Multiple wall selection

[kwvanderlinde]

Identify the Bug or Feature request

Resolves #5324

Description of the Change

Adds support to WallTopologyTool for selecting multiple walls at one time. There are two ways to modify the selection:

1. Left clicking. Without holding shift, this is the same behaviour as before (selecting one wall). Holding shift will toggle whether the clicked wall is selected.
2. Left-dragging. This draws a selection box similar to other tools. When the mouse is released, walls within the selection box will become the new selection. If shift is held, the walls will instead be added to the existing selection instead of replacing the selection.

When multiple walls are selected, the configuration panel will blank out any options that don't have a common value for all walls. When changing any option, including a blanked out option, the new value will be applied to all selected walls.

Possible Drawbacks

Should be none

Documentation Notes

The wall topology tool supports these new actions:

• Shift+left click will add or remove the clicked wall from the current selection.
• Dragging with the left mouse button will draw a selection box. Releasing the left mouse button will set the walls inside the selection box as the selected walls. If the shift key is held, the newly selected walls will be added to the existing selection instead of replacing the selection.

Release Notes

• Add ability to select multiple walls using shift+left clicking or left-dragging.

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