Author: ksprotte Date: Tue Jan 29 04:17:50 2008 New Revision: 2412

Modified: branches/bos/projects/bos/m2/geometry.lisp branches/bos/projects/bos/m2/packages.lisp Log: added DISTANCE and POINT-IN-CIRCLE-P to geometry.lisp

Modified: branches/bos/projects/bos/m2/geometry.lisp ============================================================================== --- branches/bos/projects/bos/m2/geometry.lisp (original) +++ branches/bos/projects/bos/m2/geometry.lisp Tue Jan 29 04:17:50 2008 @@ -1,8 +1,25 @@ - (in-package :geometry)

;; a point in this package is represented ;; as a list (x y) +(defmacro with-point (point &body body) + (let* ((*package* (symbol-package point)) + (x (intern (format nil "~A-X" (symbol-name point)))) + (y (intern (format nil "~A-Y" (symbol-name point))))) + `(destructuring-bind (,x ,y) ,point + ,@body))) + +(defmacro with-points ((&rest points) &body body) + (if (null points) + `(progn ,@body) + `(with-point ,(car points) + (with-points (,@(cdr points)) + ,@body)))) + +(defun distance (point-a point-b) + (with-points (point-a point-b) + (sqrt (+ (expt (- point-a-x point-b-x) 2) + (expt (- point-a-y point-b-y) 2)))))

;; maybe change this function to take a ;; point as an argument? @@ -22,6 +39,9 @@ pjy piy)) result))

+(defun point-in-circle-p (point center radius) + (<= (distance point center) radius)) + ;;; directions

;; A direction can be represented either

Modified: branches/bos/projects/bos/m2/packages.lisp ============================================================================== --- branches/bos/projects/bos/m2/packages.lisp (original) +++ branches/bos/projects/bos/m2/packages.lisp Tue Jan 29 04:17:50 2008 @@ -2,7 +2,9 @@

(defpackage :geometry (:use :cl :iterate :arnesi) - (:export #:point-in-polygon-p + (:export #:distance + #:point-in-polygon-p + #:point-in-circle-p #:find-boundary-point #:region-to-polygon))