Update to trunk

(bzr r15295.1.23)

7 files changed, 295 insertions, 45 deletions

diff --git a/src/desktop-style.cpp b/src/desktop-style.cpp
index dee36d681..4c07c76ea 100644
--- a/src/desktop-style.cpp
+++ b/src/desktop-style.cpp
@@ -209,7 +209,7 @@ sp_desktop_set_style(Inkscape::ObjectSet *set, SPDesktop *desktop, SPCSSAttr *cs
     if (!change)
         return;
 
-// 2. Emit signal... See desktop->connectStyleSet in text-tool, tweak-tool, and gradient-drag.
+// 2. Emit signal... See desktop->connectSetStyle in text-tool, tweak-tool, and gradient-drag.
     bool intercepted = desktop->_set_style_signal.emit(css);
 
 /** \todo
@@ -1045,6 +1045,7 @@ objects_query_fontnumbers (const std::vector<SPItem*> &objects, SPStyle *style_r
     bool lineheight_normal = false;
     bool lineheight_unit_proportional = false;
     bool lineheight_unit_absolute = false;
+    bool lineheight_set = false; // Set true if any object has lineheight set.
 
     double size_prev = 0;
     double letterspacing_prev = 0;
@@ -1130,6 +1131,9 @@ objects_query_fontnumbers (const std::vector<SPItem*> &objects, SPStyle *style_r
             lineheight_normal = false;
             lineheight += lineheight_current * doc_scale;
         }
+        if (style->line_height.set) {
+            lineheight_set = true;
+        }
 
         if ((size_prev != 0 && style->font_size.computed != size_prev) ||
             (letterspacing_prev != 0 && style->letter_spacing.computed != letterspacing_prev) ||
@@ -1205,6 +1209,9 @@ objects_query_fontnumbers (const std::vector<SPItem*> &objects, SPStyle *style_r
         }
     }
 
+    // Used by text toolbar unset 'line-height' 
+    style_res->line_height.set = lineheight_set;
+
     if (texts > 1) {
         if (different || different_lineheight) {
             return QUERY_STYLE_MULTIPLE_AVERAGED;
@@ -1907,7 +1914,7 @@ sp_desktop_query_style_from_list (const std::vector<SPItem*> &list, SPStyle *sty
 int
 sp_desktop_query_style(SPDesktop *desktop, SPStyle *style, int property)
 {
-    // Used by text tool and in gradient dragging
+    // Used by text tool and in gradient dragging. See connectQueryStyle.
     int ret = desktop->_query_style_signal.emit(style, property);
 
     if (ret != QUERY_STYLE_NOTHING)
diff --git a/src/file.cpp b/src/file.cpp
index 55089209a..8f283e1f8 100644
--- a/src/file.cpp
+++ b/src/file.cpp
@@ -66,6 +66,10 @@
 // For updating old Inkscape SVG files
 #include "display/canvas-grid.h"
 #include "sp-guide.h"
+#include "selection-chemistry.h"
+#include "persp3d.h"
+#include "proj_pt.h"
+#include "ui/shape-editor.h"
 
 #include <gtkmm.h>
 
@@ -353,11 +357,13 @@ bool sp_file_open(const Glib::ustring &uri,
                 bool need_fix_units   = false;
                 bool need_fix_guides  = false;
                 bool need_fix_grid_mm = false;
-                bool is_extension = false;
+                bool need_fix_box3d   = false;
+                bool did_scaling = false;
 
                 // Check if potentially need viewbox or unit fix
                 switch (root->width.unit) {
                     case SP_CSS_UNIT_PC:
+                    case SP_CSS_UNIT_PT:
                     case SP_CSS_UNIT_MM:
                     case SP_CSS_UNIT_CM:
                     case SP_CSS_UNIT_IN:
@@ -366,13 +372,19 @@ bool sp_file_open(const Glib::ustring &uri,
                     case SP_CSS_UNIT_NONE:
                     case SP_CSS_UNIT_PX:
                         need_fix_units = true;
-                    default:
                         break;
+                    case SP_CSS_UNIT_EM:
+                    case SP_CSS_UNIT_EX:
+                    case SP_CSS_UNIT_PERCENT:
                         // OK
+                        break;
+                    default:
+                        std::cerr << "sp_file_open: Unhandled width unit!" << std::endl;
                 }
 
                 switch (root->height.unit) {
                     case SP_CSS_UNIT_PC:
+                    case SP_CSS_UNIT_PT:
                     case SP_CSS_UNIT_MM:
                     case SP_CSS_UNIT_CM:
                     case SP_CSS_UNIT_IN:
@@ -381,14 +393,21 @@ bool sp_file_open(const Glib::ustring &uri,
                     case SP_CSS_UNIT_NONE:
                     case SP_CSS_UNIT_PX:
                         need_fix_units = true;
-                    default:
                         break;
+                    case SP_CSS_UNIT_EM:
+                    case SP_CSS_UNIT_EX:
+                    case SP_CSS_UNIT_PERCENT:
                         // OK
+                        break;
+                    default:
+                        std::cerr << "sp_file_open: Unhandled height unit!" << std::endl;
                 }
 
                 // std::cout << "Absolute SVG units in root? " << (need_fix_viewbox?"true":"false") << std::endl;
                 // std::cout << "User units in root? "         << (need_fix_units  ?"true":"false") << std::endl;
 
+                Inkscape::Preferences *prefs = Inkscape::Preferences::get();
+
                 if (!root->viewBox_set && need_fix_viewbox) {
 
                     Glib::ustring msg = _(
@@ -401,31 +420,37 @@ bool sp_file_open(const Glib::ustring &uri,
                     Gtk::Label info;
                     info.set_markup(msg.c_str());
                     info.show();
-
                     scaleDialog.get_content_area()->pack_start(info, false, false, 20);
+
                     Gtk::CheckButton backupButton( _("Create backup file (in same directory).") );
-                    backupButton.set_active();
+                    bool backup = prefs->getBool("/options/dpifixbackup", true);
+                    backupButton.set_active( backup );
                     backupButton.show();
-
                     scaleDialog.get_content_area()->pack_start(backupButton, false, false, 20);
-                    scaleDialog.add_button("Set 'viewBox'", 1);
-                    scaleDialog.add_button("Scale elements", 2);
-                    scaleDialog.add_button("Ignore",        3);
+
+                    scaleDialog.add_button(_("Set 'viewBox'"),   1);
+                    scaleDialog.add_button(_("Scale elements"),  2);
+                    scaleDialog.add_button(_("Ignore"),          3);
+                    scaleDialog.add_button("Scale test - group",    4);
+                    scaleDialog.add_button("Scale test - children", 5);
 
                     gint response = scaleDialog.run();
-                    bool backup = backupButton.get_active();
+                    backup = backupButton.get_active();
+                    prefs->setBool("/options/dpifixbackup", backup);
+
+                    if ( backup && response != 3) {
+                        sp_file_save_backup( uri );
+                    }
+
                     if (response == 1) {
-                        if (backup) {
-                            sp_file_save_backup( uri );
-                        }
+
                         doc->setViewBox(Geom::Rect::from_xywh(
                                             0, 0,
                                             doc->getWidth().value("px") * ratio,
                                             doc->getHeight().value("px") * ratio));
+
                     } else if (response == 2 ) {
-                        if (backup) {
-                            sp_file_save_backup( uri );
-                        }
+
                         std::list<Inkscape::Extension::Effect *> effects;
                         Inkscape::Extension::db.get_effect_list(effects);
                         std::list<Inkscape::Extension::Effect *>::iterator it = effects.begin();
@@ -442,12 +467,65 @@ bool sp_file_open(const Glib::ustring &uri,
                         if (!did) {
                             std::cerr << "sp_file_open: Failed to find dpi90to96 extension." << std::endl;
                         }
-                        is_extension = true;
+                        did_scaling = true;
+
+                    } else if (response == 4) {
+
+                        // Save preferences
+                        bool onlysensitive = prefs->getBool("/options/kbselection/onlysensitive",true);
+                        bool onlyvisible   = prefs->getBool("/options/kbselection/onlyvisible",  true);
+
+                        prefs->setBool("/options/kbselection/onlysensitive", false);
+                        prefs->setBool("/options/kbselection/onlyvisible",   false);
+
+                        Inkscape::Selection *selection = desktop->getSelection();
+                        Inkscape::SelectionHelper::selectAllInAll( desktop );
+                        selection->group();
+                        SPItem * group = selection->singleItem();
+                        if (group) {
+                            group->setAttribute("transform","scale(1.06666667,1.06666667)");
+                        } else {
+                            std::cerr << "sp_file_open: Failed to get group!" << std::endl;
+                        }
+                        selection->clear();
+                        selection->add( group );
+                        selection->ungroup();
+                        selection->clear();
+
+                        prefs->setBool("/options/kbselection/onlysensitive", onlysensitive);
+                        prefs->setBool("/options/kbselection/onlyvisible",   onlyvisible  );
+
+                        did_scaling = true;
+
+                    } else if (response == 5) {
+
+                        // Save preferences
+                        bool transform_stroke      = prefs->getBool("/options/transform/stroke", true);
+                        bool transform_rectcorners = prefs->getBool("/options/transform/rectcorners", true);
+                        bool transform_pattern     = prefs->getBool("/options/transform/pattern", true);
+                        bool transform_gradient    = prefs->getBool("/options/transform/gradient", true);
+
+                        prefs->setBool("/options/transform/stroke",      true);
+                        prefs->setBool("/options/transform/rectcorners", true);
+                        prefs->setBool("/options/transform/pattern",     true);
+                        prefs->setBool("/options/transform/gradient",    true);
+
+                        Inkscape::UI::ShapeEditor::blockSetItem(true);
+                        doc->getRoot()->scaleChildItemsRec(Geom::Scale(1/ratio),Geom::Point(0, 0), false);
+                        Inkscape::UI::ShapeEditor::blockSetItem(false);
+
+                        // Restore preferences
+                        prefs->setBool("/options/transform/stroke",      transform_stroke);
+                        prefs->setBool("/options/transform/rectcorners", transform_rectcorners);
+                        prefs->setBool("/options/transform/pattern",     transform_pattern);
+                        prefs->setBool("/options/transform/gradient",    transform_gradient);
                     }
+
+                    need_fix_box3d = true;
                     need_fix_guides = true; // Always fix guides
                 }
 
-                if (need_fix_units) {
+                else if (need_fix_units) {
                     Glib::ustring msg = (
                         "Old Inkscape files use 1in == 90px. CSS requires 1in == 96px.\n"
                         "Drawings meant to match a physical size (e.g. Letter or A4)\n"
@@ -462,19 +540,27 @@ bool sp_file_open(const Glib::ustring &uri,
                     scaleDialog.get_content_area()->pack_start(info, false, false, 20);
 
                     Gtk::CheckButton backupButton( _("Create backup file (in same directory).") );
-                    scaleDialog.get_content_area()->pack_start(backupButton, false, false, 20);
+                    bool backup = prefs->getBool("/options/dpifixbackup", true);
+                    backupButton.set_active( backup );
                     backupButton.show();
+                    scaleDialog.get_content_area()->pack_start(backupButton, false, false, 20);
 
-                    scaleDialog.add_button("Set 'viewBox'",  1);
-                    scaleDialog.add_button("Scale elements", 2);
-                    scaleDialog.add_button("Ignore",         3);
+                    scaleDialog.add_button(_("Set 'viewBox'"),  1);
+                    scaleDialog.add_button(_("Scale elements"), 2);
+                    scaleDialog.add_button(_("Ignore"),         3);
+                    scaleDialog.add_button("Scale test - group",    4);
+                    scaleDialog.add_button("Scale test - children", 5);
 
                     gint response = scaleDialog.run();
-                    bool backup = backupButton.get_active();
+                    backup = backupButton.get_active();
+                    prefs->setBool("/options/dpifixbackup", backup);
+
+                    if ( backup && response != 3) {
+                        sp_file_save_backup( uri );
+                    }
+
                     if (response == 1) {
-                        if (backup) {
-                            sp_file_save_backup( uri );
-                        }
+
                         if (!root->viewBox_set) {
                             doc->setViewBox(Geom::Rect::from_xywh(
                                                 0, 0,
@@ -488,10 +574,10 @@ bool sp_file_open(const Glib::ustring &uri,
                         doc->setWidthAndHeight( width, height, false );
 
