linked shape object is empty freecad что делать
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Union: Input shape is null + SIGSEGV
Union: Input shape is null + SIGSEGV
Post by Premik » Sun Sep 10, 2017 8:46 am
I have two Body parts. Each with one Sketch and one Pad. Please see the attachement.
The parts are in some strange state where they refuse any boolean operation.
Part/Union boolean:
Exception (Sun Sep 10 09:33:00 2017): Input shape is null
Part design/Union
SIGSEGV in opencascade (see below for the bt)
Re: Union: Input shape is null + SIGSEGV
Post by wmayer » Sun Sep 10, 2017 10:18 am
I am not familiar how PD booleans are supposed to work. But after playing a bit I also got a crash which shows a similar backtrace to yours. When checking this with the debugger then there is a null shape passed to BRepAlgoAPI_Fuse which of course is a bug.
What I did is:
* load your file
* activate the Long body
* select the Short body and press Boolean
As said above the body feature itself has a null shape but inside the algorithm there is no further validation check done and thus leads to the crash.
Re: Union: Input shape is null + SIGSEGV
Post by Premik » Sun Sep 10, 2017 10:59 am
Thanks. I didn’t know about the body tips thing. After seting the tips to the pads the part-union booleans seems to work ok. And the part-design one doesn’t crash anymore. At least in the version I have right now.
This also explains why copy-paste the shapes and recreating the pads+bodies solved the issue before. I think the tip is somehow set the the lates operation by default?
And this also solved another problem I had in a different project. Where I managed to get the tip set somewhere to the middle of the body. Good stuff.
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Post by hanzofactory » Wed Mar 24, 2021 1:14 pm
I urgently need to create a rendering and dimensionally accurate drawing of the model Knick’s Prosthetic Finger v3.5.5 found here: https://www.thingiverse.com/thing:1340624
I want to do it either in FreeCAD or by exporting a STEP file to Fusion 360 or other program.
But when I import the scad file (attached) I get this error:
15:10:17 Traceback (most recent call last):
File » «, line 1, in
File «/app/freecad/Mod/OpenSCAD/importCSG.py», line 119, in open
processcsg(tmpfile)
File «/app/freecad/Mod/OpenSCAD/importCSG.py», line 177, in processcsg
result = parser.parse(f.read())
File «/app/lib/python3.8/site-packages/ply/yacc.py», line 333, in parse
return self.parseopt_notrack(input, lexer, debug, tracking, tokenfunc)
File «/app/lib/python3.8/site-packages/ply/yacc.py», line 1120, in parseopt_notrack
p.callable(pslice)
File «/app/freecad/Mod/OpenSCAD/importCSG.py», line 480, in p_resize_action
p[0] = [Draft.scale(p[6],scale)]
File «/app/freecad/Mod/Draft/draftfunctions/scale.py», line 77, in scale
scaled_shape = scaled_shape.transformGeometry(m)
: Cannot transform null shape
Any help would be appreciated
Post by chennes » Wed Mar 24, 2021 1:49 pm
In the meantime, if it’s a possibility for you, can you use STL files instead?
Post by hanzofactory » Wed Mar 24, 2021 1:58 pm
In the meantime, if it’s a possibility for you, can you use STL files instead?
Sorry for not mentioning. I am using version 0.19.1 of FreeCAD (flatpak) and version 2019.5 of OpenSCAD. If it also helps my OS is Linux distro is Pop_OS (Ubuntu based)
I can’t use STL files because while rendering is okay, drawing (mostly regarding holes) isn’t (at least in Fusion 360, which is my preferred software) and is just as necessary.
Post by chennes » Wed Mar 24, 2021 2:42 pm
Post by hanzofactory » Wed Mar 24, 2021 3:00 pm
I have replaced the file with the one you attached.
It seems that a lot more objects are in the object tree now but I get a different error when importing the file:
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How to scale a solid object
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How to scale a solid object
Post by balden » Wed Aug 06, 2014 9:59 pm
First and foremost: many thanks to everybody involved in the FreeCAD community: developers, tutorial makers, forumers. This software is just fantastic: thanks for making such a powerful tool available to everybody.
I’m sorry to ask because this is probably a very basic problem, but I could not find a solution after searching for a while, so here it goes: I would like to scale a solid object but I can’t find the function to perform that operation. I found a chapter in the manual mentioning «box manipulators» for interactive scaling but this mention was in a grey frame labeled «obsolete» and I don’t see those manipulators appear when manipulating the object (I can rotate and translate, however).
