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Change Rotation Direction To Measure Clockwise instead of Counter-Clockwise

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Change Rotation Direction To Measure Clockwise instead of Counter-Clockwise

Tango
51 posts
The surveyors who have worked on our lot sent me .dxf files of the current data.  This is a big help to me, since it lets me do some simple surveying work (to figure possible house site locations) on my own.

There is one issue that creates a lot of extra work for me.  When lines are drawn on the map, they are done with compass bearing.  A line running from south (bottom) to north (top) that is rotated to the right (clockwise) by 90° (using the south end as a pivot and moving the north end of the line in the rotation), in LibreCAD, will be rotated by 270°, since LibreCAD measures the direction of rotation moving in a counter-clockwise direction.

On a compass, the direction of rotation is measured in a clockwise direction, so that same line, if it were running from west to east, would have a 90° rotation (and, if it ran from east to west, would have a 270° rotation).  But in LibreCAD, that same line would have those numbers reversed.  LibreCAD measures the degree of rotation from the top (North) and counts counter-clockwise.

If I drew a compass on paper, North is 0°, East is 90°, South is 180°, and West is 270°.  But if I have the same markings in LibreCAD and want to rotate something facing North so it faces East, then, according to LibreCAD, that's a 270° rotation.

Is there any way to tell LibreCAD to measure rotation in a clockwise direction?  My work would go MUCH faster if I didn't have to take every bearing I have from using a compass and subtract it from 360° to get the rotation I need to use in LibreCAD.
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Re: Change Rotation Direction To Measure Clockwise instead of Counter-Clockwise

LordOfBikes
Administrator
1119 posts
As every other CAD system, LibreCAD is based on a cartesian coordinate system.
Angles are measured counterclockwise and 0° is in X+ direction or east in compass notation.

There was some effort in past to implement surveying function in LibreCAD, but never in the main repository. And I don't know about the latest status.

But maybe following hints satisfy your needs:
You could nearly everywhere, where an angle is needed, enter a calculation and LibreCAD does the rest.
Try to enter 360-90 and the rotation will be 270° ccw.
This example could be more simplified, as you could enter negative angles too.
Enter -90 and you will get a rotation of 90° clockwise. So simply add a minus sign to an angle value may do the trick for you.

Armin

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Re: Change Rotation Direction To Measure Clockwise instead of Counter-Clockwise

Tango
51 posts
While that may seem like something simple, it's a HUGE help!  Thank you.  Sincerely, it does make my life easier.  I've been getting so tired of having to do the math on the calculator for each angle!
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Re: Change Rotation Direction To Measure Clockwise instead of Counter-Clockwise

LordOfBikes
Administrator
1119 posts
You're welcome! I'm glad that it works for you.

Armin
investing less than half an hour into Search function can save hours or days of waiting for a solution