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annotate mixer/DESIGN @ 591:8faf61a640f0 tip

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Resynced fixes for unit conversion bugs in the Ogg Tremor decoder from SoundDecoder/ALmixer. Ogg Vorbis uses seconds and we multiply by 1000 to convert to milliseconds. But Ogg Tremor already uses milliseconds but I was still multiplying by 1000.
author Eric Wing <ewing . public |-at-| gmail . com>
date Thu, 25 Oct 2012 16:34:18 -0700
parents 859dd2ef3197
children
rev   line source
486
859dd2ef3197 Added some seriously INCOMPLETE mixer code.
Ryan C. Gordon <icculus@icculus.org>
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1 - Mixes internally in Float32. This simplifies the code immensely by only
859dd2ef3197 Added some seriously INCOMPLETE mixer code.
Ryan C. Gordon <icculus@icculus.org>
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2 having one format to screw with. It also makes life easy for end-user
859dd2ef3197 Added some seriously INCOMPLETE mixer code.
Ryan C. Gordon <icculus@icculus.org>
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3 callbacks. A native Float32 format should be added to SDL, too, so there
859dd2ef3197 Added some seriously INCOMPLETE mixer code.
Ryan C. Gordon <icculus@icculus.org>
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4 isn't unnecessary conversion if we can avoid it (i.e. - a CoreAudio backend).
859dd2ef3197 Added some seriously INCOMPLETE mixer code.
Ryan C. Gordon <icculus@icculus.org>
parents:
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5
859dd2ef3197 Added some seriously INCOMPLETE mixer code.
Ryan C. Gordon <icculus@icculus.org>
parents:
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6 - "Chunks" are just Sound_Samples...you can lock the mixer to screw with them
859dd2ef3197 Added some seriously INCOMPLETE mixer code.
Ryan C. Gordon <icculus@icculus.org>
parents:
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7 (i.e. - seeking in a playing Sample, etc). The mixer adds some opaque state
859dd2ef3197 Added some seriously INCOMPLETE mixer code.
Ryan C. Gordon <icculus@icculus.org>
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8 to Sound_Sample (current play position, how much is decoded, etc), some of
859dd2ef3197 Added some seriously INCOMPLETE mixer code.
Ryan C. Gordon <icculus@icculus.org>
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9 which can be queried and set.
859dd2ef3197 Added some seriously INCOMPLETE mixer code.
Ryan C. Gordon <icculus@icculus.org>
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10
859dd2ef3197 Added some seriously INCOMPLETE mixer code.
Ryan C. Gordon <icculus@icculus.org>
parents:
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11 - There is no "stopped" state. You are either in the playing list or you are
859dd2ef3197 Added some seriously INCOMPLETE mixer code.
Ryan C. Gordon <icculus@icculus.org>
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12 not, but state doesn't reset, so removing a sample from the list is more like
859dd2ef3197 Added some seriously INCOMPLETE mixer code.
Ryan C. Gordon <icculus@icculus.org>
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13 pausing it. If you put it back in the playing list without rewinding it, it
859dd2ef3197 Added some seriously INCOMPLETE mixer code.
Ryan C. Gordon <icculus@icculus.org>
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14 starts where it was.
859dd2ef3197 Added some seriously INCOMPLETE mixer code.
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15
859dd2ef3197 Added some seriously INCOMPLETE mixer code.
Ryan C. Gordon <icculus@icculus.org>
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16 - Fire and forget mixing is easy; flag a sample as "auto free" and it'll
859dd2ef3197 Added some seriously INCOMPLETE mixer code.
Ryan C. Gordon <icculus@icculus.org>
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17 delete itself when it's done playing. No need to set up a callback just to
859dd2ef3197 Added some seriously INCOMPLETE mixer code.
Ryan C. Gordon <icculus@icculus.org>
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18 clean up.
859dd2ef3197 Added some seriously INCOMPLETE mixer code.
Ryan C. Gordon <icculus@icculus.org>
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19
859dd2ef3197 Added some seriously INCOMPLETE mixer code.
Ryan C. Gordon <icculus@icculus.org>
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20 - No channels. You can mix as many samples as you have resources to
859dd2ef3197 Added some seriously INCOMPLETE mixer code.
Ryan C. Gordon <icculus@icculus.org>
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21 accomodate.
859dd2ef3197 Added some seriously INCOMPLETE mixer code.
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22
859dd2ef3197 Added some seriously INCOMPLETE mixer code.
Ryan C. Gordon <icculus@icculus.org>
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23 - No groups. This can be layered on top of the library if needed. If you
859dd2ef3197 Added some seriously INCOMPLETE mixer code.
Ryan C. Gordon <icculus@icculus.org>
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24 need atomic operations, lock the mixer.
859dd2ef3197 Added some seriously INCOMPLETE mixer code.
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25
859dd2ef3197 Added some seriously INCOMPLETE mixer code.
Ryan C. Gordon <icculus@icculus.org>
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26 - No music channel. Samples are samples. You can mix a MIDI as a sound effect
859dd2ef3197 Added some seriously INCOMPLETE mixer code.
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27 if you want, or a WAV file for background music. If you have the horsepower
859dd2ef3197 Added some seriously INCOMPLETE mixer code.
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28 to decode multiple compressed files at once, go for it.
859dd2ef3197 Added some seriously INCOMPLETE mixer code.
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29
859dd2ef3197 Added some seriously INCOMPLETE mixer code.
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30 - You can prebuffer/predecode as much of a sample as you like.
859dd2ef3197 Added some seriously INCOMPLETE mixer code.
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31
859dd2ef3197 Added some seriously INCOMPLETE mixer code.
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32 - Every sample mixes with a per-channel gain, plus a master gain that is
859dd2ef3197 Added some seriously INCOMPLETE mixer code.
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33 global to the mixer.
859dd2ef3197 Added some seriously INCOMPLETE mixer code.
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34
859dd2ef3197 Added some seriously INCOMPLETE mixer code.
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35 - Can handle non-power of two resampling.
859dd2ef3197 Added some seriously INCOMPLETE mixer code.
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36
859dd2ef3197 Added some seriously INCOMPLETE mixer code.
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37 - post mix hook, sample finished hook. Effects callback?
859dd2ef3197 Added some seriously INCOMPLETE mixer code.
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859dd2ef3197 Added some seriously INCOMPLETE mixer code.
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39
859dd2ef3197 Added some seriously INCOMPLETE mixer code.
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parents:
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40
859dd2ef3197 Added some seriously INCOMPLETE mixer code.
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41
859dd2ef3197 Added some seriously INCOMPLETE mixer code.
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42