Because that's what QGIS elevation profile tool supports.
By doing so, we ensure users won't get displaced profile graphs (too much difference between ellipsoidal and cartesian distances) nor displaced exported features (using 3d cartesian distances, exported features won't match in the graph and will be displaced with respect to 2d distances calculated by the elevation profile tool).
Fix #86
Fix #87
For the record, this is the deviation when using 3d cartesian distances:
Points are exported features (distance/elevation table) from the profile, which have their Z coordinate. The elevation profile tool doesn't take these Z coordinates into account when calculating distances, so features appear displaced with respect to its correspondent 3d cartesian distance given by the Swiss locator calculation. As a result, we use 2d cartesian distances avoiding these displacements.
Because that's what QGIS elevation profile tool supports.
By doing so, we ensure users won't get displaced profile graphs (too much difference between ellipsoidal and cartesian distances) nor displaced exported features (using 3d cartesian distances, exported features won't match in the graph and will be displaced with respect to 2d distances calculated by the elevation profile tool).
Fix #86 Fix #87
For the record, this is the deviation when using 3d cartesian distances: Points are exported features (distance/elevation table) from the profile, which have their Z coordinate. The elevation profile tool doesn't take these Z coordinates into account when calculating distances, so features appear displaced with respect to its correspondent 3d cartesian distance given by the Swiss locator calculation. As a result, we use 2d cartesian distances avoiding these displacements.