Perspective (graphical) on the horizon line. All lines parallel with the viewer's line of sight recede to the horizon towards this vanishing point. This is the standard "receding railroad tracks" phenomenon. A two-point drawing would have lines parallel to two different angles. Any number of vanishing points are possible in a drawing, one for each set of parallel lines that are at an angle relative to the plane of the drawing. Perspectives consisting of many parallel lines are observed most often when drawing architecture (architecture frequently uses lines parallel to the x, y, and z axes). Because it is rare to have
Distance from a point to a plane the point on a plane formula_33 closest to an arbitrary point formula_34 is formula_2 given by where and the distance from the point to the plane is Distance from a point to a plane In Euclidean space, the point on a plane formula_1 that is closest to the origin has the Cartesian coordinates formula_2, where The distance between the origin and point formula_2 is formula_5. If what is desired is the distance from a point not at the origin to the nearest point on a plane, this can be found by a change of variables that moves the origin to