TechDraw HLR parameters for section of a multibody

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gatlib
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Joined: Fri Nov 09, 2018 5:17 pm

TechDraw HLR parameters for section of a multibody

Post by gatlib »

Hi everyone,

I started to play with the TechDraw module (by the way, it's great that such a module actually exists...) and I'm struggling with an issue regarding the tuning of the HLR parameters for section views.
I didn't manage to find a set of parameter able to distinguish between:
- the hidden lines of geometry "behind" the cut plane,
- the interfaces between distinct bodies,
The visibility for both of them seem to be driven by the "Data/HLR Parameters/Hard Hidden" parameter and their thickness by "View/Lines/Hidden Width", see attached example.

I would like to display the contacting interfaces between bodies but not the hidden lines. Is this somehow possible?

Thanks!


OS: Debian GNU/Linux 9 (stretch)
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.18.15900 (Git) AppImage
Build type: Release
Branch: master
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Python version: 3.6.7
Qt version: 5.6.2
Coin version: 4.0.0a
OCC version: 7.3.0
Locale: English/UnitedStates (en_US)
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section.FCStd
(15.49 KiB) Downloaded 42 times
freedman
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Re: TechDraw HLR parameters for section of a multibody

Post by freedman »

I would like to display the contacting interfaces between bodies but not the hidden lines. Is this somehow possible?
Can you expand on what you want? If you want different lines then maybe a different view?
gatlib
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Re: TechDraw HLR parameters for section of a multibody

Post by gatlib »

Sure!
In section.FCStd I have two distinct bodies, touching each other.
In TechDraw, the view "View" shows the interface between the two bodies, as expected.
In the view "Section A-A", the interface is by default hidden, I want to show this interface.
However, I don't want the "hidden lines" (not generated by the interface but by other geometries) to have the same appearance as interfaces.
Is it clearer?
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wandererfan
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Re: TechDraw HLR parameters for section of a multibody

Post by wandererfan »

gatlib wrote: Wed Feb 20, 2019 8:10 pm Is it clearer?
I think I'm going to need a picture to understand.

Does setting "ShowCutSurface" to false help you?
Attachments
ShowCutSurface.png
ShowCutSurface.png (31.72 KiB) Viewed 1709 times
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wandererfan
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Re: TechDraw HLR parameters for section of a multibody

Post by wandererfan »

Just guessing, but how about this?
Attachments
sectionOrigin.png
sectionOrigin.png (3.47 KiB) Viewed 1706 times
freedman
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Re: TechDraw HLR parameters for section of a multibody

Post by freedman »

An issue with the gatlib view A-A, why isn't there a line between the two bodies? I could understand if there was one body but with two bodies I would expect a line.
Attachments
line_snip.JPG
line_snip.JPG (11.48 KiB) Viewed 1701 times
Last edited by freedman on Thu Feb 21, 2019 8:48 am, edited 3 times in total.
gatlib
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Re: TechDraw HLR parameters for section of a multibody

Post by gatlib »

Thanks for your answers, I think we're getting there! Sorry, I thought my problem was easier to explain, but my test file was apparently not as self-explanatory as I thought. To sum-up:

- No, "ShowCutSurface" does not help
- No, I do not want to move the section plane
- YES! I expect to see "a line" between the two bodies

I attach a little picture, in Section A-A, I would like to display (which is quite standard):
- The hidden feature of the top body as a dashed line
- The interface between the bodies as a solid line
I'm not able to set them independently.

Thanks for your feedbacks!
Attachments
section.png
section.png (16.9 KiB) Viewed 1681 times
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wandererfan
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Re: TechDraw HLR parameters for section of a multibody

Post by wandererfan »

gatlib wrote: Thu Feb 21, 2019 7:18 am I attach a little picture, in Section A-A, I would like to display (which is quite standard):
- The hidden feature of the top body as a dashed line
- The interface between the bodies as a solid line
:idea: :idea: :idea: !
So you've already discovered this:
using freecad-daily
using freecad-daily
gatlib_hardHidden.png (12.79 KiB) Viewed 1643 times
But you'd like to have this:
using modified code
using modified code
gatlib_unfusedSource.png (16.61 KiB) Viewed 1643 times
In the current code the Source shape(s) are fused together before doing the section cut. Sometimes this is required to get good results. Maybe there should be an option.
gatlib
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Re: TechDraw HLR parameters for section of a multibody

Post by gatlib »

[ Edit: woops, line removed, shouldn't have been posted! ]

Yes, I'd like the "unfused source" behaviour, using the modified code. Thank you very much wandererfan.
I actually think that the "unfused source" should be the default, but providing an option is ok.

I'm not familiar with the freecad source code (but not too scared by code in general), can this parameter be easily found/tweaked?
Last edited by gatlib on Fri Feb 22, 2019 9:25 am, edited 1 time in total.
freedman
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Re: TechDraw HLR parameters for section of a multibody

Post by freedman »

Look at the macros, you can learn to write them and set/reset almost everything.
Last edited by freedman on Fri Feb 22, 2019 5:15 pm, edited 2 times in total.
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