Abstract: Systems, methods, devices, and other techniques for placing and rendering virtual objects in three-dimensional environments. The techniques include providing, by a device, a view of an environment of a first user. A first computing system associated with the first user receives an instruction to display, within the view of the environment of the first user, a virtual marker at a specified position of the environment of the first user, the specified position derived from a second user's interaction with a three-dimensional (3D) model of at least a portion of the environment of the first user. The device displays, within the view of the environment of the first user, the virtual marker at the specified position of the environment of the first user.

Abstract: A roll of paper (18) is stored in a container (16). Paper is drawn from the internal wrapping of the roll (18) out through an opening (20) to form a loose spiral (22) having overlaps of three thicknesses of paper. The paper is pulled by an operator. When the desired length has been pulled the paper is pulled down to cause a lever (24) to be pulled down to expose a serrated knife (26) which then cuts off the paper.