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    NAME
        sound.datatype -- root data type for sounds.

    FUNCTION
        The sound.datatype is the super-class for any sound related
        classes.

    METHODS
        OM_NEW -- Create a new sound object.

        OM_GET -- Obtain the value of an attribute.

        OM_SET -- Set the values of multiple attributes.

        OM_UPDATE -- Update the values of multiple attributes.

        OM_DISPOSE -- Dispose of a sound object.

        GM_LAYOUT -- Layout the object and notify the application of the
            title and size.

        GM_HITTEST -- Determine if the object has been hit with the
            mouse.

        GM_GOACTIVE -- Tell the object to go active.  On SELECTDOWN, the
            sound will start playing.

        GM_HANDLEINPUT -- Handle input.  Currently input (other than
            SELECTDOWN) doesn't affect the sound.

        GM_RENDER -- cause the graphic to render.  currently the graphic
            for the sound is just a static icon.

        DTM_TRIGGER -- cause an event to occur.  currently the only
            trigger event is STM_PLAY, which will cause the sound to start
            playing.

            NOTE: Subclasses which support streaming data access may
                  support more than just the STM_PLAY event.

        DTM_COPY -- Copy the entire sound to the clipboard as 8SVX.

            NOTE: Up to and including V40 sound.datatype never stored
                  a valid voiceheader with the file. this was fixed in v44.

                  Subclasses which support streaming data access may not
                  support this method.

        DTM_WRITE -- write the entire sound to a file as 8svx.

            NOTE: Up to and including V40 sound.datatype never stored
                  a valid voiceheader with the file. this was fixed in v44.

                  Subclasses which support streaming data access may not
                  support this method.

    TAGS
        SDTA_VoiceHeader (struct voiceheader *) -- set and get the base
            information for the sound.  voiceheader is defined in
            <datatypes/soundclass.h>.

            NOTE: Up to and including V40 sound.datatype never returned
                  a valid voiceheader for om_get and the voiceheader data
                  was ignored in the OM_NEW/OM_SET cases. This was fixed
                  in V44.

            Applicability is (ISG).

        SDTA_Sample (BYTE *) -- Set and get the sound data.  Starting
            with V40 the sample data does not need to be in CHIP memory.
            Starting with V44 the sample data does not need to start
            on a WORD-aligned address. Setting SDTA_Sample to NULL
            will stop sound replay if sound.datatype was started
            playing with a non-NULL SDTA_Sample parameter.

            The SDTA_Sample parameter selects mono playback on any
            sound channel that is currently available.

            NOTE: For streaming sound playback, SDTA_LeftSample,
                  SDTA_RightSample, and SDTA_Sample will all be
                  NULL (V44).

            Applicability is (ISG).

        SDTA_SampleLength (ULONG) -- Length of the sound data in bytes.
            Starting with V44 the sample data does not need to be
            an even number of bytes. Setting SDTA_SampleLength to 0
            will stop sound replay.

            Applicability is (ISG).

        SDTA_Period (UWORD) -- Set and get the period of the sound
            (in timing intervals per sample). This attribute can be
            used to affect a playing sound. Please note that the
            Amiga audio hardware does not reliably support playback
            periods shorter than 124; sound.datatype will limit the
            period to valid intervals (V44).

            Default for this tag is 394.  Applicability is (ISG).

        SDTA_Volume (UWORD) -- Set and get the volume of the sound. This
            attribute can be used to affect a playing sound.

            Valid range is from 0 to 64.  Default for this tag is 64.
            Applicability is (ISG).

        SDTA_Cycles (UWORD) -- Set and get the number of cycles the
            sound will be played.

            Default for this tag is 1.  Applicability is (ISG).

        The following tags are new for V40.

        SDTA_SignalTask (struct task *) -- task to signal when the
            is complete, or if SDTA_Continuous is TRUE, when
            the next buffer is needed.

            Default for this tag is NULL. Applicability is (IS).

        SDTA_SignalBit (ULONG) -- signal mask to use with sdta_signaltask
            or 0 to disable.

            NOTE: Due to a bug in sound.datatype V40 SDTA_SignalBit was
                  actually implemented as a signal mask as opposed to a
                  bit number. The documentation now reflects this. If you
                  intend to use a signal bit number instead of the mask,
                  use the new V44 tag SDTA_SignalBitNumber below.

            Default for this tag is 0. Applicability is (IS).

        SDTA_Continuous (BOOL) -- Used to indicate that the sound
            datatype will be fed a continuous stream of data.

            Default for this tag is FALSE. Applicability is (I).

        The following tags are new for V44.

        SDTA_SignalBitMask (ULONG) -- signal mask to use with sdta_signaltask
            or 0 to disable. This tag is an alias for SDTA_SignalBit.

            Default for this tag is 0. Applicability is (IS).

        SDTA_SignalBitNumber (BYTE) -- signal bit to use with sdta_signaltask
            or -1 to disable.

