Should geometry be simplified before reprojection?

[tylanderson]

Currently the simplification tolerance is defined in EPSG:4326, and applied after the geometry is re-projected. This currently doesn't work as well near the poles (shown below)

Simplifying before re-projection would allow a good simplification tolerance that can apply across all latitudes, meaning polar geometries are simplified enough and equatorial geometries are not over simplified.

Example from #192 near the poles, where sensor detector footprints can be seen.

[ircwaves]

A single global threshold in geographic coordinates does not. Reordering the operations to stay in UTM for the simplification sounds like a good solution. The only alternative to reordering the operations would be adding a LUT mapping lat to simplification_threshold. Do you have a feel for what the failure modes look like in geom.simplify().reproject(...)? Looks like the preserve_topology defaults to True, so polygons won't vanish (become points or lines).

[tylanderson]

Do you have a feel for what the failure modes look like

I can't see simplification failing if switched to apply on the UTM coords. Additionally currently simplification is only used for product info geometry, not the product metadata, so the tolerance value being switched meters would also not cause downstream impacts