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Capacity Surface

At low zoom GIPS draws a capacity surface: a colored raster, interpolated in the browser from the scenario already loaded, that answers the question a reader brings to a whole-territory view — roughly where is there capacity? — before handing off to clusters and then to individual POI markers as you zoom in.

New in v4.0.0

There is nothing to configure. The surface is drawn from the deployment's own ranges, so fitting ranges to a study fits the surface to it.

How it is drawn​

  • Each pixel is colored by the best site within a 40 km support radius.
  • A second channel — an agreement stipple — shows how many of the POIs in reach share that reading. A neighborhood where nothing has headroom draws solid, there being no positive claim to qualify.
  • Coincident POIs collapse into a single site before the interpolation runs, so a substation carrying dozens of buses on one coordinate does not outweigh a genuinely well-supplied region several counties wide.
  • The surface sits directly beneath the POI markers and over everything below them — the basemap's land and water shading, roads, boundaries and labels, and the power infrastructure and data layers. What it covers is therefore the same at every zoom, and the same on Aerial as on Streets.

Switching it on and off​

The surface has no switch of its own. The Visible checkbox above the POI table shows and hides the surface and the POI markers together — they are one dataset seen two ways. The legend keeps a Capacity surface section naming the two swatches specific to it.

Clicking the surface​

Clicking a colored pixel opens a popup naming the POI behind the color, on one line: Best, nearest POI · HUNTINGTON 3 · 1,172.72 MW. The name is a link — following it selects that POI exactly as clicking its own marker would, so the row in the POI table, the marker on the map, and the constraints below it all follow. The MW figure is read from the POI itself and carries the POI table's own number format, so the popup and the row it selects cannot report the same bus differently.

Improved in v4.0.2

Clicking past the support radius, where the surface is drawing nothing, gives no popup at all rather than one reporting that there is nothing in reach. Clicking a POI, a cluster, a constraint, a harmer or a data layer icon puts up that feature's own popup only, with no surface popup left standing behind it.

POI markers at higher zoom​

Two related changes to the markers themselves:

  • A marker represents a site, not necessarily a single bus. POIs sharing a coordinate — the normal case for a substation, which carries a bus per voltage level — draw as one marker with a doubled ring and a count, whose popup lists every bus at that location with its voltage and headroom. Across the reference studies 60% of POIs share a coordinate with at least one other, and one substation carries 67 of them on a single point; collapsing them takes that deployment from 1,151 markers to 492.
  • Nearby sites stop being grouped into a cluster bubble above zoom 11 rather than zoom 14, so individual markers appear at a lower zoom than before. It is the zoom at which the surface has finished handing over to the markers, and like the rest of that handover it is fixed rather than configurable.

Individual markers also carry a thin dark outline, so a light-colored marker stays visible against the light basemap.

Default colors​

The default POI color ramp is a six-step cividis ramp with "no capacity" as its own darkest step, plus a seventh color above the top break. At the seven discrete steps GIPS draws, the previous default collapsed several classes into one for a deuteranope reader and again in greyscale; cividis stays ordered in both. A deployment with its own ranges is untouched — see Migrating to v4.0.