diff --git a/rtgui/controllines.cc b/rtgui/controllines.cc
index c078b4322..14454e2ef 100644
--- a/rtgui/controllines.cc
+++ b/rtgui/controllines.cc
@@ -16,6 +16,7 @@
  *  You should have received a copy of the GNU General Public License
  *  along with RawTherapee.  If not, see <https://www.gnu.org/licenses/>.
  */
+#include <assert.h>
 #include <memory>
 
 #include "controllines.h"
@@ -27,6 +28,53 @@
 
 using namespace rtengine;
 
+enum GeometryIndex {
+    MO_CANVAS,
+    MO_OBJECT_COUNT,
+
+    VISIBLE_OBJECT_COUNT = 0
+};
+
+/**
+ * Offsets for mouse-over geometry that can be compared to the mouse-over object
+ * ID modded with the control line object count.
+ */
+enum GeometryOffset {
+    OFFSET_LINE = (MO_OBJECT_COUNT + ::ControlLine::LINE) % ::ControlLine::OBJECT_COUNT,
+    OFFSET_ICON = (MO_OBJECT_COUNT + ::ControlLine::ICON) % ::ControlLine::OBJECT_COUNT,
+    OFFSET_BEGIN = (MO_OBJECT_COUNT + ::ControlLine::BEGIN) % ::ControlLine::OBJECT_COUNT,
+    OFFSET_END = (MO_OBJECT_COUNT + ::ControlLine::END) % ::ControlLine::OBJECT_COUNT,
+};
+
+namespace
+{
+
+/**
+ * Returns true if the object matches the offset.
+ */
+constexpr bool checkOffset(int object_id, enum GeometryOffset offset)
+{
+    return object_id % ::ControlLine::OBJECT_COUNT == offset;
+}
+
+/**
+ * Converts a control line mouse-over geometry ID to the visible geometry ID.
+ */
+constexpr int mouseOverIdToVisibleId(int mouse_over_id)
+{
+    return mouse_over_id - MO_OBJECT_COUNT + VISIBLE_OBJECT_COUNT;
+}
+
+/**
+ * Converts a control line mouse-over geometry ID to the control line ID.
+ */
+constexpr int mouseOverIdToLineId(int mouse_over_id)
+{
+    return (mouse_over_id - MO_OBJECT_COUNT) / ::ControlLine::OBJECT_COUNT;
+}
+
+}
+
 ::ControlLine::~ControlLine() = default;
 
 ControlLineManager::ControlLineManager():
@@ -96,17 +144,20 @@ bool ControlLineManager::button1Pressed(int modifierKey)
 
     const int object = dataProvider->getObject();
 
-    if (object > 0) { // A control line.
-        if (object % ::ControlLine::OBJ_COUNT == 2) { // Icon.
+    if (object >= MO_OBJECT_COUNT) { // A control line.
+        if (checkOffset(object, OFFSET_ICON)) { // Icon.
             action = Action::PICKING;
         } else {
             selected_object = object;
             action = Action::DRAGGING;
         }
     } else if (draw_mode && (modifierKey & GDK_CONTROL_MASK)) { // Add new line.
+        if (object < 0) {
+            return false;
+        }
         addLine(dataProvider->posImage, dataProvider->posImage);
         drawing_line = true;
-        selected_object = mouseOverGeometry.size() - 1; // Select endpoint.
+        selected_object = mouseOverGeometry.size() - ::ControlLine::OBJECT_COUNT + ::ControlLine::END; // Select endpoint.
         action = Action::DRAGGING;
     }
 
@@ -117,7 +168,7 @@ bool ControlLineManager::button1Released(void)
 {
     action = Action::NONE;
 
-    if (selected_object > 0) {
+    if (selected_object >= MO_OBJECT_COUNT) {
         mouseOverGeometry[selected_object]->state = Geometry::NORMAL;
     }
 
@@ -125,7 +176,7 @@ bool ControlLineManager::button1Released(void)
     callbacks->lineChanged();
     drawing_line = false;
     selected_object = -1;
-    return false;
+    return true;
 }
 
 bool ControlLineManager::button3Pressed(int modifierKey)
@@ -134,12 +185,12 @@ bool ControlLineManager::button3Pressed(int modifierKey)
 
     action = Action::NONE;
 
-    if (!provider || provider->getObject() < 1) {
+    if (!provider || provider->getObject() < MO_OBJECT_COUNT) {
         return false;
     }
 
     action = Action::PICKING;
-    return false;
+    return true;
 }
 
 bool ControlLineManager::pick1(bool picked)
@@ -152,14 +203,13 @@ bool ControlLineManager::pick1(bool picked)
 
     EditDataProvider* provider = getEditProvider();
 
-    if (!provider || provider->getObject() % ::ControlLine::OBJ_COUNT != 2) {
+    if (!provider || !checkOffset(provider->getObject(), OFFSET_ICON)) {
         return false;
     }
 
     // Change line type.
     int object_id = provider->getObject();
-    ::ControlLine& line =
-        *control_lines[(object_id - 1) / ::ControlLine::OBJ_COUNT];
+    ::ControlLine& line = *control_lines[mouseOverIdToLineId(object_id)];
 
     if (line.type == rtengine::ControlLine::HORIZONTAL) {
         line.icon = line.icon_v;
@@ -169,7 +219,7 @@ bool ControlLineManager::pick1(bool picked)
         line.type = rtengine::ControlLine::HORIZONTAL;
     }
 
-    visibleGeometry[object_id - 1] = line.icon.get();
+    visibleGeometry[mouseOverIdToVisibleId(object_id)] = line.icon.get();
 
     edited = true;
     callbacks->lineChanged();
@@ -191,38 +241,42 @@ bool ControlLineManager::pick3(bool picked)
         return false;
     }
 
