iPhone, iOS 5, iPad SDK Development Tutorial and Programming Tips » Tag: programming

Tutorial: Texturing 3D Objects In OpenGL ES 2.0

John — Wed, 20 Jul 2011 18:38:31 +0000

OpenGL ES is a topic that I’ve posted about many times on this site, and I’ve been trying to keep a categorized list of OpenGL ES tutorials up to date with every OpenGL ES tutorial I’ve seen. There have not been too many OpenGL ES 2.0 tutorials to date that go beyond the absolute basics.

Previously I mentioned a good series on OpenGL ES 2.0 that gave a great overview on beginner through advanced topics with some sample code. I also mentioned a great hands on beginners OpenGL ES 2.0 tutorial from Ray Wenderlich, the creator of the Space Game Starter Kit and co-author of the Learning Cocos2D book,.

Ray has continued on with his tutorial series, and added another tutorial explaining how to texture objects in OpenGL ES 2.0 on iOS devices. Texturing may sound like something simple, but the process of loading in the textures, and extracting the data from memory makes things somewhat stick on the iPhone and iPad.

You can find the tutorial here:
OpenGL ES 2.0 for iPhone Tutorial Part 2: Textures

Definitely some very handy snippets of code if you ever need to do your own texturing in OpenGL ES 2.0.

Added To The: Categorized OpenGL ES Tutorial Collection

. Tags: Graphics, programming, opengl, texture objects, opengl es 2.0, ios (apple), iPhone, opengl es, ipad

Open Source: Real-Time Congress App Phonegap And Native Source Code

John — Tue, 19 Jul 2011 19:25:03 +0000

As you may have noticed I like to keep a list on this site of open source ios apps.

Earlier I received a submission of the url to an open source iPhone app that updates on what is happening at the US congress in real time, and provides access to data about members of the US Congress.

Politics aside, it provides an example of an app that retrieves and organizes data from an online source, and there is also a Phonegap version if you are looking for any html/javascript enthusiasts out there looking for a starting point trying to build with Phonegap.

You can find the source code for the newer native version here:
https://github.com/sunlightlabs/realtimecongress-ios

The source code for the previous Phonegap version can be found here:
https://github.com/sunlightlabs/real_time_congress-iphone_html

You can find the app on iTunes here.

I’ll be adding it to the list of open source apps soon.

. Tags: github, itunes, source code, phonegap, native source code, programming, iPhone, open source

Best Resources In iOS Development – July 18th 2011

John — Mon, 18 Jul 2011 06:13:27 +0000

Another excellent week to be an iOS developer, and some big news in the department of iOS game development with the release of Cocos2D V1.0.0 and the opening of the Moai SDK beta to everyone. Also some great open source libraries and tutorials were shared.

If you have written a tutorial, open source library or tool that you would like to share you can submit the url here.

I’ve been contacted a number of times about advertising on this site so I decided to add support for BuySellAds, and added a section for small button ads. If interested you can check out the advertising page here.

Here are the resources from the last week in order of popularity:

Open Source: Easy Multistroke and Single Stroke Complex Gesture Recognition On iOS - A couple of great libraries if you are looking to quickly implement complex gesture within your app.

Open Source: iCade Library For Easy Integration In iOS Games - Library that allows you to easily support the iCade classic arcade box/controller for iPad. Makes a good example if you are trying to support a specific bluetooth interfacing device.

Tutorial: Manipulating Images With Touch Gestures - A tutorial with sample code demonstrating how to add touch features for image manipulation.

Tutorial: iOS Map Kit For Beginners Guide - A getting started tutorial for those beginning with the iOS map kit including a tutorial on displaying data from XML locations on a map without using any libraries outside of those included with the iOS SDK.

Open Source: Active Record For Core Data Library - A great open source project modeled after Ruby On Rail’s ActiveRecord for more straightforward data retrieval.

News: Cocos2D Game Engine v1.0.0 Released - News about the highly popular Cocos2D game engine finally reaching the v1.0.0 release.

Tutorial: iOS Multithreading With Grand Central Dispatch (GCD) Basics - An excellent step by step guide beginning with the basics on multithreading with iOS ‘s Grand Central Dispatch.

News: Moai SDK Game Development Kit Made Available To All - The lua based open source Moai SDK has now opened the beta for anyone to download and use.

Tutorial: Calculator App Style Glossy Buttons With Core Graphics - An explanation of the technique used to create buttons just like the calculator applications that come with iOS devices.

Tutorial: How To Use The iOS Keychain To Store Names And Passwords - A guide on using the iOS keychain in order to securely store usernames and passwords.

Thanks for reading, please bookmark and share this post!

