From: Fredrik Tolf <fredrik@dolda2000.com>
Date: Mon, 29 Sep 2008 20:34:38 +0000 (+0200)
Subject: Fixed audio playing
X-Git-Url: http://git.dolda2000.com/gitweb/?a=commitdiff_plain;p=kvidha.git

Fixed audio playing

SDL seems to have stopped being able to handle U8 PCM, so convert
Kvidha's sound buffer to S16 when filling.
---

diff --git a/sb.c b/sb.c
index 75293c8..7bc8484 100644
--- a/sb.c
+++ b/sb.c
@@ -12,11 +12,13 @@ void StartPlayBack(void)
     return;
 }
 
-static void SBCallback(void *uudata, unsigned char *Buffer, int Length)
+static void SBCallback(void *uudata, signed short *Buffer, int Length)
 {
+    int i;
     unsigned short Pos, Cur, Left;
     
     Pos = 0;
+    Length /= 2;
     while(Length > 0)
     {
 	if(SoundBufferPos >= (SB_SIZE >> 1))
@@ -26,7 +28,8 @@ static void SBCallback(void *uudata, unsigned char *Buffer, int Length)
 	}
 	Left = (SB_SIZE >> 1) - SoundBufferPos;
 	Cur = (Length > Left)?Left:Length;
-	memcpy(Buffer + Pos, SoundBuffer + SoundBufferPos, Cur);
+	for(i = 0; i < Cur; i++)
+	    Buffer[Pos + i] = (((signed char)SoundBuffer[SoundBufferPos + i]) - 128) * 255;
 	Pos += Cur;
 	SoundBufferPos += Cur;
 	Length -= Cur;
@@ -39,17 +42,17 @@ unsigned char SBReset(void)
     
     SoundBufferPos = SB_SIZE;
     my.freq = 44100;
-    my.format = AUDIO_U8;
+    my.format = AUDIO_S16;
     my.channels = 1;
     my.samples = SB_SIZE >> 1;
-    my.callback = SBCallback;
+    my.callback = (void (*)(void *, unsigned char *, int))SBCallback;
     if(SDL_OpenAudio(&my, &got) < 0)
     {
 	printf("Could not open SDL audio: %s\n", SDL_GetError());
 	return(1);
     }
     if((got.freq != 44100) ||
-       (got.format != AUDIO_U8) ||
+       (got.format != AUDIO_S16) ||
        (got.channels != 1))
     {
 	printf("Audio format mismatch(%i %i %i)!\n", got.freq, got.format, got.channels);