DirectMusic:
Looping Playback
By: Jack Hoxley
Written: June 2000
Download:
DM_Loop.Zip
(9kb)
Looping music is very important
for games; a piece of music may well last only 3 minutes, but they may well
be playing the same level for 2 hours. This tutorial will show you two ways
of looping; and it will also show you how to detect when the music is finished
playing - which can cue you to shuffle the music/play the next track.
Method 1: The easy way
This involves checking every second whether or not the segment is still playing.
If the SegmentState variables states that it is no longer playing you can start
it again. This is useful for games as you aren't checking quite so often, and
it really doesn't matter in a game how far through the piece you are. This method
will also show you whether or not it as finished - so you can shoose to loop
it or change the music track.
'This part goes in a timer,
or in the main game loop
'The smaller the interval the less-of a delay
'there is before it picks up on changes.
If seg Is Nothing Then Exit Sub
If perf.IsPlaying(seg, segstate) Then
lblPlay.Caption = "Is it still playing: Yes!"
Else
lblPlay.Caption = "Is it still playing: No!"
'At this point we decide:
'A. Loop the same piece
MsgBox "We've got to the end; now we start again"
Set segstate = perf.PlaySegment(seg, 0, 0)
'B. Play another piece
End If |
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Method 2: The Even Easier Way
There is a simple function call built into DirectMusic that you can use to set
loop points. You set two values, the start of the loop and the end of the loop
- if these are set to the beginning and the end then it'll loop the whole track.
'Where Segment is already
loaded, and is NOT playing.
Segment.SetLoopPoints 0, 0
'If they are both set to 0 then it will loop the entire
segment.
Segment.SetRepeats ??
'This will set it to repeat ?? many times - which
may well be useful to you. |
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Although these two methods could
be used to repeat any segment of a piece of music; they're easy to use for repeating
the whole segment.
You can download a working version
from the top of the page; or from the downloads page.
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