Slides: iPhone Development II – Paul Solt

Demo: Triangle Demo: OpenGL ES on iPhone

OpenGL ES Triangle Demo

The first demo is a basic OpenGL ES iPhone project using vertex/color arrays and an orthogonal view. It’s based on the tutorials from Jeff LaMarche This is the starting point for any iPhone OpenGL ES project. It’ll give you a window that you can draw in and manipulate OpenGL state. Use Jeff’s xcode project template to make this process painless and easy to get started. It’s easier than using GLUT!

Demo: Cocos2D for iPhone: Cocos2D iPhone Graphics Demo

Cocos2D Demo for iPhone

A 2D graphics package to aid graphical applications on the iPhone. It provides some really neat animation support along with project templates to make setup a breeze. Cocos2D comes with two separate physics packages that you can incorporate into your game. The demo shows an animation trigger when the user pressed on the screen. Animations can be built from simple actions and combined to create a complex animation. It’s perfect for a platformer.

Demo: Raytracing on the iPhone

Raytracing with Photon Mapping

I ported my computer graphics II ray tracer from OpenGL/GLUT to OpenGL ES on the iPhone. The performance is very slow on the iPhone 3G (133-230 seconds), but that’s to be expected with the given hardware. In the simulator it can render a scene in about 15 seconds. This demo shows how the performance of the actual device is vastly different from the iPhone simulator. I’m sure I can rework portions of the ray tracer to be more efficient, but that wasn’t the goal of the quick port.

Resources:

• OpenGL: “The Red Book” OpenGL(R) Programming Guide: The Official Guide to Learning OpenGL(R), Version 2.1 (6th Edition)
• OpenGL ES Tutorials: http://iphonedevelopment.blogspot.com/2009/05/opengl-es-from-ground-up-table-of.html
• Cocos2D: http://code.google.com/p/cocos2d-iphone/

Here are the slides and Xcode projects:

Slides:  iPhone Development – Paul Solt

1. Demo: Hello World Pusher:  Foo2

2. Demo: Touch Input:  Stalker

3. Demo: Robot Remote Control:  See my previous post

*The Touch Input demo was based on a demo given during the Stanford iPhone courses available on iTunes here.

Resources:

• Cocoa Programming for Mac OS X by Aaron Hillegass (Third Edition)
• Stanford iPhone Course (cs193p.stanford.edu)
  • Search “iPhone Application Programming” in iTunes
• Beginning iPhone 3 Development: Exploring the iPhone SDK by Jeff LaMarche
  • Blog:  iphonedevelopment.blogspot.com
• iPhone Dev Center
  • developer.apple.com/iphone

Controlling a Robot over Wi-Fi

A Virtual Robot in a Virtual World

The goal of this project was to use the Player/Stage robotics code on the iPhone to communicate and control robots. I discuss how to setup the Xcode development environment. There are two example Xcode projects. The first one is an Objective-C project that wraps around the C++ Player/Stage code. The second project is a very primitive C++ program running on the iPhone without any UI. Both of these Xcode projects are fully documented and will serve as a starting point to iPhone Player/Stage development.

iPhone Player/Stage Remote Control Project: iPhonePlayerStage

Feel free to ask questions and let me know how you use the code.

Setting defaults to the default value…

I’m not sure why there isn’t a function that can set the values for me, but after digging I found someone who ran into the same dilema. I don’t want to have multiple locations with default values (code and a Settings.bundle), so I found a programmatic way to set all the default values if they haven’t been set.

- (void)registerDefaultsFromSettingsBundle {
    NSString *settingsBundle = [[NSBundle mainBundle] pathForResource:@"Settings" ofType:@"bundle"];
    if(!settingsBundle) {
        NSLog(@"Could not find Settings.bundle");
        return;
    }
 
    NSDictionary *settings = [NSDictionary dictionaryWithContentsOfFile:[settingsBundle stringByAppendingPathComponent:@"Root.plist"]];
    NSArray *preferences = [settings objectForKey:@"PreferenceSpecifiers"];
 
    NSMutableDictionary *defaultsToRegister = [[NSMutableDictionary alloc] initWithCapacity:[preferences count]];
    for(NSDictionary *prefSpecification in preferences) {
        NSString *key = [prefSpecification objectForKey:@"Key"];
        if(key) {
            [defaultsToRegister setObject:[prefSpecification objectForKey:@"DefaultValue"] forKey:key];
        }
    }
    [[NSUserDefaults standardUserDefaults] registerDefaults:defaultsToRegister];
    [defaultsToRegister release];
}

All you have to do is call the above function if one of your Standard User Defaults returns null. Make the call once your application finishes loading like so:

- (void)applicationDidFinishLaunching:(UIApplication *)application {
	// Get the application user default values
	NSUserDefaults *user = [NSUserDefaults standardUserDefaults];
	NSString *server = [user stringForKey:@"server_address"];
	if(!server) {
		// If the default value doesn't exist then we need to manually set them.
		[self registerDefaultsFromSettingsBundle];
		server = [[NSUserDefaults standardUserDefaults] stringForKey:@"server_address"];
	}
    [window addSubview:viewController.view];
    [window makeKeyAndVisible];
}

References:

• http://stackoverflow.com/questions/510216/can-you-make-the-settings-in-settings-bundle-default-even-if-you-dont-open-the-s
  
• Display code in your WordPress blog: http://wordpress.org/extend/plugins/wp-syntax/

I was using Macports 1.710 and I was attempting to install player-stage-player (2.03 2.1.2) and player-stage-stage (2.03 2.1.1) following a short guide at http://bentham.k2.t.u-tokyo.ac.jp/notebook/?p=247

