Properties Tab

The Properties Tab allows you to view and edit the properties of the currently selected volume.

Overview

When you select a placement in the Geometry Tree or 3D Viewer, the Properties Tab shows two sections:

  1. Volume definition (shared across all placements of this volume) — name, type, material, dimensions
  2. Placement (specific to this instance) — position, rotation, parent volume

Editing a volume-definition field (e.g. dimensions) updates all placements of that volume at once. Editing a placement field only affects the selected instance.

Editable fields

Volume definition (shared)

Field Description
Name Logical volume name
G4 name Geant4 physical volume name (optional)
Type Shape type (read-only after creation)
Material Material name (NIST or custom)
Dimensions Shape-specific parameters (see types below)
Visible Show/hide in 3D view
Wireframe Render as wireframe
Display Group Folder label in the Geometry Tree
Hits Collection Sensitive detector collection name

Placement (per instance)

Field Description
Placement name Name of this G4PVPlacement
Position (x, y, z) Position in mm relative to the parent volume
Rotation (x, y, z) Euler angles in degrees (XYZ convention)
Parent volume Mother volume for this placement

Dimension fields by type

Type Fields
box x, y, z (half-lengths, mm)
cylinder / tube radius, height, innerRadius (optional)
sphere radius, innerRadius, startPhi, deltaPhi, startTheta, deltaTheta
cone rmin1, rmax1, rmin2, rmax2, height
torus rmin, rmax, rtor, startPhi, deltaPhi
trapezoid / trd x1, x2, y1, y2, z
polycone startPhi, deltaPhi, zPlanes (z/rmin/rmax per plane)
ellipsoid xSemiAxis, ySemiAxis, zSemiAxis
assembly (no dimensions — managed via components)
union / subtraction (no dimensions — managed via components)

Real-time updates

Changes in the Properties Tab are applied immediately and reflected in the 3D Viewer. There is no explicit save step — the JSON state updates on each edit.