fix(dynmode): one toggle keeps DYNMODE's sign in step

F12, the drafting dialog and restored settings each re-derived DYNMODE and
lost the mode on the way: F12 off set 0, so on came back as 3 even after
DYNMODE 1. set_dyn_input now makes off negative (temporarily off) and on
restore the stored mode, and the bare query prints the stored value.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/app/commands/styleprops.rs

@@ -1713,14 +1713,7 @@ impl OpenCADStudio {
                                     }
                                     _ => Err("SETVAR: integer from -3 to 3 required.".into()),
                                 },
-                                None => {
-                                    let mode = if self.dyn_input {
-                                        if self.dyn_mode > 0 { self.dyn_mode } else { 3 }
-                                    } else {
-                                        if self.dyn_mode <= 0 { self.dyn_mode } else { 0 }
-                                    };
-                                    Ok((format!("DYNMODE = {mode}"), false))
-                                }
+                                None => Ok((format!("DYNMODE = {}", self.dyn_mode), false)),
                             },
                             "ZOOMWHEEL" => match &value {
                                 Some(v) => match parse_bool(v) {
@@ -3838,14 +3831,14 @@ mod tests {
         assert_eq!(app.dyn_mode, 1);
         assert!(app.dyn_input);
 
-        // F12 / Message::ToggleDynInput synchronization
+        // F12 turns it off temporarily (negative) and restores the mode.
         let _ = app.update(crate::app::Message::ToggleDynInput);
         assert!(!app.dyn_input);
-        assert_eq!(app.dyn_mode, 0);
+        assert_eq!(app.dyn_mode, -1);
 
         let _ = app.update(crate::app::Message::ToggleDynInput);
         assert!(app.dyn_input);
-        assert_eq!(app.dyn_mode, 3);
+        assert_eq!(app.dyn_mode, 1);
     }
 }
 

src/app/drafting_settings.rs

@@ -44,6 +44,18 @@ impl DraftingSettingsState {
 }
 
 impl OpenCADStudio {
+    /// Turn Dynamic Input on or off with DYNMODE in step: off keeps the mode
+    /// negative (temporarily off), on restores it, or 3 when there was none.
+    pub(in crate::app) fn set_dyn_input(&mut self, on: bool) {
+        self.dyn_input = on;
+        let mode = self.dyn_mode.abs();
+        self.dyn_mode = match (on, mode) {
+            (true, 0) => 3,
+            (true, mode) => mode,
+            (false, mode) => -mode,
+        };
+    }
+
     pub(super) fn drafting_settings_dirty(&self) -> bool {
         match (&self.drafting_settings_state, &self.drafting_settings_saved) {
             (Some(curr), Some(saved)) => curr.is_dirty(saved),
@@ -100,12 +112,7 @@ impl OpenCADStudio {
         self.snapper.enabled = state.snap_modes.clone();
         self.snapper.snap3d_enabled = state.osnap3d_on;
         self.snapper.enabled3d = state.snap3d_modes.clone();
-        self.dyn_input = state.dyn_input_on;
-        if self.dyn_input && self.dyn_mode <= 0 {
-            self.dyn_mode = 3;
-        } else if !self.dyn_input && self.dyn_mode > 0 {
-            self.dyn_mode = 0;
-        }
+        self.set_dyn_input(state.dyn_input_on);
         self.quick_properties = state.quick_props_on;
         self.selection_cycling = state.selection_cycling_on;
         self.sync_vport_display(self.active_tab);

src/app/update/file.rs

@@ -750,8 +750,8 @@ impl OpenCADStudio {
 
     /// Apply restored preferences to live state.
     pub(in crate::app) fn apply_settings(&mut self, s: &crate::app::settings::UserSettings) {
-        self.dyn_input = s.dyn_input;
-        self.dyn_mode = if s.dyn_mode != 0 { s.dyn_mode } else if s.dyn_input { 3 } else { 0 };
+        self.dyn_mode = s.dyn_mode;
+        self.set_dyn_input(s.dyn_input);
         self.polar_mode = s.polar;
         self.polar_increment_deg = s.polar_increment_deg;
         self.zoom_wheel_reversed = s.zoom_wheel_reversed;

src/app/update/mod.rs

@@ -4196,12 +4196,7 @@ impl OpenCADStudio {
                 Task::none()
             }
             Message::ToggleDynInput => {
-                self.dyn_input ^= true;
-                if self.dyn_input && self.dyn_mode <= 0 {
-                    self.dyn_mode = 3;
-                } else if !self.dyn_input && self.dyn_mode > 0 {
-                    self.dyn_mode = 0;
-                }
+                self.set_dyn_input(!self.dyn_input);
                 Task::none()
             }
             Message::ToggleViewCube => {