Techdraw - no center snap points are shown

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wandererfan
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Re: Techdraw - no center snap points are shown

Post by wandererfan »

71GA wrote: Mon Aug 05, 2019 6:26 am I am trying to dimension a rod in a Techdraw with a bunch of screw holes, but i can't, because there is no snap points in the middle of the circles.
Thanks for your feedback on TechDraw. Anything that prompts review is welcome.

I had some time this morning to go through your posts and comment on some of your concerns.

None of my comments should be taken to imply that TD is perfect as is. It has a long way to go.

Thank you for the templates.

wf

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"I am trying to dimension a rod in a Techdraw with a bunch of screw holes, but i can't, because there is no snap points in the middle of the circles. "

>>Arc center marks can be used in exactly the same way as Vertices ("snap point").
HoleDimensionedToCenterMarks.png
HoleDimensionedToCenterMarks.png (16.92 KiB) Viewed 1429 times
"But please make this center mark into a snappy point and make it visible from any angle and for hidden circles/elipses as well. You should make center mark optional like horizontal/vertical center lines are."

>>in a side view the program only sees a line. It doesn't know that the line represents a circle on its side, so there is no way to mark the circle's center. That's why cosmetic features were added.
HoleLocationByCosCenterLine.png
HoleLocationByCosCenterLine.png (19.37 KiB) Viewed 1429 times
"Putting a snapping point in a center of a circle is an universal solution opposed to quadrants (attachment) and crap that v 0.19 presented as a fix for the problem. Please start solving problems at their root. If you ask me v0.19 presented mediocre solutions which again fail in specific situations. And THAT is a programming time wasted..."

>>I doubt there is a draftsperson anywhere that puts a dot on the page to mark an arc center. The "+" is a universal convention and serves to differentiate the arc center from edge endpoints.

>>The quadrant and midline "crap" was put in because of requests from users (the ones I don't listen to) of the old DrawingDimensioning workbench. These features really don't figure in your issues.

"Let me dimension object how I want it and sometimes dimensioning hidden edges saves you a ton of problems!"

>>You can dimension hidden edges. Hidden vertices are not displayed. I believe you are the first one to request this.
DimOnHiddenLine.png
DimOnHiddenLine.png (23.23 KiB) Viewed 1429 times
"I am currently unable to dimension (marked with ???) element which has diagonal holes (because there is no points in the middle of the circle as previously exposed). With one hole I had luck that seam was visible after the section, while with the other hole seam wasn't visible so I wasn't lucky and I can't dimension that hole. If you would put a point in the middle of the circle the problem would be completely gone even for diagonal sections... And that is an universal solution. The quadrant that was created in v0.19 is not. "

>> as explained above the program has no way of knowing that a line represents an edge-on circle. The way to dimension these holes is by adding a cosmetic centerline to the bore or by using a Section view.
DimensionHoleFeatureWSection.png
DimensionHoleFeatureWSection.png (19.72 KiB) Viewed 1429 times
"I added the primitive line in the drawing (like saso suggested), but it doesn't show in TechDraw even after refreshing."

>> did you add the line to the View Source property? If not, TechDraw has no way of knowing that you want the line to show on the drawing.
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wandererfan
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Re: Techdraw - no center snap points are shown

Post by wandererfan »

71GA wrote: Sun Aug 18, 2019 3:14 pm I tried setting a primitive line as you all suggested (I did it like saso suggested and not in sketcher), but it doesn't work. I don't know why. Here is my screencast and my minimal (non) working example (FCStd).
The Construction Line was too small to see, so I made it longer.
ConstructionLine3D.png
ConstructionLine3D.png (19.97 KiB) Viewed 1425 times
The Construction Line has to be part of the View.
ConstructionLineInSource.png
ConstructionLineInSource.png (28.34 KiB) Viewed 1425 times
Then you can do this.
DimensionToConstructionLine.png
DimensionToConstructionLine.png (27.13 KiB) Viewed 1425 times
Attachments
minimalConstructionLine.FCStd
(150.28 KiB) Downloaded 46 times
user1234
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Re: Techdraw - no center snap points are shown

Post by user1234 »

I was looking on the drawing, there is somthing wierd. When i recompute the drawing, all section elements vanshies. But all settings are right. There is more going on. I look tomorrow on it.

Greetings
user
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_vanished_sections_elements.webm
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71GA
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Re: Techdraw - no center snap points are shown

Post by 71GA »

wandererfan wrote: Sun Aug 18, 2019 8:44 pm Then you can do this.
DimensionToConstructionLine.png
I managed to include the construction line in a side view (view that you get when you press key 6) like you did by choosing (a) my object and a (b) construction line in tree view and then I inserted the TechdDraw standalone view. No problem.

Where it gets tricky is when I want this construction line to show in the section. So if I remain in the side view with both objects chosen and instead insert only a top view of the "multiple linked views" which I then section I get an error (attachment).

So how do I get the construction line to show in a section? Maybee this doesn't work yet?
Attachments
Screenshot from 2019-08-19 06-39-19.png
Screenshot from 2019-08-19 06-39-19.png (93.42 KiB) Viewed 1404 times
user1234
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Re: Techdraw - no center snap points are shown

Post by user1234 »

Hello!
71GA wrote:
There is something really buggy. The section only gives results when Hard Hidden == true . Means that the section will not performed. But the coordinates are correct (x=-3735.0000). My drawings (with sections) all work.
_section_fails.webm
(342.15 KiB) Downloaded 44 times
done with:

Code: Select all

OS: Debian GNU/Linux 10 (buster) (X-Cinnamon/lightdm-xsession)
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.19.17798 (Git)
Build type: Release
Branch: master
Hash: 7e60631239109c632a8f6cca83f6e7e5502e43a1
Python version: 3.7.3
Qt version: 5.11.3
Coin version: 4.0.0a
OCC version: 7.3.0
Locale: English/UnitedStates (en_US)
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user1234
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Re: Techdraw - no center snap points are shown

Post by user1234 »

That the section is not working have something to to with the placement. When i delete the x coordinate and give the same value the x coordinate again and recalculate it, it works.

I do not know why the line do not work. I tried many workarounds, but nothing works. I think that the OCCT is to weak for that, because it gives me always fuse errors in TechDraw. But the cometic line (in the 0.19dev) works pretty neat. I know, you have not 0.19dev yet. Have you maybe installed a PPA? Is this possible in Debian? Sorry for that, but i can not help you.
_cosmetic_line.png
_cosmetic_line.png (335.63 KiB) Viewed 1362 times
Greetings
user
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