Here’s my FreeCAD info:
OS: «openSUSE 13.1 (Bottle) (x86_64)»
Word size: 64-bit
Version: 0.15.3829 (Git) (Packman)
Branch: master
Hash: 234af5b27f997ee3e5dfa86e76ffe5521b31d532
Python version: 2.7.6
Qt version: 4.8.5
Coin version: 3.1.3
SoQt version: 1.5.0
OCC version: 6.7.1
Re: How to scale a solid object
Post by NormandC » Wed Aug 06, 2014 10:13 pm
FYI, in CAD as a rule you should not scale a solid, but model it to the desired dimensions. There are very, very few use cases where scaling an object is required: for injection mold tooling for example.
There is no specific GUI tool for scaling as of now, you would need to do in in the python console. But, the Draft Clone tool produces a linked clone of your original shape, and the Clone can be scaled in XYZ separately.
Re: How to scale a solid object
Post by balden » Wed Aug 06, 2014 10:33 pm
Re: How to scale a solid object
Post by NormandC » Wed Aug 06, 2014 11:26 pm
Part Slice
Part Slice
Содержание
Description
The Part Slice also known as Slice to compound tool is used to split shapes by intersection with other shapes. For example, for a box and a plane, a compound of two solids is created.
Above: the pieces were moved apart manually afterwards, to reveal the slicing
There are two commands to slice a shape: 
Part Slice apart and Part Slice to compound. They both create a ‘Slice’ parametric feature, that puts the sliced pieces into a compound. However, Part Slice Apart explodes the resulting compound into separate objects. «Slice to compound» is fully-parametric, and causes no trouble as the number of pieces changes. «Slice apart» will not update the number of objects as the number of pieces changes.
The output shape occupies the same space as the original. But it is split where it intersects with other shapes. The split pieces are put into a compound (or compsolid), so the object appears to remain in one piece. You need to explode the compound to get the individual pieces. If you want to access the individual pieces in a parametric way you can use 
Part Compound Filter for this purpose. For quick non-parametric access use 
Draft Downgrade.
The tool has three modes: «Standard», «Split», and «CompSolid». There is no selection form, they are predefined but can be accessed after the operation on the resulting slices level.
«Standard» and «Split» differ by the action of the tool on wires, shells and compsolids: if «Split», those are separated; if «Standard», they are kept together (get extra segments).
Compounding structure in «Standard» and «Split» modes follows the compounding structure of shape being sliced.
In «CompSolid» mode, the output is a compsolid (or a compound of compsolids, if the resulting solids form more than one island of connectedness). Compsolid is a set of solids connected by faces; they are related to solids like wires are related to edges, and shells are related to faces; the name is probably a shortened phrase «composite solid».
The overall action of the tool is very similar to 
Part Boolean Fragments, except only the pieces from the first shape are in the result.
Usage
A Slice parametric object is created. Original objects are hidden, and the result of intersection is shown in 3D view.
Tree structure of Slice
The Slice command creates a sliced object. In the following example a cube is sliced by a face.
The slice is created and each piece of it is united in a Compound.
Properties
̈Noteː Properties are accessible on the slices inner object, not on the result level.
Example
Creating a Puzzle
Note: Steps 5 and 6 can be done in single click using Part SliceApart
Notes
Scripting
The tool can by used in macros and from the Python console by using the following function:
Slice can also be applied to plain shapes, without the need to have a document object, via:
This can be useful for making custom Python scripted features.
Topological data scripting
Содержание
Introduction
Here we will explain to you how to control the Part module directly from the FreeCAD Python interpreter, or from any external script. Be sure to browse the Scripting section and the FreeCAD Scripting Basics pages if you need more information about how Python scripting works in FreeCAD. If you are new to Python, it is a good idea to first read the Introduction to Python.
See also
Class diagram
This is a Unified Modeling Language (UML) overview of the most important classes of the Part module: 
Geometry
The geometric objects are the building blocks of all topological objects:
Topology
The following topological data types are available:
Example: Create simple topology
We will now create a topology by constructing it out of simpler geometry. As a case study we will use a part as seen in the picture which consists of four vertices, two arcs and two lines.
Create geometry
First we create the distinct geometric parts of this wire. Making sure that parts that have to be connected later share the same vertices.
So we create the points first:
For each arc we need a helper point: