[Feature Request] Part Design - Vertically/Horizontally equidistant constraint

[GeneFC]

Hmm...I'm not sure what is being asked for IS symmetry. By definition symmetry is the same on either side of the "line of symmetry". So, for a line (L1) to be symmetric around another line (L2). The only time the condition can be met is when L1 is perpendicular to L2.

That's the elementary school version of symmetry. There are lots of other types.

I gave up and do not plan to reenter the argument.

Gene

[drmacro]

Hmm...I'm not sure what is being asked for IS symmetry. By definition symmetry is the same on either side of the "line of symmetry". So, for a line (L1) to be symmetric around another line (L2). The only time the condition can be met is when L1 is perpendicular to L2.

That's the elementary school version of symmetry. There are lots of other types.

I gave up and do not plan to reenter the argument.

Gene

Yes, elementary, and as far as I can find, classic definition.

Please provide a reference for symmetry that does not define it as a the mirror image across a line of symmetry.

I ask because I am interested in what words mean, or obscure uses, it is sort of a life long hobby.

I'm not arguing for, or against, implementation of such a tool. I know how to accomplish it with what is currently availble and find nothing honorous about doing it. I simply have no horse in that race.

[chrisb]

Please provide a reference for symmetry that does not define it as a the mirror image across a line of symmetry.

In FreeCAD we can make only points be symmetric to something else (I know that we can select a line and make it symmetric to a point, but that also just makes the endpoints symmetric to the point). To be precise: we can make two points be symmetric to something else.
To answer your question: in that case there is always the middle line between the points which can be used to create a line symmetry. But I would not define it that way.

In general we have the notion of point symmetry, where a geometric object is mirrored at a point, which means in 2D that a rotation of 180° maps it to itself. The function f(x) = x^3 is an example for this with the origin being the symmetry point. As there is already a general definition of such symmetry I would use this as the definition in FreeCAD too.

[drmacro]

...
In general we have the notion of point symmetry, where a geometric object is mirrored at a point, which means in 2D that a rotation of 180° maps it to itself. The function f(x) = x^3 is an example for this with the origin being the symmetry point. As there is already a general definition of such symmetry I would use this as the definition in FreeCAD too.

I think I said this in my earlier response...where I said symmetry around a point is currently the way the requested functionality can be done with existing tools. No?

[chrisb]

I think I said this in my earlier response.

Indeed. I hadn't reread the whole topic, and it is what you asked for: a non line symmetry , but I may have understood things wrong.

[user1234]

Please provide a reference for symmetry that does not define it as a the mirror image across a line of symmetry.

From my daily work: rotationsymmetry, pointsymmetry. The mirrorsymmetry is a special case in the symmetry.

Also i do not see the need of an extra constraint for that. Yet you need only one click more (symmetrical reference) to do the job. Else you need extra constraints and therefore extra place (symbols, lists, ..... ) for that.

Greetings
user1234

[leoheck]

Moved the topic.
(You have created quite some feature request among all your posts and should know that they go to the Open discussion forum.)

Yeah, a long time ago, I was doing such things on the Open Discussion forum, and then that time, you used to blame me because of that. Then I totally changed my way by posting things on this user help forum. Then, now - maybe because you know me, or because you are seeing value in my requests - you are moving these things to an Open discussion forum, which is great. But I feel I will be always wrong haha.

Anyways, thanks for helping me.

[leoheck]

Please provide a reference for symmetry that does not define it as a the mirror image across a line of symmetry.

Also i do not see the need of an extra constraint for that. Yet you need only one click more (symmetrical reference) to do the job. Else you need extra

Alright. Sometimes we don't have an extra constraint for that. But sure, we can also create one more.

> Yet you need only one click more (symmetrical reference) to do the job.

This is not true if the default and current Symetri is the default option. You will have to click one more if you chose to use one of the choices I am proposing, maybe.

[leoheck]

but I may have understood things wrong.

Yeah, I feel you understand 90% of my posts this way. Sorry, maybe I am not that good at explaining these things since my background is not related to this kind of world. I am a computer engineer, so I am trying my best to explain things here.

[chrisb]

Yeah, I feel you understand 90% of my posts this way.

So for a start I understand already 10%. Let's improve it.