-    removeLine((provider->getObject() - 1) / ::ControlLine::OBJ_COUNT);
+    removeLine(mouseOverIdToLineId(provider->getObject()));
     prev_obj = -1;
     selected_object = -1;
-    return false;
+    return true;
 }
 
 bool ControlLineManager::drag1(int modifierKey)
 {
+    if (action != Action::DRAGGING) {
+        return false;
+    }
+
     EditDataProvider* provider = getEditProvider();
 
-    if (!provider || selected_object < 1) {
+    if (!provider || selected_object < MO_OBJECT_COUNT) {
         return false;
     }
 
     ::ControlLine& control_line =
-        *control_lines[(selected_object - 1) / ::ControlLine::OBJ_COUNT];
+        *control_lines[mouseOverIdToLineId(selected_object)];
     // 0 == end, 1 == line, 2 == icon, 3 == begin
-    int component = selected_object % ::ControlLine::OBJ_COUNT;
+    int component = selected_object % ::ControlLine::OBJECT_COUNT;
     Coord mouse = provider->posImage + provider->deltaImage;
     Coord delta = provider->deltaImage - drag_delta;
     int ih, iw;
     provider->getImageSize(iw, ih);
 
     switch (component) {
-        case (0): // end
+        case (OFFSET_END): // end
             control_line.end->center = mouse;
             control_line.end->center.clip(iw, ih);
             control_line.line->end = control_line.end->center;
             control_line.end->state = Geometry::DRAGGED;
             break;
 
-        case (1): { // line
+        case (OFFSET_LINE): { // line
             // Constrain delta so the end stays above the image.
             Coord new_delta = control_line.end->center + delta;
             new_delta.clip(iw, ih);
@@ -241,7 +295,7 @@ bool ControlLineManager::drag1(int modifierKey)
             break;
         }
 
-        case (3): // begin
+        case (OFFSET_BEGIN): // begin
             control_line.begin->center = mouse;
             control_line.begin->center.clip(iw, ih);
             control_line.line->begin = control_line.begin->center;
@@ -260,7 +314,24 @@ bool ControlLineManager::drag1(int modifierKey)
         autoSetLineType(selected_object);
     }
 
-    return false;
+    return true;
+}
+
+void ControlLineManager::releaseEdit(void)
+{
+    action = Action::NONE;
+
+    if (selected_object >= MO_OBJECT_COUNT) {
+        mouseOverGeometry[selected_object]->state = Geometry::NORMAL;
+    }
+    if (prev_obj >= MO_OBJECT_COUNT) {
+        visibleGeometry[mouseOverIdToVisibleId(prev_obj)]->state = Geometry::NORMAL;
+    }
+
+    edited = true;
+    callbacks->lineChanged();
+    drawing_line = false;
+    selected_object = -1;
 }
 
 bool ControlLineManager::getEdited(void) const
@@ -283,7 +354,7 @@ bool ControlLineManager::mouseOver(int modifierKey)
 
     int cur_obj = provider->getObject();
 
-    if (cur_obj == 0) { // Canvas
+    if (cur_obj == MO_CANVAS) { // Canvas
         if (draw_mode && modifierKey & GDK_CONTROL_MASK) {
             cursor = CSCrosshair;
         } else {
@@ -291,16 +362,16 @@ bool ControlLineManager::mouseOver(int modifierKey)
         }
     } else if (cur_obj < 0) { // Nothing
         cursor = CSArrow;
-    } else if (cur_obj % ::ControlLine::OBJ_COUNT == 2) { // Icon
-        visibleGeometry[cur_obj - 1]->state = Geometry::PRELIGHT;
+    } else if (checkOffset(cur_obj, OFFSET_ICON)) { // Icon
+        visibleGeometry[mouseOverIdToVisibleId(cur_obj)]->state = Geometry::PRELIGHT;
         cursor = CSArrow;
     } else { // Object
-        visibleGeometry[cur_obj - 1]->state = Geometry::PRELIGHT;
+        visibleGeometry[mouseOverIdToVisibleId(cur_obj)]->state = Geometry::PRELIGHT;
         cursor = CSMove2D;
     }
 
-    if (prev_obj != cur_obj && prev_obj > 0) {
-        visibleGeometry[prev_obj - 1]->state = Geometry::NORMAL;
+    if (prev_obj != cur_obj && prev_obj >= MO_OBJECT_COUNT) {
+        visibleGeometry[mouseOverIdToVisibleId(prev_obj)]->state = Geometry::NORMAL;
     }
 
     prev_obj = cur_obj;
@@ -394,14 +465,29 @@ void ControlLineManager::addLine(Coord begin, Coord end,
     control_line->line = std::move(line);
     control_line->type = type;
 
+    auto assertEqual = [](size_t a, int b) {
+        assert(b >= 0);
+        assert(a == static_cast<size_t>(b));
+    };
+
+    const int base_visible_offset = VISIBLE_OBJECT_COUNT + ::ControlLine::OBJECT_COUNT * control_lines.size();
+    assertEqual(visibleGeometry.size(), base_visible_offset + ::ControlLine::LINE);
     EditSubscriber::visibleGeometry.push_back(control_line->line.get());
+    assertEqual(visibleGeometry.size(), base_visible_offset + ::ControlLine::ICON);
     EditSubscriber::visibleGeometry.push_back(control_line->icon.get());
+    assertEqual(visibleGeometry.size(), base_visible_offset + ::ControlLine::BEGIN);
     EditSubscriber::visibleGeometry.push_back(control_line->begin.get());
+    assertEqual(visibleGeometry.size(), base_visible_offset + ::ControlLine::END);
     EditSubscriber::visibleGeometry.push_back(control_line->end.get());
 
+    const int base_mo_count = MO_OBJECT_COUNT + ::ControlLine::OBJECT_COUNT * control_lines.size();
+    assertEqual(mouseOverGeometry.size(), base_mo_count + ::ControlLine::LINE);
     EditSubscriber::mouseOverGeometry.push_back(control_line->line.get());
+    assertEqual(mouseOverGeometry.size(), base_mo_count + ::ControlLine::ICON);
     EditSubscriber::mouseOverGeometry.push_back(control_line->icon.get());
+    assertEqual(mouseOverGeometry.size(), base_mo_count + ::ControlLine::BEGIN);
     EditSubscriber::mouseOverGeometry.push_back(control_line->begin.get());
+    assertEqual(mouseOverGeometry.size(), base_mo_count + ::ControlLine::END);
     EditSubscriber::mouseOverGeometry.push_back(control_line->end.get());
 
     control_lines.push_back(std::move(control_line));
@@ -409,7 +495,7 @@ void ControlLineManager::addLine(Coord begin, Coord end,
 
 void ControlLineManager::autoSetLineType(int object_id)
 {
-    int line_id = (object_id - 1) / ::ControlLine::OBJ_COUNT;
+    int line_id = mouseOverIdToLineId(object_id);
     ::ControlLine& line = *control_lines[line_id];
 
     int dx = line.begin->center.x - line.end->center.x;
@@ -437,7 +523,8 @@ void ControlLineManager::autoSetLineType(int object_id)
     if (type != line.type) { // Need to update line type.
         line.type = type;
         line.icon = icon;
-        visibleGeometry[line_id * ::ControlLine::OBJ_COUNT + 1] =
+        visibleGeometry[line_id * ::ControlLine::OBJECT_COUNT
++ VISIBLE_OBJECT_COUNT + ::ControlLine::ICON] =
             line.icon.get();
     }
 }
@@ -445,7 +532,7 @@ void ControlLineManager::autoSetLineType(int object_id)
 void ControlLineManager::removeAll(void)
 {
     visibleGeometry.clear();
-    mouseOverGeometry.erase(mouseOverGeometry.begin() + 1,
+    mouseOverGeometry.erase(mouseOverGeometry.begin() + MO_OBJECT_COUNT,
                             mouseOverGeometry.end());
     control_lines.clear();
     prev_obj = -1;
@@ -461,14 +548,13 @@ void ControlLineManager::removeLine(size_t line_id)
     }
 
     visibleGeometry.erase(
-        visibleGeometry.begin() + ::ControlLine::OBJ_COUNT * line_id,
-        visibleGeometry.begin() + ::ControlLine::OBJ_COUNT * line_id
-        + ::ControlLine::OBJ_COUNT
+        visibleGeometry.begin() + ::ControlLine::OBJECT_COUNT * line_id + VISIBLE_OBJECT_COUNT,
+        visibleGeometry.begin() + ::ControlLine::OBJECT_COUNT * line_id + VISIBLE_OBJECT_COUNT
+        + ::ControlLine::OBJECT_COUNT
     );
     mouseOverGeometry.erase(
-        mouseOverGeometry.begin() + ::ControlLine::OBJ_COUNT * line_id + 1,
-        mouseOverGeometry.begin() + ::ControlLine::OBJ_COUNT * line_id
-        + ::ControlLine::OBJ_COUNT + 1
+        mouseOverGeometry.begin() + ::ControlLine::OBJECT_COUNT * line_id + MO_OBJECT_COUNT,
+        mouseOverGeometry.begin() + ::ControlLine::OBJECT_COUNT * line_id + MO_OBJECT_COUNT + ::ControlLine::OBJECT_COUNT
     );
     control_lines.erase(control_lines.begin() + line_id);
 
diff --git a/rtgui/controllines.h b/rtgui/controllines.h
index 2b2d179a4..a05fb8b00 100644
--- a/rtgui/controllines.h
+++ b/rtgui/controllines.h
@@ -30,7 +30,14 @@ class Rectangle;
 class RTSurface;
 
 struct ControlLine {
-    static constexpr int OBJ_COUNT = 4;
+    enum ObjectIndex {
+        LINE,
+        ICON,
+        BEGIN,
+        END,
+        OBJECT_COUNT
+    };
+
     std::unique_ptr<Line> line;
     std::shared_ptr<OPIcon> icon;
     std::shared_ptr<OPIcon> icon_h, icon_v;
@@ -87,6 +94,8 @@ public:
     ~ControlLineManager();
 
     bool getEdited(void) const;
+    /** Release anything that is currently being dragged. */
+    void releaseEdit(void);
     void removeAll(void);
     /** Sets whether or not the lines are visible and interact-able. */
     void setActive(bool active);
diff --git a/rtgui/cropwindow.cc b/rtgui/cropwindow.cc
index 5a1debb23..b612de2e7 100644
--- a/rtgui/cropwindow.cc
+++ b/rtgui/cropwindow.cc
@@ -540,7 +540,7 @@ void CropWindow::buttonPress (int button, int type, int bstate, int x, int y)
                         action_y = 0;
                     }
 
-                } else if (iarea->getToolMode () == TMHand) {  // events outside of the image domain
+                } else if (iarea->getToolMode () == TMHand || iarea->getToolMode() == TMPerspective) {  // events outside of the image domain
                     EditSubscriber *editSubscriber = iarea->getCurrSubscriber();
 
                     if (editSubscriber && editSubscriber->getEditingType() == ET_OBJECTS) {
diff --git a/rtgui/gradient.cc b/rtgui/gradient.cc
index 972105dd0..af6503b45 100644
--- a/rtgui/gradient.cc
+++ b/rtgui/gradient.cc
@@ -12,6 +12,14 @@
 using namespace rtengine;
 using namespace rtengine::procparams;
 
+enum GeometryIndex {
+    H_LINE,
+    V_LINE,
+    FEATHER_LINE_1,
+    FEATHER_LINE_2,
+    CENTER_CIRCLE,
+};
+
 Gradient::Gradient () : FoldableToolPanel(this, "gradient", M("TP_GRADIENT_LABEL"), false, true), EditSubscriber(ET_OBJECTS), lastObject(-1), draggedPointOldAngle(-1000.)
 {
 
