| Allegro CL version 8.2 Unrevised from 8.1 to 8.2. 8.1 version |
Arguments: position position-vector-or-list
Returns whether position is inside the polygon that is defined by position-vector-or-list. position should be a position instance (as created with make-position), and position-vector-or-list should be either a vector or a list of positions that define a polygon, just as you would pass to draw-polygon or fill-polygon.
The beginning position should not be repeated at the end of the vector or list to "close" the polygon, and so a vector or list of three positions would specify a triangle. A position that is exactly on a line segment is considered to be "inside" the polygon.
This function is used internally by polygonal hotspot
s (see hotspot-region), but can be used by itself if
desired.
Copyright (c) 1998-2016, Franz Inc. Oakland, CA., USA. All rights reserved.
This page was not revised from the 8.1 page.
Created 2010.1.21.
| Allegro CL version 8.2 Unrevised from 8.1 to 8.2. 8.1 version |