2 files changed, 35 insertions, 6 deletions

diff --git a/src/ui/widget/registered-widget.cpp b/src/ui/widget/registered-widget.cpp
index e97285de4..4065bd550 100644
--- a/src/ui/widget/registered-widget.cpp
+++ b/src/ui/widget/registered-widget.cpp
@@ -36,6 +36,8 @@
 // for interruptability bug:
 #include "display/sp-canvas.h"
 
+#include "sp-root.h"
+
 namespace Inkscape {
 namespace UI {
 namespace Widget {
@@ -203,7 +205,7 @@ RegisteredScalarUnit::~RegisteredScalarUnit()
     _value_changed_connection.disconnect();
 }
 
-RegisteredScalarUnit::RegisteredScalarUnit (const Glib::ustring& label, const Glib::ustring& tip, const Glib::ustring& key, const RegisteredUnitMenu &rum, Registry& wr, Inkscape::XML::Node* repr_in, SPDocument *doc_in)
+RegisteredScalarUnit::RegisteredScalarUnit (const Glib::ustring& label, const Glib::ustring& tip, const Glib::ustring& key, const RegisteredUnitMenu &rum, Registry& wr, Inkscape::XML::Node* repr_in, SPDocument *doc_in, RSU_UserUnits user_units)
     : RegisteredWidget<ScalarUnit>(label, tip, UNIT_TYPE_LINEAR, "", "", rum.getUnitMenu()),
       _um(0)
 {
@@ -215,6 +217,7 @@ RegisteredScalarUnit::RegisteredScalarUnit (const Glib::ustring& label, const Gl
     setUnit (rum.getUnitMenu()->getUnitAbbr());
     setDigits (2);
     _um = rum.getUnitMenu();
+    _user_units = user_units;
     _value_changed_connection = signal_value_changed().connect (sigc::mem_fun (*this, &RegisteredScalarUnit::on_value_changed));
 }
 
@@ -233,12 +236,28 @@ RegisteredScalarUnit::on_value_changed()
     _wr->setUpdating (true);
 
     Inkscape::SVGOStringStream os;
-    os << getValue("");
-    if (_um)
-        os << _um->getUnitAbbr();
+    if (_user_units != RSU_none) {
+        // Output length in 'user units', taking into account scale in 'x' or 'y'.
+        double scale = 1.0;
+        if (doc) {
+            SPRoot *root = doc->getRoot();
+            if (root->viewBox_set) {
+                if (_user_units == RSU_x) { 
+                    scale = root->viewBox.width() / root->width.computed;
+                } else {
+                    scale = root->viewBox.height() / root->height.computed;
+                }
+            }
+        }
+        os << getValue("px") * scale;
+    } else {
+        // Output using unit identifiers.
+        os << getValue("");
+        if (_um)
+            os << _um->getUnitAbbr();
+    }
 
     write_to_xml(os.str().c_str());
-
     _wr->setUpdating (false);
 }
 
diff --git a/src/ui/widget/registered-widget.h b/src/ui/widget/registered-widget.h
index 1f505a3cd..15302a165 100644
--- a/src/ui/widget/registered-widget.h
+++ b/src/ui/widget/registered-widget.h
@@ -206,6 +206,14 @@ protected:
     void on_changed();
 };
 
+// Allow RegisteredScalarUnit to output lengths in 'user units' (which may have direction dependent
+// scale factors).
+enum RSU_UserUnits {
+    RSU_none,
+    RSU_x,
+    RSU_y
+};
+
 class RegisteredScalarUnit : public RegisteredWidget<ScalarUnit> {
 public:
     ~RegisteredScalarUnit();
@@ -215,12 +223,14 @@ public:
                            const RegisteredUnitMenu &rum,
                            Registry& wr,
                            Inkscape::XML::Node* repr_in = NULL,
-                           SPDocument *doc_in = NULL );
+                           SPDocument *doc_in = NULL,
+                           RSU_UserUnits _user_units = RSU_none );
 
 protected:
     sigc::connection  _value_changed_connection;
     UnitMenu         *_um;
     void on_value_changed();
+    RSU_UserUnits _user_units;
 };
 
 class RegisteredScalar : public RegisteredWidget<Scalar> {