Always snap to grid
From Unreal Wiki, The Unreal Engine Documentation Site
Shapes the red builder brush into a box.
- Height, Width, Breadth
- The dimensions of the brush.
- The thickness of the box's walls, if the brush is hollow. Note that this number is the total wall thickness along each axis, not the thickness of each individual wall. For example, if you want each wall of your box to be 16 UUs thick, you would set WallThickness = 32. Thus WallThickness must be less than the smallest of Height, Width, and Breadth. This setting has no effect if Hollow is false.
- Not sure. Despite its name, this setting has no effect on the default group to which new brushes are assigned.
- If true, creates a hollow box rather than a solid one. See WallThickness above.
- If true, tessellates each side of the box. In other words, each face of the box will be composed of two triangles rather than a single rectangular polygon. Use this only if you plan on vertex-editing the box in such a way that it will end up with more than six faces.