Draw lines (by angle) with respect to the previous one

José Carlos Ferreira

Hello

Is it possible to draw a free line, with let's say, random parameters, and then, draw another line at the end of the previous one, but using relative angles or other relative parameters???

As an example:

I draw a line with, let's say with length of 5, and angle of x (x is an unknown parameter) and then I want to keep drawing another line from the end of the previous one but with 90º with respect to x... How can this be accomplished?

Richard Webb

 I don't see a quick way to do this as a continuous motion that is analogous to entering a relative Cartesian movement. Drawing a line and then entering, say, @2,2 for the next point doesn't have a similar syntax which enters a relative distance and a relative angle, like @2&lt;@90 or something.<div>

But this can be done in two steps. First draw the line at the random parameters and then align the coordinate system to that line with the UCS command. Then when entering a distance/angle from a line drawn at the end of the first line, the angles will be relative to that line.

Roy Klein Gebbinck

Make sure that POLAR is on, and that the 'Relative' option of POLARMODE is checked.

José Carlos Ferreira

@Richard Webb:

 I don't see a quick way to do this as a continuous motion that is analogous to entering a relative Cartesian movement. Drawing a line and then entering, say, @2,2 for the next point doesn't have a similar syntax which enters a relative distance and a relative angle, like @2&lt;@90 or something. <div>

But this can be done in two steps. First draw the line at the random parameters and then align the coordinate system to that line with the UCS command. Then when entering a distance/angle from a line drawn at the end of the first line, the angles will be relative to that line.

In fact I remember to have used something like that (@2&lt;@90) in the past, but I don't remember if it was with respect to Cartesian coordinates or with respect to angles!</p>

I'll try that syntax later tonight...

José Carlos Ferreira

@Roy Klein Gebbinck:

Make sure that POLAR is on, and that the 'Relative' option of POLARMODE is checked.

I can also try that and check if it does what I need!

Thanks for the replies!

José Carlos Ferreira

I'm sorry for this post, but it should be in Linux area! I created it here by mistake!

José Carlos Ferreira

@Roy Klein Gebbinck:

Make sure that POLAR is on, and that the 'Relative' option of POLARMODE is checked.

That worked... Great!

José Carlos Ferreira

@Richard Webb:

 I don't see a quick way to do this as a continuous motion that is analogous to entering a relative Cartesian movement. Drawing a line and then entering, say, @2,2 for the next point doesn't have a similar syntax which enters a relative distance and a relative angle, like @2&lt;@90 or something. <div>

But this can be done in two steps. First draw the line at the random parameters and then align the coordinate system to that line with the UCS command. Then when entering a distance/angle from a line drawn at the end of the first line, the angles will be relative to that line.

@Richard Webb, I could not insert that syntax into BricsCAD command line! I mean, I type "line", then I try to enter that syntax (@2&lt;@90), it says "Invalid command".</div>

Richard Webb

@José Carlos Ferreira:

@Richard Webb, I could not insert that syntax into BricsCAD command line! I mean, I type "line ", then I try to enter that syntax (@2&lt;@90), it says "Invalid command". </enter>

Yes, that's correct. I worded that poorly but it was intended to convey that while there is a Cartesian relative command, there is not a corresponding command for polar coordinates (distance and angle).

If that capability would be useful in your work flow then submit a support request to have something like that added. I'm not sure if it would break anything or how difficult it would be to add but filing a support request is the first step to get it in front of the developers. If it is ever added then you can say it was your initiative that got it included. Geek cred!   ;-)

Roy Klein Gebbinck

Keep in mind that you can use relative cylindrical coordinates but you will have to calculate the angle yourself.
[code]: LINE
Start of line: 0,0
Angle/Length/Undo/<End point>: @100&lt;10
Angle/Length/Follow/Undo/<End point>: @50&lt;100
Angle/Length/Follow/Close/Undo/<End point>: @100&lt;190
Angle/Length/Follow/Close/Undo/<End point>: close[/code]

José Carlos Ferreira

@Richard Webb:

Yes, that's correct. I worded that poorly but it was intended to convey that while there is a Cartesian relative command, there is not a corresponding command for polar coordinates (distance and angle).

If that capability would be useful in your work flow then submit a support request to have something like that added. I'm not sure if it would break anything or how difficult it would be to add but filing a support request is the first step to get it in front of the developers. If it is ever added then you can say it was your initiative that got it included. Geek cred!   ;-)

Ok... I understood it the wrong way! Anyway, the relative coordinates are only possible when using Cartesian coordinates, right? They cannot be used with Cartesian coordinates AND angles at the same time, is that it?

Scott McKenzie

Another way is to use the rotate command utilizing the copy option.

José Carlos Ferreira

@Scott McKenzie:

Another way is to use the rotate command utilizing the copy option.

Can you explain that better?

Best regards

Psy

PS: This thread should be moved to Linux as I have created it in Windows section by mistake!

Joe Dunfee

 I don't think it matters if it in the windows or linux areas, since they probably behave the same.

If I needed to do what you need to do, I would draw the 1st line, and then for the 2nd line just copy the first one from the start to its end.  Then, I would rotate that copy the degrees I need.  Of course, its distance would be wrong.

If you were needing to do this a lot, a LISP (or what ever language you are comfortable with) would be useful.  These languages were created precisely for this sort of situation.

Such a program might follow the following sequence.

Start the custom routine, which prompts for the 1st point, then the 2nd point.  

Then the routine rotates the ucs by the angle of the 1st line.  Then, it prompts you to enter the 3rd point, which will have its 0 angle equal to the 1st line.  Perhaps it continues this until you hit esc.

-joe