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Editing Shapes

Everything here happens with the Select tool (V).

  • Click a shape to select it. The selection is rendered on top and shows its control points.
  • Drag on empty canvas to box-select multiple objects.
  • Ctrl+A selects all annotations on the image.
  • Clicking empty canvas or pressing Esc clears the selection.
  • Drag a selected shape to move it.
  • Drag one of the control points to resize; the cursor and a hover highlight indicate the grabbable handle.
  • Pinned objects refuse to move — pin anything you must not nudge by accident (see per-object states).

Rectangles and ellipses expose a rotation handle; drag it to rotate the shape around its center. The angle is stored per shape (rotation_deg in the data format).

Double-click a polygon or polyline to enter vertex-editing mode — every vertex becomes a draggable handle:

Action How
Move a vertex drag it
Insert a vertex click on an edge
Delete a vertex Alt+click it
Append vertices Shift+click the shape, then click to add
Leave the mode Esc

Right-click a shape for object operations — deletion, vertex operations and more — without leaving the canvas.

  • Ctrl+C / Ctrl+V copy and paste annotations.
  • Delete (or Backspace) removes the selection.
  • = brings the selected shape to the front, - sends it to the back — handy when small grains hide under large ones.

G toggles group mode: select several objects and group them so they act as one logical unit. Shift+G resets the grouping of the selected objects.

Each object carries independent flags, toggled in the Objects panel row or by shortcut while selected:

State Shortcut Effect
Locked L can’t be moved or edited
Occluded Q marked as partially hidden; rendered distinctly
Hidden invisible on canvas, still in the data
Pinned position fixed; can’t be dragged

With objects selected, press 10 or Ctrl+10 to assign the corresponding label. With nothing selected, 10 switches the active label for future shapes instead. You can also change a label from the object’s row in the Objects panel.

Every operation on this page is undoable with Ctrl+Z and re-doable with Ctrl+Shift+Z / Ctrl+Y.