Line angle problem

[Jamie Myers]

Bear with me while I try to explain this. It's a little complicated. Let's say that I have a line that starts at point 10,20 and ends at point 40,30. I know, this will give a line angle of 18.43494882. Now, let's say that there is another line that runs completely opposite of this, starts at point 40,30 and ends at point 10,20 which has a line angle of 198.43494882. A 180 degree turnaround. My problem is when I try to insert a block onto one side of either of these lines using lisp. Where the insert command asks for the angle, if I put in either of these angles, it will always be on one side of the line. If my insertion point is closer to one end, then my block will be put in either on the top of the line, or below the line depending on which end the insertion point is. I'm using assoc 10 & 11 codes to find the start and end points of the line so that I can specify a certain distance from the end of the line. I dunno if this makes any sense, but it causing me problems in several of my routines not only with blocks, but with drawing lines from that line to a certain angle and/or distance away. I have a routine for creating a section line which can only be used at either 0, 90, 180, and 270 degrees. It might be a good example to use so that everyone can be on the same track. I don't know about posting it in here, because, I know that there are alot of people who make there money off of routines like this. It would be cheaper for our company to just buy these, but the seem to not understand that the time I spend on doing these routines is far more expensive. Therefore, I have to create my own if I want to stay ahead of the game. I really don't know what the proper etiquette would be for posting that.

 

[Jamie Richardson]

Is "osmode" set to 0 prior to inseringt blocks or drawing lines. Your program might be snapping to a point with the running osnaps turned on.

 

[Pierre Marcotte]

Bear with me while I try to explain this. It's a little complicated. Let's say that I have a line that starts at point 10,20 and ends at point 40,30. I know, this will give a line angle of 18.43494882. Now, let's say that there is another line that runs completely opposite of this, starts at point 40,30 and ends at point 10,20 which has a line angle of 198.43494882. A 180 degree turnaround. My problem is when I try to insert a block onto one side of either of these lines using lisp. Where the insert command asks for the angle, if I put in either of these angles, it will always be on one side of the line. If my insertion point is closer to one end, then my block will be put in either on the top of the line, or below the line depending on which end the insertion point is. I'm using assoc 10 & 11 codes to find the start and end points of the line so that I can specify a certain distance from the end of the line. I dunno if this makes any sense, but it causing me problems in several of my routines not only with blocks, but with drawing lines from that line to a certain angle and/or distance away. I have a routine for creating a section line which can only be used at either 0, 90, 180, and 270 degrees. It might be a good example to use so that everyone can be on the same track. I don't know about posting it in here, because, I know that there are alot of people who make there money off of routines like this. It would be cheaper for our company to just buy these, but the seem to not understand that the time I spend on doing these routines is far more expensive. Therefore, I have to create my own if I want to stay ahead of the game. I really don't know what the proper etiquette would be for posting that.

Would this help ?? remove unwanted parts and go whoopie all night long !!!

;;; LTR.lsp - select Line entity and Text entitiy. Rotate text based on line angle. ;;; By: Jeffery P Sanders 10/9/02 ;;; ;;; Modified March 2003 ;;; By Pierre Marcotte

(DEFUN C:LTR
(SETVAR "cmdecho" 0)
(PRINC "\n Select LINE with Correct Angle")
(IF (SETQ eset (ENTSEL " : "))
(PROGN
(REDRAW (car eset) 3)
(SETQ en (CAR eset))
(SETQ enlist (ENTGET en))
(IF (= "LINE" (CDR (ASSOC 0 enlist)))
(PROGN
(PRINC "\n Select TEXT to Match Line Angle")
(IF (SETQ eset2 (ENTSEL " : "))
(PROGN
(SETQ ept1 (CDR (ASSOC 10 enlist)))
(SETQ ept2 (CDR (ASSOC 11 enlist)))
(SETQ ang1 (ANGLE ept1 ept2))

************** This is the part you're probably after ********* (COND ((< ang1 0) (SETQ ang1 (+ ang1 (* 2 PI)))) ((AND (> ang1 (/ PI 2)) (<= ang1 PI)) (SETQ ang1 (- ang1 PI)) ) ((AND (> ang1 PI) (<= ang1 (* 1.5 PI))) (SETQ ang1 (+ ang1 PI)) ) ) ;_ end of COND
************** End of part *****************

