ncmixer

commit 9fb4e2701289919ff9e947c5bab0b23b5623ddb7
parent 0d5b55aa3dba8236043d41e8692b684af56e32ed
Author: sin <sin@2f30.org>
Date:   Fri,  3 Jun 2016 18:21:40 +0100

Add primitive mixing support

Diffstat:
M
Makefile
 | 
2
+-
M
ncmixer.c
 | 
22
+++++++++++++++++++---

2 files changed, 20 insertions(+), 4 deletions(-)
diff --git a/Makefile b/Makefile
@@ -1,6 +1,6 @@
 CPPFLAGS = -DDEBUG
 CFLAGS = -Wall
-LDLIBS = -lsndio -lcurses
+LDLIBS = -lsndio -lcurses -lm
 OBJ = ncmixer.o
 BIN = ncmixer
 
diff --git a/ncmixer.c b/ncmixer.c
@@ -56,6 +56,7 @@ struct input {
 	int listenfd;
 	int clifd;
 	short buf[NSAMPLES];
+	short attenuated_buf[NSAMPLES];
 	int nsamples;
 	int active;
 	int monitor;
@@ -249,15 +250,23 @@ consume(struct input *in)
 }
 
 void
-attenuate(void)
+attenuate(struct input *in, float factor)
 {
+	short *ch0 = (short *)in->buf;
+	short *out = (short *)in->attenuated_buf;
+	int i;
+
+	for (i = 0; i < in->nsamples; i++) {
+		*out = *ch0 * factor;
+		ch0++, out++;
+	}
 }
 
 int
 mix(struct input *in1, struct input *in2, struct output *out)
 {
-	short *ch0 = (short *)in1->buf;
-	short *ch1 = (short *)in2->buf;
+	short *ch0 = (short *)in1->attenuated_buf;
+	short *ch1 = (short *)in2->attenuated_buf;
 	short *buf = (short *)out->buf;
 	int i;
 
@@ -403,6 +412,13 @@ loop(void)
 				if (out->sio_hdl == NULL)
 					continue;
 			}
+			if (xfpos <= 0) {
+				attenuate(&inputs[0], 1.0);
+				attenuate(&inputs[1], 1.0 - abs(xfpos));
+			} else {
+				attenuate(&inputs[0], 1.0 - abs(xfpos));
+				attenuate(&inputs[1], 1.0);
+			}
 			mix(&inputs[0], &inputs[1], out);
 			ret = audio_play(out->sio_hdl, out->buf,
 			                 out->nsamples * 2);