. Tags: Cocos2D V1.0.0, data retrieval, games library, multithreading, bluetooth, gesture recognition, icade, programming, classic arcade, open source libraries

Tutorial: iOS Map Kit For Beginners Guide

John — Thu, 14 Jul 2011 18:56:17 +0000

In the recent past I mentioned a great open source example for beginners interested in using the Map Kit on iOS devices, and utilizing several open source projects.

I’ve come across a couple of excellent beginners tutorial on how to parse an XML feed, and display the contents on the map. Another giving a good explanation of the Map Kit class and several code snippets for solving common Map Kit problems. These tutorials take a different approach form the open source example that I mentioned, and no libraries outside of the iOS sdk are used.

The tutorials are from Azam Sharp and can be found in 2 parts here:

Introduction to MapKit Framework for iPhone Development

Consuming XML Feed and Displaying Public Information on the MapView Control

Great stuff if you are just beginning to use the iOS Map Kit.

. Tags: mapkit, ios, programming, map, example, tutorial

Open Source: Easily Extensible Objective-C Math Parser Library

John — Sun, 10 Jul 2011 02:39:12 +0000

Math parsing libraries can be extremely useful whenever you want to evaluate a complex mathematical expression. In Objective-C you can use NSPredicate. If you want to extend the functionality of NSPredicate however, this can be extremely difficult.

I came across a math parser that provides many advantages over NSPredicate, and other existing math libraries with in my opinion the key feature being the ease at which you can register new functions.

The library is DDMathParser from DaveDeLong. The Github for the library can be found here:
https://github.com/davedelong

You can also read Dave’s extensive writeup on the library on his website here:
Parsing Mathematical Expressions

There are many other advantages of using Dave’s library over NSPredicate and other existing math parser’s in his writeup.

Looks like the right choice if you need to go beyond the default functionality provided by NSPredicate.

. Tags: programming, core text, open source, coretext, ipad, iPhone, rich text editor

Update: Balloon Game Tutorial In Xcode 4

John — Thu, 05 May 2011 03:37:34 +0000

Recently I received a few comments and e-mails stating that the beginner’s game programming tutorial featured on this site had issues when running with Xcode 4. I decided to test things out, and had no issues when running the tutorial in Xcode 4 with the latest release version of the SDK.

You can see a screenshot of the game running in Xcode 4 and the simulator below.

The issues may have to do with some still running an older version of Xcode, possibly a beta version. Be sure to update to the latest version available in Apple’s developer website, and if you don’t have access to download the latest version of Xcode 4 you can find it available in the app store for $4.99 here.

If you still receive an error when running the tutorial even wit the latest version of the SDK, please state the error within Xcode.

Thanks!

. Tags: tutorial, languages, programming, xcode, apple, game, ios

iPhone Balloon Game Programming Tutorial: Adding Retina Display Support

John — Fri, 11 Feb 2011 02:38:56 +0000

I have had several requests for updates to the iPhone action game programming tutorial, and among them was an update for retina display support. So here is the process step-by-step for those looking to add retina display support to a game made with the Sparrow Framework.

This update goes through the process of creating the new images for the game, and updating the source code so that the images display at high resolution on the retina display.

Fortunately the Sparrow Framework makes it very easy for us to do this, and handles most of the required programming automatically.

Project Files

You can download the project files leading up to this tutorial here.

You can download the project including the HD images and retina display support here.

For those who prefer Github you can find the project here, the completed project is in the 7-BalloonGameTutorial folder.

Step 1 – Making The Images

Since my initial images were created for the smaller iPhone display size I needed to scale them up to twice their original size.

I decided to use a tool called SmillaEnlarger to do this, a free open source tool that uses a fractal algorithm to scale up images. In my testing it has actually done better on the types of images (non-photos) that I need to scale up, and the end result looks considerably better than using any of the filters built into Photoshop. I have even seen it stated that SmillaEnlarger provides better results than expensive Photoshop plugins.

You can find SmillaEnlarger here.

You simply drag and drop the images with enlargement selected and a scale of 200%. In order to use the larger display support of the Sparrow Framework you will need to add @2x to the name of your images.

In my settings with SmillaEnlarger for non-photographis I simply turned all the extra adjustments down to zero.

Do that for each image in the project. After doing that I suggest re-saving the images after opening them in preview, not essential, but SmillaEnlarger tends to make oversized files.

Step 2 – Add Images Into The Xcode Project

For this step you can simply drag all the created images into the Xcode project under resources where all the original files are.

You can also add the images by ctrl-clicking and then selecting add resources, select the images, and import them into the project.

Step 3 – Turn On High Resolution Support In Game

The Sparrow Framework simply requires you to add one line of code at this point into the applicationDidFinishLaunch: method of your app delegate.

