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Field viewer and ringdown

The Field Viewer shows what the FDTD solver actually computed in 3D. The toolbar has two top-level modes: Surface Currents and E/H Fields. Each mode has its own colour map, geometry overlay, and a Domain switch between Frequency and Time.

Surface Currents

Per-conductor surface current magnitude on every conductor primitive. Useful for spotting where the antenna is actually radiating from, versus where copper is doing nothing.

Enable by checking Save Surface Currents on the Simulate tab before the run. The setting persists on the project.

  • Cmap. Colour map. Defaults to Inferno. Viridis, Turbo, Plasma, Hot, Jet, and others are in the dropdown.
  • Range. Global uses a consistent scale across every frequency or frame, which is the right choice when comparing magnitudes. Per-frame autoscales each frame.
  • Geometry. Overlay toggle and opacity slider.
  • Domain. Switch between the per-frequency frequency-domain view and the time-domain animation.

Picking a different colour map only changes the rendering, not the underlying values. The example below is the same Surface Currents view as above, switched to Viridis:

Time-domain mode

Switching Domain to Time swaps the frequency selector for a frame slider over the captured time steps. The status line shows the current frame, total frame count, and the simulated picoseconds elapsed. Press Play to animate. Playback is capped at 30 frames per second so the GPU stays responsive.

3D E/H Fields

Click E/H Fields in the toolbar for the volumetric view. The viewer renders the electric field magnitude |E| as a 3D cloud around the geometry. A magnetic field mode is planned and the menu label is named ahead of it. Until that ships, every value on screen is |E|. Use this view to see how the field decays away from the radiator and to confirm the PML is absorbing rather than reflecting.

In Time mode, the volumetric view shows the propagating wavefront moving outward from the source as the animation plays.

Full-field export is opt-in and expensive
The dense volumetric field is what feeds 3D E/H Fields. Output ranges from hundreds of megabytes to several gigabytes per simulation. The toggle lives under Simulate, then Advanced mode, then Export full fields (expensive!). Auto mode does not write the volumetric field by default. Switch to Advanced if you need it.

Empty state

Before a run finishes, or when the relevant Simulate-tab option was not enabled, each Field Viewer mode shows an explicit empty state telling you which option to flip on. The same shape applies to the Radiation Pattern empty state.