@@ -191,24 +199,24 @@ void Gradient::updateGeometry(const int centerX, const int centerY, const double
     };
 
     // update horizontal line
-    updateLine (visibleGeometry.at(0), 1500., 0., 180.);
-    updateLine (mouseOverGeometry.at(0), 1500., 0., 180.);
+    updateLine (visibleGeometry.at(H_LINE), 1500., 0., 180.);
+    updateLine (mouseOverGeometry.at(H_LINE), 1500., 0., 180.);
 
     // update vertical line
-    updateLine (visibleGeometry.at(1), 700., 90., 270.);
-    updateLine (mouseOverGeometry.at(1), 700., 90., 270.);
+    updateLine (visibleGeometry.at(V_LINE), 700., 90., 270.);
+    updateLine (mouseOverGeometry.at(V_LINE), 700., 90., 270.);
 
     // update upper feather line
-    updateLineWithDecay (visibleGeometry.at(2), 350., 270.);
-    updateLineWithDecay (mouseOverGeometry.at(2), 350., 270.);
+    updateLineWithDecay (visibleGeometry.at(FEATHER_LINE_1), 350., 270.);
+    updateLineWithDecay (mouseOverGeometry.at(FEATHER_LINE_1), 350., 270.);
 
     // update lower feather line
-    updateLineWithDecay (visibleGeometry.at(3), 350., 90.);
-    updateLineWithDecay (mouseOverGeometry.at(3), 350., 90.);
+    updateLineWithDecay (visibleGeometry.at(FEATHER_LINE_2), 350., 90.);
+    updateLineWithDecay (mouseOverGeometry.at(FEATHER_LINE_2), 350., 90.);
 
     // update circle's position
-    updateCircle (visibleGeometry.at(4));
-    updateCircle (mouseOverGeometry.at(4));
+    updateCircle (visibleGeometry.at(CENTER_CIRCLE));
+    updateCircle (mouseOverGeometry.at(CENTER_CIRCLE));
 }
 
 void Gradient::write (ProcParams* pp, ParamsEdited* pedited)
@@ -325,6 +333,7 @@ void Gradient::editToggled ()
     if (edit->get_active()) {
         subscribe();
     } else {
+        releaseEdit();
         unsubscribe();
     }
 }
@@ -332,12 +341,12 @@ void Gradient::editToggled ()
 CursorShape Gradient::getCursor(int objectID, int xPos, int yPos) const
 {
     switch (objectID) {
-    case (0):
-    case (1):
+    case (H_LINE):
+    case (V_LINE):
         return CSMoveRotate;
 
-    case (2):
-    case (3): {
+    case (FEATHER_LINE_1):
+    case (FEATHER_LINE_2): {
         int angle = degree->getIntValue();
 
         if (angle < -135 || (angle >= -45 && angle <= 45) || angle > 135) {
@@ -347,7 +356,7 @@ CursorShape Gradient::getCursor(int objectID, int xPos, int yPos) const
         return CSMove1DH;
     }
 
-    case (4):
+    case (CENTER_CIRCLE):
         return CSMove2D;
 
     default:
@@ -361,18 +370,18 @@ bool Gradient::mouseOver(int modifierKey)
 
     if (editProvider && editProvider->getObject() != lastObject) {
         if (lastObject > -1) {
-            if (lastObject == 2 || lastObject == 3) {
-                EditSubscriber::visibleGeometry.at(2)->state = Geometry::NORMAL;
-                EditSubscriber::visibleGeometry.at(3)->state = Geometry::NORMAL;
+            if (lastObject == FEATHER_LINE_1 || lastObject == FEATHER_LINE_2) {
+                EditSubscriber::visibleGeometry.at(FEATHER_LINE_1)->state = Geometry::NORMAL;
+                EditSubscriber::visibleGeometry.at(FEATHER_LINE_2)->state = Geometry::NORMAL;
             } else {
                 EditSubscriber::visibleGeometry.at(lastObject)->state = Geometry::NORMAL;
             }
         }
 
         if (editProvider->getObject() > -1) {
-            if (editProvider->getObject() == 2 || editProvider->getObject() == 3) {
-                EditSubscriber::visibleGeometry.at(2)->state = Geometry::PRELIGHT;
-                EditSubscriber::visibleGeometry.at(3)->state = Geometry::PRELIGHT;
+            if (editProvider->getObject() == FEATHER_LINE_1 || editProvider->getObject() == FEATHER_LINE_2) {
+                EditSubscriber::visibleGeometry.at(FEATHER_LINE_1)->state = Geometry::PRELIGHT;
+                EditSubscriber::visibleGeometry.at(FEATHER_LINE_2)->state = Geometry::PRELIGHT;
             } else {
                 EditSubscriber::visibleGeometry.at(editProvider->getObject())->state = Geometry::PRELIGHT;
             }
@@ -414,7 +423,7 @@ bool Gradient::button1Pressed(int modifierKey)
         //printf("\ndraggedPointOldAngle=%.3f\n\n", draggedPointOldAngle);
         draggedPointAdjusterAngle = degree->getValue();
 
-        if (lastObject == 2 || lastObject == 3) {
+        if (lastObject == FEATHER_LINE_1 || lastObject == FEATHER_LINE_2) {
             // Dragging a line to change the angle
             PolarCoord draggedPoint;
             rtengine::Coord currPos;
@@ -430,7 +439,7 @@ bool Gradient::button1Pressed(int modifierKey)
             // compute the projected value of the dragged point
             draggedFeatherOffset = draggedPoint.radius * sin((draggedPoint.angle - degree->getValue()) / 180.*rtengine::RT_PI);
 
-            if (lastObject == 3) {
+            if (lastObject == FEATHER_LINE_2) {
                 draggedFeatherOffset = -draggedFeatherOffset;
             }
 
