VBAP rework (part III): fix position computation backend & GUI

3 files changed, 71 insertions, 87 deletions

diff --git a/gtk2_ardour/panner2d.cc b/gtk2_ardour/panner2d.cc
index b11e05e0d4..59e70acd03 100644
--- a/gtk2_ardour/panner2d.cc
+++ b/gtk2_ardour/panner2d.cc
@@ -82,7 +82,7 @@ Panner2d::Panner2d (boost::shared_ptr<PannerShell> p, int32_t h)
 	drag_target = 0;
 	set_events (Gdk::BUTTON_PRESS_MASK|Gdk::BUTTON_RELEASE_MASK|Gdk::POINTER_MOTION_MASK);
 
-        handle_position_change ();
+	handle_position_change ();
 }
 
 Panner2d::~Panner2d()
@@ -206,7 +206,6 @@ Panner2d::handle_state_change ()
 void
 Panner2d::label_signals ()
 {
-        double w = panner_shell->pannable()->pan_width_control->get_value();
         uint32_t sz = signals.size();
 
 	switch (sz) {
@@ -218,23 +217,14 @@ Panner2d::label_signals ()
 		break;
 
 	case 2:
-                if (w  >= 0.0) {
-                        signals[0]->set_text ("R");
-                        signals[1]->set_text ("L");
-                } else {
-                        signals[0]->set_text ("L");
-                        signals[1]->set_text ("R");
-                }
+                signals[0]->set_text ("L");
+                signals[1]->set_text ("R");
 		break;
 
 	default:
 		for (uint32_t i = 0; i < sz; ++i) {
 			char buf[64];
-                        if (w >= 0.0) {
-                                snprintf (buf, sizeof (buf), "%" PRIu32, i + 1);
-                        } else {
-                                snprintf (buf, sizeof (buf), "%" PRIu32, sz - i);
-                        }
+                        snprintf (buf, sizeof (buf), "%" PRIu32, i + 1);
 			signals[i]->set_text (buf);
 		}
 		break;
@@ -247,7 +237,8 @@ Panner2d::handle_position_change ()
 	uint32_t n;
         double w = panner_shell->pannable()->pan_width_control->get_value();
 
-        position.position = AngularVector (panner_shell->pannable()->pan_azimuth_control->get_value() * 360.0, 0.0);
+        position.position = AngularVector (panner_shell->pannable()->pan_azimuth_control->get_value() * 360.0,
+                                           panner_shell->pannable()->pan_elevation_control->get_value() * 90.0);
 
         for (uint32_t i = 0; i < signals.size(); ++i) {
                 signals[i]->position = panner_shell->panner()->signal_position (i);
@@ -693,22 +684,39 @@ Panner2d::handle_motion (gint evx, gint evy, GdkModifierType state)
 		}
 
 		if (need_move) {
-			CartesianVector cp (evx, evy, 0.0);
-                        AngularVector av;
-
-			/* canonicalize position and then clamp to the circle */
+			set<Evoral::Parameter> params = panner_shell->panner()->what_can_be_automated();
+			set<Evoral::Parameter>::iterator p = params.find(PanElevationAutomation);
 
+			double y0 = 4.0;
+			if (height > large_size_threshold) {
+				y0 = 12.0;
+			}
+			CartesianVector cp (evx - 12.0, evy - y0, 0.0);
+			AngularVector av;
 			gtk_to_cart (cp);
-			clamp_to_circle (cp.x, cp.y);
-
-			/* generate an angular representation of the current mouse position */
-
-			cp.angular (av);
 
-                        if (drag_target == &position) {
-                                double degree_fract = av.azi / 360.0;
-                                panner_shell->panner()->set_position (degree_fract);
-                        }
+			if (p == params.end()) {
+				clamp_to_circle (cp.x, cp.y);
+				cp.angular (av);
+				if (drag_target == &position) {
+					double degree_fract = av.azi / 360.0;
+					panner_shell->panner()->set_position (degree_fract);
+				}
+			} else {
+				/* sphere projection */
+				sphere_project (cp.x, cp.y, cp.z);
+
+				double r2d = 180.0 / M_PI;
+				av.azi = r2d * atan2(cp.y, cp.x);
+				av.ele = r2d * asin(cp.z);
+
+				if (drag_target == &position) {
+					double azi_fract = av.azi / 360.0;
+					double ele_fract = av.ele / 90.0;
+					panner_shell->panner()->set_position (azi_fract);
+					panner_shell->panner()->set_elevation (ele_fract);
+				}
+			}
 		}
 	}
 