If it’s your first time using macports it can take a long time. I waited 2+ hours to download/build/install dependencies

I used the command:

$ sudo port install playerstage-player playerstage-stage

However it errored out at the end with the message:

$ sudo port install playerstage-player playerstage-stage
--->  Building playerstage-player
Error: Target org.macports.build returned: shell command " cd "/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_release_ports_science_playerstage-player/work/player-2.0.4" && make all " returned error 2
Command output: building '_playerc' extension
swigging playerc.i to playerc_wrap.c
swig -python -o playerc_wrap.c playerc.i
playerc.i:44: Warning(124): Specifying the language name in %typemap is deprecated - use #ifdef SWIG<LANG> instead.
playerc.i:82: Warning(124): Specifying the language name in %typemap is deprecated - use #ifdef SWIG<LANG> instead.
playerc.i:121: Warning(124): Specifying the language name in %typemap is deprecated - use #ifdef SWIG<LANG> instead.
playerc.i:127: Warning(124): Specifying the language name in %typemap is deprecated - use #ifdef SWIG<LANG> instead.
gcc -fno-strict-aliasing -Wno-long-double -no-cpp-precomp -mno-fused-madd -fno-common -dynamic -DNDEBUG -g -Os -Wall -Wstrict-prototypes -DMACOSX -I/usr/include/ffi -DENABLE_DTRACE -arch i386 -arch ppc -pipe -I./../.. -I../../../.. -I/System/Library/Frameworks/Python.framework/Versions/2.5/include/python2.5 -c playerc_wrap.c -o build/temp.macosx-10.5-i386-2.5/playerc_wrap.o
playerc_wrap.c: In function '_wrap_playerc_mclient_client_set':
playerc_wrap.c:40301: warning: assignment from incompatible pointer type
playerc_wrap.c: In function '_wrap_playerc_mclient_addclient':
playerc_wrap.c:40504: warning: passing argument 2 of 'playerc_mclient_addclient' from incompatible pointer type
playerc_wrap.c: In function '_wrap_playerc_mclient_client_set':
playerc_wrap.c:40301: warning: assignment from incompatible pointer type
playerc_wrap.c: In function '_wrap_playerc_mclient_addclient':
playerc_wrap.c:40504: warning: passing argument 2 of 'playerc_mclient_addclient' from incompatible pointer type
gcc -Wl,-F. -bundle -undefined dynamic_lookup -arch i386 -arch ppc build/temp.macosx-10.5-i386-2.5/playerc_wrap.o -L./../../.libs -L../../../../libplayerxdr/.libs -L../../../../libplayercore/.libs -L../../../../libplayerjpeg/.libs -lplayerxdr -lplayerc -lplayerjpeg -ljpeg -lplayererror -o build/lib.macosx-10.5-i386-2.5/_playerc.so
ld: library not found for -ljpeg
collect2: ld returned 1 exit status
ld: library not found for -ljpeg
collect2: ld returned 1 exit status
lipo: can't open input file: /var/tmp//ccI9TvVp.out
(No such file or directory)
error: command 'gcc' failed with exit status 1
make[6]: *** [pythonbuild] Error 1
make[5]: *** [all] Error 2
make[4]: *** [all-recursive] Error 1
make[3]: *** [all-recursive] Error 1
make[2]: *** [all-recursive] Error 1
make[1]: *** [all-recursive] Error 1
make: *** [all] Error 2

Error: Status 1 encountered during processing.

So I searched around the MacPorts website and I came across the ticket #18891, which basically said to run the following command to change the version of python being used from 3.0 to 2.5.

$ sudo port install python_select && sudo python_select python25
Skipping org.macports.activate (python_select +darwin_9) since this
port is already active
--->  Cleaning python_select
Selecting version "python25" for python

Following that command I was able to finish installing Player/Stage via MacPorts by using the orginal port command.

$ sudo port install playerstage-player playerstage-stage
--->  Building playerstage-player
--->  Staging playerstage-player into destroot
--->  Installing playerstage-player @2.0.4_2
--->  Activating playerstage-player @2.0.4_2
--->  Cleaning playerstage-player
--->  Fetching playerstage-stage
--->  Attempting to fetch stage-2.0.3.tar.bz2 from

http://voxel.dl.sourceforge.net/playerstage

--->  Verifying checksum(s) for playerstage-stage
--->  Extracting playerstage-stage
--->  Configuring playerstage-stage
--->  Building playerstage-stage
--->  Staging playerstage-stage into destroot
--->  Installing playerstage-stage @2.0.3_0
--->  Activating playerstage-stage @2.0.3_0
--->  Cleaning playerstage-stage

I tried to use player stage from MacPorts.

$ player /opt/local/var/macports/software/playerstage-stage\
/*/opt/local/share/stage/worlds/simple.cfg

And I received the error:

rr: unable to open color database /usr/X11R6/lib/X11/rgb.txt
 : No such file or directory (stage.c stg_lookup_color)

Following the advice from http://bentham.k2.t.u-tokyo.ac.jp/notebook/?cat=5 I added the following link.

$ sudo ln -s /usr/X11/share/X11/rgb.txt /usr/X11R6/lib/X11/rgb.txt

Now I am able to create a player server and connect with a client with the commands:

$ player /opt/local/var/macports/software/playerstage-stage\
/*/opt/local/share/stage/worlds/simple.cfg

/opt/local/var/macports/software/playerstage-player\
/*/opt/local/share/player/examples/libplayerc++/laserobstacleavoid

With the ability to run player/stage I will post again on my progress as I use an iPhone to run the Player client, rather than my Macbook Pro.

Player client running on iPhone with Player/Stage.