Hi all,
I’m working on a flight path analysis system that uses terrain data for clearance calculations, and I have a few questions about how geometric error is defined and exposed in quantized mesh terrain tilesets.
Pipeline understanding
My current understanding of how a tileset like Cesium World Terrain is built is roughly: source DEMs are mosaicked and reprojected into a tiled raster, which is then triangulated into a TIN per tile,similar in spirit to the approach used by tin-terrain. In that model, the geometric error for a given tile would represent the maximum vertical deviation between the TIN mesh and the source raster.
Is that an accurate high-level description of the pipeline? Or is the geometric error defined differently, for example, as a function of the source data resolution rather than the actual triangulation error?
Concrete example — Cesium World Terrain in Canada
The Cesium World Terrain data sources page lists an approximate resolution of 30 m for Canada. My question is: does the geometricError in the tileset JSON reflect the actual mesh-vs-raster deviation for those tiles, or is it derived from the nominal source resolution (e.g., 30 m projected to screen-space error)?
Per-tile geometric error
Finally, is per-tile geometric error available anywhere, either in the tile metadata or via a separate endpoint? I’m interested in choosing zoom level based on geometric error.
Thanks in advance, happy to provide more context about the use case if helpful.