Panel sizing

The fixed HP width table and fixed 3U panel height, quoted from panel-sizes.ts.

Fixed height

export const PANEL_HEIGHT_MM = 128.5; // 3U Eurorack panel height

Every panel is 128.5 mm tall. There is no per-panel height field anywhere in the document model — height is a product constant, not a layout choice.

HP width table

Panel width is looked up by HP (horizontal pitch) from a fixed spec table, not computed as a simple multiple of the nominal Eurorack pitch. These are the actual product widths from the Takazudo Modular blank-panel spec tables — real panels are undersized versus the nominal HP * 5.08mm for mounting clearance:

packages/core/src/panel-sizes.ts exposes this as PANEL_SIZES: readonly PanelSize[], where PanelSize is { hp: number; widthMm: number }.

Looking up width: panelWidthMm(hp)

function panelWidthMm(hp: number): number {
  const found = PANEL_SIZES.find((s) => s.hp === hp);
  if (found) return found.widthMm;
  return hp * NOMINAL_HP_PITCH_MM;
}

• For an HP present in the table above, this returns the exact measured width.

• For any other HP, it falls back to hp * NOMINAL_HP_PITCH_MM (NOMINAL_HP_PITCH_MM = 5.08), the nominal Eurorack module pitch.