softvol, ao_pulse: prefer ao_pulse volume control by default

--softvol is enabled by default. For most audio outputs, this is a good
thing, as they have either their own (bad) soft volume implementation,
or control the system mixer. With ao_pulse, the situation is a bit
different: it supports per-application volume (i.e. volume control is
not really global). More importantly, ao_pulse uses a rather large audio
buffer, and changing the volume with mplayer's volume filter has a large
delay. With the native ao_pulse volume control, it's instant, because
PulseAudio's audio filtering happens at a later stage in its processing
pipeline (inaccessible for mplayer).

This means native volume control should really be allowed for ao_pulse,
while it's the reverse for other audio outputs. Make --softvol a choice
option, and add a new "auto" choice. This is default and will use PA's
volume control with ao_pulse, and mplayer's volume filter otherwise
(i.e. the old softvol behavior).

1 files changed, 7 insertions, 1 deletions

diff --git a/mixer.h b/mixer.h
index efeb62856f..3ba44ad0df 100644
--- a/mixer.h
+++ b/mixer.h
@@ -24,11 +24,17 @@
 #include "libaf/af.h"
 #include "libao2/audio_out.h"
 
+enum {
+    SOFTVOL_NO = 0,
+    SOFTVOL_YES = 1,
+    SOFTVOL_AUTO = 2,
+};
+
 typedef struct mixer {
     struct ao *ao;
     af_stream_t *afilter;
     int volstep;
-    bool softvol;
+    int softvol;
     float softvol_max;
     bool muted;
     bool muted_by_us;