popupid: carve](Worldcraft) A subtractive geometric building tool integrated into the Worldcraft/Valve Hammer Editor editor. It is accessible through: the right click menu the menu item Tools, Carve the keyboard shortcut Shift+Ctrl+C the toolbar button Taken directly from the Worldcraft help file: In the editor, any solid can be used to carve a volume out of other solids. For example, you can place a solid within the room's wall and tell Hammer to subtract the solid from the wall -- effectively punching a hole right through the wall! This feature is not limited to using cubic shapes as a carving tool: any solid -- cylinders, cubes and wedges -- can be used to carve other solids. See Also: Carving Responsibly.
(to carve) See Brush subtraction.
a tool in WC that lets you cut into another brush. Often, very often, leads to compiling problems or extra wpolys/bad r_speeds/lag. New mappers should avoid until they fully understand how the problems are created. Most mappers "build" a hole in a brush one side at at time, brush by brush.