alt Hacker News> the software implementation is much less trivial
Aren't most geospatial tools just doing simple geometry? And therefore need to work on some sort of projection?
If you can do the math on the spheroidal model, ok you get better results and its easier to intuit like you said, but it's much more complicated math. Can you actually do that today with tools like QGIS and GDAL?
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Many do use simple geometry. This causes endless headaches for people who are not cartographers, they don’t expect that. The good geospatial tools usually support spheroidal models but it is not the default, you have to know to explicitly make sure it uses that (many people assume that is the default).
An additional issue is that the spheroidal implementations have undergone very little optimization, perhaps because they are not the defaults. So when people figure out how to turn them on, performance is suddenly terrible. Now you have people that believe spheroidal implementations are terribly slow, when in reality they just used a pathologically slow implementation. Really good performance-engineered spheroidal implementations are much faster than people assume based on the performance of open source implementations.
This is not really a problem, unless you’re trying to simulate some 3D space orbits, physics. The crossover from geo INFORMATION systems to geo simulation systems is a bit rough, but the projections and calculations on projected cartesian space are enough for many typical questions, like distance, area, routing. However, even topology support starts getting specialized, and the use cases are more niche. I think it’s asking a bit too much from a database/storage layer to do efficient calculations outside of those supported by GEOS. At this point, you might want to import the relevant data into higher level applications.
For what it's worth, you _can't_ use spherical approaches for most data. They're only used for points, in practice. Your spatial data is inherently stored/generated in ways that don't allow spherical approaches as soon as you start working with polygons, let alone things like rasters.
Yes, spherical representations of polygon data exist, but the data you import has already been "split" and undoing that is often impossible, or at best non-trivial. And then rasters are fundamentally impossible to represent that way.
Analysis uses projections for that reason. Spherical approaches aren't fundamentally "better" for most use cases. They're only strictly better if everything you're working with is a point.
There's more to geospatial than point datasets.