@@ -441,9 +450,9 @@ bool Gradient::button1Pressed(int modifierKey)
         return false;
     } else { // should theoretically always be true
         // this will let this class ignore further drag events
-        if (lastObject == 2 || lastObject == 3) {
-            EditSubscriber::visibleGeometry.at(2)->state = Geometry::NORMAL;
-            EditSubscriber::visibleGeometry.at(3)->state = Geometry::NORMAL;
+        if (lastObject == FEATHER_LINE_1 || lastObject == FEATHER_LINE_2) {
+            EditSubscriber::visibleGeometry.at(FEATHER_LINE_1)->state = Geometry::NORMAL;
+            EditSubscriber::visibleGeometry.at(FEATHER_LINE_2)->state = Geometry::NORMAL;
         } else {
             EditSubscriber::visibleGeometry.at(lastObject)->state = Geometry::NORMAL;
         }
@@ -471,7 +480,7 @@ bool Gradient::drag1(int modifierKey)
     double halfSizeW = imW / 2.;
     double halfSizeH = imH / 2.;
 
-    if (lastObject == 0 || lastObject == 1) {
+    if (lastObject == H_LINE || lastObject == V_LINE) {
 
         // Dragging a line to change the angle
         PolarCoord draggedPoint;
@@ -515,7 +524,7 @@ bool Gradient::drag1(int modifierKey)
 
             return true;
         }
-    } else if (lastObject == 2 || lastObject == 3) {
+    } else if (lastObject == FEATHER_LINE_1 || lastObject == FEATHER_LINE_2) {
         // Dragging the upper or lower feather bar
         PolarCoord draggedPoint;
         rtengine::Coord currPos;
@@ -532,11 +541,11 @@ bool Gradient::drag1(int modifierKey)
         draggedPoint = currPos - centerPos;
         double currDraggedFeatherOffset = draggedPoint.radius * sin((draggedPoint.angle - degree->getValue()) / 180.*rtengine::RT_PI);
 
-        if (lastObject == 2)
+        if (lastObject == FEATHER_LINE_1)
             // Dragging the upper feather bar
         {
             currDraggedFeatherOffset -= draggedFeatherOffset;
-        } else if (lastObject == 3)
+        } else if (lastObject == FEATHER_LINE_2)
             // Dragging the lower feather bar
         {
             currDraggedFeatherOffset = -currDraggedFeatherOffset + draggedFeatherOffset;
@@ -554,7 +563,7 @@ bool Gradient::drag1(int modifierKey)
 
             return true;
         }
-    } else if (lastObject == 4) {
+    } else if (lastObject == CENTER_CIRCLE) {
         // Dragging the circle to change the center
         rtengine::Coord currPos;
         draggedCenter += provider->deltaPrevImage;
@@ -579,6 +588,19 @@ bool Gradient::drag1(int modifierKey)
     return false;
 }
 
+void Gradient::releaseEdit()
+{
+    if (lastObject >= 0) {
+        if (lastObject == FEATHER_LINE_1 || lastObject == FEATHER_LINE_2) {
+            EditSubscriber::visibleGeometry.at(FEATHER_LINE_1)->state = Geometry::NORMAL;
+            EditSubscriber::visibleGeometry.at(FEATHER_LINE_2)->state = Geometry::NORMAL;
+        } else {
+            EditSubscriber::visibleGeometry.at(lastObject)->state = Geometry::NORMAL;
+        }
+    }
+    action = Action::NONE;
+}
+
 void Gradient::switchOffEditMode ()
 {
     if (edit->get_active()) {
diff --git a/rtgui/gradient.h b/rtgui/gradient.h
index 139b281a8..dc0371932 100644
--- a/rtgui/gradient.h
+++ b/rtgui/gradient.h
@@ -35,6 +35,7 @@ protected:
     sigc::connection editConn;
 
     void editToggled ();
+    void releaseEdit();
 
 public:
 
diff --git a/rtgui/perspective.cc b/rtgui/perspective.cc
index 8db91ee2e..fb4797ae4 100644
--- a/rtgui/perspective.cc
+++ b/rtgui/perspective.cc
@@ -778,6 +778,7 @@ void PerspCorrection::linesEditButtonPressed(void)
             listener->unsetTweakOperator(this);
             listener->refreshPreview(EvPerspRender);
         }
+        lines->releaseEdit();
         lines->setDrawMode(false);
         lines->setActive(false);
         if (panel_listener) {
diff --git a/rtgui/spot.cc b/rtgui/spot.cc
index 322ffe106..d9a6be6b7 100644
--- a/rtgui/spot.cc
+++ b/rtgui/spot.cc
@@ -29,8 +29,23 @@
 using namespace rtengine;
 using namespace rtengine::procparams;
 
-#define STATIC_VISIBLE_OBJ_NBR 6
-#define STATIC_MO_OBJ_NBR 6
+enum GeometryIndex {
+    MO_TARGET_DISK,
+    MO_SOURCE_DISC,
+    MO_TARGET_CIRCLE,
+    MO_SOURCE_CIRCLE,
+    MO_TARGET_FEATHER_CIRCLE,
+    MO_SOURCE_FEATHER_CIRCLE,
+    MO_OBJECT_COUNT,
+
+    VISIBLE_SOURCE_ICON = 0,
+    VISIBLE_SOURCE_FEATHER_CIRCLE,
+    VISIBLE_LINK,
+    VISIBLE_SOURCE_CIRCLE,
+    VISIBLE_TARGET_FEATHER_CIRCLE,
+    VISIBLE_TARGET_CIRCLE,
+    VISIBLE_OBJECT_COUNT
+};
 
