray Olson
Member

Thats the fault of the positioning code, your putting it off the screen above at a random x position. You want it to be off screen to the right and at a random y position. See if you can figure out how to do that on your own.

Posted 9 months ago #
irvaz
Member

Hi I hope I am reading this write (extremely new to cocos2d and coding)

This line will start the enemies position, screens height + half the enemies height?

enemy.position = ccp(actualX, winSize.height + (enemy.contentSize.height/2));

And this line will be where the enemy ends up, iimf honest im a little unsure how to read ' -enemy.contentSize.height/2, actualX'

id actionMove = [CCMoveTo actionWithDuration:actualDuration position:ccp(-enemy.contentSize.height/2, actualX)];

Thanks for your replys

Posted 9 months ago #
phil_me_up
Member

Basic rule is that when setting the position you do it with ccp(x,y).

In your first line of code you're right, it sets the x position to whatever 'actualX' is and the y Position to the height of the screen, plus half the height of the sprite. Depending on where you're anchor point is, this will put it somewhere at the top or above the screen.

Your second line of code defines where the sprite will move to (hence the CCMoveTo). In this case you seem to have set the x and y the wrong way round (i.e. ccp(y,x) rather than ccp(x,y)) which would of course mean your sprite never ends up where you want it to - try swapping things around if that helps. Note that the enemy.contentSize.height/2 will probably put the y position somewhere at the bottom of the screen.

Posted 9 months ago #

irvaz
Member

YES!!! THATS IT THANK YOU VERY MUCH!!!

CGSize winSize = [[CCDirector sharedDirector] winSize];
	int minX = enemy.contentSize.width/2;
	int maxX = winSize.width - enemy.contentSize.width/2;
	int rangeX = maxX - minX;
	int actualX = (arc4random() % rangeX) + minX;

	enemy.position = ccp(actualX, winSize.height + (enemy.contentSize.height/2));
	[self addChild:enemy];	

	int minDuration = 2.0;
	int maxDuration = 4.0;
	int rangeDuration = maxDuration - minDuration;
	int actualDuration = (arc4random() % rangeDuration) + minDuration;

	id actionMove = [CCMoveTo actionWithDuration:actualDuration position:ccp(actualX, (-enemy.contentSize.height/2))];

	id actionMoveDone = [CCCallFuncN actionWithTarget:self
											 selector:@selector(spriteMoveFinished:)];
	[enemy runAction:[CCSequence actions:actionMove, actionMoveDone, nil]];

Posted 9 months ago #

irvaz
Member

Not sure if I should be asking this here or starting a new topic but here gos..

ive been following ray wenderlichs simple game tutorial, ive worked on the enemies im now having some trouble with the projectiles.

I've changed the player and enemy so they now move from top to bottom, i now want to change the projectiles

this is the code ive followed

- (void)ccTouchesEnded:(NSSet *)touches withEvent:(UIEvent *)event {

  // Choose one of the touches to work with
  UITouch *touch = [touches anyObject];
  CGPoint location = [touch locationInView:[touch view]];
  location = [[CCDirector sharedDirector] convertToGL:location];

  // Set up initial location of projectile
  CGSize winSize = [[CCDirector sharedDirector] winSize];
  CCSprite *projectile = [CCSprite spriteWithFile:@"Projectile.png"
    rect:CGRectMake(0, 0, 20, 20)];
  projectile.position = ccp(20, winSize.height/2);

  // Determine offset of location to projectile
  int offX = location.x - projectile.position.x;
  int offY = location.y - projectile.position.y;

  // Bail out if we are shooting down or backwards
  if (offX <= 0) return;

  // Ok to add now - we've double checked position
  [self addChild:projectile];

  // Determine where we wish to shoot the projectile to
  int realX = winSize.width + (projectile.contentSize.width/2);
  float ratio = (float) offY / (float) offX;
  int realY = (realX * ratio) + projectile.position.y;
  CGPoint realDest = ccp(realX, realY);

