VBAP backend re-work (part one):

* fix azimuth, don't clamp but map to [0,1]
* prepare elevation (10+ speakers)

diff --git a/libs/panners/vbap/vbap.cc b/libs/panners/vbap/vbap.cc
index 0de8d3a29af5c95c8ba7c11f4950ac4519ba9da9..454d04f7f4ae4ebcd17a1292ce04236acc7eda43 100644 (file)
--- a/libs/panners/vbap/vbap.cc
+++ b/libs/panners/vbap/vbap.cc
@@ -118,7 +118,12 @@ VBAPanner::configure_io (ChanCount in, ChanCount /* ignored - we use Speakers */
 void
 VBAPanner::update ()
 {
-        /* recompute signal directions based on panner azimuth and, if relevant, width (diffusion) and elevation parameters */
+        /* recompute signal directions based on panner azimuth and, if relevant, width (diffusion) parameters)
+         */
+
+        /* panner azimuth control is [0 .. 1.0] which we interpret as [0 .. 360] degrees
+         */
+        double center = _pannable->pan_azimuth_control->get_value() * 360.0;
         double elevation = _pannable->pan_elevation_control->get_value() * 90.0;
 
         if (_signals.size() > 1) {
@@ -127,15 +132,45 @@ VBAPanner::update ()
                 double grd_step_per_signal = w / (_signals.size() - 1);
                 for (vector<Signal*>::iterator s = _signals.begin(); s != _signals.end(); ++s) {
                 
-                        Signal* signal = *s;
+                double max_dir = center + (w/2.0);
+                if (max_dir > 360.0) {
+                        max_dir = max_dir - 360.0;
+                }
+                max_dir = max (min (max_dir, 360.0), 0.0);
+                
+                if (max_dir < min_dir) {
+                        swap (max_dir, min_dir);
+                }
+
+                double degree_step_per_signal = (max_dir - min_dir) / (_signals.size() - 1);
+                double signal_direction = min_dir;
+
+                if (w >= 0.0) {
+
+                        /* positive width - normal order of signal spread */
+
+                        for (vector<Signal*>::iterator s = _signals.begin(); s != _signals.end(); ++s) {
+                        
+                                Signal* signal = *s;
+
+                                signal->direction = AngularVector (signal_direction, elevation);
+                                compute_gains (signal->desired_gains, signal->desired_outputs, signal->direction.azi, signal->direction.ele);
+                                signal_direction += degree_step_per_signal;
+                        }
+                } else {
 
                         int over = signal_direction;
                         over -= (signal_direction >= 0) ? 0 : 1;
                         signal_direction -= (double)over;
 
-                        signal->direction = AngularVector (signal_direction * 360.0, elevation);
-                        compute_gains (signal->desired_gains, signal->desired_outputs, signal->direction.azi, signal->direction.ele);
-                        signal_direction += grd_step_per_signal;
+                        for (vector<Signal*>::reverse_iterator s = _signals.rbegin(); s != _signals.rend(); ++s) {
+                        
+                                Signal* signal = *s;
+
+                                signal->direction = AngularVector (signal_direction, elevation);
+                                compute_gains (signal->desired_gains, signal->desired_outputs, signal->direction.azi, signal->direction.ele);
+                                signal_direction += degree_step_per_signal;
+                        }
                 }
         } else if (_signals.size() == 1) {
                 double center = _pannable->pan_azimuth_control->get_value() * 360.0;
@@ -477,11 +512,7 @@ void
 VBAPanner::reset ()
 {
        set_position (0);
-        if (_signals.size() > 1) {
-                set_width (1.0 - (1.0 / (double)_signals.size()));
-        } else {
-                set_width (0);
-        }
+       set_width (1);
        set_elevation (0);
 
        update ();