# lines wrt to angle of elevation of other lines

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Hi Everybody,

I have a tremendous problem in drawing inclined lines wrt to other lines. One example is straight line AB drawn 135 deg to the horizontal and 1000 units long. I want to draw another straight line AC, that is from point endpoint A, again 1000 units long. I want to draw it in such a way that the line is 90 deg from line AB.

I know I can do it simply by 135 deg - 90 deg equalling 45 deg and drawing the line 1000 unit 45 deg from the horizontal. However I want to know how do we draw line set at relative angle from other object angle of inclination, without doing the maths???

Next thing is where can I get a free block of a man or woman (in causual clothes) standing to put it before a front elevation?

Thank you in advance, a prompt and detailed answer will be much welcomed.

Nicolas.

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You need to get hold of a lisp routine called MCR.LSP. That way you can copy rotate an object to suit what you want. I'll post it here. if you have problems with it, just yell, many members here will fill you in with how it works:

MCR.LSP

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Hi,

Thank you very much for the swift answer. However I am far from grasping how this will work and help me. Its just beyonf my ability. You see I understand that ACAD angle works counterclockwide and I can draw any line of any dimension in 1:1 at any angle for example a line at 45 degree 100 unit long, I type 100

I will check tonight if I can work out the routine, how to install and use it and I will let you know tomorrow if I was able to do something good about it.

Thank you very much for the good work.

Nicolas.

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Hey, Nic. Tutor time.

Acad can measure angles both clockwise and counterclockwise. Just depends on how you set it up in the first place. The default is called Architectural standards, which starts from East at 0 degrees, and measures counterclockwise. For civil/survey we change that to north being 0 degrees, and measuring clockwise.

But that does not matter for you at the moment.

Just draw another line over the one you want to rotate. Then type the command ROTATE and pick that line, doesn't matter which one gets picked. When you are asked for a base point, pick the base point you want the rotation to occur about.

Then when asked to enter the rotation angle, just type 45. If it rotates to the wrong side, just start again. This time enter -45. If you are happy with that, go back and delete the first rotation line. It really is that simple.

If you are still unsure, please get back to us. If it worked, and you understand now, still get back to us. We love to know that our assistance has been a help.

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In this particular case, where you want a 90° angle, one way would be to offset the line AB by 1000. Then C is in the correct position, then grab the other end of the line, and dock it onto A.

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Draw line AB, for line AC at the command line prompt, LINE Specify first point: Select the PERPINDICULAR OSNAP, then select the line you want to be PERPINDICULAR to, then select Point A, then type in 1000.

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HI Everybody,

I do believe that the information will indeed help me. I will read all of the post and do all the required homeworks and practicing and I will be back to you upon success.

Nicolas.

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LINE

Specify first point:

Specify next point or [undo]: @50

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If one returns to the title of the thread of how to draw lines wrt other lines, then perhaps a simple solution would be to draw a line, then copy that line onto itself, and then rotate the copied line to the required angle from the first line

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Hi Everybody,

I have tried the first explanation by Cullen and it works. I used the copy command to recopy the line AB (1000 unit, 135 from horizontal) unto itself. Then I used the ROTATE command on one of the line (original or copy, I don't know), select A as base point and and rotate by -90 degree and it was 90 deg from line AB which is what I wanted. line AC which is 1000 unit and 90 deg from AB.

The second explanation from Eldon does work. I offset AB (still 1000 units, 135 from horizontal) and docked the farthest northern endpoint onto A. However, I don't understand the logic behind this method? How about other ANGLES from A?

SLW210's explanation seemed good and I was able to reproduce it at home. I used LINE command, Shift-Right Click Perpendicular osnap, click the line AB, and hover the picbox on A, type 1000 and there is a line 1000, 90 deg or perp from AB. However, I wish to know if there is a similar system for the other angles and also I did not see any DEFERRED OSNAP. How to get it?

As for Bigal? Unable to do it, surely due to some setting problem. What is the principle behind: @50

Thank you in advance, a prompt and detailed answer will be much welcomed.

Nicolas.

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Hi Everybody,

The second explanation from Eldon does work. I offset AB (still 1000 units, 135 from horizontal) and docked the farthest northern endpoint onto A. However, I don't understand the logic behind this method? How about other ANGLES from A?

Nicolas.

This was a particular solution for the 90° angle only, because Offset gives a truely parallel line. Solutions were given for general angles in the other replies

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Nic, one of the things you will soon learn, is that there are many ways to "skin the cat" in acad (quote Tiger).

What I like about you is that you try all suggestions out. THAT IS GOOD.

Keep approaching acad that way, and you will soon become pretty damn good at it all.

But most important, do what you are doing, if you don't understand something, keep asking questions.

We members have a tendancy to under explain everything. We all suffer from writers cramp. :lol:

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A method to do other than perpindicular (90 deg.) is to use POLAR TRACKING and have "Relative to last segment" checked in the Polar Tracking settings.

Depending on the situation, I have used every method mentioned.

I believe Deferred Osnaps are only with Perpendicular and Tangent. You will see Deferred, when you select one of these Osnaps, when prompted to select the first point. These 2 Osnaps are a reference, so if you select them before your reference has been established AutoCAD knows the point can only be located once the other point is selected.

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Hi,

I know that it's an old post but I have found a solution that I have been using ever since. I enter UCS and enter OB for object and click the object. The UCS turn to meet the orientation of the line. I set Orthogonal on by pressing F8 if it's not and then I can draw any perpedicular line as I wish. I have also create two macro 1. for UCS W (world) to automatically return to normal 2. for UCS OB (object) to draw orthogonal or other set angle from incline lines and this method is working just fine for me. Whatever, even after so much time, I wish to thank all for their suggestions and I remain to study and fully comprehend some of them.