@@ -762,12 +770,26 @@ Panner2d::gtk_to_cart (CartesianVector& c) const
 }
 
 void
+Panner2d::sphere_project (double& x, double& y, double& z)
+{
+	double r, r2;
+	r2 = x * x + y * y;
+	if (r2 < 1.0) {
+		z = sqrt (1.0 - r2);
+	} else {
+		r = sqrt (r2);
+		x = x / r;
+		y = y / r;
+		z = 0.0;
+	}
+}
+
+void
 Panner2d::clamp_to_circle (double& x, double& y)
 {
 	double azi, ele;
 	double z = 0.0;
-        double l;
-
+	double l;
 	PBD::cartesian_to_spherical (x, y, z, azi, ele, l);
 	PBD::spherical_to_cartesian (azi, ele, 1.0, x, y, z);
 }
diff --git a/gtk2_ardour/panner2d.h b/gtk2_ardour/panner2d.h
index 474d7e1b10..9df0355518 100644
--- a/gtk2_ardour/panner2d.h
+++ b/gtk2_ardour/panner2d.h
@@ -142,6 +142,7 @@ class Panner2d : public Gtk::DrawingArea
 	   and centered in the middle of our area
 	*/
 	void clamp_to_circle (double& x, double& y);
+	void sphere_project (double& x, double& y, double& z);
 };
 
 class Panner2dWindow : public ArdourWindow
diff --git a/libs/panners/vbap/vbap.cc b/libs/panners/vbap/vbap.cc
index a56a5a720d..d0202d4466 100644
--- a/libs/panners/vbap/vbap.cc
+++ b/libs/panners/vbap/vbap.cc
@@ -114,70 +114,27 @@ 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) 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;
+        /* recompute signal directions based on panner azimuth and, if relevant, width (diffusion) and elevation parameters */
         double elevation = _pannable->pan_elevation_control->get_value() * 90.0;
 
         if (_signals.size() > 1) {
-
-                /* panner width control is [-1.0 .. 1.0]; we ignore sign, and map to [0 .. 360] degrees
-                   so that a width of 1 corresponds to a signal equally present from all directions, 
-                   and a width of zero corresponds to a point source from the "center" (above) point
-                   on the perimeter of the speaker array.
-                */
-
-                double w = fabs (_pannable->pan_width_control->get_value()) * 360.0;
+                double w = (_pannable->pan_width_control->get_value());
+                double signal_direction = _pannable->pan_azimuth_control->get_value() - (w/2);
+                double grd_step_per_signal = w / (_signals.size() - 1);
+                for (vector<Signal*>::iterator s = _signals.begin(); s != _signals.end(); ++s) {
                 
-                double min_dir = center - (w/2.0);
-                if (min_dir < 0) {
-                        min_dir = 360.0 + min_dir; // its already negative
-                }
-                min_dir = max (min (min_dir, 360.0), 0.0);
-                
-                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;
+                        Signal* signal = *s;
 
-                if (w >= 0.0) {
+                        int over = signal_direction;
+                        over -= (signal_direction >= 0) ? 0 : 1;
+                        signal_direction -= (double)over;
 
-                        /* 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 {
-
-                        /* inverted width - reverse order of signal spread */
-
-                        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;
-                        }
+                        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;
                 }
-
         } else if (_signals.size() == 1) {
+                double center = _pannable->pan_azimuth_control->get_value() * 360.0;
 
                 /* width has no role to play if there is only 1 signal: VBAP does not do "diffusion" of a single channel */
 
@@ -516,7 +473,11 @@ void
 VBAPanner::reset ()
 {
 	set_position (0);
-	set_width (1);
+        if (_signals.size() > 1) {
+                set_width (1.0 - (1.0 / (double)_signals.size()));
+        } else {
+                set_width (0);
+        }
 	set_elevation (0);
 
 	update ();