Vanishing point as the "direction point", as lines having the same directional vector, say "D", will have the same vanishing point. Mathematically, let be a point lying on the image plane, where is the focal length (of the camera associated with the image), and let be the unit vector associated with , where . If we consider a straight line in space with the unit vector and its vanishing point , the unit vector associated with is equal to , assuming both are assumed to point towards the image plane. When the image plane is parallel to two world-coordinate axes, lines parallel
Parallel Lines make "Parallel Lines" an extremely popular album in the United Kingdom, where it was a number-one hit and charted for 106 weeks during the late 1970s. "Q" magazine called the album "a crossover smash with sparkling guitar sounds, terrific hooks and middle-eights more memorable than some groups' choruses." In a retrospective appraisal of 1970s post-punk albums, "Spin" magazine's Sasha Frere-Jones said "Parallel Lines" may have been "the perfect pop-rock record" and Blondie's best album. Christian John Wikane from "PopMatters" later called it "a creative and commercial masterpiece by Blondie ... indisputably one of the great, classic albums of the rock