Comments on: iPhone Game Programming Tutorial Part 2- User Interaction, Simple AI, Game Logic

By: trolol

trolol — Sun, 02 Dec 2012 04:55:00 +0000

I am having trouble figuring out how to make the Tap to Begin label go away once I start the game. Wondering what part of the code i need to fix? i’m new to programming so i’m still learning the basics and trying to figure out stuff

By: Appsdeveloper2

Appsdeveloper2 — Sun, 05 Feb 2012 18:47:00 +0000

Very useful post. Thanks a lot.

By: Asda

Asda — Fri, 23 Dec 2011 23:53:00 +0000

This was happening to me, and I had to fix my timer. Check your NSTimer letter for letter with his.

By: Samrat Mazumdar

Samrat Mazumdar — Mon, 10 Oct 2011 02:52:00 +0000

I want to keep a cross icon on iTennisViewController.xib and make it a UIButton and when it is pressed it will comeout of the game. How to do that?

By: Vikas Shanbhogue

Vikas Shanbhogue — Fri, 26 Aug 2011 20:43:00 +0000

No worries .. Yeah the formatting is weird because I copied it straight out of XCode ..Â

I don’t understand why I can’t edit my comment..Â

By: Joe Griffin

Joe Griffin — Fri, 29 Jul 2011 16:37:00 +0000

Thanks for the iphone game development. With the Apple phone's extreme popularity, this is definitely a good place for those interested in the field to start out.Â

By: Callum_holland

Callum_holland — Sun, 24 Jul 2011 22:24:00 +0000

Bit confusing but i figured it out, u fixed a huge problem iv been working on with the ball getting ‘stuck’ on the racquet, thanks manÂ

By: Vikas Shanbhogue

Vikas Shanbhogue — Fri, 24 Jun 2011 20:53:00 +0000

Sorry about the messy comment .. I don’t know how to edit it.

By: Vikas Shanbhogue

Vikas Shanbhogue — Fri, 24 Jun 2011 20:50:00 +0000

Hey .. This was a great tutorial .. Very well explained.
I’m a programmer but have had a problem with how to structure games and this helped a lot.

Â I noticed a problem with your code, let me know if anyone else faced this issue.Â

p.p1 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; min-height: 13.0px}
p.p2 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; color: #401a7f}
p.p3 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; color: #508187}
p.p4 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; color: #d0271c}
p.p5 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo}
span.s1 {color: #000000}
span.s2 {color: #bb23a0}
span.s3 {color: #508187}
span.s4 {color: #733aa7}
span.s5 {color: #3523d5}
span.s6 {color: #401a7f}
span.Apple-tab-span {white-space:pre}

if (CGRectIntersectsRect(ball.frame, racquet_yellow.frame))Â
{if (ball.center.y < racquet_yellow.center.y)Â
ballVelocity.y = – ballVelocity.y;}}

So you explained the purpose of having ball.center.y < racquet_yellow.center.y. A problem I faced was that when the ball was going back in an upwards direction it would intersect with racquet_yellow.frame and meet the second if condition and keep moving back and forth.Â I faced the same problem with the green racquet.Â A simple fix is as follows:

if (CGRectIntersectsRect(ball.frame, racquet_yellow.frame)) {
if (ball.center.y 0) {
ballVelocity.y = – ballVelocity.y;
}
}This ensures that the only time the ball gets deflected is when the ball is moving towards the yellow racquet and not when it is moving away from it.Similarly for the green racquet’s if condition I would add “&& ballVelocity.y < 0 ".Â I did not watch your video but an additional note: Â To ensure that frames intersect, I would increase the height of both racquets a little (only if they don't intersect on both sides).I hope this helped rather than confused people. Also let me know if there was an easier fix!Â

By: JB

JB — Wed, 15 Jun 2011 04:04:00 +0000

I also have another problem, sometimes te ball hits the score bounds but it simply bounces and the game continues, no score detected.