 Spot::Spot() :
     FoldableToolPanel(this, "spot", M ("TP_SPOT_LABEL"), true, true),
@@ -106,7 +121,7 @@ Spot::~Spot()
 {
     // delete all dynamically allocated geometry
     if (EditSubscriber::visibleGeometry.size()) {
-        for (size_t i = 0; i < EditSubscriber::visibleGeometry.size() - STATIC_VISIBLE_OBJ_NBR; ++i) { // static visible geometry at the end if the list
+        for (size_t i = 0; i < EditSubscriber::visibleGeometry.size() - VISIBLE_OBJECT_COUNT; ++i) { // static visible geometry at the end of the list
             delete EditSubscriber::visibleGeometry.at (i);
         }
     }
@@ -172,6 +187,7 @@ void Spot::resetPressed()
         }
     } else {
         if (!spots.empty()) {
+            EditSubscriber::action = EditSubscriber::Action::NONE;
             spots.clear();
             activeSpot = -1;
             lastObject = -1;
@@ -185,6 +201,25 @@ void Spot::resetPressed()
     }
 }
 
+/**
+ * Release anything that's currently being dragged.
+ */
+void Spot::releaseEdit()
+{
+    Geometry *loGeom = getVisibleGeometryFromMO (lastObject);
+
+    EditSubscriber::action = EditSubscriber::Action::NONE;
+
+    if (!loGeom) {
+        return;
+    }
+
+    loGeom->state = Geometry::NORMAL;
+    sourceIcon.state = Geometry::NORMAL;
+    draggedSide = DraggedSide::NONE;
+    updateGeometry();
+}
+
 void Spot::setBatchMode (bool batchMode)
 {
     ToolPanel::setBatchMode (batchMode);
@@ -237,6 +272,7 @@ void Spot::editToggled ()
             listener->refreshPreview(EvSpotEnabledOPA); // reprocess the preview w/o creating History entry
             subscribe();
         } else {
+            releaseEdit();
             unsubscribe();
             listener->unsetTweakOperator(this);
             listener->refreshPreview(EvSpotEnabled); // reprocess the preview w/o creating History entry
@@ -250,16 +286,16 @@ Geometry* Spot::getVisibleGeometryFromMO (int MOID)
         return nullptr;
     }
 
-    if (MOID == 0) {
+    if (MOID == MO_TARGET_DISK) {
         return getActiveSpotIcon();
     }
 
-    if (MOID == 1) { // sourceMODisc
+    if (MOID == MO_SOURCE_DISC) {
         return &sourceIcon;
     }
 
-    if (MOID > STATIC_MO_OBJ_NBR) {
-        return EditSubscriber::visibleGeometry.at(MOID - STATIC_MO_OBJ_NBR);
+    if (MOID > MO_OBJECT_COUNT) {
+        return EditSubscriber::visibleGeometry.at(MOID - MO_OBJECT_COUNT);
     }
 
     return EditSubscriber::mouseOverGeometry.at (MOID);
@@ -275,30 +311,36 @@ void Spot::createGeometry ()
 
     //printf("CreateGeometry(%d)\n", nbrEntry);
     // delete all dynamically allocated geometry
-    if (EditSubscriber::visibleGeometry.size() > STATIC_VISIBLE_OBJ_NBR)
-        for (size_t i = 0; i < EditSubscriber::visibleGeometry.size() - STATIC_VISIBLE_OBJ_NBR; ++i) { // static visible geometry at the end if the list
+    if (EditSubscriber::visibleGeometry.size() > VISIBLE_OBJECT_COUNT)
+        for (size_t i = 0; i < EditSubscriber::visibleGeometry.size() - VISIBLE_OBJECT_COUNT; ++i) { // static visible geometry at the end of the list
             delete EditSubscriber::visibleGeometry.at (i);
         }
 
     // mouse over geometry starts with the static geometry, then the spot's icon geometry
-    EditSubscriber::mouseOverGeometry.resize (STATIC_MO_OBJ_NBR + nbrEntry);
+    EditSubscriber::mouseOverGeometry.resize (MO_OBJECT_COUNT + nbrEntry);
     // visible geometry starts with the spot's icon geometry, then the static geometry
-    EditSubscriber::visibleGeometry.resize (nbrEntry + STATIC_VISIBLE_OBJ_NBR);
+    EditSubscriber::visibleGeometry.resize (nbrEntry + VISIBLE_OBJECT_COUNT);
 
     size_t i = 0, j = 0;
-    EditSubscriber::mouseOverGeometry.at (i++) = &targetMODisc;        // STATIC_MO_OBJ_NBR + 0
-    EditSubscriber::mouseOverGeometry.at (i++) = &sourceMODisc;        // STATIC_MO_OBJ_NBR + 1
-    EditSubscriber::mouseOverGeometry.at (i++) = &targetCircle;        // STATIC_MO_OBJ_NBR + 2
-    EditSubscriber::mouseOverGeometry.at (i++) = &sourceCircle;        // STATIC_MO_OBJ_NBR + 3
-    EditSubscriber::mouseOverGeometry.at (i++) = &targetFeatherCircle; // STATIC_MO_OBJ_NBR + 4
-    EditSubscriber::mouseOverGeometry.at (i++) = &sourceFeatherCircle; // STATIC_MO_OBJ_NBR + 5
+    assert(i == MO_TARGET_DISK);
+    EditSubscriber::mouseOverGeometry.at (i++) = &targetMODisc;        // MO_OBJECT_COUNT + 0
+    assert(i == MO_SOURCE_DISC);
+    EditSubscriber::mouseOverGeometry.at (i++) = &sourceMODisc;        // MO_OBJECT_COUNT + 1
+    assert(i == MO_TARGET_CIRCLE);
+    EditSubscriber::mouseOverGeometry.at (i++) = &targetCircle;        // MO_OBJECT_COUNT + 2
+    assert(i == MO_SOURCE_CIRCLE);
+    EditSubscriber::mouseOverGeometry.at (i++) = &sourceCircle;        // MO_OBJECT_COUNT + 3
+    assert(i == MO_TARGET_FEATHER_CIRCLE);
+    EditSubscriber::mouseOverGeometry.at (i++) = &targetFeatherCircle; // MO_OBJECT_COUNT + 4
+    assert(i == MO_SOURCE_FEATHER_CIRCLE);
+    EditSubscriber::mouseOverGeometry.at (i++) = &sourceFeatherCircle; // MO_OBJECT_COUNT + 5
 