  // Determine the length of how far we're shooting
  int offRealX = realX - projectile.position.x;
  int offRealY = realY - projectile.position.y;
  float length = sqrtf((offRealX*offRealX)+(offRealY*offRealY));
  float velocity = 480/1; // 480pixels/1sec
  float realMoveDuration = length/velocity;

  // Move projectile to actual endpoint
  [projectile runAction:[CCSequence actions:
    [CCMoveTo actionWithDuration:realMoveDuration position:realDest],
    [CCCallFuncN actionWithTarget:self selector:@selector(spriteMoveFinished:)],
    nil]];

}

and

self.isTouchEnabled = YES;

i have changed it to this

- (void)ccTouchesEnded:(NSSet *)touches withEvent:(UIEvent *)event {

	// Choose one of the touches to work with
	UITouch *touch = [touches anyObject];
	CGPoint location = [touch locationInView:[touch view]];
	location = [[CCDirector sharedDirector] convertToGL:location];

	// Set up initial location of projectile
	CGSize winSize = [[CCDirector sharedDirector] winSize];
	CCSprite *projectile = [CCSprite spriteWithFile:@" "
											   rect:CGRectMake(0, 0, 0, 0)];
	projectile.position = ccp(20, winSize.width/2);

	// Determine offset of location to projectile
	int offX = location.x - projectile.position.x;
	int offY = location.y - projectile.position.y;

	// Bail out if we are shooting down or backwards
	if (offX <= 0) return;

	// Ok to add now - we've double checked position
	[self addChild:projectile];

	// Determine where we wish to shoot the projectile to
	int realX = winSize.height + (projectile.contentSize.height/2);
	float ratio = (float) offY / (float) offX;
	int realY = (realX * ratio) + projectile.position.y;
	CGPoint realDest = ccp(realX, realY);

	// Determine the length of how far we're shooting
	int offRealX = realX - projectile.position.x;
	int offRealY = realY - projectile.position.y;
	float length = sqrtf((offRealX*offRealX)+(offRealY*offRealY));
	float velocity = 480/1; // 480pixels/1sec
	float realMoveDuration = length/velocity;

	// Move projectile to actual endpoint
	[projectile runAction:[CCSequence actions:
						   [CCMoveTo actionWithDuration:realMoveDuration position:realDest],
						   [CCCallFuncN actionWithTarget:self selector:@selector(spriteMoveFinished:)],
						   nil]];

}

I have added self.isTouchEnabled = YES; into my init method but receive 1 error

request for member 'isTouchEnabled' in something not a structure or union

any ideas?

thanks

Posted 9 months ago #

phil_me_up
Member
This is telling you that isTouchEnabled doesn't work with this object. What is the class type used in this code? It should be attached to a CCLayer but you might have it in a CCSprite / CCNode or something else (check your h file and ensure it reads something like the below)
```
@interface InputLayer : CCLayer
```
Posted 9 months ago #

irvaz
Member

yeah i just worked it out i was using CCScene instead of CCLayer it now runs with no errors but nothing is shooting, no projectiles.
Im trying to convert this code to shoot from bottom to top as apposed to left to right but having real difficulty

//PROJECTILES

- (void)ccTouchesEnded:(NSSet *)touches withEvent:(UIEvent *)event {

	// Choose one of the touches to work with
	UITouch *touch = [touches anyObject];
	CGPoint location = [touch locationInView:[touch view]];
	location = [[CCDirector sharedDirector] convertToGL:location];

	// Set up initial location of projectile
	CGSize winSize = [[CCDirector sharedDirector] winSize];
	CCSprite *projectile = [CCSprite spriteWithFile:@"Bullet.png"
											   rect:CGRectMake(0, 0, 3, 8)];
	projectile.position = ccp(20, winSize.width/2);

	// Determine offset of location to projectile
	int offX = location.x - projectile.position.x;
	int offY = location.y - projectile.position.y;

	// Bail out if we are shooting down or backwards
	if (offX <= 0) return;

