Any how feel free to email with questions, ideas, errors or anything else you want in the FAQ at chrisd@plaidworld.com You can also find me on IRC freenode / #iphonedev as TheBunny Also My Game company is www.plaidworld.com My On going iphone game development blog is at www.bang2d.com PS: Send anyone interested in investing in an iPhone/Mobile game company our way :) Our engine is already up and running on Mac/Win/Linux and iPhone. Languages: Do I have to use ObjC on the Phone? You can freely use C / C++ on the phone. You still need to use ObjC to talk to the Cocoa APIs. Feel free to wrap C++ code in ObjC call backs / events. This page provides a summary of how Objective-C is implemented in C using Apple's Objective-C runtime. Meaning you could call methods on ObjC objects purely using C / C++ if you really wanted to. http://www.cocoadev.com/index.pl?ImplementationOfObjectiveCInC How do I turn on ObjC++ Change your file extensions to .mm Does Garbage Collection work on the phone? No. Learning Cocoa / ObjC: Iphone Dev web sites http://iphonedevsdk.com/ http://idevkit.com/ Learning Objective C a primer http://developer.apple.com/iphone/gettingstarted/docs/objectivecprimer.action;jsessionid=6FA34178B5DCC660436232BD437E9F9B.worker10 MyFirst Iphone app: http://developer.apple.com/iphone/library/navigation/index.html Under the "Getting Started" Tab Read "Creating a iPhone Application" Introduction to The Objective-C 2.0 Programming Language: http://developer.apple.com/documentation/Cocoa/Conceptual/ObjectiveC/Introduction/chapter_1_section_1.html Tutorials: http://www.cocoadev.com/index.pl?CocoaTutorials http://www.cocoadevcentral.com Books: Cocoa(R) Programming for Mac(R) OS X (3rd Edition) (Paperback) by Aaron Hillegass (Author) http://www.amazon.com/Cocoa-Programming-Mac-OS-3rd/dp/0321503619/ref=sr_1_1?ie=UTF8&s=books&qid=1216923952&sr=1-1 Programming in Objective-C (Developer's Library) (Paperback) http://www.amazon.com/Programming-Objective-C-Developers-Library-Stephen/dp/0672325861 Developer Program: 1. 1. I just applied for the iPhone Dev program how long till I get in? Well thats a trick question... back in april I got in, in 2 weeks and I had a LLC and Company account. Other people still report not being accepted since the very beginning. Since the iPhone 2 launched I believe most developer world wide are getting in pretty fast. 2. I just paid apple 99$ how long will I have to wait till I get my certs? A: Maybe 24 hours. What do I need to be able to test on the phone? You need to to pay apple 99$ after which you will be able to generate a provisioning certificate that will allow you to run code on the phone. License Agreement: Will apple let me to this on the ??? For starters read the SDK license agreement its written in very plain English. YOU CAN'T RUN SCRIPTS ON THE THE IPHONE!!!! a. You did not actually read the license did you? b. You are talking about license section 3.1 c. The sections of the license you are talking about address 2 issues. First is the use of plug ins or any kind of plug in like system. Second you will not run any "DOWNLOADED" script. d. Mouse House my games is 95% Lua and is currently for sale in the App store. Profiling: Simulator: How do I simulate multi-touch? Hold down option If you hold option in the simulator, you can pinch, as always, but if you hold shift, you can change the center point of the pinch. How do I swipe? You can also hold shift and while holding it do a two finger swipe. Hardware: Specs: http://en.wikipedia.org/wiki/IPhone CPU - 600 mhz ARM underclocked to 410 mhz FPU - YES use it! GPU - PowerVR MBX Lite 3D [24] with 24 MB of shared VRAM Screen 480x320 px, 3.5 in (89 mm), color LCD, 3:2 aspect ratio Camera 2.0 megapixel Memory 128 MB DRAM[26] Storage Flash memory 4, 8, or 16 GB How much free RAM do I really have to use? Apple told me about 40 