Mercurial > sdl-ios-xcode
annotate src/cdrom/macosx/SDL_syscdrom_c.h @ 1250:a4d515d0fc3a
Fixed up build script to catch some of the newer files in a "make dist" run.
author | Ryan C. Gordon <icculus@icculus.org> |
---|---|
date | Thu, 19 Jan 2006 08:36:41 +0000 |
parents | b8d311d90021 |
children | 19418e4422cb |
rev | line source |
---|---|
613
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
1 /* |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
2 SDL - Simple DirectMedia Layer |
769
b8d311d90021
Updated copyright information for 2004 (Happy New Year!)
Sam Lantinga <slouken@libsdl.org>
parents:
768
diff
changeset
|
3 Copyright (C) 1997-2004 Sam Lantinga |
613
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
4 |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
5 This library is free software; you can redistribute it and/or |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
6 modify it under the terms of the GNU Library General Public |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
7 License as published by the Free Software Foundation; either |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
8 version 2 of the License, or (at your option) any later version. |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
9 |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
10 This library is distributed in the hope that it will be useful, |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
11 but WITHOUT ANY WARRANTY; without even the implied warranty of |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
13 Library General Public License for more details. |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
14 |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
15 You should have received a copy of the GNU Library General Public |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
16 License along with this library; if not, write to the Free |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
17 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
18 |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
19 Sam Lantinga |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
20 slouken@libsdl.org |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
21 */ |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
22 |
768
de1b2c3063b9
Max has been reworking this code so it works on MacOS X 10.1
Sam Lantinga <slouken@libsdl.org>
parents:
613
diff
changeset
|
23 /* This is the Mac OS X / CoreAudio specific header for the SDL CD-ROM API |
de1b2c3063b9
Max has been reworking this code so it works on MacOS X 10.1
Sam Lantinga <slouken@libsdl.org>
parents:
613
diff
changeset
|
24 Contributed by Darrell Walisser and Max Horn |
de1b2c3063b9
Max has been reworking this code so it works on MacOS X 10.1
Sam Lantinga <slouken@libsdl.org>
parents:
613
diff
changeset
|
25 */ |
613
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
26 |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
27 /*********************************************************************************** |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
28 Implementation Notes |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
29 ********************* |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
30 |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
31 This code has several limitations currently (all of which are proabaly fixable): |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
32 |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
33 1. A CD-ROM device is inferred from a mounted cdfs volume, so device 0 is |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
34 not necessarily the first CD-ROM device on the system. (Somewhat easy to fix |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
35 by useing the device name from the volume id's to reorder the volumes) |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
36 |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
37 2. You can only open and control 1 CD-ROM device at a time. (Challenging to fix, |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
38 due to extensive code restructuring) |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
39 |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
40 3. The status reported by SDL_CDStatus only changes to from CD_PLAYING to CD_STOPPED in |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
41 1-second intervals (because the audio is buffered in 1-second chunks) If |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
42 the audio data is less than 1 second, the remainder is filled with silence. |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
43 |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
44 If you need to play sequences back-to-back that are less that 1 second long, |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
45 use the frame position to determine when to play the next sequence, instead |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
46 of SDL_CDStatus. |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
47 |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
48 This may be possible to fix with a clever usage of the AudioUnit API. |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
49 |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
50 4. When new volumes are inserted, our volume information is not updated. The only way |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
51 to refresh this information is to reinit the CD-ROM subsystem of SDL. To fix this, |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
52 one would probably have to fix point 1 above first, then figure out how to register |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
53 for a notification when new media is mounted in order to perform an automatic |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
54 rescan for cdfs volumes. |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
55 |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
56 |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
57 |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
58 So, here comes a description of how this all works. |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
59 |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
60 < Initializing > |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
61 |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
62 To get things rolling, we have to locate mounted volumes that contain |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
63 audio (since nearly all Macs don't have analog audio-in on the sound card). |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
64 That's easy, since these volumes have a flag that indicates this special |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
65 filesystem. See DetectAudioCDVolumes() in CDPlayer.cpp for this code. |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
66 |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
67 Next, we parse the invisible .TOC.plist in the root of the volume, which gets us |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
68 the track information (number, offset, length, leadout, etc). See ReadTOCData() in |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
69 CDPlayer.cpp for the skinny on this. |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
70 |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
71 |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
72 < The Playback Loop > |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
73 |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
74 Now come the tricky parts. Let's start with basic audio playback. When a frame |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
75 range to play is requested, we must first find the .aiff files on the volume, |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
76 hopefully in the right order. Since these files all begin with a number "1 Audio Track", |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
77 etc, this is used to determine the correct track order. |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
78 |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
79 Once all files are determined, we have to find what file corresponds to the start |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
80 and length parameter to SDL_SYS_CDPlay(). Again, this is quite simple by walking the |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
81 cdrom's track list. At this point, we also save the offset to the next track and frames |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
82 remaining, if we're going to have to play another file after the first one. See |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
83 GetFileForOffset() for this code. |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
84 |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
85 At this point we have all info needed to start playback, so we hand off to the LoadFile() |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
86 function, which proceeds to do its magic and plays back the file. |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
87 |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
88 When the file is finished playing, CompletionProc() is invoked, at which time we can |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
89 play the next file if the previously saved next track and frames remaining |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
90 indicates that we should. |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
91 |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
92 |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
93 < Magic > |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
94 |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
95 OK, so it's not really magic, but since I don't fully understand all the hidden details it |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
96 seems like it to me ;-) The API's involved are the AudioUnit and AudioFile API's. These |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
97 appear to be an extension of CoreAudio for creating modular playback and f/x entities. |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
98 The important thing is that CPU usage is very low and reliability is very high. You'd |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
99 be hard-pressed to find a way to stutter the playback with other CPU-intensive tasks. |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
100 |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
101 One part of this magic is that it uses multiple threads, which carries the usual potential |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
102 for disaster if not handled carefully. Playback currently requires 4 additional threads: |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
103 1. The coreaudio runloop thread |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
104 2. The coreaudio device i/o thread |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
105 3. The file streaming thread |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
106 4. The notification/callback thread |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
107 |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
108 The first 2 threads are necessary evil - CoreAudio creates this no matter what the situation |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
109 is (even the SDL sound implementation creates theses suckers). The last two are are created |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
110 by us. |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
111 |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
112 The file is streamed from disk using a threaded double-buffer approach. |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
113 This way, the high latency operation of reading from disk can be performed without interrupting |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
114 the real-time device thread (which amounts to avoiding dropouts). The device thread grabs the |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
115 buffer that isn't being read and sends it to the CoreAudio mixer where it eventually gets |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
116 to the sound card. |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
117 |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
118 The device thread posts a notification when the file streaming thread is out of data. This |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
119 notification must be handled in a separate thread to avoid potential deadlock in the |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
120 device thread. That's where the notification thread comes in. This thread is signaled |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
121 whenever a notification needs to be processed, so another file can be played back if need be. |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
122 |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
123 The API in CDPlayer.cpp contains synchronization because otherwise both the notification thread |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
124 and main thread (or another other thread using the SDL CD api) can potentially call it at the same time. |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
125 |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
126 ************************************************************************************/ |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
127 |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
128 |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
129 #include "SDL_cdrom.h" |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
130 #include "SDL_syscdrom.h" |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
131 |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
132 #include "CDPlayer.h" |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
133 |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
134 #define kErrorFakeDevice "Error: Cannot proceed since we're faking a CD-ROM device. Reinit the CD-ROM subsystem to scan for new volumes." |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
135 |