QgsRectangle does not propose the support of orientation or Z, since its role is for the extent. A new class called QgsQuadrilateral to manage 4 vertex polygons is created. For the moment, there are only rectangles, but it will be possible to add the other shapes later.
This refactoring simplifies maptools and allows you to use the QgsQuadrilateral class in other tools.
In addition, it will allow a better management of the Z for rectangles by 3 points. Today the first Z is used, now the points will have their Z and the 4th will be projected on the plane.
This feature was developed by Loïc Bartoletti (Oslandia)