Ich habe eine Polylinie (nur Linien), die ungefähr 500 Punkte enthält. Ich möchte die Anzahl der darin enthaltenen Punkte reduzieren. Wie kann ich das in AutoCAD machen? (oder kann eine andere Anwendung sein)?
PS-Polylinien wurden aus Splines hergestellt, die in Liniensätze umgewandelt wurden. Aber der Detaillierungsgrad ist zu hoch. Ich möchte ihn verringern.
Antworten:
Dieses LISP-Skript erledigt den Job. Erstellen Sie eine LSP-Datei und fügen Sie sie zu AutoCAD hinzu. Führen Sie sie dann mit dem PLD- Befehl aus.
;;; PLDIET.lsp [command name: PLD]
;;; To put lightweight PolyLines on a DIET (remove excess vertices); usually
;;; used for contours with too many too-closely-spaced vertices.
;;; Concept from PVD routine [posted on AutoCAD Customization Discussion
;;; Group by oompa_l, July 2009] by Brian Hailey, added to by CAB, and
;;; WEED and WEED2 routines by Skyler Mills at Cadalyst CAD Tips [older
;;; routines for "heavy" Polylines that won't work on newer lightweight ones];
;;; simplified in entity data list processing, and enhanced in other ways [error
;;; handling, default values, join collinear segments beyond max. distance,
;;; limit to current space/tab, account for change in direction across 0 degrees,
;;; option to keep or eliminate arc segments] by Kent Cooper, August 2009.
;
(defun C:PLD
(/ *error* cmde disttemp cidtemp arctemp plinc plsel pldata
ucschanged front 10to42 vinc verts vert1 vert2 vert3)
;
(defun *error* (errmsg)
(if (not (wcmatch errmsg "Function cancelled,quit / exit abort"))
(princ (strcat "\nError: " errmsg))
); end if
(if ucschanged (command "_.ucs" "_prev"))
; ^ i.e. don't go back unless routine reached UCS change but didn't change back
(command "_.undo" "_end")
(setvar 'cmdecho cmde)
); end defun - *error*
;
(setq cmde (getvar 'cmdecho))
(setvar 'cmdecho 0)
(command "_.undo" "_begin")
(setq
disttemp
(getdist
(strcat
"\nMaximum distance between non-collinear vertices to straighten"
(if *distmax* (strcat " <" (rtos *distmax* 2 2) ">") ""); default only if not first use
": "
); end strcat
); end getdist & disttemp
*distmax*
(cond
(disttemp); user entered number or picked distance
(T *distmax*); otherwise, user hit Enter - keep value
); end cond & *distmax*
cidtemp
(getangle
(strcat
"\nMaximum change in direction to straighten"
(strcat ; offer prior choice if not first use; otherwise 15 degrees
" <"
(if *cidmax* (angtos *cidmax*) (angtos (/ pi 12)))
">"
); end strcat
": "
); end strcat
); end getdist & cidtemp
*cidmax*
(cond
(cidtemp); user entered number or picked angle
(*cidmax*); Enter with prior value set - use that
(T (/ pi 12)); otherwise [Enter on first use] - 15 degrees
); end cond & *cidmax*
plinc 0 ; incrementer through selection set of Polylines
); end setq
(initget "Retain Straighten")
(setq
arctemp
(getkword
(strcat
"\nRetain or Straighten arc segments [R/S] <"
(if *arcstr* (substr *arcstr* 1 1) "S"); at first use, S default; otherwise, prior choice
">: "
); end strcat
); end getkword
*arcstr*
(cond
(arctemp); if User typed something, use it
(*arcstr*); if Enter and there's a prior choice, keep that
(T "Straighten"); otherwise [Enter on first use], Straighten
); end cond & *arcstr*
); end setq
;
(prompt "\nSelect LWPolylines to put on a diet, or press Enter to select all: ")
(cond
((setq plsel (ssget '((0 . "LWPOLYLINE"))))); user-selected Polylines
((setq plsel (ssget "X" (list '(0 . "LWPOLYLINE") (cons 410 (getvar 'ctab))))))
; all Polylines [in current space/tab only]
); end cond
;
(repeat (sslength plsel)
(setq pldata (entget (ssname plsel plinc)))
(if (/= (cdr (last pldata)) (trans '(0 0 1) 1 0)); extr. direction not parallel current CS
; for correct angle & distance calculations [projected onto current construction
; plane], since 10-code entries for LWPolylines are only 2D points:
(progn
(command "_.ucs" "_new" "_object" (ssname plsel plinc)) ; set UCS to match object
(setq ucschanged T) ; marker for *error* to reset UCS if routine doesn't
); end progn
); end if
(setq
front ; list of "front end" [pre-vertices] entries, minus entity names & handle
(vl-remove-if
'(lambda (x)
(member (car x) '(-1 330 5 10 40 41 42 210))
); end lambda
pldata
); end removal & front
10to42 ; list of all code 10, 40, 41, 42 entries only
(vl-remove-if-not
'(lambda (x)
(member (car x) '(10 40 41 42))
); end lambda
pldata
); end removal & 10to42
vinc (/ (length 10to42) 4); incrementer for vertices within each Polyline
