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Molkit

How Projections Work

Molkit’s projections (Fischer, Newman, Haworth, and chair) are not pictures. Each one is a set of real atoms and bonds in your document, linked to a projection annotation that renders them in the projection’s visual style. The annotation stores which atoms play which roles (chiral centers, front and back carbons, ring positions) and draws the canonical geometry from their live positions. Everything else about the atoms stays ordinary: they select, move, count, and export like any other atoms.

Creating a projection

Click the Projection button in the toolbar to open its flyout (press J to activate the tool from the keyboard). The flyout offers Fischer with 1 to 4 chiral centers, Newman in staggered, eclipsed, anti, and gauche variants, Haworth pyranose and furanose rings, and standard or flipped chairs. Pick a variant, then click the canvas to place it. The new projection arrives selected and the active tool switches to Select so you can adjust it right away.

Prefilled projections such as D-glucose in Fischer or Haworth form are also available in the template browser.

What all projection types share

  • Selection. You select a projection through its atoms, not as a separate object. Double-clicking an unselected atom with the Select tool selects the whole connected structure (double-clicking an already-selected atom opens its label editor instead). Select All also reaches projections through their atoms.
  • Moving. Drag the selected atoms and the projection moves with them. The renderer reads live atom positions, so the drawing always follows the atoms.
  • Projection Properties panel. Selecting a projection atom opens a docked panel on the right with settings for that projection type, such as spacing and arm length for Fischer or circle radius and bond length for Newman. Edits re-derive the affected atoms.
  • Substituent editing. Double-click a substituent position to open the label editor and type a new group. Simple symbols like OH become real atoms of that element; compound labels like CHO are stored as a single carbon carrying the text.
  • Per-type pages. Each projection type has its own page covering its specific handles and settings, linked below.

Chemistry tools see projections

Because projection atoms are real, the formula and molecular weight readout includes them when they are selected, and SMILES export walks the same atom and bond graph. One caveat: a compound substituent label is one carbon atom with display text, so calculations count one carbon there rather than the full group.

Erasing a projection

The eraser works on individual projection atoms. Erasing a structural atom (a Fischer chiral center, a Newman front or back carbon, or a Haworth or chair ring atom) removes the whole projection annotation; any surviving atoms remain on the canvas as an ordinary structure. Erasing a substituent atom only removes that atom and clears its slot. To delete a projection completely, double-click it to select all of its atoms and press Delete.

See also