	// Ok to add now - we've double checked position
	[self addChild:projectile];

	// Determine where we wish to shoot the projectile to
	int realX = winSize.height + (projectile.contentSize.height/2);
	float ratio = (float) offY / (float) offX;
	int realY = (realX * ratio) + projectile.position.y;
	CGPoint realDest = ccp(realX, realY);

	// Determine the length of how far we're shooting
	int offRealX = realX - projectile.position.x;
	int offRealY = realY - projectile.position.y;
	float length = sqrtf((offRealX*offRealX)+(offRealY*offRealY));
	float velocity = 480/1; // 480pixels/1sec
	float realMoveDuration = length/velocity;

	// Move projectile to actual endpoint
	[projectile runAction:[CCSequence actions:
						   [CCMoveTo actionWithDuration:realMoveDuration position:realDest],
						   [CCCallFuncN actionWithTarget:self selector:@selector(spriteMoveFinished:)],
						   nil]];

}

any ideas?

thanks

Posted 9 months ago #

irvaz
Member

ok im ow at this point, i really thought id cracked it. theres no errors but no projectiles shooting on screen...

I think I get the maths behind it but trying to convert it to shoot on a different axis has got me stumped.

//PROJECTILES

- (void)ccTouchesEnded:(NSSet *)touches withEvent:(UIEvent *)event {

	// Choose one of the touches to work with
	UITouch *touch = [touches anyObject];
	CGPoint location = [touch locationInView:[touch view]];
	location = [[CCDirector sharedDirector] convertToGL:location];

	// Set up initial location of projectile
	CGSize winSize = [[CCDirector sharedDirector] winSize];
	CCSprite *projectile = [CCSprite spriteWithFile:@"Bullet.png"
											   rect:CGRectMake(0, 0, 3, 8)];
	projectile.position = ccp(8, winSize.width/2);

	// Determine offset of location to projectile
	int offSetX = location.x - projectile.position.x;
	int offSetY = location.y - projectile.position.y;

	// Bail out if we are shooting down or backwards
	if (offSetX <= 0) return;

	// Ok to add now - we've double checked position
	[self addChild:projectile];

	// Determine where we wish to shoot the projectile to
	int realY = winSize.height + (projectile.contentSize.height/2);
	float ratio = (float) offSetX / (float) offSetY;
	int realX = (realY * ratio) + projectile.position.x;
	CGPoint realDest = ccp(realY, realX);

	// Determine the length of how far we're shooting
	int offRealX = realX - projectile.position.x;
	int offRealY = realY - projectile.position.y;
	float length = sqrtf((offRealX*offRealX)+(offRealY*offRealY));
	float velocity = 480/1; // 480pixels/1sec
	float realMoveDuration = length/velocity;

	// Move projectile to actual endpoint
	[projectile runAction:[CCSequence actions:
						   [CCMoveTo actionWithDuration:realMoveDuration position:realDest],
						   [CCCallFuncN actionWithTarget:self selector:@selector(spriteMoveFinished:)],
						   nil]];

}

Posted 9 months ago #

varedis
Moderator
Try flipping your ratio around:
```
float ratio = (float) offSetY / (float) offSetX;
```
Posted 9 months ago #
irvaz
Member

hi thanks for the reply

I tried what you said but it hasn't made any difference, anymore ideas?

it took me all day yesterday just to figure out the maths but i just cant see the problem with it...

Posted 9 months ago #
irvaz
Member

Im starting to wonder if its something to do with another part of my project, I had trouble positioning sprites. when i positioned a sprite at (240,160) assuming it would be in the middle it was either in the top corner or off the screen. two of my scenes have the same sprite in exactly the same location on the screen but there .position is totally different. I have to admit I am very very new to coding so maybe i've missed something?

thanks

Posted 9 months ago #
varedis
Moderator

Are you changing the position of the layer at all?