     // recreate all spots geometry
     Cairo::RefPtr<RTSurface> normalImg   = sourceIcon.getNormalImg();
     Cairo::RefPtr<RTSurface> prelightImg = sourceIcon.getPrelightImg();
     Cairo::RefPtr<RTSurface> activeImg   = sourceIcon.getActiveImg();
 
-    for (; j < EditSubscriber::visibleGeometry.size() - STATIC_VISIBLE_OBJ_NBR; ++i, ++j) {
+    for (; j < EditSubscriber::visibleGeometry.size() - VISIBLE_OBJECT_COUNT; ++i, ++j) {
         EditSubscriber::mouseOverGeometry.at (i) = EditSubscriber::visibleGeometry.at (j) = new OPIcon (normalImg, activeImg, prelightImg, Cairo::RefPtr<RTSurface> (nullptr), Cairo::RefPtr<RTSurface> (nullptr), Geometry::DP_CENTERCENTER);
         EditSubscriber::visibleGeometry.at (j)->setActive (true);
         EditSubscriber::visibleGeometry.at (j)->datum = Geometry::IMAGE;
@@ -306,12 +348,19 @@ void Spot::createGeometry ()
         //printf("mouseOverGeometry.at(%d) = %p\n", (unsigned int)i, (void*)EditSubscriber::mouseOverGeometry.at(i));
     }
 
-    EditSubscriber::visibleGeometry.at (j++) = &sourceIcon;          // STATIC_VISIBLE_OBJ_NBR + 0
-    EditSubscriber::visibleGeometry.at (j++) = &sourceFeatherCircle; // STATIC_VISIBLE_OBJ_NBR + 1
-    EditSubscriber::visibleGeometry.at (j++) = &link;                // STATIC_VISIBLE_OBJ_NBR + 2
-    EditSubscriber::visibleGeometry.at (j++) = &sourceCircle;        // STATIC_VISIBLE_OBJ_NBR + 3
-    EditSubscriber::visibleGeometry.at (j++) = &targetFeatherCircle; // STATIC_VISIBLE_OBJ_NBR + 4
-    EditSubscriber::visibleGeometry.at (j++) = &targetCircle;        // STATIC_VISIBLE_OBJ_NBR + 5
+    int visibleOffset = j;
+    assert(j - visibleOffset == VISIBLE_SOURCE_ICON);
+    EditSubscriber::visibleGeometry.at (j++) = &sourceIcon;          // VISIBLE_OBJECT_COUNT + 0
+    assert(j - visibleOffset == VISIBLE_SOURCE_FEATHER_CIRCLE);
+    EditSubscriber::visibleGeometry.at (j++) = &sourceFeatherCircle; // VISIBLE_OBJECT_COUNT + 1
+    assert(j - visibleOffset == VISIBLE_LINK);
+    EditSubscriber::visibleGeometry.at (j++) = &link;                // VISIBLE_OBJECT_COUNT + 2
+    assert(j - visibleOffset == VISIBLE_SOURCE_CIRCLE);
+    EditSubscriber::visibleGeometry.at (j++) = &sourceCircle;        // VISIBLE_OBJECT_COUNT + 3
+    assert(j - visibleOffset == VISIBLE_TARGET_FEATHER_CIRCLE);
+    EditSubscriber::visibleGeometry.at (j++) = &targetFeatherCircle; // VISIBLE_OBJECT_COUNT + 4
+    assert(j - visibleOffset == VISIBLE_TARGET_CIRCLE);
+    EditSubscriber::visibleGeometry.at (j++) = &targetCircle;        // VISIBLE_OBJECT_COUNT + 5
 }
 
 void Spot::updateGeometry()
@@ -419,7 +468,7 @@ void Spot::addNewEntry()
     se.sourcePos = se.targetPos;
     spots.push_back (se); // this make a copy of se ...
     activeSpot = spots.size() - 1;
-    lastObject = 1;
+    lastObject = MO_SOURCE_DISC;
 
     //printf("ActiveSpot = %d\n", activeSpot);
 
@@ -466,11 +515,11 @@ CursorShape Spot::getCursor (int objectID, int xPos, int yPos) const
             return CSEmpty;
         }
 
-        if (objectID == 0 || objectID == 1) {
+        if (objectID == MO_TARGET_DISK || objectID == MO_SOURCE_DISC) {
             return CSMove2D;
         }
-        if (objectID >= 2 && objectID <= 5) {
-            Coord delta(Coord(xPos, yPos) - ((objectID == 3 || objectID == 5) ? spots.at(activeSpot).sourcePos : spots.at(activeSpot).targetPos));
+        if (objectID >= MO_TARGET_CIRCLE && objectID <= MO_SOURCE_FEATHER_CIRCLE) {
+            Coord delta(Coord(xPos, yPos) - ((objectID == MO_SOURCE_CIRCLE || objectID == MO_SOURCE_FEATHER_CIRCLE) ? spots.at(activeSpot).sourcePos : spots.at(activeSpot).targetPos));
             PolarCoord polarPos(delta);
             if (polarPos.angle < 0.) {
                 polarPos.angle += 180.;
@@ -508,19 +557,19 @@ bool Spot::mouseOver (int modifierKey)
         if (editProvider->getObject() > -1) {
             getVisibleGeometryFromMO (editProvider->getObject())->state = Geometry::PRELIGHT;
 
