Curves workbench

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GlouGlou
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Re: Curves workbench

Postby GlouGlou » Tue Jul 27, 2021 8:42 pm

How to twist or constraint the whole surface following curve for a direction. (Z here).
Maybe twisting all isocurves? :roll: the make a new surface?
... (Chris, if you can write a new macro to do that, be certain i support you. :D)
Attachments
TwistSurface.FCStd
(8.39 KiB) Downloaded 14 times
Capture.JPG
Capture.JPG (30.06 KiB) Viewed 804 times
keithsloan52
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Re: Curves workbench

Postby keithsloan52 » Wed Jul 28, 2021 12:26 am

Attached is a picture of an imported 3dm file also attached.
74CEA9AC-5E50-4298-8F7A-62B39852E88E.jpeg
74CEA9AC-5E50-4298-8F7A-62B39852E88E.jpeg (62.18 KiB) Viewed 756 times
Rhino.FCStd
(48.8 KiB) Downloaded 16 times
It is a series of FreeCAD/OCC <BSplineSurface object>'s

It would be good if the curves workbench had a facility to select and edit the surfaces i.e. Alter control points, add control points etc

Info shows information about the structure of the surfaces, what I would like to see is the ability to edit the surface.
CF28C5AB-341F-4F8A-9FCF-CEA22CBA5408_4_5005_c.jpeg
CF28C5AB-341F-4F8A-9FCF-CEA22CBA5408_4_5005_c.jpeg (28.16 KiB) Viewed 680 times
Last edited by keithsloan52 on Wed Jul 28, 2021 8:29 am, edited 1 time in total.
keithsloan52
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Re: Curves workbench

Postby keithsloan52 » Wed Jul 28, 2021 1:00 am

In a similar line to previous post here is a BezierCurve imported from a 3dm file.
C622EFF5-2FAC-45D6-90CE-8A79AF0E55CC_4_5005_c.jpeg
C622EFF5-2FAC-45D6-90CE-8A79AF0E55CC_4_5005_c.jpeg (17.76 KiB) Viewed 746 times
BezierCurve.FCStd
(7.89 KiB) Downloaded 15 times
Is it possible to select the control points and adjust the curve, if not could such a facility be added - Thanks
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Chris_G
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Re: Curves workbench

Postby Chris_G » Wed Jul 28, 2021 3:19 pm

GlouGlou wrote: Tue Jul 27, 2021 8:42 pm How to twist or constraint the whole surface following curve for a direction. (Z here).
Maybe twisting all isocurves? :roll: the make a new surface?
... (Chris, if you can write a new macro to do that, be certain i support you. :D)
Unfortunately, I don't get what result you're expecting.
Is it something like this ?
Attachments
TwistSurface_2.FCStd
(55.27 KiB) Downloaded 14 times
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GlouGlou
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Re: Curves workbench

Postby GlouGlou » Wed Jul 28, 2021 7:13 pm

Thanks but all the curvature on X is lost. It's not I'm looking for.
It's funny I've got a same surface with mixed curves. :D
Attachments
TwistSurface_3.FCStd
(379.13 KiB) Downloaded 11 times
Last edited by GlouGlou on Wed Jul 28, 2021 8:05 pm, edited 1 time in total.
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GlouGlou
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Re: Curves workbench

Postby GlouGlou » Wed Jul 28, 2021 7:42 pm

keithsloan52 wrote: Wed Jul 28, 2021 1:00 am Is it possible to select the control points and adjust the curve, if not could such a facility be added - Thanks
Maybe by converting the curve into a freehand_bspline.??? I don't know if Chris could be.
keithsloan52
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Re: Curves workbench

Postby keithsloan52 » Wed Jul 28, 2021 7:55 pm

GlouGlou wrote: Wed Jul 28, 2021 7:42 pm
keithsloan52 wrote: Wed Jul 28, 2021 1:00 am Is it possible to select the control points and adjust the curve, if not could such a facility be added - Thanks
Maybe by converting the curve into a freehand_bspline.??? I don't know if Chris could be.
I got the impression from an early post that maybe this was possible in the early days, but if I select the 'PolyCurve'
(Probably the import should have given a better name) but in the Report View I get

Code: Select all

20:51:58  *** Interpolation curve control keys :

    a - Select all / Deselect
    i - Insert point in selected segments
    t - Set / unset tangent (view direction)
    p - Align selected objects
    s - Snap points on shape / Unsnap
    l - Set/unset a linear interpolation
    x,y,z - Axis constraints during grab
    q - Apply changes and quit editing
20:51:58  execute is disabled during editing
Freehand_BSpline has a yellow background and the PolyCurve has at one end
CC79C586-31DB-42DA-BFE8-9B82F1F45759_4_5005_c.jpeg
CC79C586-31DB-42DA-BFE8-9B82F1F45759_4_5005_c.jpeg (3.53 KiB) Viewed 587 times
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GlouGlou
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Re: Curves workbench

Postby GlouGlou » Wed Jul 28, 2021 8:09 pm

maybe all poles could be move into the new freeahand when creating.
keithsloan52
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Re: Curves workbench

Postby keithsloan52 » Wed Jul 28, 2021 8:42 pm

GlouGlou wrote: Wed Jul 28, 2021 8:09 pm maybe all poles could be move into the new freeahand when creating.
To me that seems a bit Kludge.

The curve comes from a file called BezierCurve.3dm which is a sample file supplied with Rhino.
It clearly is a Bezier Spline although the rhino3dm importer calls it a PolyCurve (but the rhino3dm importer is a bit like that.
For example when one imports a Cone it actually creates a surface for the curved section and one or two flat areas for the ends.)

If I use the Curves Workbench 'Display Info ...' Icon then it shows the control points. I think the underlying OCC Shape is a Bezier Spline.
So Curves Workbench knows what it is and should be able to use it without copying

The problem with copying rather than just handling is one then has to delete the former.

Consider for example a user wishes to import a 2D design with Bezier's from Rhino, make some minor changes and then use the shape
with the Path workbench, it is messy to have to copy and delete the original.

Also consider that it is not only FreeCAD that is built on top of Open Cascade, if one wants to transfer info/designs between such software then such software can use the OCC facility to save as a BREP. Transfer such a file which contains a OCC Bezier Spline and you have to then convert it to your workbenches equivalent. If one implements facilities without taking the underling software into consideration then your build islands.
I personally found it frustrating that there were a number workbench tackling curves and curved surfaces that ended up as islands where as if they had built on the curves and curved surfaces of the underlying layers things would have been so much better.
drmacro
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Re: Curves workbench

Postby drmacro » Mon Aug 02, 2021 12:27 pm

Not sure if this is my problem, or FC, or Curves...

If you select an edge from a Body that has been transformed (as well as the sketch for the body having an attachment offset) and discretize the edge, it is at the original angle of the sketch offset, but at the original origin of the sketch.
Snip macro screenshot-88b1b4.png
Snip macro screenshot-88b1b4.png (89.87 KiB) Viewed 351 times
Attachments
DiscretizeAttachmentOffset.FCStd
(34.14 KiB) Downloaded 11 times
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