Posted 9 months ago #

irvaz
Member

I dont think I am... Here is my code

#import "ActionScene.h"

@implementation ActionScene

+(id) scene
{
	// 'scene' is an autorelease object.
	CCScene *scene = [CCScene node];

	// 'layer' is an autorelease object.
	ActionScene *layer = [ActionScene node];

	// add layer as a child to scene
	[scene addChild: layer];

	// return the scene
	return scene;
}

////////////////////////////////////////////

-(void)spriteMoveFinished:(id)sender {
	CCSprite *sprite = (CCSprite *)sender;
	[self removeChild:sprite cleanup:YES];
}

////////////////////////////////////////////

//ENEMYS

-(void)addEnemy {

	CCSprite *enemy = [CCSprite spriteWithFile:@"enemy.png"
										   rect:CGRectMake(0, 0, 24, 84)]; 

	// Determine where to spawn the target along the X axis
	CGSize winSize = [[CCDirector sharedDirector] winSize];
	int minX = enemy.contentSize.width/2;
	int maxX = winSize.width - enemy.contentSize.width/2;
	int rangeX = maxX - minX;
	int actualX = (arc4random() % rangeX) + minX;

	// Create the target slightly off-screen along the top edge,
	// and along a random position along the X axis as calculated above
	enemy.position = ccp(actualX, winSize.height + (enemy.contentSize.height/2));
	[self addChild:enemy];	

	// Determine speed of the target
	int minDuration = 2.0;
	int maxDuration = 4.0;
	int rangeDuration = maxDuration - minDuration;
	int actualDuration = (arc4random() % rangeDuration) + minDuration;

	// Create the actions
	//Determines where the enemy will move to (bottom of the screen)
	id actionMove = [CCMoveTo actionWithDuration:actualDuration position:ccp(actualX, (-enemy.contentSize.height/2))];

	id actionMoveDone = [CCCallFuncN actionWithTarget:self
											 selector:@selector(spriteMoveFinished:)];

	[enemy runAction:[CCSequence actions:actionMove, actionMoveDone, nil]];

}

////////////////////////////////////////////

//PROJECTILES

- (void)ccTouchesEnded:(NSSet *)touches withEvent:(UIEvent *)event {

	// Choose one of the touches to work with
	UITouch *touch = [touches anyObject];
	CGPoint location = [touch locationInView:[touch view]];
	location = [[CCDirector sharedDirector] convertToGL:location];

	// Set up initial location of projectile
	CGSize winSize = [[CCDirector sharedDirector] winSize];
	CCSprite *projectile = [CCSprite spriteWithFile:@"Bullet.png"
											   rect:CGRectMake(0, 0, 3, 8)];
	projectile.position = ccp(8, winSize.width/2);

	// Determine offset of location to projectile
	int offSetX = location.x - projectile.position.x;
	int offSetY = location.y - projectile.position.y;

	// Bail out if we are shooting down or backwards
	if (offSetX <= 0) return;

	// Ok to add now - we've double checked position
	[self addChild:projectile];

	// Determine where we wish to shoot the projectile to
	int realY = winSize.height + (projectile.contentSize.height/2);
	float ratio = (float) offSetY / (float) offSetX;
	int realX = (realY * ratio) + projectile.position.x;
	CGPoint realDest = ccp(realY, realX);

	// Determine the length of how far we're shooting
	int offRealX = realX - projectile.position.x;
	int offRealY = realY - projectile.position.y;
	float length = sqrtf((offRealX*offRealX)+(offRealY*offRealY));
	float velocity = 480/1; // 480pixels/1sec
	float realMoveDuration = length/velocity;

	// Move projectile to actual endpoint
	[projectile runAction:[CCSequence actions:
						   [CCMoveTo actionWithDuration:realMoveDuration position:realDest],
						   [CCCallFuncN actionWithTarget:self selector:@selector(spriteMoveFinished:)],
						   nil]];

}

////////////////////////////////////////////

//INIT METHOD

-(id) init

{

	if( (self=[super init] )) {

		//Enable touches
		self.isTouchEnabled = YES;			

