topic Re: Create a Rectangle or a Polygon with AREA CONSTRAIN in Dynamic Blocks Forum

Create a Rectangle or a Polygon with AREA CONSTRAIN

Anonymous — Wed, 27 Oct 2021 21:54:48 GMT

Hello People,

I am Saram a Student of B.Arch and still learning AutoCAD. I wanted to Draw a few Parametric Shapes (Rectangle or a Polygon) with an Area Constrain. Like a Rectangle or a Polygon with An Area of 20000sqft (Where if I change the Length the width is automatically adjusted) but I am unable to do it can you kindly help me understand how to do it? any reference material would be a great help.

Someone on the forum have done this and also posted the file but I am unable to understand how it was done

Link: Constrained area block wont move other parameters

If anyone can look into the file (in above link) and help me create one for myself would be great help. I just want the same thing but want to do it for multiple blocks. like a block for 20000 sqft one for 25000sqft one for 34000sqft etc.

Currently Im just using the FIELD Command to manually approximate the Area of an Object but that's not very efficient. If I could create a block just like yours and change the area and move to adjust the height or width of rectangle it would be great.

Looking forward for a reply.

Re: Create a Rectangle or a Polygon with AREA CONSTRAIN

fkp7057 — Thu, 28 Oct 2021 04:53:20 GMT

hello Created one rectangular block for 25sqmm area for example.

used gematric and dimension constraint. here I made x length as available Y length will vary as per X length.

eg. 25sqmm area

X length : 8mm

Y Length: area/X length (25/8) = 3.125 (this will derive from formula)

Re: Create a Rectangle or a Polygon with AREA CONSTRAIN

j.palmeL29YX — Thu, 28 Oct 2021 09:11:25 GMT

@Anonymous wrote:

I wanted to Draw a few Parametric Shapes (... Polygon) with an Area Constrain. Like ... a Polygon with An Area of 20000sqft (Where if I change the Length the width is automatically adjusted)

A polygon doesn't have a length and a width. So it is impossible to solve what you are asking for (only the rectangle, but this is not a regular polygon). If we talk about regular polygons, the length of all (equal) edges depends directly on its number of edges and its area.

If this is what you're looking for, see attached example. the visibility grip let you choose the number of edges, in the property window you can type any area value. Of course you can add other more polygons.

Feel free to ask if you need further help.

[EDIT]: Small error in 8-sided polygon fixed, 7-sided polygon added

Re: Create a Rectangle or a Polygon with AREA CONSTRAIN

j.palmeL29YX — Thu, 07 Dec 2023 13:21:29 GMT

Here an improved and error fixed version. Ignore the "Test Polygons.dwg" above.

Re: Create a Rectangle or a Polygon with AREA CONSTRAIN

adminH8DL5 — Thu, 07 Dec 2023 07:35:02 GMT

This is a bit old but I'll give it a go, since this is exactly what I need, whithout attributes lablels:

Since I don't know how to recreate personnalized properties blocks I don't manage to add attributes to this block.

Could you let me know how to do that?

I need it with 3 attributes.

Thank you!

Re: Create a Rectangle or a Polygon with AREA CONSTRAIN

j.palmeL29YX — Thu, 07 Dec 2023 08:11:36 GMT

What do you need the three attributes for? What should their content be? I don't yet understand your request. (I'm afraid "attributes" is the wrong term in this context?)
Do you mean perhaps, you want to add three other number of edges? (If yes, which number?)