MBs. If you have a better idea tell me? Games: What version of GLES is on the phone: OpenGL ES v1.1 Game code: GLSprite ( on web site ) CrashLanding ( on web site ) Touch Fighter 2 ( handed out at WWDC ask nicely on IRC maybe ) What is the fastest way to draw on the iphone? OpenGL. Best Practices for the GPU? Get the POWERVR MBX 3D Application Development Recommendations and POWERVR Technology Overview http://www.imgtec.com/powervr/insider/sdk/KhronosOpenGLES1xMBX.asp Tutorials: The OpenGL Red Book or NEHE is all you really need to learn GL and most of normal GL translates directly to GLES You can order the red book USED from amazon http://www.amazon.com/gp/product/0321335732/ref=s9sdps_c6_14_img2-rfc_p-frt_p-3237_p_si2?pf_rd_m=ATVPDKIKX0DER&pf_rd_s=center-1&pf_rd_r=1YV6FP34FD5SCSVGYGB9&pf_rd_t=101&pf_rd_p=463383351&pf_rd_i=507846 or here is at least 1 free HTML copy online. http://fly.srk.fer.hr/~unreal/theredbook/ Possibly a much better GL book with all the same stuff and a lot more is OpenGL(R) SuperBible: http://www.amazon.com/OpenGL-SuperBible-Comprehensive-Tutorial-Reference/dp/0321498828/ref=pd_sim_b_1 GLES http://www.imgtec.com/powervr/insider/sdk/KhronosOpenGLES2xSGX.asp http://www.zeuscmd.com/tutorials/opengles/index.php NeHe ( general OpenGL ) http://nehe.gamedev.net/ iPhone Game Engines: Shiva 3D Lua based 3D IDE host app is windows only(?) Looks Cool tho http://www.stonetrip.com/ 2D engine for iphone using python cocos2d: the PC/Mac/Linux coded in python (it doesn't work on iPhone) http://cocos2d.org iPhone version coded in objective-c http://code.google.com/p/cocos2d-iphone/ With the NDA lifted libSDL is coming to iPhone http://www.libsdl.org/ CVS http://www.libsdl.org/cgi/viewvc.cgi/trunk/ Unity3D - excellent mac/win game engine coming to iphone this week. I can highly recommend this one. I work with ith daily doing fulltime contracting work. http://unity3d.com/unity/features/iphone-publishing Torque for iphone. http://www.garagegames.com/products/torque/iphone Interestingly Oolong 3D game Engine below says iTorque uses it. I have no idea what Garage Games actually added on top of Oolong Oolong 3D game Engine Open Source http://oolongengine.com/ Used in this game http://sourceitsoftware.com/zombie.html Here is another open source engine that looks good. http://www.sio2interactive.com Games Made with it are at: http://sio2interactive.com/GAMES.html IRC channel is: sio2 How do I load a texture? See any of the above source code... There used to be a class that both loaded textures and could draw quads for you. I used it as a basis for my quad based engine. The code is plenty fast. How do I draw a tile/quad? See GLSprite code. How do I play sounds? Use OpenAL See CrashLanding for code. Also https://developer.apple.com/iphone/library/documentation/iPhone/Conceptual/iPhoneOSProgrammingGuide/AudioandVideoTechnologies/chapter_10_section_2.html How Do I play music? See touch fighter 2 code SoundEngine.cpp AudioQueue for streaming audio music Also https://developer.apple.com/iphone/library/documentation/iPhone/Conceptual/iPhoneOSProgrammingGuide/AudioandVideoTechnologies/chapter_10_section_2.html Also ins SDK 2.2 There is a new AV frameworks that lets you play music in like 4 lines of code http://arstechnica.com/journals/apple.ars/2008/11/25/iphone-sdk-watch-new-avfoundation-framework Networking: Touch Fighter 2 code. Speed issues: I solved that wifi throttling back providing high latency by sending a udp packet out every 90ms If you top >100ms, the wifi power saves and you get ping times to the ipod touch of upto 1.5 - 3 seconds. Using GL and cocoa views/layers at the same time: See how the prefs are done in the Touch Fighter 2 code. Whatshould I set my timer to? Don't use a timer. Use a thread instead for the main game loop. In some recent verison of the SDK the issues with threading