So open up BalloonGameTutorialAppDelegate.m, and in the first line within the applicationDidFinishLaunching: method add:

[SPStage setSupportHighResolutions:YES;

Your applicationDidFinishLaunching: method should now look similar to this:

- (void)applicationDidFinishLaunching:(UIApplication *)application {

// Enable retina display support
[SPStage setSupportHighResolutions:YES];

SP_CREATE_POOL(pool);

Game *game = [[Game alloc] initWithWidth:320 height:480];
sparrowView.stage = game;
[sparrowView start];
[window makeKeyAndVisible];
[game release];

[SPAudioEngine start];

SP_RELEASE_POOL(pool);
}

Now Build and Run the project, and you should be able to see the game running in retina display mode, I added the words High Definition to the images included with the project to illustrate that the new higher definition images are indeed displaying. You can also select Window->Scale->100% to make your simulator display 1:1 for the iPhone’s resolution which makes it excessively large, but allows you to easily see HD is indeed working.

Conclusion

If you cannot see the words high definition you may have the retina screen turned off in the simulator, which means that in the Mac OS X menu you need to make sure Hardware->Device->Phone (Retina) is selected.

That is all there is to it, it is a very painless process with the Sparrow Framework.

The first tutorial in this series can be found here:
iPhone Balloon Game Programming Tutorial

You might be wondering why I didn’t pack the images using texture packer like in the Sparrow Framework’s tutorial on hd support. My reason for that is simply because we’re still adding images to the project, and rather than pack the images over and over again we will do that when we add the finishing touches to the project.

In the next tutorial we will add menus to the game.

. Tags: smilla enlarge, programming, iPhone, github, xcode, retina display, action game

Tool: Objective-C Code Generator For Faster App Development

John — Thu, 10 Feb 2011 08:06:01 +0000

Found a very interesting tool that I have been using today that is absolutely brilliant for anyone programming in Objective-C on iOS and Mac. The tool is known as Accesorizer.

What this tool does is allow you to generate repetitive Objective-C code using fully customizable parameters. It’s tough to explain exactly what this tool does as it is completely different from anything I have used before, and it will take awhile for me to exploit the power of this tool.

If I did have to explain it though, I would call it super code complete on steroids.

Looking through the quick start guide should give you a very good idea about the coolness of this tool.

This video from the creator might make things a bit clearer (sorry it’s a download – previous Youtube video was removed):
Accessorizer Demo Video

You can find a trial version on the Accessorizer homepage which lasts for 30 days.

A great timesaving tool for sure.

[via Cerebral Gardens]

. Tags: programming, iPhone, apple, app store, ios, objective-c, mac os x

Open Source: Restkit Library For Easier Communication With RESTful Web Services

John — Mon, 07 Feb 2011 20:09:06 +0000

Communicating web services can be a pain on iOS. Some of the Cocoa classes for web communication are not available which doesn’t help. Fortunately there are a number of open source projects that have made things easier for communicating with web services in Objective-C.

One such project is Restkit, and what Restkit provides is a very high level framework for communicating with RESTful services. Restkit works on the iOS and Mac OS X platforms. What really makes Restkit different from the similar projects out there is simpler usage syntax, and direct integration with Core Data so you can easily persist remotely loaded objects locally.

There are some great examples on Git included with Restkit demonstrating usage with a message board built in Ruby on Rails, an example of how to communicate with Twitter, and a step by step tutorial demonstrating commonly used functionality.

You can find the homepage of Restkit here:
Restkit

The Github project can be found here:

https://github.com/twotoasters/RestKit/tree/master/Examples

Looks like a great framework for those looking to integrate Restful web services into their apps as quickly as possible.

. Tags: objective-c, iPhone, programming, github, ios (apple), languages, twitter, open source

iPhone Math Library – Open Source 400%+ Faster

John — Fri, 20 Aug 2010 19:55:29 +0000

If you’re app makes extensive use of trigonometry (and if you’re working on game development then you probably are) then you probably make extensive use of the built in math functions. This isn’t the first open source iPhone math library to offer a speed increase, but it is the only one as far as I know that is still in active development.

According to Apple apps that make extensive use of floating point numbers should not make use of the thumb compiling option which reduces code size.

Dave Dribin has created a math library exclusively making use of integers, and based on the speed of the sine function vs. the standard libary sin and sinf functions it looks like Dave’s trigint library is at least 4x faster.

You can find the library and more info here:
Trigint: An Integer-Based Trigonmetry Library

Thanks for reading, please share this using the buttons below!

[via: Under The Bridge]

. Tags: programming, development, ipad, ios, sine function, math library, developers, iPhone, trigint, lib