This is exactly the kind of think I am looking for. I am totally new to Objective-C and the OSX and iPhone Frameworks. (only did windows development before)

I think pong is an excellent “hello world” for writing games as it contains many basics. As you already pointed out however it doesn’t include any animation/sprite type examples. Any chance you could toss in a small animation example? Maybe have the raquets change color or something when they collide with the ball or something simple?

I look forward to the rest of this series!

Hi Brandon!

I’m also new to the Mac “world”, your tutorial came in the right moment.

I’m having trouble though, when I run iTennis it crashes and generates a report to send to Apple. Can you help me find out what am I doing wrong? The build shows no errors nor warnings.

Thanks and keep up the good work!

Great tutorial as always. I’m looking forward to seeing more of the obscure aspects of game programming as well. Especially sound and Quartz programming on the IPhone. Thanks!

Yes! I have been searching the net for a single iPhone game tutorial! This is exactly what I need! Keep up the great work!

This is just what I was looking for! As a game developer trying to transfer my knowledge of simple game loops, this provided a really good foundation.

Please, please, please give us more

Please please please continue this wonderful tutorial! Thank you so much. I have learned a lot about Objective C by just doing this tutorial.

g

This was a great tutorial. I can’t wait for the next in the series. I will try to get the paddle working on my own until then.

Hi,
It is really a nice one,
great tutorial, cant wait for its part 2,
when it will be here on icodeblog,
thanks for all your efforts.

hi brandon,
I am waiting for the next part,
please let me know how much more time will it take,
truely i cant wait for that
for a long time i m searching for a game tutorial,
but i didnt get it, through this i will be able to learn a lot.
please reply
thanks a lot

Hi Brandon.

I’d like to see declaration & usage of objects/methods/functions… reading and passing arguments from said classes.

Most iPhone blog/books only discuss programming the interface and the books I have on cocoa are written for Mac. The code is not 100% compatible with iPhone.

For example… I have HilleGass’ book on ‘cocoa for mac’ I can write classes and function and pass arguments that work excellent on the mac but comes up with tons of errors when you try it on the iPhone.

It’s just that the syntax for the iPhone is a little different so basic examples that demonstrate how to do it would work fine.

Thanks

Hey, thanks for the tutorial. It’s a great start and put together nicely. I’m looking forward to seeing more.

Brandon,

I’m sorry you didn’t understand my first post. I was hoping you could do a primer on “How to create objects and methods – and implement them” tutorial.
I just reviewed the Fruit App and it’s a great intro. The reason I’m asking is because you are great at explaining stuff so we can understand it.

Thanks for the great tutorials!!!!

Examples of the primer:

How to create an object…
How to pass a message to an object…
Methods that return multiple values…
Methods that return no value…
Creating an instance…
How to get an object’s data…
Creating pointers to objects…

It’s a kind of ‘how to do anything with objects’ thing.

Thanks again.

Thanks for tut but the video doesnt work

@ck

Found it on google images… Not exactly sure where.

@DN

That’s a good idea… Apple has a pretty good doc on this, I think it’s called objective C primer.

@ Joe

There is, it’s actually built right in to XCode.

Press Apple-option-shift-?

This should bring up the doc. It’s not quite as good as Javadoc, but it’s still pretty helpful.

Hey, I just finished up the tutorial and when I Build and Go, I get the loading screen and then just a white background… No errors or warnings. Any ideas??

I know this will sound like a stupid question, but if you get a phone call will this app close? or is there some code you need to implement some sort of “got a phone call” method?

Hi Joe,
i tried with your code,
in touch moved are you sure

if([touch view] == raquet_yellow) {
raquet_yellow.center = touchLocation;
}

is working , i tried and debugged this condition is not getting setisfied. if you want that whenever you touch the screen and move you finger then only yellow racquet will move then replace

if([touch view ] == self.view) or if you want that when you touch then only raquet will move then try

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

UITouch *touch = [touches anyObject];
if(CGRectContainsPoint([racquet_yellow frame], [touch locationInView:self.view]))
{
[self moveSquare:racquet_yellow toPoint:[touch locationInView:self.view]];
}

Ok so I implemented some thing to work, it is working ,but you try it and make some changes as per your comfort, make your own rules. I just try to implement working of yellow racquet, ball is coming touching to yellow racquet, and diverted towards the green racquet, did not code for green racquet. so lets start. first you need to declare one more variable in tennisviewcontroller.h

