I recently downloaded the sample application, GLPaint from apple. This app showed me how to implement drawing, but now I would like to animate a image over the drawn lines. Similarly to how the application "Flight Control" works, I would like to be able to draw a path for an image and then have the image animate over this path.
any ideas?
you could create your path
CGMutablePathRef thePath = CGPathCreateMutable();
and then in the touchesBegan and touchesMoved add to your path
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event{
UITouch *touch = [touches anyObject];
if(touch){
CGPoint tapPoint = [touch locationInView: self.view];
CGPathMoveToPoint(thePath, NULL,tapPoint.x,tapPoint.y);
}
}
- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event{
UITouch *touch = [touches anyObject];
if(touch){
CGPoint tapPoint = [touch locationInView: self.view];
CGPathAddLineToPoint(thePath, NULL,tapPoint.x,tapPoint.y);
}
}
and on touchedEnded, as Joshua said, create a CAKeyframeAnimation and set its path to thePath and set the other properties of your animation (duration, etc) and apply it to your object
Look at CAKeyframeAnimation, this allows you to set a path (which is a CGPathRef) for the animation to run along.
Based on code from AtomRiot, I created a simple project on my blog. See this post, also posted a short video showing the result.
However when the animation ends, the image will somehow repositioned back to (0,0), so might need to add extra code to reset the image location after animation finished.
Plus, found that you can't change the animation once it started, have to wait for it to end before you can change it.
Hope this helps!
Related
I m new to game devloping in ios. Now I want made a game similar like "Control Air Flight" and "Air Traffic Controller" ,
where a user can draw line using their finger and an object will
follow that path
so ,anyone can guide me which is best for developing like this.Can Cocos2d is best for it? Or any thing else i have to use for this.
Also If anyone knows of a tutorial already out there or any reference link please suggest me.
Thanks in Advance.
To simply let the object follow your finger, implement touches (and just one of its methods):
- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event{
UITouch *touch = [touches anyObject];
CGPoint toPoint = [touch locationInView:self.view];
[yourObjectOutlet setCenter:toPoint];
}
Here, your object's center will follow your path, but you can adjust its anchor point by editing "toPoint" accordingly to object's frame.
EDIT
If you want to draw the path, then make the object follow that path, do like this:
//define an NSMutableArray in your header file (do not forget to alloc and init it in viewDidLoad), then:
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
//you begin a new path, clear the array
[yourPathArray removeAllObjects];
}
- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event{
UITouch *touch = [touches anyObject];
CGPoint toPoint = [touch locationInView:self.view];
//now, save each point in order to make the path
[yourPathArray addObject:[NSValue valueWithCGPoint:toPoint]];
}
Now you want to start the move:
- (IBAction)startMoving{
[self goToPointWithIndex:[NSNumber numberWithInt:0]];
}
- (void)goToPointWithIndex:(NSNumber)indexer{
int toIndex = [indexer intValue];
//extract the value from array
CGPoint toPoint = [(NSValue *)[yourPathArray objectAtIndex:toIndex] CGPointValue];
//you will repeat this method so make sure you do not get out of array's bounds
if(indexer < yourPathArray.count){
[yourObject setCenter:toPoint];
toIndex++;
//repeat the method with a new index
//this method will stop repeating as soon as this "if" gets FALSE
[self performSelector:#selector(goToPointWithIndex:) with object:[NSNumber numberWithInt:toIndex] afterDelay:0.2];
}
}
That's all!
I got an Icon of UIImageView named IconView. I want to make sure when I touch and move this Icon, its position only change inside the boundary of another UIImageView named backgroundView.
I thought after I add the IconView as the subview of backgroundView, the boundary is automatically set. But it seems to be wrong.
[backgroundView addSubview:IconView];
after this, I can still move the Icon to the outside of backgroundView.
how can I set the limitation? thanks.
You try like this,
- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event {
UITouch *touch = [[event allTouches] anyObject];
CGPoint location = [touch locationInView:self.view];
if(CGRectContainsPoint(urBoundryBackgroundImage.frame, location)) {
//do your moving stuff
}
}
What I want is that wherever user touches on iPhone screen, where I will display a pic at that place.
Can anyone help me how to get co-ordinates of the area everytime when user touches the screen?
You don't say you are using cocos2d, but you tagged your question as such. I will assume this is the case.
You need to put code in your ccTouchesEnded function. This is basically what it looks like:
-(BOOL)ccTouchesEnded:(NSSet *)touches withEvent:(UIEvent *)event {
UITouch *touch = [touches anyObject];
CGPoint location = [touch locationInView: [touch view]];
CCSprite *myImage = [CCSprite spriteWihFile: #"myImage.png"];
[myImage setPosition: location];
[self addChild: myImage];
return YES;
}
It sounds like you might need more help than that. If so, you should go to the cocos2d iphone page and look through the setup and tutorials.
I am making an application, in that I want to move the sprite in a specified region of the screen, With cocos2d I am not able to make move of sprite, I only know the method -(void)ccTouchMoved:(UITouch *)touches withEvent:(UIEvent *)event, but I don't know how to move a sprite,
can any one help me????
Thanks in advance
Try something like the following.
-(BOOL)ccTouchesMoved:(NSSet *)touches withEvent:(UIEvent *)event {
UITouch * touch = [touches anyObject];
CGPoint location = [[Director sharedDirector] convertCoordinate:
[touch locationInView:touch.view]];
[yourSprite setPosition:ccp(location.x , location.y )];
return kEventHandled;
}
Edit: If you simply want to move the sprite without a touch event simply call
[yourSprite setPosition:ccp(someX, someY)];
I am trying to build an iPhone app by using Cocos2d. And i would like to set an image to another fixed position from a fixed position by using touch as my wish(speedy, or slowly). I have got some code but it does not work properly.
so friends it will more helpful to me if i get any solution.
The question is a little fuzzy, but if you want to set the position of a CocosNode you do:
[myNode setPosition:cpv(x,y)];
If you want the node to be offset from a touch location, you can do this by implementing ccTouchesBegan:withEvent
-(BOOL)ccTouchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
UITouch *touch = [touches anyObject];
CGPoint location = [touch locationInView: [touch view]];
CGPoint convertedLocation = [[Director sharedDirector] convertCoordinate:location];
[myNode setPosition: cpv(convertedLocation.x - 100, convertedLocation.y - 100)];
return kEventHandled;
}
That will offset the CocosNode by -100,-100 to where the touch occurred.
The ccTouchesBegan:withEvent: should be implemented in your Layer, and isTouchesEnabled should be set to YES to enable touches.