(SETQ en2 (CAR eset2))
(SETQ enlist2 (ENTGET en2))
(SETQ enlist2 (SUBST (CONS 50 ang1)
(ASSOC 50 enlist2)
enlist2
) ;_ end of SUBST
) ;_ end of SETQ
(ENTMOD enlist2)
) ;_ end of PROGN
(PRINC "\n Select Text Entity Please. Program Aborted.") ) ;_ end of IF ) ;_ end of PROGN (PRINC "\n Enitity selected was not a LINE. Program Aborted." ) ;_ end of PRINC ) ;_ end of IF (REDRAW (car eset) 4) ) ;_ end of PROGN (PRINC "\n Nothing selected. Program Aborted.") ) ;_ end of IF (SETVAR "cmdecho" 1) (PRINC)
) ;_ end of DEFUN

Dr Fleau

 

[Jamie Myers]

Nope. The problem is having autocad read the line angle correctly. What I have gotten to work has been using alot of if functions and then its only in 4 directions. I've tried rotating the ucs, readjusting the baseangle and several other things. Rotating the UCS seems to be the most practacle, but I'm still having trouble. I would believ that it's a fairly common thing everyone does.

Let me try another example. Let's say that I had a routine to draw a window, then insert it on a wall.
If I use something like this:

(setq Line (entsel "/nPick line: "))
(setq Start (assoc 10 (entget Line)))
(setq End (assoc 11 (entget Line)))
(setq InsertionPoint (cadr Line))
(setq LineAngle Start End)
(command "_insert" MyBlock InsertionPoint "" "" LineAngle)

*If I got the syntax wrong on these I apologize. I'm trying to do this off memory. Hopefully you'll get the idea.*

If the line runs at a 45 degree angle starting at point 10,10 , then the window will be put in correctly. now, if the line was drawn at a 225 degree angle, then the window would be put in on the wrong side. How can I correct this, and make it work for *any* angle?

If you need more info, let me know.

 

[Joe Burke]

Of course: (setq LineAngle (angle Start End))

Jamie,

Maybe like this:

(setq LineAngle Start End)
(if (> LineAngle pi)
(setq LineAngle (- LineAngle pi))
)

Joe Burke

What only

 

[Jamie Myers]

Okay, that works. Let's try taking this a little farter. What happens if I want the window inserted at a specified point from the one end or the other. Let's say that I want the window center to be at 10'-0" from the start point of the line. It would insert on one end. Now if the start point was at 10,10, the window would be placed correctly. But, if the start point was to be at 100,100 then the window would insert on the wrong end. And if you think about it, what would happen if the insertion point was to be at -10,-10? Then the math used to get the 10'-0" distance gets screwed up. I know, it's starting to get complicated. Agian, if I'm not making much sense, I'll try to explain it a little better.

 

[Jamie Myers]

See my reply to Jow Burke.

 

[Jamie Myers]

Jow or Joe take your pick. ;-)

 

[Jason Wilder]

Well, a quick suggestion that comes to mind. Can you simply check the degree of the angle and then subtract 270, 180 or 90 from it?

I've done something similar to what you're talking about, in regard to angles. I've done it both ways, where I devote a portion of code to determining the 'corrected' angle required.

Such as in your window example, if the angle shows to be 225, then just subtract 180 from it before handing it to the insert command.

 

[Joe Burke]

Good points, Jason.

Jamie,

Before you go any further, maybe consider a different approach. My experience is you pretty much have to determine in advance at what point along a wall a window will be placed. So what I do is go around the plan and draw a line across the wall (extending beyond the wall on both sides) to establish the centerlines of all the windows. The program prompts the user to pick the two intersection points, inside face of wall first. Those two points establish the angle, location and wall thickness. The program draws the window on-the-fly rather than using a block. Window size is user input. It also erases the temporary centerlines.

You could do something similar using blocks. It would be a fairly simple program compared to where I think you are headed.

HTH
Joe Burke

 

[Scribble]

Jamie
would this be any help:

(setq start (assoc 10...
(setq end (assoc 11...
(if (> (dist pick start)(dist pick end))
(progn (swap start end)........

 

[Jamie Myers]

It actually goes beyond just inserting a block on a wall. I have set up my routines to use the angle of the line to determine which way to draw a line/circle/text/etc. from my line. Like Joe was talking about, not inserting a block but drawing it with lisp, I would need a *reference angle* to work from. Now Joe touched on something, putting a line through a wall to draw a window and getting the points from that. That's great for windows and doors, but what about other things. I've got a routine for section lines as stated before. I cannot get it to work for other angles. I'm sure that this would be a routine joe and you already have, so I'll send Joe and you mine and let you see what I have.

