Audio: Sound looping and stopping

GameLib/Audio.c

@@ -43,6 +43,8 @@ struct TAudioChan {
 	unsigned char rightvol;
 	unsigned char leftvol;
 
+	int loop;
+	
 	AudioChan next;
 };
 AudioChan _channels=NULL;
@@ -141,7 +143,11 @@ static void Audio_MixerCallback(void *ud,Uint8 *stream,int l){
 		if(chan_remain>len){
 			len_mix=len;
 		}else{
-			len_mix=chan_remain;
+			if(chan->loop){
+				len_mix=len;
+			}else{
+				len_mix=chan_remain;
+			}
 			chan->wave=NULL;
 		}
 
@@ -173,10 +179,21 @@ static void Audio_MixerCallback(void *ud,Uint8 *stream,int l){
 
 			// Next sample
 			ptr_out+=2;
-			ptr_wave++;
+			if(ptr_wave>=(((signed short *)wave->buffer)+(wave->len-1))){
+				ptr_wave=((signed short *)wave->buffer);
+			}else{
+				ptr_wave++;
+			}
 		}
 		chan->pos+=len_mix;
 
+		if(chan->wave==NULL && chan->loop==1){
+			chan->wave=wave;
+			while(chan->pos>wave->len){
+				chan->pos-=wave->len;
+			}
+		}
+		
 		// Next channel
 		prevchan=chan;
 		chan=chan->next;
@@ -303,13 +320,14 @@ AudioSnd Audio_LoadSound(char *filename){
 // Audio_PlaySound
 //
 // Loads a sound, giving a reference.
-void Audio_PlaySound(AudioSnd snd,
-	float leftvol, float rightvol)
+AudioChn Audio_PlaySound(AudioSnd snd,
+	float leftvol, float rightvol,int loop)
 {
 	AudioChan chan;
 	AudioWave wave;
-	if(!snd)
-		return;
+	if(!snd){
+		return(NULL);
+	}
 
 	// Cast AudioSnd to AudioWave
 	wave=snd;
@@ -329,7 +347,25 @@ void Audio_PlaySound(AudioSnd snd,
 	chan->pos=0;
 	chan->rightvol=(rightvol*255);
 	chan->leftvol=(leftvol*255);
+	chan->loop=loop;
+	
+	// Include in sounds list
 	chan->next=_channels;
 	_channels=chan;
+	
+	return chan;
 }
 
+
+/////////////////////////////
+// Audio_StopChan
+//
+// Stops an audio chanel
+void Audio_StopChan(AudioChn c){
+	AudioChan chan;
+	chan=c;
+	if(c==NULL){return;}
+	chan->loop=0;
+	chan->wave=NULL;
+}
+	

GameLib/Audio.h

@@ -25,6 +25,13 @@ void Audio_Frame();
 typedef void *AudioSnd;
 
 
+////////////////////////////////////////////////
+// AudioChn //
+//////////////
+// Reference to a playing sound.
+typedef void *AudioChn;
+
+
 /////////////////////////////
 // Audio_LoadSound
 //
@@ -36,8 +43,15 @@ AudioSnd Audio_LoadSound(char *filename);
 // Audio_PlaySound
 //
 // Loads a sound, giving a reference.
-void Audio_PlaySound(AudioSnd snd,
-	float leftvol, float rightvol);
+AudioChn Audio_PlaySound(AudioSnd snd,
+	float leftvol, float rightvol,int loop);
 
 
+/////////////////////////////
+// Audio_StopChan
+//
+// Stops an audio chanel
+void Audio_StopChan(AudioChn chan);
+	
+
 #endif

GameLib/GameLib.c

@@ -606,7 +606,17 @@ void GameLib_PlaySound(AudioSnd snd,int x,int y){
 	}
 
 	// PLAY!
-	Audio_PlaySound(snd,vleft,vright);
+	Audio_PlaySound(snd,vleft,vright,0);
+}
+
+
+/////////////////////////////
+// GameLib_PlayLoopingSound
+//
+//
+AudioChn GameLib_PlayLoopingSound(AudioSnd snd){
+	// PLAY!
+	return Audio_PlaySound(snd,1.0f,1.0f,1);
 }
 
 

GameLib/GameLib.h

@@ -108,6 +108,13 @@ int GameLib_EntityCustomCheckCollision(Entity ent,vec2 vel);
 void GameLib_PlaySound(AudioSnd snd,int x,int y);
 
 
+/////////////////////////////
+// GameLib_PlayLoopingSound
+//
+// Play a sound looping
+AudioChn GameLib_PlayLoopingSound(AudioSnd snd);
+
+
 /////////////////////////////
 // GameLib_EntitySetLight
 //