allow alt-drag on stereo panner to move just one side of the stereo field. this wiggles a bit, possibly because of rounding, and that probably needs to be addressed

git-svn-id: svn://localhost/ardour2/branches/3.0@12500 d708f5d6-7413-0410-9779-e7cbd77b26cf

2 files changed, 14 insertions, 0 deletions

diff --git a/libs/panners/2in2out/panner_2in2out.cc b/libs/panners/2in2out/panner_2in2out.cc
index 8e798315d0..57b8836787 100644
--- a/libs/panners/2in2out/panner_2in2out.cc
+++ b/libs/panners/2in2out/panner_2in2out.cc
@@ -124,8 +124,21 @@ Panner2in2out::set_width (double p)
 }
 
 void
+Panner2in2out::thaw ()
+{
+	Panner::thaw ();
+	if (_frozen == 0) {
+		update ();
+	}
+}
+
+void
 Panner2in2out::update ()
 {
+	if (_frozen) {
+		return;
+	}
+
         /* it would be very nice to split this out into a virtual function
            that can be accessed from BaseStereoPanner and used in do_distribute_automated().
            
diff --git a/libs/panners/2in2out/panner_2in2out.h b/libs/panners/2in2out/panner_2in2out.h
index 232d63ec62..001d3064e8 100644
--- a/libs/panners/2in2out/panner_2in2out.h
+++ b/libs/panners/2in2out/panner_2in2out.h
@@ -67,6 +67,7 @@ class Panner2in2out : public Panner
         void update ();
 
 	void reset ();
+        void thaw ();
 
   protected:
 	float left[2];