 

[Jamie Myers]

Spoke to soon Jason, I need your email address. Send it to jamie_myers at yahoo dot com.

 

[Joe Burke]

Jamie,

Just to clarify, my suggestion about drawing a line across the wall only applies to windows. For instance, I don't do that in my door insert programs. Inserting a window or a door in a wall share similar problems from a programming standpoint. What they don't have in common, in my opinion, is the thought process involved in deciding where the item should be placed.

A door is almost always placed in relation to a wall corner. Give the user a default offset from corner with an option to change it. It ain't that simple with a window where you may need to consider the window's location in relation to other windows (exterior elevation) and/or furniture layout in the room. So to me it doesn't make sense to try to interactively place a window while in the program as it does with a door. You might as well set the location of the window beforehand. Which in turn makes the programming quite a bit easier.

Joe Burke

 

[Jamie Myers]

What I planned on doing in the situation of a window or a door was to divide the exterior wall line up into 3 pieces, and depending on where on the line the insertion point is picked at, would determine if the insert will be offset from the end a predetermined distance or inserted in the middle. I have managed to get this to successfully work with exception of this line angle problem. I can get it to work a 0 and 90 degrees, but not for 180 and
270. And, what if a wall is drawn at 45 degrees? It's a problem I have had with several other routines I'm working on, not just the ones with doors and windows. I'm certain others have had problems with this. I need to learn how they got around it, or, if I'm going about the whole thing the wrong way. The methods I use to get my routines to work are valid. I've put a lot of thought into the processes and what I want to acheive. I try ot make routines which are easier for my users to work with. The less iformation they have to put into it, the better. These guys are what most people would call a nightmare. Their cad knowledge is not that great and they are lazy when it comes to their drawings. I had to creat routines for layering because they are too lazy to change the layer name before they draw. Instead of trimming or glueing lines together, they just simply draw across another line. I understand what you mean by keeping the routine as simple as possible. But if I don't put alot of extra care and attention into it, then it wouldn't be used at all. The users would complain that it's too complicated. I'd rather leave the complications and the complexity in capable hands, mine.

And don't get me wrong, you'd be amazed at how much I appreciate the help you guys are giving me. I've already learned quite a bit from this thread alone.

 

[Jason Wilder]

I sent it to your e-mail, but I'll also post it here.

This is a snipet of code I've used for a couple of my routines. The point(s) 'dir_pnt' are two arbitrary points picked by the user and then I translate a bit based on the angle. The remainder of this routine places a line that has tails on it that are drawn a certain way and then text is placed on or above the line. Which of course depending on angle needs to be drawn correctly so that it get's displayed on the drawing appropriately.

So I utilize the (trans) function for my points and turn my UCS. We operate strictly in 2D, so this is a fairly easy process to use. I've done more complicated routines in the past that utilized the trans function throughout. The most difficult part of doing it this way is keeping the process 'straight' when you're coding it. Once you're complete, it should work rather nicely. Hope this helps some.

(setq
pnt1 (getpoint "First Point of direction notation: ")
pnt2 (getpoint pnt1 "Second Point of direction notation: ") dirang (atoi (angtos (angle pnt1 pnt2))) tflag NIL )

(if (or (= dirang 0) (= dirang 90) (= dirang 180) (= dirang 270)) (progn (setq dir_pt1 pnt1 dir_pt2 pnt2 dirang_chk dirang ) ) (progn (if (and (> dirang 0) (< dirang 90)) (setq ucs_ang (itoa dirang))) (if (and (> dirang 90) (< dirang 180)) (setq ucs_ang (itoa (- dirang
180))))
(if (and (> dirang 180) (< dirang 270)) (setq ucs_ang (itoa (- dirang
180))))
(if (and (> dirang 270) (< dirang 360)) (setq ucs_ang (itoa (- dirang
360))))
(command ".ucs" "z" ucs_ang)
(setq
ucs_chk T
dir_pt1 (trans pnt1 0 1)
dir_pt2 (trans pnt2 0 1)
dirang_chk (atoi (angtos (angle dir_pt1 dir_pt2) 0 3))
)
)
)

(setq
pnt1x (car dir_pt1)
pnt1y (cadr dir_pt1)
pnt2x (car dir_pt2)
pnt2y (cadr dir_pt2)
dirlen (distance dir_pt1 dir_pt2)
fwid 0.5
)