OpenGL ES is one of the more complex topics that I’ve covered on this blog.  I’ve mentioned some excellent OpenGL ES 2.0 tutorials for absolute beginners, and going from beginner to advanced covering topics such as basic texturing, and shader creation.

Today I came across a new app that is both helpful for beginners learning OpenGL ES 2.0, and for more advanced OpenGL ES developers looking tweaking their vertex and fragment shaders.  There are a number of OpenGL ES 2.0 coding examples included with the app.

Something really fun that you can do with this app is create animated video filters and view the results instantly using your iOS device.

The app is GLSL Studio  and you can read more about the many other things you can do with this app on the homepage.

The app was created by Mode80 who appears to be fiddling around with quite a few interesting projects.

Looks like a great app for learning and developing with OpenGL ES 2.0.

[via @rwenderlich @airjordan12345 and @triptych]

©2012 iPhone, iOS 5, iPad SDK Development Tutorial and Programming Tips. All Rights Reserved.

Yesterday I mentioned a good hands-on OpenGL ES tutorial for absolute beginners to OpenGL ES 2.0.

For information on OpenGL ES 2.0 with GLKit please visit the GLKit tutorial page.

I received a message about another set of iOS OpenGL ES tutorials covering many different topics in-depth.  If you have trouble grasping some of the concepts then this could definitely be for you.

This one is not as hands-on as the tutorial I mentioned yesterday – covering many topics from a more abstract point of view (which some will prefer). In addition to the beginner concepts also gets into many more advanced concepts  with a multitude of very useful code snippets, and diagrams.

You can find the tutorials in the OpenGL ES tutorial collection, and on the developer’s website here (split into 3 parts):
Basic concepts of 3D world and OpenGL (Beginners)
OpenGL ES 2.0 in depth (Intermediate)
Jedi skills in OpenGL ES 2.0 and 2D graphics (Advanced)

A very good set of tutorials for those learning OpenGL ES – also depending on when you read this you may want to check out the OpenGL ES Tutorial And Guide page where I am attempting to organize the many OpenGL ES posts made on this site in the last two years.

©2012 iPhone, iOS 5, iPad SDK Development Tutorial and Programming Tips. All Rights Reserved.

OpenGL ES was at one time the most popular topic on the site, but that topic began to fall to the wayside somewhat because of the improvements in different iPhone game engines, and because of the perceived increase in complexity between OpenGL ES 1.1, and OpenGL ES 2.0.

For information on OpenGL ES 2.0 with GLKit please visit the GLKit tutorial page.

That being said, Ray Wenderlich has created a solid tutorial that goes from the absolute beginning of learning OpenGL ES 2.0 through to the creation of a simple beginners tutorial.

What I like about the tutorial is that it starts from absolute scratch, and from the ground up is built to work with OpenGL ES 2.0.

I have added the tutorial to the Categorized OpenGL ES Tutorial Collection, and I have begun working on an OpenGL ES Tutorial And Guide page where I hope to aggregate the info from the many OpenGL ES related posts that have been on this site (be sure to post any beginner related questions there!) – it’s just getting started, but look for more additions soon.

You can find this tutorial on Ray’s site here:
Beginner OpenGL ES 2.0 Tutorial

If you have ever wanted to enter the world of OpenGL ES 2.0 programming this is a great starting point.

©2012 iPhone, iOS 5, iPad SDK Development Tutorial and Programming Tips. All Rights Reserved.

Since the new rules about scripting languages, I’ve seen quite a few searches here on the blog for Lua and received an e-mail over the weekend about embedding Lua into an iPhone or iPad app . This is not surprising since Lua is a scripting language that is commonly used as a scripting language in major commercial game engines.

In the past I’ve mentioned iPhone Wax which allows you to use Objective-C code in Lua scripts without first registering functions.

iPhone Wax a great project, however what if you wanted to take a more lightweight approach, and embed Lua yourself?

