Mercurial > sdl-ios-xcode
annotate src/cdrom/macosx/SDL_syscdrom_c.h @ 4241:d3a210342761 SDL-1.2
Fixed crash with right side up BMP files
author | Sam Lantinga <slouken@libsdl.org> |
---|---|
date | Sat, 26 Sep 2009 06:01:27 +0000 |
parents | a1b03ba2fcd0 |
children |
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 |
4159 | 3 Copyright (C) 1997-2009 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 */ |
1402
d910939febfa
Use consistent identifiers for the various platforms we support.
Sam Lantinga <slouken@libsdl.org>
parents:
1361
diff
changeset
|
22 #include "SDL_config.h" |
613
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
23 |
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
|
24 /* 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
|
25 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
|
26 */ |
613
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 /*********************************************************************************** |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
29 Implementation Notes |
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 |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
32 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
|
33 |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
34 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
|
35 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
|
36 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
|
37 |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
38 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
|
39 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
|
40 |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
41 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
|
42 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
|
43 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
|
44 |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
45 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
|
46 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
|
47 of SDL_CDStatus. |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
48 |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
49 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
|
50 |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
51 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
|
52 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
|
53 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
|
54 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
|
55 rescan for cdfs volumes. |
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 |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
59 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
|
60 |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
61 < Initializing > |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
62 |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
63 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
|
64 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
|
65 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
|
66 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
|
67 |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
68 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
|
69 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
|
70 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
|
71 |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
72 |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
73 < The Playback Loop > |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
74 |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
75 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
|
76 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
|
77 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
|
78 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
|
79 |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
80 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
|
81 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
|
82 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
|
83 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
|
84 GetFileForOffset() for this code. |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
85 |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
86 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
|
87 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
|
88 |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
89 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
|
90 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
|
91 indicates that we should. |
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 |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
94 < Magic > |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
95 |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
96 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
|
97 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
|
98 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
|
99 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
|
100 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
|
101 |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
102 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
|
103 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
|
104 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
|
105 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
|
106 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
|
107 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
|
108 |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
109 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
|
110 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
|
111 by us. |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
112 |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
113 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
|
114 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
|
115 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
|
116 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
|
117 to the sound card. |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
118 |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
119 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
|
120 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
|
121 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
|
122 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
|
123 |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
124 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
|
125 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
|
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 |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
130 #include "SDL_cdrom.h" |
1361
19418e4422cb
New configure-based build system. Still work in progress, but much improved
Sam Lantinga <slouken@libsdl.org>
parents:
769
diff
changeset
|
131 #include "../SDL_syscdrom.h" |
613
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
132 |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
133 #include "CDPlayer.h" |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
134 |
9c6717a1c66f
Added MacOS X CD-ROM audio support (thanks Max and Darrell)
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
|
135 #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
|
136 |