1. Sound Effects The library Cocosdenshion subproject of cocos2d-iphone targeted at game audio needs Sound effects can be loaded at application startup, so there's no delay during play http://www.cocos2d- iphone.org/wiki/doku.php/cocosdenshion:faq

2. What we have so far... Source files: AsteroidsAppDelegate.h/m implements UIApplicationDelegate AsteroidScene.h/m is-a CCLayer (the game layer), and implements CCTargetedTouchDelegate

3. What we will add... Include the.wav files in the 'Resources' Group (crtl-click → Add → Existing Files) Import 'SimpleAudioEngine' in AsteroidsScene.h to have access to the API Make a '#define' for.wav files in AsteroidsScene.h to reference them in multiple places Preload the.wav files in AsteroidsAppDelegate applicationDidFinishLaunching Play the.wav effects where needed

4. AsteroidScene.h... // Importing Chipmunk headers #import "chipmunk.h" #import "SimpleAudioEngine.h" // // All of these wav files are preloaded in AsteroidsAppDelegate.m in // AsteroidsAppDelegate::applicationDidFinishLaunching // These wav files were maked as 'Public domain' and downloaded from // http://simplythebest.net/sounds/WAV/http://simplythebest.net/sounds/WAV/ #define MISSILE_HIT_ASTEROID_WAV @"explosion.wav" #define MISSILE_FIRED_WAV @"cork_pop.wav" enum CollisionTypes {...

5. AsteroidAppDelegate.m @synthesize window; - (void) applicationDidFinishLaunching:(UIApplication*)application { … // Turn on multiple touches EAGLView *view = [director openGLView]; [view setMultipleTouchEnabled:YES]; // Default texture format for PNG/BMP/TIFF/JPEG/GIF images // It can be RGBA8888, RGBA4444, RGB5_A1, RGB565 // You can change anytime. [CCTexture2D setDefaultAlphaPixelFormat:kTexture2DPixelFormat_RGBA8888]; [[SimpleAudioEngine sharedEngine] preloadEffect: MISSILE_HIT_ASTEROID_WAV]; [[SimpleAudioEngine sharedEngine] preloadEffect: MISSILE_FIRED_WAV]; [[CCDirector sharedDirector] runWithScene: [AsteroidsScene scene]]; }

6. AsteroidScene.m // Handler called by Chipmunk Physics when it detects a collision between two registered objects. // In this case a Missile and an Asterois. int beginMissileHitAsteroid(cpArbiter *arb, cpSpace *space, void *data __attribute__ ((unused))) { NSLog(@"missileHitAsteroid!!!\n"); // Add code here to break up the asteroid if it's hasn't reached it's smallest size (in this // case remove it). Quite important to note that you need to use 'post-step' callbacks to add or remove // objects from the space. You CAN"T do it in a callback like this one. see... // http://files.slembcke.net/chipmunk/release/ChipmunkLatest-Docs/examples.html#CollisionCallbackshttp://files.slembcke.net/chipmunk/release/ChipmunkLatest-Docs/examples.html#CollisionCallbacks // Get the cpShapes involved in the collision // The order will be the same as you defined in the handler definition cpShape *missileShape, *asteroidShape; cpArbiterGetShapes(arb, &missileShape, &asteroidShape); // Add a post step callback to safely remove the body and shape from the space. // Calling cpSpaceRemove*() directly from a collision handler callback can cause crashes. // You can only register one post step callback per object. cpSpaceAddPostStepCallback(space, (cpPostStepFunc)postStepDistroyAsteroid, asteroidShape, NULL); cpSpaceAddPostStepCallback(space, (cpPostStepFunc)postStepDistroyMissile, missileShape, NULL); [[SimpleAudioEngine sharedEngine] playEffect:MISSILE_HIT_ASTEROID_WAV]; // The object is dead, don't process the collision further return 0; }

7. AsteroidScene.m // Invoked when the finger leaves the screen... - (void)ccTouchEnded:(UITouch *)touch withEvent:(UIEvent *)event { CGPoint loc = [touch locationInView: [touch view]]; loc = [[CCDirector sharedDirector] convertToGL: loc]; cpVect p = shipBody->p; NSLog(@"ccTouchEnded shipBody loc touchMoved %@\n", p.x, p.y, loc.x, loc.y, (touchMoved ? @"Y" : @"N")); // If there was a "move" during this touch, then fire the thrusters, otherwise fire a missle if (touchMoved) { // If the touch was near the last [end] touch then we fire the thrusters, // otherwise, we fire a missile. NSLog(@"Thrusters...\n"); cpVect shipAngleVector = cpvforangle(shipBody->a); //cpVect shipAngleVector = cpv(cos(shipBody->a),sin(shipBody->a)); // Note that the magnitude of the thrust needs to be based on the mass of the object // being moved cpFloat thrustMagnitude = SHIP_MASS * THRUST_MULTIPLIER; cpBodyApplyImpulse(shipBody, cpvmult(shipAngleVector, thrustMagnitude), cpvzero); } else { // then fire a missle... NSLog(@"Missile...\n"); [[SimpleAudioEngine sharedEngine] playEffect:MISSILE_FIRED_WAV]; fireMissile(); }

8. CocosDenshion FAQ Q & A to some problems that you might bump into... I've got some wave files but they don't work, what can I do? http://www.cocos2d- iphone.org/wiki/doku.php/cocosdenshion:faq

9. Background music from ipod library You’ll need a provisioned device because the Simulator has no access to a device’s iPod library. Follow these instructions... http://developer.apple.com/iphone/library/docume ntation/Audio/Conceptual/iPodLibraryAccess_Gui de/Introduction/Introduction.html