verts nil ; eliminate from previous Polyline [if any]
); end setq
(if (= *arcstr* "Straighten")
(progn
(setq bulges ; find any bulge factors
(vl-remove-if-not
'(lambda (x)
(and
(= (car x) 42)
(/= (cdr x) 0.0)
); end and
); end lambda
10to42
); end removal & bulges
); end setq
(foreach x bulges (setq 10to42 (subst '(42 . 0.0) x 10to42)))
; straighten all arc segments to line segments
); end progn
); end if
(repeat vinc
(setq
verts ; sub-group list: separate list of four entries for each vertex
(cons
(list
(nth (- (* vinc 4) 4) 10to42)
(nth (- (* vinc 4) 3) 10to42)
(nth (- (* vinc 4) 2) 10to42)
(nth (1- (* vinc 4)) 10to42)
); end list
verts
); end cons & verts
vinc (1- vinc) ; will be 0 at end
); end setq
); end repeat
(while (nth (+ vinc 2) verts); still at least 2 more vertices
(if
(or ; only possible if chose to Retain arc segments
(/= (cdr (assoc 42 (nth vinc verts))) 0.0); next segment is arc
(/= (cdr (assoc 42 (nth (1+ vinc) verts))) 0.0); following segment is arc
); end or
(setq vinc (1+ vinc)); then - don't straighten from here; move to next
(progn ; else - analyze from current vertex
(setq
vert1 (cdar (nth vinc verts)) ; point-list location of current vertex
vert2 (cdar (nth (1+ vinc) verts)); of next one
vert3 (cdar (nth (+ vinc 2) verts)); of one after that
ang1 (angle vert1 vert2)
ang2 (angle vert2 vert3)
); end setq
(if
(or
(equal ang1 ang2 0.0001); collinear, ignoring distance
(and
(<= (distance vert1 vert3) *distmax*)
; straightens if direct distance from current vertex to two vertices later is
; less than or equal to maximum; if preferred to compare distance along
; Polyline through intermediate vertex, replace above line with this:
; (<= (+ (distance vert1 vert2) (distance vert2 vert3)) *distmax*)
(<=
(if (> (abs (- ang1 ang2)) pi); if difference > 180 degrees
(+ (min ang1 ang2) (- (* pi 2) (max ang1 ang2)))
; then - compensate for change in direction crossing 0 degrees
(abs (- ang1 ang2)); else - size of difference
); end if
*cidmax*
); end <=
); end and
); end or
(setq verts (vl-remove (nth (1+ vinc) verts) verts))
; then - remove next vertext, stay at current vertex for next comparison
(setq vinc (1+ vinc)); else - leave next vertex, move to it as new base
); end if - distance & change in direction analysis
); end progn - line segments
); end if - arc segment check
); end while - working through vertices
(setq
front (subst (cons 90 (length verts)) (assoc 90 front) front)
; update quantity of vertices for front end
10to42 nil ; clear original set
); end setq
(foreach x verts (setq 10to42 (append 10to42 x)))
; un-group four-list vertex sub-lists back to one list of all 10, 40, 41, 42 entries
(setq pldata (append front 10to42 (list (last pldata))))
; put front end, vertex entries and extrusion direction back together
(entmake pldata)
(entdel (ssname plsel plinc)); remove original
(setq plinc (1+ plinc)); go on to next Polyline
(if ucschanged
(progn
(command "_.ucs" "_prev")
(setq ucschanged nil) ; eliminate UCS reset in *error* since routine did it already
); end progn
); end if - UCS reset
); end repeat - stepping through set of Polylines
(command "_.undo" "_end")
(setvar 'cmdecho cmde)
(princ)
); end defun - PLD
(prompt "\nType PLD to put PolyLines on a Diet.")
Ich habe einen Utility Call Reduce geschrieben, der das macht. Es ist eine kompilierte Autolisp fas-Datei, die wie eine normale lsp-Datei ausgeführt wird. Sie können es hier herunterladen: https://www.theswamp.org/index.php?topic=27724.0 .
Die lisp-Routine ist vielleicht das beste Angebot für Sie, aber ich verwende den Overkill-Befehl, um Punkte von Polylinien zu entfernen (wenn der Befehl aktiv ist, gehen Sie zu den Einstellungen). Es handelt sich um ein Express-Tool, das normalerweise zum Entfernen doppelter Linien verwendet wird, jedoch zur Optimierung von Polylinien dient. Das einzige, worauf Sie achten müssen, ist, wenn Ihre Polylinie eine Breite hat. Übermaß tötet normalerweise Breiten.
Prost.
Wenn Sie Nashorn haben, funktioniert "SimplifyCrv" ziemlich gut. Ich bin mir nicht sicher, wie es funktioniert, aber ich hatte ein ähnliches Problem. Mit diesem Befehl konnte die Anzahl der Kontrollpunkte in einer Polylinie über die mit autoCAD geladenen Befehle hinaus verringert werden.
Bitte siehe Bild hier:
Dies ist ein sehr gutes Dienstprogramm für PLine, um die Dateigröße zu reduzieren. Wurden oben jedoch 2 grüne Punkte gelöscht, wird die PLine scharf (nicht tangential). Bitte überlegen Sie.