            Default for this tag is -1. Applicability is (IS).

        SDTA_SamplesPerSec (UWORD) -- Set and get the replay frequency of
            a sound (in Hz). This attribute can be used to affect a playing
            sound. Unlike the SDTA_Period tag, which serves the same purpose,
            this tag automatically takes the system clock value into account.
            Please note that the Amiga audio hardware does not reliably
            support playback rates beyond 28,000 samples per second;
            sound.datatype will limit the replay frequency to valid
            intervals.

            Applicability is (ISG).

        SDTA_ReplayPeriod (struct timeval *) -- get the replay period,
            i.e. the time it takes for the complete sound to be played.
            If the sample size has not been set yet, the timeval tv_sec
            and tv_micro members will be set to 0. If the sample is to
            be played continuously, both timeval members will be set
            to 0xFFFFFFFF.

            Applicability is (G).

        SDTA_Pan (BYTE) -- Set the stereo panning; this must be set to
            a number in the range of -64..64. A value of -64 will
            pan the sound to the left channel, silencing the right
            channel; a value of 64 will pan the sound to the right
            channel and silence the left channel. To center playback,
            use a panning value of 0. The panning value only takes
            effect if a stereo sound is being played.

            Default for this tag is 0. Applicability is (IS).

        SDTA_FreeSampleData (BOOL) -- This tag controls whether
            sound.datatype will call freevec() on the sample data
            attached to an object. If the SDTA_Continuous attribute was
            set to TRUE, sound.datatype will never free any data attached
            to an object. It is safe to attach the same sample to
            more than one channel as sound.datatype will make sure that
            no sample data is freed twice.

            Default for this tag is FALSE. Applicability is (IS).

        SDTA_LeftSample (BYTE *) -- Set and get the left channel sound data.
            The sample data does not need to be in CHIP memory and does
            not need to start on a WORD-aligned address. Setting
            SDTA_LeftSample to NULL will stop sound replay if sound.datatype
            was started playing with a non-NULL SDTA_LeftSample parameter.

            The SDTA_LeftSample parameter alone selects mono playback on
            any left sound channel that is currently available. Used together
            with the SDTA_RightSample parameter, stereo playback on any
            available stereo channels is selected.

            The SDTA_LeftSample parameter takes precedence over the
            the SDTA_Sample parameter.

            NOTE: For streaming sound playback, SDTA_LeftSample,
                  SDTA_RightSample, and SDTA_Sample will all be
                  NULL (V44).

            Applicability is (ISG).

        SDTA_RightSample (BYTE *) -- Set and get the right channel sound data
.
            The sample data does not need to be in CHIP memory and does
            not need to start on a WORD-aligned address. Setting
            SDTA_RightSample to NULL will stop sound replay if sound.datatype
            was started playing with a non-NULL SDTA_RightSample parameter.

            The SDTA_RightSample parameter alone selects mono playback on
            any right sound channel that is currently available. Used
            together with the SDTA_LeftSample parameter, stereo playback
            on any available stereo channels is selected.

            The SDTA_RightSample parameter takes precedence over the
            the SDTA_Sample parameter.

            NOTE: For streaming sound playback, SDTA_LeftSample,
                  SDTA_RightSample, and SDTA_Sample will all be
                  NULL (V44).

            Applicability is (ISG).

        SDTA_SyncSampleChange (BOOL) -- If SDTA_Continuous was set to TRUE,
            sound.datatype will expect a continuous stream of data to be
            played. By specifying "SDTA_SyncSampleChange,TRUE" you request
            that new sound data will be played only if the old data has
            been played completely (otherwise, playback would restart
            immediately with the new sound). If playback is currently in
            progress, the task to change the sample data will be made to
            wait until playback of the old sound has finished.

            Default for this tag is FALSE. Applicability is (IS).

        DTA_Immediate (BOOL) -- Select and query whether playback should
            start immediately after the object has passed the layout
            process.

            Default for this tag is FALSE. Applicability is (ISG).

        DTA_Repeat (BOOL) -- Select and query whether playback should
            loop indefinitely, regardless of the current SDTA_Cycles
            settings.

            Default for this tag is FALSE. Applicability is (ISG).

    NOTES
        You cannot switch between mono and stereo playback on the fly while
        the sound is still playing. First, stop the sound, then change the
        SDTA_Sample/SDTA_LeftSample/SDTA_LeftSample attributes.

        The sound.datatype implementation has been cleaned up for V44 to
        allow for streaming subclasses to be written. Such subclasses will
        always return NULL when their SDTA_LeftSample, SDTA_RightSample and
        SDTA_Sample attributes are queried. However, they will never return
        0 for the SDTA_SampleLength and SDTA_SamplesPerSec attributes since
        these can be used to calculate the length of the entire sample.
        Streaming subclasses will respond to the DTM_TRIGGER method, to
        start, stop playback, etc. but may not support any other methods
        which rely upon the entire sample to reside in memory.