                         need_fix_guides = true; // Only fix guides if drawing scaled
+                        need_fix_box3d = true;
+
                     } else if (response == 2) {
-                        if (backup) {
-                            sp_file_save_backup( uri );
-                        }
+
                         std::list<Inkscape::Extension::Effect *> effects;
                         Inkscape::Extension::db.get_effect_list(effects);
                         std::list<Inkscape::Extension::Effect *>::iterator it = effects.begin();
@@ -509,14 +595,94 @@ bool sp_file_open(const Glib::ustring &uri,
                             std::cerr << "sp_file_open: Failed to find dpi90to96 extension." << std::endl;
                         }
                         need_fix_guides = true; // Only fix guides if drawing scaled
-                        is_extension = true;
+                        did_scaling = true;
+
+                    } else if (response == 4) {
+
+                        Inkscape::Util::Quantity width  =
+                            Inkscape::Util::Quantity(doc->getWidth().value("px")/ratio, "px" );
+                        Inkscape::Util::Quantity height =
+                            Inkscape::Util::Quantity(doc->getHeight().value("px")/ratio,"px" );
+                        doc->setWidthAndHeight( width, height, false );
+
+                        if (!root->viewBox_set) {
+
+                            // Save preferences
+                            Inkscape::Preferences *prefs = Inkscape::Preferences::get();
+                            bool onlysensitive = prefs->getBool("/options/kbselection/onlysensitive",true);
+                            bool onlyvisible   = prefs->getBool("/options/kbselection/onlyvisible",  true);
+
+                            prefs->setBool("/options/kbselection/onlysensitive", false);
+                            prefs->setBool("/options/kbselection/onlyvisible",   false);
+
+                            Inkscape::Selection *selection = desktop->getSelection();
+                            Inkscape::SelectionHelper::selectAllInAll( desktop );
+                            selection->group();
+                            SPItem * group = selection->singleItem();
+                            if (group) {
+                                group->setAttribute("transform","scale(1.06666667,1.06666667)");
+                            } else {
+                                std::cerr << "sp_file_open: Failed to get group!" << std::endl;
+                            }
+                            selection->clear();
+                            selection->add( group );
+                            selection->ungroup();
+                            selection->clear();
+
+                            prefs->setBool("/options/kbselection/onlysensitive", onlysensitive);
+                            prefs->setBool("/options/kbselection/onlyvisible",   onlyvisible  );
+
+                            did_scaling = true;
+                        }
+
+                        need_fix_box3d = true;
+                        need_fix_guides = true; // Only fix guides if drawing scaled
+
+                    } else if (response == 5) {
+
+                        Inkscape::Util::Quantity width  =
+                            Inkscape::Util::Quantity(doc->getWidth().value("px")/ratio, "px" );
+                        Inkscape::Util::Quantity height =
+                            Inkscape::Util::Quantity(doc->getHeight().value("px")/ratio,"px" );
+                        doc->setWidthAndHeight( width, height, false );
+
+                        if (!root->viewBox_set) {
+
+                            // Save preferences
+                            Inkscape::Preferences *prefs = Inkscape::Preferences::get();
+                            bool transform_stroke      = prefs->getBool("/options/transform/stroke", true);
+                            bool transform_rectcorners = prefs->getBool("/options/transform/rectcorners", true);
+                            bool transform_pattern     = prefs->getBool("/options/transform/pattern", true);
+                            bool transform_gradient    = prefs->getBool("/options/transform/gradient", true);
+
+                            prefs->setBool("/options/transform/stroke",      true);
+                            prefs->setBool("/options/transform/rectcorners", true);
+                            prefs->setBool("/options/transform/pattern",     true);
+                            prefs->setBool("/options/transform/gradient",    true);
+
+                            Inkscape::UI::ShapeEditor::blockSetItem(true);
+                            doc->getRoot()->scaleChildItemsRec(Geom::Scale(1/ratio),Geom::Point(0, 0), false);
+                            Inkscape::UI::ShapeEditor::blockSetItem(false);
+
+                            // Restore preferences
+                            prefs->setBool("/options/transform/stroke",      transform_stroke);
+                            prefs->setBool("/options/transform/rectcorners", transform_rectcorners);
+                            prefs->setBool("/options/transform/pattern",     transform_pattern);
+                            prefs->setBool("/options/transform/gradient",    transform_gradient);
+
+                            did_scaling = true;
+                        }
+
+                        need_fix_box3d = true;
+                        need_fix_guides = true; // Only fix guides if drawing scaled
+
                     } else {
                         // Ignore
                         need_fix_grid_mm = true;
                     }
                 }
 
