/Classes/AudioSessionDemo.h

  1//
  2//  AudioSessionDemo.h
  3//  ObjectAL
  4//
  5//  Created by Karl Stenerud.
  6//
  7
  8#import "cocos2d.h"
  9#import "LampButton.h"
 10#import "ObjectAL.h"
 11
 12/**
 13 * This is mainly a test scene to try out various combinations of
 14 * audio session settings.
 15 *
 16 * Generally, you should set up the audio session settings ONCE, and then
 17 * use your program. Changing around settings after playing sounds or using
 18 * iPod playback can cause problems in certain situations, resulting in
 19 * no sound being output, error messages (especially in OpenAL), and even
 20 * crashes. You can try changing around live settings in this demo to see
 21 * what works and what doesn't, but there's no guarantee of consistency in
 22 * Apple's already obscure implementation.
 23 *
 24 *
 25 * The buttons are as follows:
 26 *
 27 * Session Active: Controls the audio session's state (active or not).
 28 * Once OpenAL initializes, you can't deactivate the session without first
 29 * disabling the current OpenAL context.
 30 *
 31 * Suspended: Controls suspending the sound system.  This works every time
 32 * because it first suspends OpenAL and AVAudioPlayer.
 33 * You need to suspend and resume for some of the audio session settings to
 34 * take effect.
 35 *
 36 * Allow iPod: When enabled, the application will use software decoding
 37 * (except in a special case where "Use Hardware" is enabled, see below).
 38 * This allows it to coexist with iPod music playing.
 39 *
 40 * iPod Ducking: When enabled, causes any iPod style music to decrease
 41 * in volume while the audio session is active.
 42 * Note: This only seems to work when "Silent Switch" is disabled.
 43 *
 44 * Silent Switch: Determines whether the app goes silent when the silent
 45 * switch is turned on.  Also prevents sound playback from stopping when
 46 * the screen locks.
 47 *
 48 * Use Hardware: When enabled, the sound system will attempt to use the
 49 * hardware decoder if available (no iPod music playing).  If the hardware
 50 * is not being used, the sound system will take it, preventing iPod playback.
 51 * If the hardware is being used, the sound system will use software decoding.
 52 * 
 53 * The "Play/Stop" and "Paused" buttons control looping OpenAL and AVAudioPlayer
 54 * playback.
 55 *
 56 *
 57 * BUGS:
 58 *
 59 * There are cases where iOS behaves weirdly, as can be demonstrated here.
 60 *
 61 * Case 1: iPod ducking fails to unduck.
 62 *
 63 * Steps to reproduce:
 64 * - iPod Ducking: ON
 65 * - Silent Switch: OFF
 66 * - Switch to iPod player and start playing.
 67 * - Suspending/unsuspending causes iPod to duck or unduck.
 68 * - Playing BOTH an ALSource and an AudioTrack, then suspending, will prevent
 69 *   iPod from unducking.
 70 *
 71 *
 72 * Case 2: iOS fails to clear interrupt.
 73 *
 74 * Steps to reproduce:
 75 * - Turn off "Allow iPod", "Silent Switch", and "iPod Ducking".
 76 * - Switch to the mini ipod player and start it playing. This causes an interrupt.
 77 * - Stop music in mini ipod player and return to the app. This does NOT clear the interrupt.
 78 * System is still interrupted and will not play sounds.
 79 * To clear the interrupt, background the app and then open it again.
 80 * OALAudioSupport has a method "forceEndInterruption" to help with these sorts of situations.
 81 */
 82@interface AudioSessionDemo : CCLayer
 83{
 84	ALSource* source;
 85	ALBuffer* buffer;
 86	OALAudioTrack* track;
 87	
 88	LampButton* allowIpodButton;
 89	LampButton* ipodDuckingButton;
 90	LampButton* honorSilentSwitchButton;
 91	LampButton* useHardwareButton;
 92	LampButton* sessionActiveButton;
 93	LampButton* suspendedButton;
 94	
 95	LampButton* playStopSource;
 96	LampButton* pauseSource;
 97	
 98	LampButton* playStopTrack;
 99	LampButton* pauseTrack;
100}
101
102@end