-            if (editProvider->getObject() >= STATIC_MO_OBJ_NBR) {
+            if (editProvider->getObject() >= MO_OBJECT_COUNT) {
                 // a Spot is being edited
                 int oldActiveSpot = activeSpot;
-                activeSpot = editProvider->getObject() - STATIC_MO_OBJ_NBR;
+                activeSpot = editProvider->getObject() - MO_OBJECT_COUNT;
 
                 if (activeSpot != oldActiveSpot) {
                     if (oldActiveSpot > -1) {
                         EditSubscriber::visibleGeometry.at (oldActiveSpot)->state = Geometry::NORMAL;
-                        EditSubscriber::mouseOverGeometry.at (oldActiveSpot + STATIC_MO_OBJ_NBR)->state = Geometry::NORMAL;
+                        EditSubscriber::mouseOverGeometry.at (oldActiveSpot + MO_OBJECT_COUNT)->state = Geometry::NORMAL;
                     }
 
                     EditSubscriber::visibleGeometry.at (activeSpot)->state = Geometry::PRELIGHT;
-                    EditSubscriber::mouseOverGeometry.at (activeSpot + STATIC_MO_OBJ_NBR)->state = Geometry::PRELIGHT;
+                    EditSubscriber::mouseOverGeometry.at (activeSpot + MO_OBJECT_COUNT)->state = Geometry::PRELIGHT;
                     //printf("ActiveSpot = %d (was %d before)\n", activeSpot, oldActiveSpot);
                 }
             }
@@ -529,7 +578,7 @@ bool Spot::mouseOver (int modifierKey)
         lastObject = editProvider->getObject();
 
         if (lastObject > -1 && EditSubscriber::mouseOverGeometry.at (lastObject) == getActiveSpotIcon()) {
-            lastObject = 0;  // targetMODisc
+            lastObject = MO_TARGET_DISK;
         }
 
         updateGeometry();
@@ -546,12 +595,18 @@ bool Spot::button1Pressed (int modifierKey)
 
     if (editProvider) {
         if (lastObject == -1 && (modifierKey & GDK_CONTROL_MASK)) {
+            int imW, imH;
+            const auto startPos = editProvider->posImage;
+            editProvider->getImageSize(imW, imH);
+            if (startPos.x < 0 || startPos.y < 0 || startPos.x > imW || startPos.y > imH) {
+                return false; // Outside of image area.
+            }
             draggedSide = DraggedSide::SOURCE;
             addNewEntry();
             EditSubscriber::action = EditSubscriber::Action::DRAGGING;
             return true;
         } else if (lastObject > -1) {
-            draggedSide = lastObject == 0 ? DraggedSide::TARGET : lastObject == 1 ? DraggedSide::SOURCE : DraggedSide::NONE;
+            draggedSide = lastObject == MO_TARGET_DISK ? DraggedSide::TARGET : lastObject == MO_SOURCE_DISC ? DraggedSide::SOURCE : DraggedSide::NONE;
             getVisibleGeometryFromMO (lastObject)->state = Geometry::DRAGGED;
             EditSubscriber::action = EditSubscriber::Action::DRAGGING;
             return true;
@@ -603,8 +658,8 @@ bool Spot::button3Pressed (int modifierKey)
         return false;
     }
 
-    if ((modifierKey & GDK_CONTROL_MASK) && (EditSubscriber::mouseOverGeometry.at (lastObject) == &targetMODisc || lastObject >= STATIC_MO_OBJ_NBR)) {
-        lastObject = 1;  // sourceMODisc
+    if ((modifierKey & GDK_CONTROL_MASK) && (EditSubscriber::mouseOverGeometry.at (lastObject) == &targetMODisc || lastObject >= MO_OBJECT_COUNT)) {
+        lastObject = MO_SOURCE_DISC;
         sourceIcon.state = Geometry::DRAGGED;
         EditSubscriber::action = EditSubscriber::Action::DRAGGING;
         draggedSide = DraggedSide::SOURCE;
@@ -631,12 +686,14 @@ bool Spot::button3Released()
     updateGeometry();
     EditSubscriber::action = EditSubscriber::Action::NONE;
     return true;
-
-    return false;
 }
 
 bool Spot::drag1 (int modifierKey)
 {
+    if (EditSubscriber::action != EditSubscriber::Action::DRAGGING) {
+        return false;
+    }
+
     EditDataProvider *editProvider = getEditProvider();
     int imW, imH;
     editProvider->getImageSize (imW, imH);
@@ -656,8 +713,8 @@ bool Spot::drag1 (int modifierKey)
             modified = true;
         }
 
-        EditSubscriber::mouseOverGeometry.at (activeSpot + STATIC_MO_OBJ_NBR)->state = Geometry::DRAGGED;
-    } else if (loGeom == &targetMODisc || lastObject >= STATIC_MO_OBJ_NBR) {
+        EditSubscriber::mouseOverGeometry.at (activeSpot + MO_OBJECT_COUNT)->state = Geometry::DRAGGED;
+    } else if (loGeom == &targetMODisc || lastObject >= MO_OBJECT_COUNT) {
         //printf("targetMODisc / deltaPrevImage = %d / %d\n", editProvider->deltaPrevImage.x, editProvider->deltaPrevImage.y);
         rtengine::Coord currPos = spots.at (activeSpot).targetPos;
         spots.at (activeSpot).targetPos += editProvider->deltaPrevImage;
@@ -718,6 +775,10 @@ bool Spot::drag1 (int modifierKey)
 
 bool Spot::drag3 (int modifierKey)
 {
+    if (EditSubscriber::action != EditSubscriber::Action::DRAGGING) {
+        return false;
+    }
+
     EditDataProvider *editProvider = getEditProvider();
     int imW, imH;
     editProvider->getImageSize (imW, imH);
diff --git a/rtgui/spot.h b/rtgui/spot.h
index db1fdac05..85cefa4c2 100644
--- a/rtgui/spot.h
+++ b/rtgui/spot.h
@@ -82,6 +82,7 @@ private:
     void addNewEntry ();
     void deleteSelectedEntry ();
     void resetPressed ();
+    void releaseEdit();
 
 protected:
     Gtk::Box* labelBox;