-                // Fix guides and grids
+                // Fix guides and grids and perspective
                 for (SPObject *child = root->firstChild() ; child; child = child->getNext() ) {
                     SPNamedView *nv = dynamic_cast<SPNamedView *>(child);
                     if (nv) {
@@ -555,21 +721,53 @@ bool sp_file_open(const Glib::ustring &uri,
                                     }
                                 } else {
                                     if (need_fix_guides) {
-                                        // HACK: Scaling the document does not seem to cause
-                                        // grids defined in document units to be updated.
-                                        // This forces an update.
-                                        if(is_extension){
+                                        if(did_scaling){
                                             xy->Scale( Geom::Scale(ratio,ratio).inverse() );
                                         } else {
+                                            // HACK: Scaling the document does not seem to cause
+                                            // grids defined in document units to be updated.
+                                            // This forces an update.
                                             xy->Scale( Geom::Scale(1,1) );
                                         }
                                     }
                                 }
                             }
                         }
+                    }  // If SPNamedView
+
+                    SPDefs *defs = dynamic_cast<SPDefs *>(child);
+                    if (defs && need_fix_box3d) {
+                        for (SPObject *child = defs->firstChild() ; child; child = child->getNext() ) {
+                            Persp3D* persp3d = dynamic_cast<Persp3D *>(child);
+                            if (persp3d) {
+                                std::vector<Glib::ustring> tokens;
+
+                                const gchar* vp_x = persp3d->getAttribute("inkscape:vp_x");
+                                const gchar* vp_y = persp3d->getAttribute("inkscape:vp_y");
+                                const gchar* vp_z = persp3d->getAttribute("inkscape:vp_z");
+                                const gchar* vp_o = persp3d->getAttribute("inkscape:persp3d-origin");
+                                // std::cout << "Found Persp3d: "
+                                //           << " vp_x: " << vp_x
+                                //           << " vp_y: " << vp_y
+                                //           << " vp_z: " << vp_z << std::endl;
+                                Proj::Pt2 pt_x (vp_x);
+                                Proj::Pt2 pt_y (vp_y);
+                                Proj::Pt2 pt_z (vp_z);
+                                Proj::Pt2 pt_o (vp_o);
+                                pt_x = pt_x * (1.0/ratio);
+                                pt_y = pt_y * (1.0/ratio);
+                                pt_z = pt_z * (1.0/ratio);
+                                pt_o = pt_o * (1.0/ratio);
+                                persp3d->setAttribute("inkscape:vp_x",pt_x.coord_string());
+                                persp3d->setAttribute("inkscape:vp_y",pt_y.coord_string());
+                                persp3d->setAttribute("inkscape:vp_z",pt_z.coord_string());
+                                persp3d->setAttribute("inkscape:persp3d-origin",pt_o.coord_string());
+                            }
+                        }
                     }
-                }  // Look for SPNamedView loop
+                }  // Look for SPNamedView and SPDefs loop
 
+                // desktop->getDocument()->ensureUpToDate();  // Does not update box3d!
                 DocumentUndo::done(desktop->getDocument(), SP_VERB_NONE, _("Update Document"));
 
