czml-time-dynamic-motion

name	czml-time-dynamic-motion
description	CZML time-dynamic motion: interpolated/sampled positions over an epoch and trails for orbiting, flying, or otherwise moving entities. Use when the intent describes an entity moving, orbiting, flying, or changing position over time (not a single static point).

CZML Time-Dynamic Motion

• A moving entity's "position" is sampled, not static: { "epoch": "<ISO8601>", "cartographicDegrees": [t0, lon0, lat0, h0, t1, lon1, lat1, h1, ...] } (or "cartesian" samples — [t0, x0, y0, z0, t1, x1, y1, z1, ...], ECEF meters — if the intent specifically asks for a Cartesian/ECEF position rather than longitude/latitude/height). t0 < t1 < ... are seconds since "epoch". Compute the actual sample values yourself from the intent — never leave placeholder values.
• "availability": "/" — bounds when the entity is active; add this whenever the document packet also carries a "clock" that should bound this entity's lifetime.
• "path": { "material": { "solidColor": { "color": { "rgba": [r,g,b,a] } } }, "width": <number>, "resolution": <seconds>, "leadTime": <seconds>, "trailTime": <seconds>, "materialMode": "WHOLE"|"PORTIONS" } — draws a trail behind a time-dynamic "position". "materialMode" defaults to "WHOLE" (one material for the entire path). Set it to "PORTIONS" when the intent wants the material to change along the path at distinct time intervals; in that case give "material" as an array of interval-scoped materials instead of a single object: "material": [{ "interval": "<ISO8601 start>/<ISO8601 end>", "solidColor": {...} }, { "interval": "<next start>/<next end>", "polylineDash": {...} }].
• This same "epoch" + interleaved-timestamp-and-value-samples pattern also applies to any other time-varying numeric property (e.g. a sampled rotation angle) — not just "position".

Example: a satellite orbit (time-dynamic position + path)

[
  {
    "id": "document",
    "name": "Satellite orbit",
    "version": "1.0",
    "clock": {
      "interval": "2026-01-01T00:00:00Z/2026-01-02T00:00:00Z",
      "currentTime": "2026-01-01T00:00:00Z",
      "multiplier": 60,
      "range": "LOOP_STOP"
    }
  },
  {
    "id": "sat-1",
    "name": "Satellite 1",
    "availability": "2026-01-01T00:00:00Z/2026-01-02T00:00:00Z",
    "position": {
      "epoch": "2026-01-01T00:00:00Z",
      "cartographicDegrees": [0, 0, 0, 500000, 2700, 90, 0, 500000, 5400, 180, 0, 500000]
    },
    "point": { "pixelSize": 8, "color": { "rgba": [255, 255, 0, 255] } },
    "path": {
      "resolution": 120,
      "leadTime": 0,
      "trailTime": 5400,
      "material": { "solidColor": { "color": { "rgba": [255, 255, 0, 128] } } },
      "width": 2
    }
  }
]