Vanishing point or three mutually orthogonal directions can be found. Vanishing point A vanishing point is a point on the image plane of a perspective drawing where the two-dimensional perspective projections (or drawings) of mutually parallel lines in three-dimensional space appear to converge. When the set of parallel lines is perpendicular to a picture plane, the construction is known as one-point perspective, and their vanishing point corresponds to the oculus, or "eye point", from which the image should be viewed for correct perspective geometry. Traditional linear drawings use objects with one to three sets of parallels, defining one to three vanishing points.
Point-to-point construction from electrical hazards. A few large brand names still use terminal strip-type point-to-point boards, but usually for special product lines. Electric guitar amplifier manufacturer Marshall have reissued some of their older models, using this type of construction as a design feature, although their standard products have long used PCBs. Thermionic valve equipment usually does not have the valves mounted on the PCB in order to avoid heat damage, but instead use PCBs for the wiring, achieving the economy of mass-produced PCBs without the heat damage. Prototypes which are subject to modification are often not made on PCBs, using instead breadboard