             }  // If old Inkscape version
diff --git a/src/sp-item-group.cpp b/src/sp-item-group.cpp
index 96dcdbe30..7b2507b5e 100644
--- a/src/sp-item-group.cpp
+++ b/src/sp-item-group.cpp
@@ -584,12 +584,13 @@ sp_item_group_ungroup (SPGroup *group, std::vector<SPItem*> &children, bool do_d
             SPText * text = dynamic_cast<SPText *>(citem);
             if (text) {
                 //this causes a change in text-on-path appearance when there is a non-conformal transform, see bug #1594565
-                double scale = (ctrans.expansionX() + ctrans.expansionY()) / 2.0;
                 SPTextPath * text_path = dynamic_cast<SPTextPath *>(text->firstChild());
                 if (!text_path) {
                     nrepr->setAttribute("transform", affinestr);
                 } else {
-                    sp_recursive_scale_text_size(nrepr, scale);
+                    // The following breaks roundtripping  group -> ungroup
+                    // double scale = (ctrans.expansionX() + ctrans.expansionY()) / 2.0;
+                    // sp_recursive_scale_text_size(nrepr, scale);
                     Geom::Affine ttrans = ctrans.inverse() * SP_ITEM(text)->transform * ctrans;
                     gchar *affinestr = sp_svg_transform_write(ttrans);
                     nrepr->setAttribute("transform", affinestr);
diff --git a/src/sp-mesh-array.cpp b/src/sp-mesh-array.cpp
index b522d577b..f192d0e44 100644
--- a/src/sp-mesh-array.cpp
+++ b/src/sp-mesh-array.cpp
@@ -1198,7 +1198,7 @@ void SPMeshNodeArray::create( SPMeshGradient *mg, SPItem *item, Geom::OptRect bb
             ry = arc->ry.computed;
             start = arc->start;
             end   = arc->end;
-            if( end == start ) {
+            if( end <= start ) {
                 end += 2.0 * M_PI;
             }
         }
diff --git a/src/ui/tools/tweak-tool.cpp b/src/ui/tools/tweak-tool.cpp
index 56939cc30..ff5d623c2 100644
--- a/src/ui/tools/tweak-tool.cpp
+++ b/src/ui/tools/tweak-tool.cpp
@@ -1084,7 +1084,8 @@ sp_tweak_dilate (TweakTool *tc, Geom::Point event_p, Geom::Point p, Geom::Point
     double move_force = get_move_force(tc);
     double color_force = MIN(sqrt(path_force)/20.0, 1);
 
-    auto items= selection->items();
+//    auto items= selection->items();
+    std::vector<SPItem*> items(selection->items().begin(), selection->items().end());
     for(auto i=items.begin();i!=items.end(); ++i){
         SPItem *item = *i;
 
diff --git a/src/widgets/text-toolbar.cpp b/src/widgets/text-toolbar.cpp
index 847ebd8c1..784c467f1 100644
--- a/src/widgets/text-toolbar.cpp
+++ b/src/widgets/text-toolbar.cpp
@@ -239,7 +239,7 @@ static void sp_text_fontsize_value_changed( Ink_ComboBoxEntry_Action *act, GObje
             if (dynamic_cast<SPText *>(*i) || dynamic_cast<SPFlowtext *>(*i)) {
                 SPItem *item = *i;
 
-                // Scale by inverse of accumulated paraent transform
+                // Scale by inverse of accumulated parent transform
                 SPCSSAttr *css_set = sp_repr_css_attr_new();
                 sp_repr_css_merge(css_set, css);
                 Geom::Affine const local(item->i2doc_affine());
@@ -321,6 +321,29 @@ static void sp_text_outer_style_changed( InkToggleAction*act, GObject *tbl )
     sp_text_toolbox_selection_changed( NULL, tbl );
 }
 
