PartDesign new development, MultiBody and more

About the development of the Part Design module/workbench. PLEASE DO NOT POST HELP REQUESTS HERE!
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wsteffe
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Re: PartDesign new development, MultiBody and more

Post by wsteffe »

I have just observed that in my last picture the panels appear differently than in all other examples in this thread.
The autohiding works but the panel are not blurred together, they still confined in separate sub-windows.
I don’t understand why my FC appears different.
wsteffe
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Re: PartDesign new development, MultiBody and more

Post by wsteffe »

the selection problem was due to an accidental switching to the openinventor navigation mode.

I should have thought about it before, I am sorry for having reported that.
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-alex-
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Re: PartDesign new development, MultiBody and more

Post by -alex- »

realthunder wrote: Thu Feb 18, 2021 1:03 pm Hi, can you please provide a file that shows problem with drafting pad, presumably with sheetmetal?
1- The issue can be about sheetmetal workflow for example because Taper_angle breaks Shapebinder (or produces Bspline faces instead of planes):
(here I unfold just to show that unfolding is almost ok previously enabling taper angle option, don't mind about that)
FC-Link_taper-angle_breaks_shapebinder.gif
FC-Link_taper-angle_breaks_shapebinder.gif (380.87 KiB) Viewed 4475 times
Taper-angle_breaks_shapebinder.FCStd
(38.01 KiB) Downloaded 135 times

2- or about Xref as well. Here the issue is due to the fact the taper angle changes lines to Bsplines. So that the Xref is broken:
FC-Link_taper-angle_leads_line_to_BSpline.gif
FC-Link_taper-angle_leads_line_to_BSpline.gif (435.11 KiB) Viewed 4475 times
Taper-angle_leads_line_to_BSpline.FCStd
(28.57 KiB) Downloaded 117 times
realthunder
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Re: PartDesign new development, MultiBody and more

Post by realthunder »

wsteffe wrote: Fri Feb 19, 2021 4:27 am I have just observed that in my last picture the panels appear differently than in all other examples in this thread.
The autohiding works but the panel are not blurred together, they still confined in separate sub-windows.
I don’t understand why my FC appears different.
You can go to the Preference, and select a different overlay style sheet, either Dark-Outline or Light-Outline.
Try Assembly3 with my custom build of FreeCAD at here.
And if you'd like to show your support, you can donate through patreon, liberapay, or paypal
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OficineRobotica
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Re: PartDesign new development, MultiBody and more

Post by OficineRobotica »

wsteffe wrote: Fri Feb 19, 2021 4:27 am I have just observed that in my last picture the panels appear differently than in all other examples in this thread.
The autohiding works but the panel are not blurred together, they still confined in separate sub-windows.
I don’t understand why my FC appears different.
Realthunder has given us the possibility to click on the panel headers and drag them around . Just click and drag on the area where the "Combo view" label is located . It also snaps to screen edges.

panelArangement.jpeg
panelArangement.jpeg (333.12 KiB) Viewed 4435 times

A more appropriate thread for this would be : https://forum.freecadweb.org/viewtopic.php?f=34&t=45349
wsteffe
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Re: PartDesign new development, MultiBody and more

Post by wsteffe »

Hello, RT and OfficineRobotica, thanks for your suggestions.

In the past days I tried FC again, last time was more than a year ago. I think it has improved a lot but there are still a few things I do not like.

The most important perhaps is that the in FC Bodies are essentially equivalent to Parts. A Body has a coordinate system, a separate history and (probably because of this choice) it is not possible to use in a sketch, as a reference, an object which belongs to a different body.

Usually (with other CAD systems) when I need such kind of separation I use a set of parts, not a set of bodies.
If I am putting more bodies in a single part it is because I need to use geometrical entities of other bodies inside of a sketch which defines a given body.

To me the body concept should be used to define a geometrical entity.
In CATIA the "Body" term is reserved to a solid. CATIA has another kind of data structure, named Geometrical Set,
which may be used to define more generic objects such as, in example, a set of faces (which is translated into a TopoDS_Compound in OCC).

Part and Assembly are different concepts related to a higher level organization of the CAD document.
When I export a CATIA Part into a step file, the Part itself is translated into a PRODUCT while a Body is translated
into a MANIFOLD_SOLID_BREP. The same happens also with ZW3D. But with FC Body and Part are both translated into a PRODUCT.
And this seems to confirm my impression that in FC Body a Part are equivalent concepts.
wsteffe
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Re: PartDesign new development, MultiBody and more

Post by wsteffe »

Hello,
I have just understood that the problem I was speaking in my last post can be fixed with a simple renaming of FC objects:
1) current Body should be renamed as Part
2) current Part should be renamed as Assembly.

Now that it is possible to create more solids in a Body (old name), which should be a Part (in the correct naming), that Part is
in effect a multi-body Part.