IBOutlet UILabel *player_score;
declare its property like
@property(nonatomic) NSInteger pscore;

synthesize it in .n file,
synthesize pscore;

now implement
- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event{

UITouch *touch = [touches anyObject];
if(CGRectContainsPoint([racquet_yellow frame], [touch locationInView:self.view]))
{
[self moveRacquet:racquet_yellow toPoint:[touch locationInView:self.view]];
}
}

and make some changes in gameloop method.
I made it like

-(void)gameLoop{
if(gameState == kGameStateRunning)
{
ball.center = CGPointMake(ball.center.x + ballVelocity.x, ball.center.y + ballVelocity.y);
if(ball.center.x > self.view.bounds.size.width || ball.center.x self.view.bounds.size.height || ball.center.y < 0 ){
ballVelocity.y = -ballVelocity.y;
}
if(CGRectContainsPoint([racquet_yellow frame], ball.center) )
{
self.pscore += 10;
player_score.text = [NSString stringWithFormat:@"%i",self.pscore + 10];
// ballVelocity.x = -ballVelocity.x;
ballVelocity.y = -ballVelocity.y;
if(ball.center.x <= self.view.center.x)
{

ballVelocity.x = 3;
}
else
{
ballVelocity.x = -3;
}

}
}else{
if(tapToBegin.hidden){
tapToBegin.hidden = NO;
}
}

}

and here is the moveRacquet method
-(void)moveRacquet:(UIImageView *)view toPoint:(CGPoint)location{
view.center = location ;
}

declare this method in .h file like

-(void)moveRacquet:(UIImageView *)view toPoint:(CGPoint)location;

now run the project move your racquet , still there is a lot to do. please comment and correct my work.

Thanks

I completed the functionality of computer’s racquet o.e green racquet. first make a variable like pscore. declare its property and synthesize it.
open your iTennisViewController.xib file and move your green racquet to the left corner and ball from center to top left corner below your racquet . this will give you a feel that computer is serving you the ball to play make sure that ball and racquet are not overlapping,maintain some distance between them, now open iTennisViewController.m file, you already have synthesize the cscore, in view did load method
write cscore = 0;

now make changes in gameloop method. here is the code, compare it with previous.

-(void)gameLoop{
if(gameState == kGameStateRunning)
{
ball.center = CGPointMake(ball.center.x + ballVelocity.x, ball.center.y + ballVelocity.y);
if(ball.center.x > self.view.bounds.size.width || ball.center.x self.view.bounds.size.height || ball.center.y < 0 ){
ballVelocity.y = -ballVelocity.y;
}
if(ball.center.y <= self.view.center.y)
{
CGPoint ballx = CGPointMake(ball.center.x,racquet_green.center.y);
[racquet_green setCenter:ballx];
}
if(CGRectContainsPoint([racquet_green frame], ball.center))
{
cscore += 10 ;
computer_score.text = [NSString stringWithFormat:@"%i", self.cscore + 10];
ballVelocity.y = -ballVelocity.y;
if(ball.center.x <= self.view.center.x) {
ballVelocity.x = random() % 9 ;
}else{
ballVelocity.x = -(random() % 9) ;
}
}
if(CGRectContainsPoint([racquet_yellow frame], ball.center) )
{
self.pscore += 10;
player_score.text = [NSString stringWithFormat:@"%i",self.pscore + 10];
ballVelocity.y = -ballVelocity.y;
if(ball.center.x <= self.view.center.x) {
ballVelocity.x = random() % 9;
}else{
ballVelocity.x = -(random() % 9);
}

}
}else{
if(tapToBegin.hidden){
tapToBegin.hidden = NO;
}
}

}

also increase the ball’s speed

#define kBallSpeedX 10
#define kBallSpeedY 25

Thanks

When will part 2 be out? I really wana finish this.

@Rey..

If you dont want to keep it running then you dont need to worry about it.. Like i said, iPhone takes care of that by itself.

Clad,

Your problem is in the code somewhere. In order to help you you need to give more information. When you launch you application make sure your console is displayed, Run > Console or Shift Command R. This will give you debugging information about why you app is crashing on launch.

ok… fixed that problem I think, by restarting IB through xcode….wierd. Now I get this in the console…
*** Terminating app due to uncaught exception ‘NSUnknownKeyException’, reason: ‘[ setValue:forUndefinedKey:]: this class is not key value coding-compliant for the key raquet_yellow.’
Not sure what is wrong with raquet_yellow. I’ve checked the code and there are no build errors, and the connections seem ok.

@Robert
please check that you have defined properties properly, like for racquet_yellow
IBOutlet UIImageView *racquet_yellow;
then
@property(nonatomic,retain)IBOutlet UIImageView *ra……;
and in the .m file
@synthesize racquet.
check might be some spelling mistake, or pointer is not there or in .m property you have put pointer there. check for these issues.