A quick tutorial on how to do just that has been written by GRZ Mobile and can be found here:
Integrating Lua Into An iPhone App

The tutorial goes through the process of embedding Lua within an iPhone application and provides sample code.  However, it does not cover the process of how to integrate Lua with C functions but that is covered in the C functions section of the Lua programming guide.

Seeing how time consuming the integration process can be really helps me to appreciate the iPhone Wax project.

©2012 iPhone, iOS 5, iPad SDK Development Tutorial and Programming Tips. All Rights Reserved.

Apple has recently released a couple of terrific videos on iPhone OpenGL ES from their Tech Talk.  I haven’t finished watching the videos, but already had some takeaways that I’m going to implement immediately.

You can get the videos free here on iTunes: Advanced Videos From Apple

You’ll definitely want to check them out if you haven’t already.

©2012 iPhone, iOS 5, iPad SDK Development Tutorial and Programming Tips. All Rights Reserved.

Drawing a 2D Hud on a 3D OpenGL ES scene is a common task when developing games.

To do this without any distortion in OpenGL ES you need to draw your HUD through a matrix different from the projection matrix used for 3D objects.

Jeff LaMarche, co-author of Beginning iPhone 3 Development, and More iPhone development has added a new tutorial on Drawing a Hud Display in OpenGL ES.

In the tutorial Jeff takes you through the process of adding a simple HUD to a 3D Scene.

Be sure to check out the iPhone OpenGL ES resources list for more OpenGL ES resources.

source Jeff LaMarche’s Blog

©2012 iPhone, iOS 5, iPad SDK Development Tutorial and Programming Tips. All Rights Reserved.

Updating this old list with a few changes.  A lot has happened in the Unity 3D community since I created this list: a basic Unity 3D is now free for Mac development, and DiamondTearz blog is no more, but has been changed to another site known as InfiniteUnity3D

Official Unity Resources – This is a wide collection of Unity iPhone resources including tutorials, sample projects, and the like.  The Unity 3D people have really done a great job putting all this together.  It’s really second to none when you look at the resources available for other iPhone game engines.  The place to start is the videos. I think this is a great example of what other engine/game creators should try to put together.

Infinite Unity 3D – This is a terrific resource, the creator who ran the DiamondTearz blog previously has now created this site exclusively for helping Unity 3D users.

Learn Unity 3D – Another great resource for Unity 3D info with some great video tutorials. The video tutorials along with some great Photoshop/PHP/Indesign tutorials can be found on Learn Me Silly.

UnifyCommunity Wiki – A great wiki that is a tremendous resource for those developing with Unity 3D.

Those are the most helpful resources that I’ve found for dealing with the Unity iPhone game engine, as I said the documentation/examples are extensive on the Unity 3D site so you will want to start with those, but it can be great to find other perspectives.

The engine has also made great strides since their initial iPhone release so if you didn’t like it initially (there were some performance issues that seem to have been alleviated) you will probably want to check into it again as it has really become the market leader for 3D game creation tools on the iPhone.  The iPhone version offers a free trial.

©2012 iPhone, iOS 5, iPad SDK Development Tutorial and Programming Tips. All Rights Reserved.

An excellent iPhone OpenGL ES animation tutorial has been created by Jeff LaMarche covering the concepts of keyframing, interpolation, and creating a looping animation in OpenGL ES.

In the tutorial Jeff uses a simple 3D ball model created in Blender and exported using a custom script (available on the samepage) and goes into great deal explaining the entire process.

You can find the tutorial here along with all the neccessary files including the Blender 3D model exporting script here:
Fundamentals of Animation and Keyframe Animation

I really like this tutorial as Jeff uses the simplest techniques, and explains them in a very straightforward fashion.

It’s good stuff.

Here’s some other OpenGL ES Tutorials, and my list of iPhone OpenGL ES resources.