To see that the naming I am suggesting is the correct one you have just to export a FC document into a step file and than import that file inside of CATIA or ZW3D. If the FC document contains a few Bodies in a Part you will see that inside of ZW3D the bodies will be recognized as parts and the FC Part will be recognized as an assembly.
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Re: PartDesign new development, MultiBody and more

Post by realthunder »

wsteffe wrote: Tue Feb 23, 2021 6:02 am Hello,
I have just understood that the problem I was speaking in my last post can be fixed with a simple renaming of FC objects:
1) current Body should be renamed as Part
2) current Part should be renamed as Assembly.
Yes, you are right. And this concept difference has been discussed before. There is another factor at play, that is how OCC maps its shape type to STEP entities as shown here. OCC does not have concept of Part/Body. It's just normal shape vs. compound, and some options for the developer to choose whether to treat the compound as assembly or not. Right now, FC Body can only export the tip solid. You can export other solids using Link. I'll add options to make it easy to export other solids in the future.
Try Assembly3 with my custom build of FreeCAD at here.
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-alex-
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Re: PartDesign new development, MultiBody and more

Post by -alex- »

realthunder wrote: Thu Feb 18, 2021 1:03 pm I have just added this feature. It is accessible through 'Pick geometry' menu. Alt + right click any element in the 'Pick geometry' menu will bring up another menu for element history. Alt + Shift + right click will bring a menu showing derived geometries of that element. These two action can be considered as trace back and forward into the model history. These two actions are available as two dedicated command 'Part_GeometryHistory' and 'Part_GeometryDerived'. But they don't have shortcut assigned by default.
Hi, late reply sorry, lack of time...


Several comment about this:
1- thank you for your work!
2- when hovering objects in tree view I can't see features highlighting anymore: did you remove or change something about highlights?
FC-Link-no_highlight_when_hovering_treeview_features.gif
FC-Link-no_highlight_when_hovering_treeview_features.gif (100.68 KiB) Viewed 4123 times
3-
Alt + right click any element in the 'Pick geometry' menu will bring up another menu for element history. Alt + Shift + right click will bring a menu showing derived geometries of that element.
I have synced your branch after this announcement but I'm not sure to see your point. Do you mean this:
Pick_menu_Alt-RMB-no-visible-effect.gif
Pick_menu_Alt-RMB-no-visible-effect.gif (193.09 KiB) Viewed 4123 times
I can't get any special menu with Alt+RMB compare with RMB only. Am I wrong?
4- BTW I'm not sure the above Part_GeometryHistory' and 'Part_GeometryDerived' corespond to my expectation when I said
I mean about enabling feature in tree-view by selecting some face of the 3D model in main view area
I was expecting a way to activate a PartDesign object in tree view by selecting a face element in 3D view. The element would be related to the activated treeview object, would be a child of object in some way.
For example in the gif below, all faces but the cylindrical one are generated by Pad feature. So, while selecting the cylindrical face I would like edit the Pocket feature. Then when selecting any flat face I would like edit Pad feature:
cyl_face_edit_pocket_-flat_face_doesnt_edit_Pad.gif
cyl_face_edit_pocket_-flat_face_doesnt_edit_Pad.gif (301.42 KiB) Viewed 4123 times

Thanks for your attention.
wsteffe
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Re: PartDesign new development, MultiBody and more

Post by wsteffe »

realthunder wrote: Tue Feb 23, 2021 9:27 pm OCC does not have concept of Part/Body.
In fact the Body term doesn't have a standard meaning but the "Part" term has.

In Catia a Body is a container for a single solid. Its purpose is just to make it possible its activation which means that the result of any subsequent operation (in example of an extrude) is added to the solid of that body. The Geometrical Set has the same purpose but for all other kind of objects (not solid).

The body concept is not used in ZW3D because its extrude operation allows to choose if the result has to be a new shape or it has to be added to (or subtracted from) an existing solid.

It seems to me that the FC extrude is intended to work as in ZW3D (not as in Catia) and I am very happy with this choice. So I think that in FC as in ZW3D there is no need to use the Body concept by just Assembly, Part and Shapes (Solids and Surfaces). The Group container could still be useful to put more shapes in a compound.

But the Part and Assembly concepts are universally recognized by all CAD systems. These concepts are present also in OCC but are not formalized as a TopoDS_Shape. They are higher level concepts and are formalized inside of the OCAF data structure. These concepts are also used (with different naming) in the STEP format which is a well recognized standard. The mapping between OCC and STEP entities reported in your link is restricted to the TopoDS_Shape(s) and doesn't tell the whole story.

Anyway the fact that the FC STEP Exporter translates a Body into a step PRODUCT (the Body name is assigned to the PRODUCT name) is a good choice and is coherent with the fact that what now is called a Body is in effect a Part.

A Solid defined in a Part (currently named a Body) should be translated into MANIFOLD_SOLID_BREP('SOLID_NAME', ...
That is what is done by ZW3D.
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