X-Git-Url: http://git.cielonegro.org/gitweb.cgi?a=blobdiff_plain;f=Sound%2FEsounD%2FInternals.hs;h=60cf4b922b39d02aea0e26ab24e6b7047691ee75;hb=d4df6ebbadb94400304178fa4827e189462b57ec;hp=4f57a3b07e694772fc507bd2590041311411e73b;hpb=2c9350d4762d69bbfcdc58212e27506c3d4f7494;p=EsounD.git

diff --git a/Sound/EsounD/Internals.hs b/Sound/EsounD/Internals.hs
index 4f57a3b..60cf4b9 100644
--- a/Sound/EsounD/Internals.hs
+++ b/Sound/EsounD/Internals.hs
@@ -1,5 +1,7 @@
 {-# LANGUAGE
     EmptyDataDecls
+  , FlexibleInstances
+  , MultiParamTypeClasses
   , UnicodeSyntax
   #-}
 module Sound.EsounD.Internals
@@ -8,6 +10,10 @@ module Sound.EsounD.Internals
     , Channels(..)
     , Mono
     , Stereo
+    , interleave
+    , deinterleave
+
+    , toLSV
 
     , wrapSocket
     , closeSocket
@@ -16,6 +22,8 @@ module Sound.EsounD.Internals
     where
 import Bindings.EsounD
 import Data.Int
+import Data.StorableVector      as S
+import Data.StorableVector.Lazy as L
 import Foreign.C.String
 import Foreign.C.Types
 import Foreign.Ptr
@@ -36,14 +44,47 @@ instance Frame Int16 where
 class Channels ch where
     channelFmt ∷ ch → C'esd_format_t
 
+-- Mono
 data Mono
+
 instance Channels Mono where
     channelFmt _ = c'ESD_MONO
 
+-- Stereo
 data Stereo
+
 instance Channels Stereo where
     channelFmt _ = c'ESD_STEREO
 
+{-# INLINE interleave #-}
+interleave ∷ Storable α ⇒ L.Vector α → L.Vector α → L.Vector α
+interleave l r
+    -- THINKME: consider using storablevector-streamfusion
+    = let Just (lFr, l') = L.viewL l
+          Just (rFr, r') = L.viewL r
+          lr' = interleave l' r'
+      in
+        L.cons lFr (L.cons rFr lr')
+
+{-# INLINE deinterleave #-}
+deinterleave ∷ Storable α ⇒ L.Vector α → (L.Vector α, L.Vector α)
+deinterleave v
+    -- THINKME: consider using storablevector-streamfusion
+    = let (lr, v') = L.splitAt 2 v
+      in
+        if L.null lr then
+            (L.empty, L.empty)
+        else
+            let Just (lFr, r) = L.viewL lr
+                Just (rFr, _) = L.viewL r
+                (l', r') = deinterleave v'
+            in
+              (L.cons lFr l', L.cons rFr r')
+
+-- Utility functions
+toLSV ∷ Storable α ⇒ S.Vector α → L.Vector α
+toLSV v = L.fromChunks [v]
+
 wrapSocket ∷ String → CInt → IO Handle
 wrapSocket e (-1) = fail e
 wrapSocket _ fd   = fdToHandle (Fd fd)