©2012 iPhone, iOS 5, iPad SDK Development Tutorial and Programming Tips. All Rights Reserved.

OpenGL ES is the graphics API used for programming the iPhone.  If want to create your own game engine, design a game from scratch, or create some other graphically intensive app that requires you to go beyond Core Animation and Quartz, then you will need to have a good understanding of OpenGL ES.  I updated this list previously upon the release of the OpenGL ES 2.0 capable iPhone 3GS, and since then I’ve received a few messages about some of the resources being updated, and found a couple new resources that i have listed below.  If you want to have an understanding, or just want to see if learning OpenGL ES is your cup of tea then you will want to check out these resources.

Math Resources

If you don’t have a basic understanding of 2D and 3D math for computer graphics your head will probably explode once you try learning OpenGL.  To prevent that from happening you should at least understand the terminology, and the reasons why this math is needed.  No need to grind through math problems like in college.. that’s what computers are for.

1. The Black Art of 3D Game Programming Chapter 10 This is a great introduction to graphics math, and really tells you what you need to know about 3D math without getting into what doesn’t really matter.  What I really love about this book is that unlike most similar books this is not a textbook, but rather designed for personal learning which makes a huge difference.The whole book can be found here for free.  It is an old book, but the math still holds true.

2. Vector & Matrix Math Tutorial If you feel that everything in the resource above is flying above your head then you probably will want to take a look at this.  I normally wouldn’t reccomend a resource that brags about being “book sized”, but it is very good.

iPhone Specific OpenGL ES 2.0 Resources

3. The OpenGL ES Shading Language This is a free pdf book from Khronos, and actually a really good read, and will teach you what you need to know, again don’t try this until you at least have some OpenGL understanding or your head may explode. Thanks to Bill Dudney one of the authors of iPhone SDK Development for pointing this out.

4. Hello Triangle: An OpenGL ES 2.0 Example – This is a sample chapter from the OpenGL ES 2.0 Programming Guide.  If you’re thinking of getting this book you will probably want to check this out to see if the book is for you as it is, how should I say this… rather academic.

5. The OpenGL ES Programming Book This code from this book has been updated to run on the iPhone and can be found here, and you’ll probably want it if you go through the chapter listed above.  Make sure you have a solid understanding of OpenGL (or OpenGL ES 1.x) before starting this book.  Now it might seem odd to put a paper book here, but you can learn alot from the sample code, and what’s given from the book.

6. The Oolong Engine An Open source 3D OpenGL ES Game Engine for Iphone, MIT licensed. Written by Wolfgang Engel former Rockstar Games programmer, and author of some intense DirectX books.  Great to see the libraries in here for handling memory, loading 3d models, performing math, and now code is rapidly being added for support of OpenGL ES 2.0 features.

7. Getting Started with OpenGL ES 2.0 on iPhone 3GS A getting started with OpenGL ES 2.0 tutorial that explains some of the most basic differences between OpenGL ES 1.1 and 2.0.

iPhone Specific OpenGL ES 1.1 Resources

8. iPhone OpenGL ES Tutorial Series (link currently dead – hopefully a new repository for these tutorials will crop up soon.)  I don’t know if Maurice Simon is the smartest person alive, but this is the smartest set of OpenGL ES tutorials I’ve seen.  A terrific resource.

9.  Jeff LaMarche’s iPhone Blog Blog from one of the authors of the excellent Beginning iPhone Development book with many articles on OpenGL ES, and an ongoing OpenGL ES from The Ground Up series.

10. SIO2 Engine this is an excellent Open Source 3D OpenGL ES engine, look at the code, understand, and maybe even use the engine rather than write your own from the ground up (nothing wrong with that).

11. Cocos2D Iphone This is an excellent Open Source 2D OpenGL ES Game Framework for iPhone you can learn alot from going in and looking around the code.  As far as Open Source frameworks go this extremely easy to use, well documented, and has an active community.

