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opengisch / qgis-swiss-locator

Swiss Geoadmin layer and feature search for QGIS 3
https://www.opengis.ch/2024/06/25/swiss-locator-plugin-3-0-is-here-with-exciting-features/
GNU General Public License v3.0
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Swiss profiles return ellipsoidal distances, QGIS profiles use cartesian ones #86

Closed gacarrillor closed 4 months ago

gacarrillor commented 4 months ago

For reference, see QGIS issue and another related plugin issue.

This is the result of a Swiss profile when using a QGIS project in EPSG:3837 (I'm measuring the profile line on the main QGIS canvas in both ellipsoidal and cartesian modes):

swiss_profile_on_3857

Approximately the same profile when using a QGIS project in EPSG:2056 (which is the EPSG requested by the Profile API):

Measurements for EPSG:2056, in both ellipsoidal and cartesian modes are almost the same, the difference is a matter of millimeters.

image

gacarrillor commented 4 months ago

A possible solution to avoid tweaking QGIS code would be to calculate our own (cartesian) distances and only use heights from the profile API (ignoring the distances it returns). This depends on the QGIS-CH requirements.