GLES were fixed. You game loop should look something like this and might get a nice +10 FPS from useing threads vs Timers. - (void) applicationDidFinishLaunching:(UIApplication*)application{ // SET UP GLOBAL the_app = self; [ self my_setup ]; // TIMER //[ NSTimer scheduledTimerWithTimeInterval:( 1.0 / kFPS ) target:self selector:@selector( run_bang2d: ) userInfo:nil repeats:YES ]; // START THREAD [NSThread detachNewThreadSelector: @selector( run_bang2d_threaded: ) toTarget:self withObject:self ]; } - (void) run_bang2d_threaded:(AppController*)sender { NSAutoreleasePool* pool = [ NSAutoreleasePool new ]; // SET CURRENT GL CONTEXT FOR THREAD [ sender->_glView setCurrentContext ]; // RUN SDL / LUA LOOP bool game_over = false; // TERMINATE MAIN GAME LOOP TIMER while( game_over == false ){ //printf("RUN!\n"); game_over = iphone_main( &iphone_events ); } [pool release]; } // OLD a LOT higher then your actual desired max frame rate. If you go to high the iphone will not get input. Say 1000 FPS. If you go to low you will actually lose FPS while waiting for the timer to resume. My games is currently set to around 500 fps. If I set it to a steady 30 FPS or even 60 I lose an actual 5 FPS. YMMV of course so play with it. PNGs: Are the preferred image format on the iPhone. But they get converted by xcode. All your PNGs get converted to BGRA with Premultiplied alpha its basically an optimization to make images draw fastest but that only really applies if your using UIKit to draw them. So if you are using a PNG lib to load them instead of the iPhone APIs you need to add the build setting IPHONE_OPTIMIZE_OPTIONS=-skip-PNGs to any target that doesn't want the PNGs modified Ok Here is how you do that... Go to your projects build settings. In the lower left hand corner is a menu you icon that looks like a GEAR Choose Add User-Defined Setting Name the setting: IPHONE_OPTIMIZE_OPTIONS Set the Value to: -skip-PNGs Do a clean build and your good to go as far as I can tell. I checked my bundle here and it worked. Im not sure if you will have issues cause the icon is also not compressed and neither is the Defaults Image. more notes... 1. Rename your images to something else (eg. .ppng), and the XCode packaging tool will ignore your file. 2. According to the following link (http://www.imgtec.com/powervr/insider/sdk/KhronosOpenGLES1xMBX.asp), you need to add the following build settings definition for each target. IPHONE_OPTIMIZE_OPTIONS=-skip-PNGs 3. Teach your PNG decoder to handle Apple's CgBI format. 4. Use the Cocoa UIImage classes or the Texture2D.m class. EVEN More notes Is it possible to set an iPhone XCode project to skip the 'CompressResources' build step? Specifically, I want to skip the stage where it runs pngcrush on all of my .png files, many of which don't survive the experience in a form which my app can read. Edit: the version of pngcrush used creates png files which contain a non-standard 'mandatory, private' chunk which explicitly prevents decoding. I've modified my png reader to handle these files, but I'd still like a per-project method of skipping this step. One of the other side effects of pngcrush is that it doesn't save the colour value of transparent pixels, so alpha-ed textures show fringing at smaller mip levels. The iphone png format is described here: http://modmyi.com/wiki/index.php/Iphone_PNG_images. In short, Skip the CgBI chunk Skip the zlib headers Swap BGR to RGB channel order Edit: It appears it also premultiplies the alpha, so: Divide by alpha LandScape Mode: How do I get my GL coordinate system in landscape mode? Rotate your Camera -90 How do I open a URL in Safari from my app? [[UIApplication sharedApplication] openURL:[NSURL URLWithString:url]]; Metrics: Theres at least 2 libs Im aware that you can slap in your App and track users and metrics like time used and just about