			//PLAYER
			//Adds the player to the screen with rectangle coordinates of 0, 0, 13, 32

			CGSize winSize = [[CCDirector sharedDirector] winSize];
			CCSprite *trev = [CCSprite spriteWithFile:@"Player.png"
												   rect:CGRectMake(0, 0, 13, 32)];

		    //Positions the player. The arm x axis = the width of the screen divided by 2 (puts arm in middle) the y axis = the sprites height divided by 2 

			trev.position = ccp(winSize.width/2, trev.contentSize.height/2);			

		    [self addChild:trev];		

			[self schedule:@selector(gameLogic:) interval:1.0];		

		}

	return self;
}

////////////////////////////////////////////

-(void)gameLogic:(ccTime)dt {
	[self addEnemy];
}

@end

#import "cocos2d.h"

@interface ActionScene : CCLayer  {

}

+(id)scene;

@end

Posted 9 months ago #

phil_me_up
Member

Have you made a method for spriteMoveFinished? It's a bit of a long shot but if you haven't, this might be causing a problem when running your projectile movement action (i'm sure I've seen a few cases where this hasn't cause a complete crash) - You'll see a series of errors in your debug console if this is the case.

Posted 9 months ago #
irvaz
Member

How would I go about making the method? Im following ray wenderlichs simple tutorial and i cant see that i've missed anything out.

Posted 9 months ago #
varedis
Moderator
Just noticed this:
```
projectile.position = ccp(8, winSize.width/2);
```
Looks like you have your x and y position mixed up again, this is most likely why you can't see any projectiles.
```
projectile.position = ccp(winSize.width/2, 8);
```
Ingrain this into your memory anything be it setting a position, making a CGSize or a CGRect, it is always X first and then Y.
Posted 9 months ago #
irvaz
Member

I've changed the projectile.position but still no projectiles, i just cant see the problem...

Posted 9 months ago #
varedis
Moderator
The next culprit would be, remove this line:
```
// Bail out if we are shooting down or backwards
if (offSetX <= 0) return;
```
Also do a CCLOG on realDest and see what coordinates it is sending back to you.
Posted 9 months ago #
irvaz
Member

still the same, i don't want to sound stupid but i wouldn't know where to begin adding a CCLOG? sorry

Posted 9 months ago #
varedis
Moderator
```
CCLOG(@"Real Destination: %@", NSStringFromCGPoint(realDest));
```
This will print out the value to the debugger / console when you touch the screen
Posted 9 months ago #

Gray Olson
Member

This code will get a point off screen in the right direction indefinitely:

CGSize sz = [[CCDirector sharedDirector] winSize];
	CGPoint diff = ccpSub(touchLocation, yourTank);
	float rads = atan2f( diff.y, diff.x);
	CGPoint norm =  ccpForAngle(rads);
	norm = ccpMult(norm, 1.5f * ((sz.width > sz.height)?sz.width:sz.height ));
	norm = ccpAdd(norm, touchLocation);

Then its just a matter of doing a ccmoveto to norm

Posted 9 months ago #

irvaz
Member

i ran the above and the only thing that was highlighted in the debugger was
if( (self=[super init] )) {

im not sure how to read the debugger but in the summary it says 'out of scope' if that means anything to you?

thanks again for your help, really appreciate this

Posted 9 months ago #
irvaz
Member

hi Gray thanks for that, where a bouts would i implement that into the above code?

Posted 9 months ago #
Gray Olson
Member

Replace:
// Determine offset of location to projectile
int offSetX = location.x - projectile.position.x;
int offSetY = location.y - projectile.position.y;

// Bail out if we are shooting down or backwards
if (offSetX <= 0) return;

// Ok to add now - we've double checked position
[self addChild:projectile];

// Determine where we wish to shoot the projectile to
int realY = winSize.height + (projectile.contentSize.height/2);
float ratio = (float) offSetY / (float) offSetX;
int realX = (realY * ratio) + projectile.position.x;
CGPoint realDest = ccp(realY, realX);

