When moving an object with direct manipulation (gizmo) along a single axis sometimes the controls reverse and the object moves up when dragging down, left when dragging right, etc.
Able to reproduce this issue after turning the object upside down with the rotation provided by direct manipulation.
In addition, 2D display does not scale well depending on the current zoom factor.
Both behaviors were fixed in the two commits provided. Displacement calculation was wrong, 2D rendering did not consider zoom factor.
Could be integrated into release branch and master.