line-x-at-y

Arguments: point1 point2 y

Returns the x coordinate where a line has a particular y coordinate, or nil for a horizontal 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 y 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-x-y and line-y-at-x.

Copyright (c) 1998-2016, Franz Inc. Oakland, CA., USA. All rights reserved.
This page is new in the 8.2 release.
Created 2016.6.21.