Improve scaling behavior

rayforge/doceditor/editor.py

@@ -83,6 +83,9 @@ def __init__(
             self._on_processing_state_changed
         )
 
+        # Global preference for maintaining aspect ratio during transforms.
+        self.aspect_ratio_locked: bool = True
+
         # Instantiate and link command handlers, passing dependencies.
         self.asset = AssetCmd(self)
         self.edit = EditCmd(self)

rayforge/doceditor/ui/item_properties.py

@@ -99,7 +99,7 @@ def __init__(
 
         # Fixed Ratio Switch
         self.fixed_ratio_switch = Adw.SwitchRow(
-            title=_("Fixed Ratio"), active=True
+            title=_("Fixed Ratio"), active=self.editor.aspect_ratio_locked
         )
         self.fixed_ratio_switch.connect(
             "notify::active", self._on_fixed_ratio_toggled
@@ -415,7 +415,10 @@ def _on_shear_changed(self, spin_row, GParamSpec):
             self._in_update = False
 
     def _on_fixed_ratio_toggled(self, switch_row, GParamSpec):
+        if self._in_update:
+            return
         logger.debug(f"Fixed ratio toggled: {switch_row.get_active()}")
+        self.editor.aspect_ratio_locked = switch_row.get_active()
         # Check if the primary selected item is a workpiece or stock item
         is_ratio_lockable = self.items and isinstance(
             self.items[0], (WorkPiece, StockItem, Group)
@@ -705,6 +708,10 @@ def _update_row_visibility_and_details(self, item: DocItem):
             is_single_workpiece or is_single_stockitem or is_single_group
         )
 
+        self._in_update = True
+        self.fixed_ratio_switch.set_active(self.editor.aspect_ratio_locked)
+        self._in_update = False
+
         self.source_file_row.set_visible(is_single_workpiece)
         self.fixed_ratio_switch.set_sensitive(
             is_single_item_with_size or is_single_group

rayforge/workbench/canvas/canvas.py

@@ -12,6 +12,7 @@
 from .region import (
     ElementRegion,
     BBOX_REGIONS,
+    CORNER_RESIZE_HANDLES,
     RESIZE_HANDLES,
     ROTATE_HANDLES,
     ROTATE_SHEAR_HANDLES,
@@ -139,6 +140,23 @@ def find_by_data(self, data: Any) -> Optional[CanvasElement]:
         """
         return self.root.find_by_data(data)
 
+    def _get_ratio_lock_default(self) -> bool:
+        """
+        Base implementation for whether aspect ratio should be locked during
+        resize. Subclasses can override to bind to UI state.
+        """
+        return False
+
+    def _should_constrain_aspect(self, active_region: ElementRegion) -> bool:
+        """
+        Determines if the current resize interaction should maintain aspect
+        ratio, applying Shift as an inverter of the default preference. Only
+        corner handles honor aspect locking; edge handles always deform.
+        """
+        if active_region not in CORNER_RESIZE_HANDLES:
+            return False
+        return self._get_ratio_lock_default() ^ self._shift_pressed
+
     def find_by_type(
         self, thetype: Any
     ) -> Generator[CanvasElement, None, None]:
@@ -863,13 +881,16 @@ def on_mouse_drag(self, gesture, offset_x: float, offset_y: float):
                 self._selection_group.apply_move(world_dx, world_dy)
             elif self._resizing:
                 if self._active_origin:
+                    constrain_aspect = self._should_constrain_aspect(
+                        self._active_region
+                    )
                     self._selection_group.resize_from_drag(
                         self._active_region,
                         world_dx,
                         world_dy,
                         self._active_origin,
                         self._ctrl_pressed,
-                        self._shift_pressed,
+                        constrain_aspect,
                     )
                 for elem in self._selection_group.elements:
                     elem.trigger_update()
@@ -930,6 +951,9 @@ def on_mouse_drag(self, gesture, offset_x: float, offset_y: float):
                     and self._initial_transform
                     and self._initial_world_transform
                 ):
+                    constrain_aspect = self._should_constrain_aspect(
+                        self._active_region
+                    )
                     transform.resize_element(
                         element=self._drag_target,
                         world_dx=world_dx,
@@ -938,7 +962,7 @@ def on_mouse_drag(self, gesture, offset_x: float, offset_y: float):
                         initial_world_transform=self._initial_world_transform,
                         active_region=self._active_region,
                         view_transform=self.view_transform,
-                        shift_pressed=self._shift_pressed,
+                        constrain_aspect=constrain_aspect,
                         ctrl_pressed=self._ctrl_pressed,
                     )
                     self._drag_target.trigger_update()

rayforge/workbench/canvas/multiselect.py

@@ -246,7 +246,7 @@ def resize_from_drag(
         offset_y: float,
         active_origin: Tuple[float, float, float, float],
         ctrl_pressed: bool,
-        shift_pressed: bool,
+        constrain_aspect: bool,
     ):
         """
         Calculates and applies the new group bounding box by calling the
@@ -267,7 +267,7 @@ def resize_from_drag(
             active_region=active_region,
             drag_delta=(offset_x, offset_y),
             is_flipped=self.canvas.view_transform.is_flipped(),
-            constrain_aspect=shift_pressed,
+            constrain_aspect=constrain_aspect,
             from_center=ctrl_pressed,
             min_size=min_size_world,
         )

rayforge/workbench/canvas/transform.py

@@ -129,7 +129,7 @@ def resize_element(
     initial_world_transform: Matrix,
     active_region: ElementRegion,
     view_transform: Matrix,
-    shift_pressed: bool,
+    constrain_aspect: bool,
     ctrl_pressed: bool,
 ):
     """
@@ -156,7 +156,7 @@ def resize_element(
         active_region=active_region,
         drag_delta=local_delta,
         is_flipped=view_transform.is_flipped(),  # Pass the flag
-        constrain_aspect=shift_pressed,
+        constrain_aspect=constrain_aspect,
         from_center=ctrl_pressed,
         min_size=min_size_local,
     )

rayforge/workbench/surface.py

@@ -91,6 +91,11 @@ def __init__(
         self.edit_sketch_requested = Signal()
         self.edit_stock_item_requested = Signal()
 
+        # Aspect-ratio lock preference shared with the properties panel.
+        self.editor.aspect_ratio_locked = (
+            getattr(self.editor, "aspect_ratio_locked", True) is True
+        )
+
         # Connect to generic signals from the base Canvas class
         self.move_begin.connect(self._on_any_transform_begin)
         self.resize_begin.connect(self._on_resize_begin)
@@ -120,6 +125,17 @@ def show_travel_moves(self) -> bool:
         """Returns True if travel moves should be rendered."""
         return self._show_travel_moves
 
+    def _get_ratio_lock_default(self) -> bool:
+        """
+        Returns the current aspect-ratio lock preference shared with the
+        properties panel. Defaults to True for workpieces.
+        """
+        return bool(getattr(self.editor, "aspect_ratio_locked", True))
+
+    def set_aspect_ratio_locked(self, locked: bool) -> None:
+        """Synchronizes the lock state with the editor."""
+        self.editor.aspect_ratio_locked = locked
+
     def set_laser_dot_visible(self, visible: bool = True) -> None:
         self._laser_dot.set_visible(visible)
         self.queue_draw()