topic Re: Dynamic double circle in Dynamic Blocks Forum

Dynamic double circle

Anonymous — Mon, 21 Jan 2019 09:35:06 GMT

Hello,

I'm trying to create double circle where i can stretch to bigger or smaller outer circle, but same time my inner circle should maintain same distance from out circle. In other words radius of inner should be (outer radius)-constant. What happens with linear scale action that distance between circles get bigger when i scale.

In picture desired bigger circle is at bottom and not desired at top. I have tried with arcs, with increment list, adding block table and trying to add variables in there, constrains but nothing seem to be working well with circles.

Re: Dynamic double circle

h_s_walker — Mon, 21 Jan 2019 10:17:00 GMT

Welcome to the Forums

Here you go. The block involves two scale actions and a linear stretch.

Re: Dynamic double circle

Anonymous — Mon, 21 Jan 2019 10:30:25 GMT

Hello,

Amazing, thank you so much. This is exactly what I was trying to do 🙂

Re: Dynamic double circle

j.palmeL29YX — Mon, 21 Jan 2019 11:55:49 GMT

... or using constraints: see attached.

cadder

Re: Dynamic double circle

lvson — Thu, 09 Oct 2025 07:49:25 GMT

Hello,

I know the topic is a few years old but i am going to give it a go anyway.

I am looking for a simmilar block to the above set problem, but i would like the difference in circles to be adjustable trought a parameter. In other words, being able to set the distance between the two circles.

The case is that, in my line of work, we normaly have the information about the inner diameter and the "thickness". We already have a block with an inner and outer diameter which does what it needs to, but i would like to change the outer diameter option to the "thinkness" option (to avoid a bit of manual calculating).

Wondering if that is possible!

Re: Dynamic double circle

h_s_walker — Thu, 09 Oct 2025 08:13:59 GMT

@lvson Try the attached block

Re: Dynamic double circle

j.palmeL29YX — Thu, 09 Oct 2025 08:21:23 GMT

One of several ways:

Re: Dynamic double circle

lvson — Thu, 09 Oct 2025 10:30:13 GMT

Thanks for the response both!

They both work fine, the first one seems a bit easier understanable what it "does" to me, as i can see the parameters.

I also tried to apply the same system just now to a squared / rectangle form. On the circle i could use the "fix" constrain to the center. On the square i cant fix the center so the scale actually moves it from the geometric center of the square. Would you guys have a solution for that?

I would prefer to keep using scale with a full width linear parameter (for the inner square width). So that in both the circle and square option you put in the "diameter". I can make the square one work if i use a linear parameter for only half the square width. But in that case the user would need to remember that the Circle and Square option use different inputs. (Diameter and Radius)

Thanks in advance!

Re: Dynamic double circle

h_s_walker — Thu, 09 Oct 2025 11:34:01 GMT

@lvson I'm not entirely sure what you want to happen, but check the attached. The block has two visibility states, one for the circle and one for the square

Re: Dynamic double circle

lvson — Thu, 09 Oct 2025 12:33:40 GMT

Hey Howard,

Thanks for responding again, i can understand it aint clear. My english description is not the best 😉

Basicly i want exacly the same as the Circle block you made, but then with a Square. With the condition, that the linear parameter for the inner square, should still be full inner square width.

I have this block made already, but then with halve the linear parameter. This is how we use it now:

The new Circle one uses a linear parameter for the full inner width, and that is the preferable situation. If i do this with the square tho, it doesnt scale from the centerpoint.

Is this description more clear for you?

Re: Dynamic double circle

Brock_Olly — Thu, 09 Oct 2025 13:38:11 GMT

Just copy exactly what Howard did with his circle block. Make sure for the scale action you set it to 'independent' and move the scale basepoint (blue grip when selecting the scale action) to the center of the block.
Default is dependent and uses the start point of the linear parameter.