line-y-at-x

Arguments: point1 point2 x

Returns the y coordinate where a line has a particular x coordinate, or nil for a vertical line.

The first two arguments are position objects that specify any two distinct points on the line. The last argument is a real number for the x coordinate. The returned value is a real number or nil.

As usual, position objects should contain integers. See make-position. See also line-x-at-y and line-y-at-x-x-y.

Copyright (c) 1998-2012, Franz Inc. Oakland, CA., USA. All rights reserved.
Documentation for Allegro CL version 8.2. This page is new in the 8.2 release.
Created 2010.1.21.