SoundCtrl_ExamineMixer (changes)
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SoundControl
» SWI Calls
» SoundCtrl_ExamineMixer
SoundCtrl_ExamineMixer
(SWI &50000)
| Entry | |
|---|---|
| R0 | Mixer system |
| R1 | Pointer to word-aligned buffer for result |
| R2 | Buffer size (may be 0) |
| Exit | |
|---|---|
| R1 | Buffer filled with as many blocks as possible |
| R2 | Decremented by number of bytes needed for complete description |
| R3 | Individual block size (bytes) – will be a multiple of 4 |
| R4 | Number of blocks placed in buffer |
Use
This SWI is used to read the features of a given mixer.
If R2 is negative on exit, then the supplied buffer was too small to contain the full description and should be resized.
Notes
R0 can either be a pointer to a null/control-terminated audio controller device ID string (as returned bySound_EnumerateDevices?Sound_EnumerateControllers or 0 (NULL ) to refer to the mixer for the current default audio controller. device.
Other SoundControl APIs such as SoundCtrl_SetMix use category and index parameters to identify each mixer channel, but the blocks that are placed within the buffer only indicate the category. The index of a given channel can be determined by looking at how many channels with the same category occur before it; for any given category, the first block in the buffer with that category is index 0, the second block with that category is index 1, etc.
See also
- SoundCtrl_GetMix
- SoundCtrl_SetMix
Sound_EnumerateDevices?Sound_EnumerateControllers
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