Polygone along a line

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Angelos
Posts: 107
Joined: Mon Jan 17, 2022 6:21 pm

Polygone along a line

Post by Angelos »

Do you think wpuld be possible drawing a polygon along a line?
Eric Pousse
Posts: 1064
Joined: Sat Dec 03, 2011 12:31 pm
Location: Tours - France

Re: Polygone along a line

Post by Eric Pousse »

Sorry Angelos, I don't understand what you mean.

Cordialement.
Eric Pousse
Angelos
Posts: 107
Joined: Mon Jan 17, 2022 6:21 pm

Re: Polygone along a line

Post by Angelos »

Sorry.
I have a line, with a specific measure and angle. I want to drawing a polygone with one of its sides coincident with the line.
So click on the first point of the line, than on the final one and i’ve got my polygone.
Eric Pousse
Posts: 1064
Joined: Sat Dec 03, 2011 12:31 pm
Location: Tours - France

Re: Polygone along a line

Post by Eric Pousse »

Ha do you mean a regular polygon?!
Eric Pousse
Angelos
Posts: 107
Joined: Mon Jan 17, 2022 6:21 pm

Re: Polygone along a line

Post by Angelos »

Yes
Eric Pousse
Posts: 1064
Joined: Sat Dec 03, 2011 12:31 pm
Location: Tours - France

Re: Polygone along a line

Post by Eric Pousse »

Bonjour Angelos,

There is not a tool to do that (nor in RealCADD).
But it is easy to calculate and draw this polygon.
With :
N : number of sides of the polygon you want
Lc : length of the base line (and of the sides of the polygon)

Begin to draw a perpendicular line from the base line in direction of the center of the polygon you want
Move this line to the center of the line
You have now simply to set the length of this perpendicular line to have the center of the polygon
This length is :
L = Lc / 2 / tan(360 / N / 2)

Voilà !
You can now draw the polygon from the point of the perpendicular which is the center of the polygon to one end of the base line.

Cordialement.
Eric Pousse
Angelos
Posts: 107
Joined: Mon Jan 17, 2022 6:21 pm

Re: Polygone along a line

Post by Angelos »

Thank you very much
Angelos
Posts: 107
Joined: Mon Jan 17, 2022 6:21 pm

Re: Polygone along a lin

Post by Angelos »

But … i don’t obtain the result.

50 / 2 / tan (360 / 8 / 2) = 44,81

The regular polygon of 8 sides from the center to one side of base line has 39,27 as side
Angelos
Posts: 107
Joined: Mon Jan 17, 2022 6:21 pm

Re: Polygone along a line

Post by Angelos »

Now it works perfectly with formula:

Lc : (2 * tan(180°: N))

Thank you
Eric Pousse
Posts: 1064
Joined: Sat Dec 03, 2011 12:31 pm
Location: Tours - France

Re: Polygone along a line

Post by Eric Pousse »

It is the same formula.
Eric Pousse
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