Kml Timeline Type

A Kml Timeline represents an ordered, time-stamped sequence of Kml overlays, assembled into a single animated display for Google Earth: each entry can carry a beginTime/endTime pair so that Google Earth shows and hides it as the timeline plays through those dates.

A Kml Timeline is built entirely through repeated calls to Set Kml Timeline: each call inserts one Kml entry, either starting a fresh timeline (when its kmlTimeline input is left at its default of .none) or appending to an existing one. Mux Kml Timeline carries the growing timeline across the iterations of a loop, the same role Mux Map and Mux Lookup Table play for their own types – though since Kml Timeline has no generic carrier functor (unlike Kml or Map), the initial value fed into it must itself come from a Set Kml Timeline call made before the loop starts. Nothing else in the functor catalog consumes a Kml Timeline: notably, Save Compressed Kml accepts only a plain Kml, and no automatic conversion is registered between the two types.

Input ports of type Kml Timeline are non-editable, so a Kml Timeline value cannot be defined using an editor in the graphical interface. A Kml Timeline value must always come from connecting an output produced by another functor – Set Kml Timeline or Mux Kml Timeline – supplied by wiring that output to the input.

For the same reason, input ports of type Kml Timeline cannot receive a constant in EGO Script – see Constants. Unlike Kml, there is no generic carrier functor for Kml Timeline either; a Kml Timeline is always obtained directly from Set Kml Timeline or Mux Kml Timeline, and reused by referencing the variable bound to its output:

// landUse2020 and landUse2021 are Categorical Maps loaded earlier in the model.
// The first call starts a fresh Kml Timeline (kmlTimeline defaults to .none);
// the second call appends to the timeline the first call produced.
overlay2020 := CreateKml landUse2020;
overlay2021 := CreateKml landUse2021;

timeline1 := SetKmlTimeline overlay2020;
timeline2 := SetKmlTimeline overlay2021 timeline1;

Building a timeline across a loop instead of a fixed sequence of calls follows the general mux pattern: Mux Kml Timeline at the top of the loop body, paired with a Set Kml Timeline call at the bottom that feeds its result back in as the next iteration's feedback input.

Kml Timeline Type has no registered conversions to or from any other type. The only conversion registered for it at all is the sequencing conversion to None Type – used to force execution order via sequenceInput/sequenceOutput ports, not to transform a value.

See Type System.