Form-Function Diagram Creator
Draw the formal functions of a movement or theme as a row of labelled shapes. Every measure has the same width, so each shape's length shows its proportion of the music, and the measure-number bar is a true ruler. When a shape is too short for its label, the name is abbreviated (Pres., Cont., Cad.…) and the measure numbers get smaller. Only if that still doesn't fit does the whole diagram widen.
Example: CS 1.2, an exposition sketch for the Eroica's first movement (Posen, Figure 30).
Using the editor
- Add shapes. Drag a shape from the left panel into a row, or click it to add it after the selected shape. Drop below the last row to start a new row.
- Edit in the inspector. Select a shape, then type its name and its start and end measures. The label becomes e.g. MT (1–15). By default, changing a shape's length shifts the measure numbers of the shapes after it.
- Annotate. Add a cadence (PAC, HC…), a key (E-flat:), or a melody icon. A measure-number bar under each row marks where every shape begins and ends.
- Group parts. ⇧-click consecutive shapes and choose Bracket as multi-part theme, or drag the bracket onto the first part.
- Keep it. Your work saves automatically in this browser. Use Save for a file, Copy link to share an editable copy, or Export for SVG/PNG.
The shapes
- Theme
- Rounded rectangle: a theme that closes with a perfect authentic cadence. The parts of a theme with multiple parts have dashed borders and a labelled line above them.
- Transition
- Arrow shape. Non-modulating transitions are level. A modulating transition is rotated 15° counterclockwise (sharp direction, "up") or clockwise (flat direction, "down"), and the shapes after it move up or down to match.
- Standing on the dominant
- Lines above and below the label: a static dominant prolongation.
- Closing section
- Vertical lines on both sides: an "after the end" function.
- Sentential functions
- Initiating (square left, curved right), continuation (curved both sides), cadential (curved left, square right): beginning, middle and end.
- Development functions
- Following Caplin: the pre-core is a wedge that widens into the core. A core's model is a plain rectangle, each sequence a dashed copy one step lower (descending) or higher (ascending), and fragmentation a continuation shape whose tick marks shrink. A bracket with end ticks labels the core.
- Period functions
- Rectangles; the dotted edge between antecedent and consequent shows that they depend on each other. Compound functions use the same shapes, elongated.
Shape vocabulary from Thomas Posen, Analyzing Beethoven's Eroica Sketches: A Form-Functional Perspective on the First-Movement Exposition, §2.2, with some new shapes created for development functions. Function names follow William E. Caplin, Analyzing Classical Form: An Approach for the Classroom (Oxford, 2013). Set in EB Garamond (SIL Open Font License).