Selection and Editing

Selection and Editing

This page describes selecting objects and molecular fragments, moving them, editing labels, and undoing a change.

Choose the Selection Tool (V) to click an object or drag a region. Dragging a selected object moves it; dragging on blank page selects objects in the region. Lasso Selection (L) draws a free-form selection region; hold Option on macOS or Alt on Windows to subtract. The Eraser Tool (E) deletes an object by clicking it or deletes touched objects with a drag marquee.

Whole objects and fragments

ChemDraft distinguishes an object selection from a molecular fragment selection. A document object—such as a molecule, text object, arrow, or graphic—can be selected as a whole. A lasso or marquee can also select particular atoms and bonds in a molecule. That fragment selection can be copied and cut; it is not falsely represented as selecting the entire molecule.

When you drag a whole object, its placement may magnetically snap. Whole-object rotation snaps to absolute 15° multiples; holding Shift while dragging also constrains it to those multiples. Group rotation uses 15° drag increments. These are geometry operations, not chemistry changes.

Edit commands

Edit > Select All uses Cmd+A on macOS and Ctrl+A on Windows. Cut, Copy, and Paste use the corresponding system modifiers. Delete has two routes: Backspace and Delete delete the current selection or a hovered native atom/bond. For a labeled atom, the first key removes just the label; the next removes the atom. This supports quickly returning a labeled carbon to skeletal display without breaking its bonds.

Undo is Cmd+Z on macOS and Ctrl+Z on Windows. Redo is Shift+Cmd+Z on macOS and Ctrl+Shift+Z on Windows, with Ctrl+Y also bound on Windows. Availability is meaningful: commands which need a selection are disabled until an appropriate selection exists. See Keyboard Shortcuts.

Editing labels and text

Clicking an atom with the Atom Label Tool edits the label. Clicking an atom with the Text Tool opens the same label editor; clicking elsewhere makes a text object. A selected fresh text object on an atom can be converted automatically under the documented placement conditions, while the explicit Convert Text to Atom Label command works within one bond length. Labels have chemistry-aware close behavior; read Atoms and Labels before using abbreviated substituent labels in a crowded structure.

Layers and groups

For selected page objects, ChemDraft provides Group/Ungroup, Bring to Front, Bring Forward, Send Backward, and Send to Back. Alignment and distribution commands are enabled only for the number of selected objects they require: two for alignment, three for distribution. Grouping and ordering change document layout, not molecular connectivity.

A careful editing habit

Select first, then make a command’s scope visible before committing it. Whole-molecule selection and partial molecular selection deliberately have different effects for some operations. If the result is not useful, Undo returns the document history state; it does not attempt a chemistry-changing repair. This makes exploratory editing safer when a page contains both structures and annotations.

Next

• Copy, Paste, and Clipboard
• Toolbars and Palettes
• Documents, Pages, and Tabs