Add a way of region-selecting other than parallel to screen coordinates

[dg1727]

Currently, the bandbox / "rubberband selection rectangle" has its edges parallel to screen coordinates.

Units are often arranged according to the map coordinate axes, though. E.g., when ungarrisoned from a building or when constructing a building. Selecting some units that are in this kind of array, without selecting nearby units, can be cumbersome if the camera is pointing in such a direction that map coordinates are oblique to screen coordinates.

Suggested solution:

A UI for rotating the bandbox while it is being drawn. For example, while the mouse is down, one key rotates the bandbox axes clockwise and another key rotates them the other way. The endpoint of the bandbox can simultaneously be moved with the mouse, as in the existing method, although the start point of the bandbox would stay fixed.

This would be a fairly general solution, in that, when map coordinates are parallel to screen coordinates, a group of units arranged obliquely to map coordinates could also be easily selected, unlike at present.

[leper]

Why not just rotate the camera (Q,E) and use shift to extend the current selection?

[historic_bruno]

You can also use Ctrl+Arrows to tilt the camera while selecting. I think that is enough to help with selections.