With it, and in the next lines replace realX/Y with norm.x/y and move to norm instead of realDest

Posted 9 months ago #
irvaz
Member

Ok I've had a break through! I changed my image and it works!! although it doesn't shoot wear I click but I guess I just need to play around with the maths. Thank you everyone for your help

Posted 9 months ago #

irvaz
Member

I tried to use your code Gray

- (void)ccTouchesEnded:(NSSet *)touches withEvent:(UIEvent *)event {

	// Choose one of the touches to work with
	UITouch *touch = [touches anyObject];
	CGPoint location = [touch locationInView:[touch view]];
	location = [[CCDirector sharedDirector] convertToGL:location];

	// Set up initial location of projectile
	CGSize winSize = [[CCDirector sharedDirector] winSize];
	CCSprite *projectile = [CCSprite spriteWithFile:@"TrevBrickArm1.png"
											   rect:CGRectMake(0, 0, 13, 32)];
	projectile.position = ccp(winSize.width/2, 32);

	CGSize sz = [[CCDirector sharedDirector] winSize];
	CGPoint diff = ccpSub(touchLocation, yourTank);
	float rads = atan2f( diff.y, diff.x);
	CGPoint norm =  ccpForAngle(rads);
	norm = ccpMult(norm, 1.5f * ((sz.width > sz.height)?sz.width:sz.height ));
	norm = ccpAdd(norm, touchLocation);

	int offRealX = norm.x - projectile.position.x;
	int offRealY = norm.y - projectile.position.y;
	float length = sqrtf((offRealX*offRealX)+(offRealY*offRealY));
	float velocity = 480/1; // 480pixels/1sec
	float realMoveDuration = length/velocity;	

	// Move projectile to actual endpoint
	[projectile runAction:[CCSequence actions:
						   [CCMoveTo actionWithDuration:realMoveDuration position:norm],
						   [CCCallFuncN actionWithTarget:self selector:@selector(spriteMoveFinished:)],
						   nil]];

}

but i get the error 'touchLocation undeclared...

Posted 9 months ago #

irvaz
Member

at last i've cracked it! what a feeling, thank you everybody :)

here is the working code

//PROJECTILES

- (void)ccTouchesEnded:(NSSet *)touches withEvent:(UIEvent *)event {

	// Choose one of the touches to work with
	UITouch *touch = [touches anyObject];
	CGPoint location = [touch locationInView:[touch view]];
	location = [[CCDirector sharedDirector] convertToGL:location];

	// Set up initial location of projectile
	CGSize winSize = [[CCDirector sharedDirector] winSize];
	CCSprite *projectile = [CCSprite spriteWithFile:@"TrevBrickArm1.png"
											   rect:CGRectMake(0, 0, 13, 32)];
	projectile.position = ccp(winSize.width/2, 32);

	// Determine offset of location to projectile
	int offY = location.y - projectile.position.y;
	int offX = location.x - projectile.position.x;

	//Bail out if we are shooting down or backwards
	if (offY <= 0) return;

	// Ok to add now - we've double checked position
	[self addChild:projectile];

	// Determine where we wish to shoot the projectile to
	int realY = winSize.height + (projectile.contentSize.height/2);
	float ratio = (float) offX / (float) offY;
	int realX = (realY * ratio) + projectile.position.x;
	CGPoint realDest = ccp(realX, realY);

	// Determine the length of how far we're shooting
	int offRealX = realX - projectile.position.x;
	int offRealY = realY - projectile.position.y;
	float length = sqrtf((offRealX*offRealX)+(offRealY*offRealY));
	float velocity = 480/1; // 480pixels/1sec
	float realMoveDuration = length/velocity;

	// Move projectile to actual endpoint
	[projectile runAction:[CCSequence actions:
						   [CCMoveTo actionWithDuration:realMoveDuration position:realDest],
						   [CCCallFuncN actionWithTarget:self selector:@selector(spriteMoveFinished:)],
						   nil]];

}

Enemy not moving in the right direction...

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