topic Re: What is the purpose of reverse command because I don't see any changes while using this command?? in AutoCAD Forum

What is the purpose of reverse command because I don't see any changes while using this command??

Anonymous — Mon, 12 Apr 2021 14:16:35 GMT

Can you show me importance and purpose of reverse command?

Re: What is the purpose of reverse command because I don't see any changes while using this command??

Patchy — Mon, 12 Apr 2021 14:28:07 GMT

It help when you use in labeling a bearing for that line.

NE or SW in Civil drafting.

Re: What is the purpose of reverse command because I don't see any changes while using this command??

pendean — Mon, 12 Apr 2021 14:36:15 GMT

How are you using it exactly? That's most likely the problem if there is one.

Re: What is the purpose of reverse command because I don't see any changes while using this command??

Anonymous — Mon, 12 Apr 2021 14:37:50 GMT

If you have polylines made up of custom linetypes, such as having text embedded, with more than 2 vertices, reverse command will reverse the "reading order of the text" on the segment(s) you select. I use text as an example, but it would do the same thing with symbols, geometry, etc used in the linetype.

I use it for making things like piping lines, with the size and type of pipe embedded in the linetype, such as 3"CHWS Makes the text easier to read when it all runs the same way, which it sometimes doesn't when I break, join, add vertices, etc.

Re: What is the purpose of reverse command because I don't see any changes while using this command??

elzohry2007 — Mon, 12 Apr 2021 14:54:28 GMT

Reverses the vertices of selected lines, polylines, splines, and helixes, which is useful for linetypes with included text, or wide polylines with differing beginning and ending widths.

Vertices of selected objects are reversed.

For example, when a linetype with text is specified with relative rotation in a LIN file, the text in the linetype might be displayed upside down. Reversing the vertices of the object changes the orientation of the text.

The REVERSE command does not change the orientation of text where rotation is specified as upright.

Re: What is the purpose of reverse command because I don't see any changes while using this command??

Kent1Cooper — Mon, 12 Apr 2021 15:10:18 GMT

In addition to other things already mentioned, another thing affected by the direction something is drawn is the placement of Points or Blocks in the MEASURE command. The specified spacing is measured from the "starting" end of the path object, and any leftover distance beyond a multiple of that spacing will be past the last Point or Block placed, at the "ending" end of the path. If you REVERSE the path object, the placements under MEASURE will then be measured from the other end from where they were before the REVERSE, and the results will [most of the time] be different.

Re: What is the purpose of reverse command because I don't see any changes while using this command??

Kent1Cooper — Mon, 12 Apr 2021 15:35:43 GMT

@elzohry2007 wrote:

....

The REVERSE command does not change the orientation of text where rotation is specified as upright.

That is the crucial thing to know in regard to Linetypes with either Text or Shapes embedded in them -- the difference between the R and U flags in the embedding code in the linetype definition. See Help about it [here for embedded Text, but the same for embedded Shapes]. If a Linetype is defined with the U flag for Text, you wouldn't see the change with REVERSE, because the Text parts would all go to the more upright orientation. But if the Linetype has, for example, an asymmetrical arrangement of dashes and gaps between Text parts, since those dashes and gaps are unaffected by the Text orientation but are affected by the drawn direction, REVERSE would change the upper one here to the lower one, or vice versa:

Re: What is the purpose of reverse command because I don't see any changes while using this command??

Anonymous — Mon, 12 Apr 2021 16:30:27 GMT

(also to @elzohry2007 )

I learned something new, thanks folks.

To create my "custom text" linetypes, I took linetype defintions that existed previously (before I hired in back in '08), and simply modified the text string(s) and spacing parameters to fit the needs of the moment, adding to that .lin file over the years. I never knew about the "A", "R" and "U" flags (and apparently neither did the prior CAD guys). Adding the "U" will save me some future "go back and fix this" issues when I miss a "backwards" or "upside down" line. I like problems I can prevent better than ones that must be fixed!

Re: What is the purpose of reverse command because I don't see any changes while using this command??