12. SDL for iPhone (SDL Version 1.3) The SDL library has been a popular open source library for probably over a decade, and has been used in many games. This is the iPhone port, and a great resource.

Non-iPhone OpenGL ES 1.x Resources

If you use these resources you’ll need to put in some time to get things running on the iPhone, but they are still excellent.

13. Nehe Tutorials Converted To OpenGL ES Michael Gorchak creator of the GluES library has put together this collection of tutorials converted from their original Nehe form.  In case you haven’t heard of them the Nehe tutorials were the definitive free tutorials for learning OpenGL.  Michael has done an excellent job of writing comments for these tutorials.  These tutorials have been updated as of late, and more has been added so be sure to check it out.

14. Khronos OpenGL ES Page This is the OpenGL ES “homepage” on which you will find the reference manual, and lots of examples.  Not specifically IPhone, but there are some great examples here and even a complete racing game BSD licensed.

15. Khronos OpenGL ES 1.x Step-By-Step Tutorials This page is from Imagination Technologies makers of the Iphone GPU, and it contains the Khronos tutorials converted to OpenGL ES and created for the PowerVR technology.  Good to lean from especially as to how they load Pod files.

16. Zeus CMD OpenGL ES Tutorials This site contains 25 Great OpenGL ES Tutorials and they are extremely well paced, this was a site I learned alot from.

17. Typhoon Labs OpenGL ES Tutorials Another excellent set of OpenGL ES tutorials if you’re addicted to tutorials you might want to check these out too.

Interesting OpenGL ES Related Sites

18. GLBenchmark This is a just an interesting site that compares the different mobile devices available that utilize OpenGL ES.  At this point it’s only showing OpenGL 1.1, but you can see how much faster a 3GS is than a 3G even at this stage.

This is just a quick video on an approach to getting started with iPhone OpenGL ES, emphasizing that it’s helpful to start with learning 3D math:

That’s the latest version of the list, be sure to post below if you find out about any other useful OpenGL ES resources.

©2012 iPhone, iOS 5, iPad SDK Development Tutorial and Programming Tips. All Rights Reserved.

I’ve made quite a few posts about OpenGL ES, and the available game engines on the iPhone, and I’d like to iterate that you do not need to use OpenGL ES or any game engine.  Core Animation can be used for iPhone game development, and if you’re used to Objective-C/Cocoa it may be the easiest route.

There are some caveats to using Core Animation, for one, you can get better performance from using raw OpenGL ES, and it can be somewhat tedious to use in instances where you may want to micromanage the animation of a graphical object.  Also, while there are 3D transformations available Core Animation is designed for 2D graphics.  All this being said, Core Animation is great for games such as card games, and board games.  A huge advantage of Core Animation is that you can lay out your components using interface builder which can be a real time saver, as all the graphical components are inherited from UIView.

You wil want to check out the manual on Apple’s official Core Animation Programming Guide here:
Core Animation Programming Guide

While much of that guide is for Mac, you can also check out the Core Animation Cookbook:
Core Animation Cookbook

As far as code samples go the best example I’ve seen is the fantastic Geek Game Board, and an iPhone compatible version with some updates beyond the Mac version available at the Apple site is here:
http://bitbucket.org/snej/geekgameboard/

and for those who have trouble downloading the source can find it here:
Geek Game Board From Bit Bucket

I was able to get this example compiling to iPhone OS 3.0 straight out.

I also have some examples on doing some simple animation that can be used in iPhone game development here:
Easy Fading Buttons and Images
Scaling Images & Button

What makes the GeekGameBoard example so good is that it includes board games, and card games (specifically Go, TicTacToe, Hex, and Klondike) that you can use as a framework which includes cards, boards, and pieces that you can use in iPhone game development.  This should get you off to a very fast start.

©2012 iPhone, iOS 5, iPad SDK Development Tutorial and Programming Tips. All Rights Reserved.