Follow on rotations: Does it exist in FC or not?

Have some feature requests, feedback, cool stuff to share, or want to know where FreeCAD is going? This is the place.
Forum rules
Be nice to others! Read the FreeCAD code of conduct!
Post Reply
DanielLeeWenger
Posts: 53
Joined: Sun Feb 02, 2020 4:02 am
Location: Santa Cruz, California
Contact:

Follow on rotations: Does it exist in FC or not?

Post by DanielLeeWenger »

OS: macOS Mojave (10.14)
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.19.20900 (Git)
Build type: Release
Branch: master
Hash: 3ad15343ebab78cd76b7e9a06a0f8d794f5075be
Python version: 3.8.2
Qt version: 5.12.5
Coin version: 4.0.0
OCC version: 7.4.0
Locale: C/Default (C)


I am a newcomer to FreeCAD and and to 3D design in general. I am not sure that what I would like to see as a FC capability already exists or not, so a posting to this Forum seems right.

The current Placement Dialog allows the specification of three rotations around the x, y and z axes of an object. After some trial and error and reading of the Forum post https://forum.freecadweb.org/viewtopic.php?f=3&t=42185 I gather that the Dialog is interpreted as, perform the z axis rotation first, then the y axis rotation and then the x axis rotation, IN THAT ORDER.

A second application of the Dialog is not applied to the existing orientation of the object, but is applied to the original orientation of the object when it was created.

My desire is to find a way of doing add on rotations to an object, continuing from the current orientation.

True, one may augment the value of a former rotation, but I do not see a way of doing an x rotation and then a y rotation and then another x rotation, for example.

If this capability now exists in FreeCAD then I would appreciate learning of it.

If this capability does not exist within FreeCAD then I would be interested in knowing if the feature is worthy of a “new feature request” in the eyes of others than myself.

If I have miss understood the situation, please let me know.

A FreeCAD aficionado.
chrisb
Veteran
Posts: 53945
Joined: Tue Mar 17, 2015 9:14 am

Re: Follow on rotations: Does it exist in FC or not?

Post by chrisb »

You can do this. In the Placement dialog you can check "Incremental" and do the rotations step by step.
A Sketcher Lecture with in-depth information is available in English, auf Deutsch, en français, en español.
DanielLeeWenger
Posts: 53
Joined: Sun Feb 02, 2020 4:02 am
Location: Santa Cruz, California
Contact:

Re: Follow on rotations: Does it exist in FC or not?

Post by DanielLeeWenger »

Thanks for the reply. I have tried that feature but have not convinced myself that this is the equivalent of what I want.

I will try again.

Ah. My most recent efforts have been applied to orienting an LCS and the Edit Datum dialog does not have that feature.

I will broaden my understanding of the Placement Dialog. If that feature does accomplish what I want than it may be that the Edit Datum dialog could stand the Incremental feature.

++++
I now understand how to use the Placement Dialog to get the result I want.

Thanks again.
Last edited by DanielLeeWenger on Tue May 05, 2020 12:22 am, edited 1 time in total.
chrisb
Veteran
Posts: 53945
Joined: Tue Mar 17, 2015 9:14 am

Re: Follow on rotations: Does it exist in FC or not?

Post by chrisb »

DanielLeeWenger wrote: Mon May 04, 2020 9:33 pm may be that the Edit Datum dialog could stand the Incremental feature.
Good idea!
A Sketcher Lecture with in-depth information is available in English, auf Deutsch, en français, en español.
mario52
Veteran
Posts: 4674
Joined: Wed May 16, 2012 2:13 pm

Re: Follow on rotations: Does it exist in FC or not?

Post by mario52 »

hi

here the last video tutorial with the last update of Placement by its programmer TheMarkster

placement task dialog tutorial w/ audio

phpBB [video]


mario
Maybe you need a special feature, go into Macros_recipes and Code_snippets, Topological_data_scripting.
My macros on Gist.github here complete macros Wiki and forum.
DanielLeeWenger
Posts: 53
Joined: Sun Feb 02, 2020 4:02 am
Location: Santa Cruz, California
Contact:

Re: Follow on rotations: Does it exist in FC or not?

Post by DanielLeeWenger »

Thank you for posting this link to the video. Just what a beginner needs, up until the demonstration of the mating of two objects. This seems quite advanced for me, a beginner. Fortunately I have been playing with Assembly 4 and I was able to tell myself, "I could do this more simply and more directly with Assembly 4". ;)

But thank you and many thanks to TheMarkster for his great job, and very soothing voice. I now want to explore his ten other videos.

I want to make the suggestion that the label "Apply incremental changes" is not as clear as it could be. One is not, in general, incrementing a previous rotation but instead is applying an additional rotation to the previous one. Also I think (I hope I am correct) that the application of a rotation with values in more than one field, ie. a rotation involving two or three axes simultaneously, is executed in a particular order. It seems this should be explicitly indicated. Please let me know if I am wrong here.
mario52
Veteran
Posts: 4674
Joined: Wed May 16, 2012 2:13 pm

Re: Follow on rotations: Does it exist in FC or not?

Post by mario52 »

hi
DanielLeeWenger wrote: Fri May 08, 2020 12:23 am I want to make the suggestion that the label "Apply incremental changes" is not as clear as it could be. One is not, in general, incrementing a previous rotation but instead is applying an additional rotation to the previous one. Also I think (I hope I am correct) that the application of a rotation with values in more than one field, ie. a rotation involving two or three axes simultaneously, is executed in a particular order. It seems this should be explicitly indicated. Please let me know if I am wrong here.
I do not know
the code returned for "incremental changes " is multiply()

Code: Select all

App.getDocument("Test_Cercles").BSpline.Placement=App.Placement(App.Vector(0,0,0), App.Rotation(0,0,3), App.Vector(0,0,0)).multiply(App.getDocument("Test_Cercles").BSpline.Placement)
mario
Maybe you need a special feature, go into Macros_recipes and Code_snippets, Topological_data_scripting.
My macros on Gist.github here complete macros Wiki and forum.
Post Reply