3wood — Mon, 12 Apr 2021 22:48:18 GMT

I think MEASURE command starts from the end which is closer to the pick up point, not depends on the direction of the linear object.

Re: What is the purpose of reverse command because I don't see any changes while using this command??

Anonymous — Tue, 13 Apr 2021 04:59:39 GMT

What do you mean by reverses the vertices of selected lines?

Suppose a polyline of M shape

If we apply reverse command, M→ reverse to W. Are you saying this?

Re: What is the purpose of reverse command because I don't see any changes while using this command??

Anonymous — Tue, 13 Apr 2021 06:45:02 GMT

I think MEASURE command starts from the end which is closer to the pick up point, not depends on the direction of the linear object.

→ Right

Re: What is the purpose of reverse command because I don't see any changes while using this command??

ВeekeeCZ — Tue, 13 Apr 2021 08:05:33 GMT

In civil engineering, we use special linetypes to indicate the flow (sewerage in this example)

Re: What is the purpose of reverse command because I don't see any changes while using this command??

Anonymous — Tue, 13 Apr 2021 09:09:11 GMT

So you mean basically reverse command is used to show flow direction of vertices. Right ?

Re: What is the purpose of reverse command because I don't see any changes while using this command??

Anonymous — Tue, 13 Apr 2021 09:18:45 GMT

can you please give me simple straight forward definition of reverse command. I will ask you later if I feel problem on your definition.

Re: What is the purpose of reverse command because I don't see any changes while using this command??

3wood — Tue, 13 Apr 2021 10:00:15 GMT

It is also very useful when you draw a battered wall with a customized linetype. You can easily changed the battered wall direction with command REVERSE.

Re: What is the purpose of reverse command because I don't see any changes while using this command??

Kent1Cooper — Tue, 13 Apr 2021 11:42:16 GMT

@3wood wrote:

I think MEASURE command starts from the end which is closer to the pick up point, not depends on the direction of the linear object.

You are correct [I wonder whether it worked as I thought long ago and has been changed, but I nearly never use it], except in the case of a CIRCLE, in which it measures CCW from the 0°-direction-from-the-center, no matter where you pick on it. But REVERSE won't work on a Circle anyway -- if you need something like a flow-direction or battered-wall linetype on a Circle, and need the linetype to go the other way, you would need to convert it to a Donut-type Polyline, such as with ReverseDirection.lsp >here<. Then the result in MEASURE would be affected by where you pick on it.

In experimenting about that, I discovered something unexpected that you might want to know about if you're using REVERSE on a closed Polyline, and if where it starts and ends matters: it doesn't simply change the direction from the starting vertex, but changes the starting vertex location!

Re: What is the purpose of reverse command because I don't see any changes while using this command??

Kent1Cooper — Tue, 13 Apr 2021 11:46:32 GMT

@Anonymous wrote:

can you please give me simple straight forward definition of reverse command. I will ask you later if I feel problem on your definition.

>Help about it< is, I think, as simple and straight-forward as anything I could offer.

Re: What is the purpose of reverse command because I don't see any changes while using this command??

3wood — Tue, 13 Apr 2021 12:25:04 GMT

At least in one case you can not reverse a polyline.

As shown below, a polyline with 2 vertex but closed.

Re: What is the purpose of reverse command because I don't see any changes while using this command??

Anonymous — Tue, 13 Apr 2021 12:46:48 GMT

OK then according to me

If this line 1-------2-----------------3 have direction →

Using reverse command,

3------2---------------1 now have direction ←.

Reverse command doesn't affect the drawing look, it only makes the end point of drawing as a starting point and vice versa.

Is it correct ?

Re: What is the purpose of reverse command because I don't see any changes while using this command??

Kent1Cooper — Tue, 13 Apr 2021 13:09:38 GMT

@3wood wrote:

At least in one case you can not reverse a polyline. .... a polyline with 2 vertex but closed.

It works for me:

The original was drawn with DONUT and equal inside and outside radii -- a zero-width two-half-circle-arc-segments closed Polyline. I even tried moving a vertex so it wasn't two equal arc segments, as in your image, but it still REVERSEd correctly.