Decoration -> Scale Bar uses a misleading planimetric measurement

[qgib]

Author Name: Max Muh (Max Muh)
Original Redmine Issue: 20587
Affected QGIS version: 3.5(master)
Redmine category:decorations

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The map scale is shown wrongly - 20m instead of 12,4m.

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• qgis fehler.png (Max Muh)

[qgib]

Author Name: Jürgen Fischer (@jef-n)

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• subject was changed from Maßstab wird falsch angezeigt to map scale not shown correctly

[qgib]

Author Name: Jürgen Fischer (@jef-n)

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• description was changed from Hallo, der Maßstab im Hauptfenster wird falsch dargestellte, zeigt 20 m an, sind in Wirklichkeit aber 12,4 m. MfG. to The map scale is shown wrongly - 20m instead of 12,4m.

[qgib]

Author Name: Jürgen Fischer (@jef-n)

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• description was changed from The map scale is shown wrongly - 20m instead of 12,4m. to The map scale is shown wrongly - 20m instead of 12,4m.

!qgis_fehler.png!

[qgib]

Author Name: Jürgen Fischer (@jef-n)

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• description was changed from The map scale is shown wrongly - 20m instead of 12,4m.

!qgis_fehler.png! to The map scale is shown wrongly - 20m instead of 12,4m.

!qgis%20fehler.png!

[qgib]

Author Name: Borys Jurgiel (@borysiasty)

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Currently, the scale bar always show planimetric distance. Especially when working in EPSG:4326 and the scale bar is displayed in metres (see also #22187), users may assume the measurement is ellipsoidal, what is not true.

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• subject was changed from map scale not shown correctly to Decoration -> Scale Bar uses a misleading planimetric measurement

[qgib]

Author Name: Borys Jurgiel (@borysiasty)

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• version was changed from 3.4.0 to 3.5(master)
• priority_id was changed from Low to Normal

[Stapawe]

@borysiasty @jef-n It is so very misleading it should be at least switched off for nonellipsoidal projections. In projects in Transverse Mercartors or Lambert Azimuthal Equal Area CRS' it works correctly.