Inside Macintosh: Sound /

Chapter 2 - Sound Manager / Sound Manager Reference

Sound Manager Routines / Linking Modifiers to Sound Channels

SndAddModifier

The Sound Manager previously used the SndAddModifier function to link modifiers to sound channels.

FUNCTION SndAddModifier (chan: SndChannelPtr; modifier: ProcPtr; 
                         id: Integer; init: LongInt): OSErr;

chan

A pointer to a valid sound channel.

modifier

A pointer to a modifier function to be added to the sound channel specified by chan. This field is obsolete.

id

The resource ID of the modifier to be linked to the sound channel.

init

The initialization parameters for the sound channel specified by chan.

DESCRIPTION

The SndAddModifier function installs a modifier into an open channel specified in the chan parameter. The modifier parameter should be NIL, and the id parameter is the resource ID of the modifier to be linked to the sound channel. SndAddModifier causes the Sound Manager to load the specified 'snth' resource, lock it in memory, and link it to the channel specified.

IMPORTANT

The SndAddModifier function is for internal Sound Manager use only. You should not call it in your application.

The only supported use of the SndAddModifier function is to change the data type associated with a sound channel. For example, you can pass the constant sampledSynth in the id parameter to reconfigure a sound channel for sampled-sound data. You should, however, set a sound channel's data type when you call SndNewChannel, not by calling SndAddModifier.

SPECIAL CONSIDERATIONS

You should not use the SndAddModifier function.

RESULT CODES

noErr	0	No error
resProblem	-204	Problem loading the resource
badChannel	-205	Channel is corrupt or unusable

SEE ALSO

To modify sampled-sound data immediately before the Sound Manager plays it, you can customize double buffering routines so that your application can modify sampled-sound data when it fills a buffer of sound data for the Sound Manager to play. For more information, see "Using Double Buffers" on page 2-68.

To change the initialization options for a sound channel, you can use the reInitCmd command. For a description of that command, see "Sound Command Numbers" beginning on page 2-92.