divvy?

I have two questions about the divvy.vision demo:
1- How can you replicate the effect of darkening/blackening the earth so that its almost black like they did?

2- Where do the wire buildings come from? Are they all just individual 3D models? or is there a source where you get get all the building data?

Sai,

The cartoDB Dark Matter map was used for the divvy basemap: http://cartodb.com/basemaps/

For an entirely black basemap, I have used loaded a black pixel as a single tile image provider like below:
new Cesium.SingleTileImageryProvider({url: ‘blackPixel.png’})

In this demo, the wire buildings are from Chicago’s open data portal (https://data.cityofchicago.org/Buildings/Building-Footprints/qv97-3bvb), downloaded as a shapefile, and a selection converted to geojson using QGIS (http://www.qgis.org/). Once the flat footprints are loaded into Cesium, they are extruded using the “stories” property within each footprint.

In the future, it would be great to load buildings dynamically using OSM Buildings - similar to this post here:

https://groups.google.com/forum/#!topic/cesium-dev/LISfsDpF0-8/discussion