Attachment Editor help

[manos]

Hello
I want to create a Datum Line at Body001. After I click the Datum Line I get the Attachment Editor.
I look at the attachment modes but they are not the same as in Part EditAttachment wiki page. (https://wiki.freecadweb.org/Part_EditAttachment)

Screenshot from 2022-07-07 01-26-52.png (301.77 KiB) Viewed 583 times

So what is going on at this page and at this Editor? Is there any other resources except the Basic Attachment Tutorial ?

[edwilliams16]

The file you uploaded just has a Body with nothing in it except its Origin object. There's no Body001. What do you want to attach the Datum line to?
@manos

[manos]

Hello
I want to create a Datum Line at Body. After I click the Datum Line I get the Attachment Editor.
I look at the attachment modes but they are not the same as in Part EditAttachment wiki page. (https://wiki.freecadweb.org/Part_EditAttachment)
So what is going on at this page and at this Editor? Is there any other resources except the Basic Attachment Tutorial ?

Screenshot from 2022-07-07 01-26-52.png (301.77 KiB) Viewed 544 times

So I changed from Body001 to Body @edwilliams16. The question is still valid .

[Bance]

The attachment dialogue is context sensitive, if there is nothing selected, then it offers the possible modes for the body objects.

In this case the body only contains the origin. It looks like FC offers some default modes in this case.

[edwilliams16]

The attachment mode editor list is context sensitive. As you start selecting points, lines, vertices etc. the list gets shorter. In the case of attaching a Datum Line, there are modes available that make no sense for a 3D object - like Through Two Points. It appears no-one has felt the desire to document this particular situation. If you have a particular mode of attachment in mind, for your Datum Line, that you can't figure out for yourself, I'm sure we can help.
@manos

[edwilliams16]

For a Datum Point, you get yet another context-sensitive attachment mode list:

Screen Shot 2022-07-06 at 2.30.51 PM.png (49.36 KiB) Viewed 502 times

Attaching a point to something requires specifying 3 degrees of freedom, a line 5 degrees and a general 3D object 6 degrees. These are inherently different.
@manos

[manos]

In this case the body only contains the origin. It looks like FC offers some default modes in this case.

As @edwilliams16 wrote

..It appears no-one has felt the desire to document this particular situation. .

It's a pity.

If you have a particular mode of attachment in mind, for your Datum Line, that you can't figure out for yourself, I'm sure we can help.

Okay thanks everybody but at the moment I think that I will abandon the wild world of 0.20 and be back for a while at the civilized land of 0.19

[manos]

Attaching a point to something requires specifying 3 degrees of freedom, a line 5 degrees and a general 3D object 6 degrees. These are inherently different.
@manos

A very useful start to think about attachments. Thanks @edwilliams16
I think that in general, this stands for placements too. Doesn't it ?

[Bance]

I will abandon the wild world of 0.20 and be back for a while at the civilized land of 0.19

Cutting off your nose to spite your face? Why do that, attachment hasn't changes since it was introduced in FC 0.17.

[edwilliams16]

Attaching a point to something requires specifying 3 degrees of freedom, a line 5 degrees and a general 3D object 6 degrees. These are inherently different.
@manos

A very useful start to think about attachments. Thanks @edwilliams16
I think that in general, this stands for placements too. Doesn't it ?

Not really. A Placement is six degrees of freedom - three for translation. (X, y, z) - three for rotation (yaw, pitch, roll). It takes six numbers to represent the rigid motion of a general object. They are encapsulated in a Placement.