anything else you want like... how many users finished your game. http://www.pinchmedia.com Nice easy to use lib for tracking metrics in your app Im told. http://www.mobclix.com/ This site also lets you see global itunes Rankings for you app and not just itunes top 100. It also lists your rank over time. See Mouse House for instance. http://www.mobclix.com/appstore/app/role-playing/mouse-house Reviews: Theres a few sites that let you view all your itunes reviews world wide. http://www.moopf.com/appstorereviews/ http://www.costmosoft.com/ratings.php Sales Figures: Mouse House Sales http://www.bang2d.com/ Payday Roulettes http://www.veiledgames.com/blog/ http://www.medialets.com/blog/2008/07/15/app-store-pricing-by-category-score-card/ http://www.losingfight.com/blog/2008/11/07/can-you-make-a-living-off-an-iphone-app/ Ad Based Revenue: http://www.pinchmedia.com http://www.admob.com/s/solutions/iphone http://www.medialets.com/iphone/sdks.php Sound Samples: Good FREE sound sample sites. // NO LONGER FREE AS OF DEC 7th MEH :( http://www.soundsnap.com/ http://www.findsounds.com/ http://www.freesound.org/ Hacks: /////////// iphone tip of the day: start the simulator from the command line with MallocStackLogging=1, run app from xcode as usual, use leaks against your app's pid to get much more useful results than the crappy instruments stuff /////////// // To change the title of the back button when using a UINavigationItem, use this undocumented call: UINavigationItem *navCon = [self navigationItem]; [navCon setBackButtonTitle:@"Cancel"]; // This call works, but is not in the header, thus causing a "may not respond to" warning. Make the warning disappear by adding the following category: @interface UINavigationItem (Hacks) - (void)setBackButtonTitle:(NSString*)title; @end /////// To get the MinimumValueImage and MaximumValueImage to work with PSSliderSpecifier, I had to open the Settings.bundle in the Finder using "Show Package Contents" and copy the png files in there. Size didn't seem to make a difference, smaller ones worked OK. The image files need to be in the Settings.bundle. I could not get them in there using Xcode, had to do it by hand. From:  http://forums.macrumors.com/showthread.php?t=537644 //////// IAlertView, UIAlertSheet and UIAlert run non-modal To get them modal, do this: //We're exposing a private method (undocumented) @interface UIAlertView (Synthesize) - (void)setRunsModal:(BOOL)modal; @end and then call:  [alertView setRunsModal:YES] before you "show" the alertView /////// it's really cool Detects memory leaks and wrong code. Stuff that "leaks" and xcode miss It works at the llvm level http://clang.llvm.org/ Then, put this script in your project #!/bin/sh cd ~/Desktop/Projects/Svn/TouchPhysics rm -rf build ~/Desktop/OSX\ Development\ Tools/Clang/scan-build  -k -V xcodebuild (obviously change the paths) Then "Clean your Project" and recompile by running this script instead It will then popup the errors in Safari YOu don't want to run it on every build (because it takes a little longer) But just run it occasionally as you build stuff and want to do the check It's a static checker, will find missing releases Things like variables being reassigned before they are used (i.e. redudant code) Pretty cool Works great for iphone development too ////// Quentarez: here's a great tip: Quentarez: when creating a draggable view, animated the update of the position with a .01 animation Quentarez: CGPoint touchLocation = [touch locationInView:[self view]]; Quentarez: [UIView beginAnimations:nil context:nil]; Quentarez: [UIView setAnimationDuration:.01]; Quentarez: [UIView setAnimationBeginsFromCurrentState:YES]; Quentarez: [[viewTouch view] setCenter:touchLocation]; Quentarez: [UIView commitAnimations]; Quentarez: if you don't animate it, it's very jerky Quentarez: with this it's smooth as silk |