Added audio buffer mirroring, closes #53

glava.c

@@ -244,7 +244,7 @@ int main(int argc, char** argv) {
         .rate         = (unsigned int) r->rate_request,
         .format       = -1,
         .terminate    = 0,
-        .channels     = 2,
+        .channels     = r->mirror_input ? 1 : 2,
         .audio_out_r  = b0,
         .audio_out_l  = b1,
         .mutex        = PTHREAD_MUTEX_INITIALIZER,

glx_wcb.c

@@ -299,7 +299,7 @@ static void* create_and_bind(const char* name, const char* class,
             XFree(xvi);
         }
     }
-
+    
     if (best == -1) {
         fprintf(stderr, "Could not find suitable format for FBConfig\n");
         abort();

pulse_input.c

@@ -168,7 +168,11 @@ void* input_pulse(void* data) {
 
             int idx = (fsz - (ssz / 4)) + n;
 
-            if (audio->channels == 1) bl[idx] = (buf[i] + buf[i + 1]) / 2;
+            if (audio->channels == 1) {
+                float sample = (buf[i] + buf[i + 1]) / 2;
+                bl[idx] = sample;
+                br[idx] = sample;
+            }
 
             /* stereo storing channels in buffer */
             if (audio->channels == 2) {

render.c

@@ -685,6 +685,7 @@ struct renderer* rd_new(const char** paths, const char* entry,
     renderer* r = malloc(sizeof(struct renderer));
     *r = (struct renderer) {
         .alive                = true,
+        .mirror_input         = false,
         .gl                   = malloc(sizeof(struct gl_data)),
         .bufsize_request      = 8192,
         .rate_request         = 22000,
@@ -816,6 +817,10 @@ struct renderer* rd_new(const char** paths, const char* entry,
                     }
                 })
         },
+        {
+            .name = "setmirror", .fmt = "b",
+            .handler = RHANDLER(name, args, { r->mirror_input = *(bool*) args[0]; })
+        },
         {
             .name = "setbg", .fmt = "s",
             .handler = RHANDLER(name, args, {

render.h

@@ -5,7 +5,7 @@
 struct gl_data;
 
 typedef struct renderer {
-    bool    alive;
+    bool    alive, mirror_input;
     size_t  bufsize_request, rate_request, samplesize_request;
     char*   audio_source_request;
     struct gl_data* gl;

shaders/rc.glsl

@@ -41,6 +41,9 @@
    "none"   - Disable window opacity completely. */
 #request setopacity "native"
 
+/* Whether to mirror left and right audio input channels from PulseAudio.*/
+#request setmirror true
+
 /* OpenGL context and GLSL shader versions, do not change unless
    you *absolutely* know what you are doing. */
 #request setversion 3 3