+// Unset line height on selection's inner text objects (tspan, etc.).
+static void sp_text_lineheight_unset_changed( InkToggleAction*act, GObject *tbl )
+{
+    // quit if run by the _changed callbacks
+    if (g_object_get_data(G_OBJECT(tbl), "freeze")) {
+        return;
+    }
+    g_object_set_data( tbl, "freeze", GINT_TO_POINTER(TRUE) );
+
+    SPCSSAttr *css = sp_repr_css_attr_new();
+    sp_repr_css_unset_property(css, "line-height");
+
+    SPDesktop *desktop = SP_ACTIVE_DESKTOP;
+    sp_desktop_set_style (desktop, css);
+
+    sp_repr_css_attr_unref(css);
+    
+    DocumentUndo::done(desktop->getDocument(), SP_VERB_CONTEXT_TEXT,
+                       _("Text: Unset line height."));
+
+    g_object_set_data( tbl, "freeze", GINT_TO_POINTER(FALSE) );
+}
+
 // Handles both Superscripts and Subscripts
 static void sp_text_script_changed( InkToggleAction* act, GObject *tbl )
 {
@@ -599,7 +622,7 @@ static void sp_text_lineheight_value_changed( GtkAdjustment *adj, GObject *tbl )
             if (dynamic_cast<SPText *>(*i) || dynamic_cast<SPFlowtext *>(*i)) {
                 SPItem *item = *i;
 
-                // Scale by inverse of accumulated paraent transform
+                // Scale by inverse of accumulated parent transform
                 SPCSSAttr *css_set = sp_repr_css_attr_new();
                 sp_repr_css_merge(css_set, css);
                 Geom::Affine const local(item->i2doc_affine());
@@ -1405,7 +1428,13 @@ static void sp_text_toolbox_selection_changed(Inkscape::Selection */*selection*/
         }
         // Save unit so we can do convertions between new/old units.
         g_object_set_data( tbl, "lineheight_unit", GINT_TO_POINTER(line_height_unit));
-        
+
+        // Enable and turn on only if selection includes an object with line height set.
+        InkToggleAction* lineHeightUnset =
+            INK_TOGGLE_ACTION( g_object_get_data( tbl, "TextLineHeightUnsetAction"));
+        gtk_action_set_sensitive(GTK_ACTION(lineHeightUnset), query.line_height.set );
+        gtk_toggle_action_set_active( GTK_TOGGLE_ACTION(lineHeightUnset), query.line_height.set );
+
         // Word spacing
         double wordSpacing;
         if (query.word_spacing.normal) wordSpacing = 0.0;
@@ -2100,6 +2129,19 @@ void sp_text_toolbox_prep(SPDesktop *desktop, GtkActionGroup* mainActions, GObje
         g_object_set( G_OBJECT(eact), "iconId", "text_rotation", NULL );
     }
 
+    /* Text line height unset */
+    {
+        InkToggleAction* act = ink_toggle_action_new( "TextLineHeightUnsetAction",       // Name
+                                                      _("Unset line height"),            // Label
+                                                      _("If enabled, line height is set on part of selection. Click to unset."),
+                                                      INKSCAPE_ICON("paint-unknown"),
+                                                      secondarySize );                   // Icon size
+        gtk_action_group_add_action( mainActions, GTK_ACTION( act ) );
+        g_signal_connect_after( G_OBJECT(act), "toggled", G_CALLBACK(sp_text_lineheight_unset_changed), holder );
+        gtk_toggle_action_set_active( GTK_TOGGLE_ACTION(act), prefs->getBool("/tools/text/line_height_unset", false) );
+        g_object_set_data( holder, "TextLineHeightUnsetAction", act );
+    }
+
     /* Text outer style */
     {
         InkToggleAction* act = ink_toggle_action_new( "TextOuterStyleAction",            // Name
diff --git a/src/widgets/toolbox.cpp b/src/widgets/toolbox.cpp
index 1f6cb136c..a3db3c33d 100644
--- a/src/widgets/toolbox.cpp
+++ b/src/widgets/toolbox.cpp
@@ -514,6 +514,7 @@ static gchar const * ui_descr =
         "    <toolitem action='TextFontSizeAction' />"
         "    <toolitem action='TextLineHeightAction' />"
         "    <toolitem action='TextLineHeightUnitsAction' />"
+        "    <toolitem action='TextLineHeightUnsetAction' />"
         "    <separator />"
         "    <toolitem action='TextAlignAction' />"
         "    <separator />"