added general fading (for fade-out)

it must be tested on MacOS and Linux.
a more general fading function would be better (with "fade to pause" and "fade to end").

git-svn-id: svn://svn.code.sf.net/p/ultrastardx/svn/branches/experimental@2672 b956fd51-792f-4845-bead-9b4dfca2ff2c

1 files changed, 7 insertions, 0 deletions

diff --git a/medley_new/src/media/UAudioPlayback_Bass.pas b/medley_new/src/media/UAudioPlayback_Bass.pas
index 1d7a44dc..8e1e5a9f 100644
--- a/medley_new/src/media/UAudioPlayback_Bass.pas
+++ b/medley_new/src/media/UAudioPlayback_Bass.pas
@@ -81,6 +81,7 @@ type
       procedure Pause();                    override;
       procedure Stop();                     override;
       procedure FadeIn(Time: real; TargetVolume: single); override;
+      procedure Fade(Time: real; TargetVolume: single); override;
 
       procedure AddSoundEffect(Effect: TSoundEffect);    override;
       procedure RemoveSoundEffect(Effect: TSoundEffect); override;
@@ -339,6 +340,12 @@ begin
   BASS_ChannelSlideAttribute(Handle, BASS_ATTRIB_VOL, TargetVolume, Trunc(Time * 1000));
 end;
 
+procedure TBassPlaybackStream.Fade(Time: real; TargetVolume: single);
+begin
+  // start fade-in: slide from fadeStart- to fadeEnd-volume in FadeTime
+  BASS_ChannelSlideAttribute(Handle, BASS_ATTRIB_VOL, TargetVolume, Trunc(Time * 1000));
+end;
+
 procedure TBassPlaybackStream.Pause();
 begin
   BASS_ChannelPause(Handle);