In one aspect, a method of 3-D printing includes: providing a volume of a photosensitive composition having an axis of rotation and an angular motion relative to at least one light projector; optically projecting light onto a flat surface of the volume, wherein the flat surface is orthogonal to the axis of rotation; and printing an object from the volume of photosensitive composition based on the optical projections. In other aspects, a printing assembly for volumetric additive manufacturing (VAM) printing, another method of 3-D printing, and another printing assembly for VAM printing are also disclosed.