How to make a sketch usable as external reference ?

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DoubleHP
Posts: 14
Joined: Sun Mar 05, 2017 6:11 pm

How to make a sketch usable as external reference ?

Postby DoubleHP » Sun Mar 19, 2017 4:19 pm

Hello.

See link to file at bottom of this post, or try this one:
http://dl.free.fr/sNbW6TIwN

I drew a sketch. It's a set of references for future uses. To be usable as external from other works, it needs to become a solid. I have tried half a dozen things on it, and all fail for various reasons. https://www.youtube.com/watch?v=5W44Kh1gkUQ&t=623s explains most of them. Then map is about 100m large; so I intended to give all elements a 1mm thinkness, what should be an acceptable "error" for all later uses.

The real work is Base_70, but, I have also generated Relations-Remarquables for fast work on a lighter sketch.

I have met missing coincides even on fresh projects with as few as 7 lines; as soon as lines are not strictly vertical or horizontal, missing coincidences are un-avoidable. Those MC prevent from applying most tools from the PartDesign WB. Extrusion fails, for various reasons. Rulled surfaces can not be used (if I ever need to rectify the base plan, having to manually apply the same changes to the copy-sketch would be PITA) and does not produce solids anyway (see youtube link). Sweep failed on much simpler sketches.

I have spent no less than 6h on trying to fix the missing coincidences; fixing them produces duplicate constraints; removing the dups produces MC again.

Most of these lines are "one side of a wall" (there are 4 exceptions).

I tried to elevate walls from that sketch (1mm height, 1mm large, would do what I need). Produces walls on less than 10% of the lines.

On top of this, when I can use it as external, I want, at least, to be able to draw rooms in each building (one sketch per room). And if possible, add 3D considerations (each room sketch should be put at correct heigt (each floor contains room at 4 different elevations), and follow the base of the building if I ever adjust it - thus the need of external), and, of course, handle several floors (rooms on top of each other).

Also, I would like to be able to measure distances from within this sketch without having to enter edition mode.

I had tried to enter this plan using Draft WB, but, it seemed inapropriate.

Thanks for help.
Attachments
Propriete_70_forum.fcstd
(67.24 KiB) Downloaded 2 times
Last edited by DoubleHP on Sun Mar 19, 2017 5:51 pm, edited 1 time in total.
DeepSOIC
Posts: 4495
Joined: Fri Aug 29, 2014 12:45 am
Location: Saint-Petersburg, Russia

Re: How to make a sketch usable as external reference ?

Postby DeepSOIC » Sun Mar 19, 2017 4:59 pm

Hi!
Missing coincident is a misleading error, and it by no means can prevent the sketch from being padded/extruded/revolved. To make edges connected, you should bring the endpoints to within 1e-7 mm, and it doesn't matter if you use coincident constraint to achieve it, or tangent, or dual point-on-object, or whatever else.
DoubleHP
Posts: 14
Joined: Sun Mar 05, 2017 6:11 pm

Re: How to make a sketch usable as external reference ?

Postby DoubleHP » Sun Mar 19, 2017 5:14 pm

Seems unrelated, but I have isolated a bug which, if solved, would be a solution to my problem:
Link below or https://drive.google.com/a/demaine.info ... sp=sharing
one sketch, 4 lines, when I do a Arch / Walls, I only get 3 walls. That file has no missing coincidence. One approach would have been to build 1mm height and 1mm thick walls, in order to produce a solid that would have edges usable via Externals. Was said it fails on my big file because I have too many elements; here, it fails with just 4 lines !!!

OS: "Gentoo Base System release 2.2"
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.16.Unknown
Build type: Release
Python version: 2.7.13
Qt version: 4.8.7
Coin version: 3.1.3
OCC version: 6.8.0.oce-0.17

Same bug with AppImage
Attachments
zzz02.fcstd
(3.14 KiB) Downloaded 1 time
Last edited by DoubleHP on Sun Mar 19, 2017 5:52 pm, edited 1 time in total.
DeepSOIC
Posts: 4495
Joined: Fri Aug 29, 2014 12:45 am
Location: Saint-Petersburg, Russia

Re: How to make a sketch usable as external reference ?

Postby DeepSOIC » Sun Mar 19, 2017 5:19 pm

None of your download links function for me. One says 404, the other says I don't have permission. Please upload file to the forum if it's below 1 MB.
DoubleHP
Posts: 14
Joined: Sun Mar 05, 2017 6:11 pm

Re: How to make a sketch usable as external reference ?

Postby DoubleHP » Sun Mar 19, 2017 5:55 pm

I edited both posts to add files. First service should be my provider special sharing service; second is google, and worked for some guy on IRC. Long time ago, Internet used to be a universal place where the geographical location of an IP only affected the download rate, not the possibility to access a file. But all good things must end some day.
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NormandC
Posts: 12071
Joined: Sat Feb 06, 2010 9:52 pm
Location: Québec, Canada

Re: How to make a sketch usable as external reference ?

Postby NormandC » Sun Mar 19, 2017 8:35 pm

Salut DoubleHP,

(Vu le nom de tes fichiers, je suppose que tu es français ;) )
(Considering your file names, I'm assuming you are French)

DoubleHP wrote:worked for some guy on IRC.

LOL so I'm just "some guy", that's though for the ego :lol:

DoubleHP wrote:Was said it fails on my big file because I have too many elements; here, it fails with just 4 lines !!!

Maybe I was mistaken in blaming the number of objects on the failure to create a Wall.

What I now think is that the Arch Wall utility cannot deal with a corner that has more than two edges. Your zzz02.fcstd file has 3. And notice that the one line that is discarded is the third line joined to the corner.

As for your more general problem,
DoubleHP wrote:I drew a sketch. It's a set of references for future uses. To be usable as external from other works, it needs to become a solid.

It is certainly impossible to create a solid from either of the sketches in your Propriete_70_forum.fcstd file. In fact, I don't think the Arch workbench was ever designed to work with a massive "master sketch" that way. It was initially designed to work with Draft geometry, and Draft objects are always separate (Line, Polyline, Arc, etc.) so it is easy to only select the individual objects you want when creating walls.

I'm mostly using the PartDesign workbench, I'm a bit ashamed to admit that I still haven't made the time to properly familiarize myself with the Arch workbench work flow. But when looking at the Arch documentation and tutorials, I doubt there's a way to do what you are asking in the current 0.16 release.

In 0.17-dev there are huge changes being done in the PartDesign workbench. A new structure is being implemented with new "Part" and "Body" containers that have powerful properties to manage inter-links between objects, including sketches. I know that Yorik, the developer of the Arch & Draft workbench, is following these developments with interest, and is evaluating how to use these new features in his Arch workbench. It may take a while before seeing anything though, as work on PartDesign's new structure is still ongoing (at a rather apparent slow pace I might add, as there is only one developer working on these changes).

The Body container is exclusive to PartDesign and will contain only sketches and PartDesign features, but the Part container can contain any type of objects.

I made a quick test using the latest freecad-daily build based on 0.17-dev. With your Propriete_70_forum.fcstd file open:

  1. I created a Part container from within the PartDesign workbench.
  2. In the Model tree, I dragged the Base_070_relations_remarquables sketch into it
  3. Switching to the Sketcher workbench, I selected the XY_Plane under Part/PartOrigin and clicked on Image Map sketch to face;
  4. I selected the sketch I had just moved to the Part, then clicked OK;
  5. In the Sketch attachment dialog, I selected "FlatFace". These steps ensure that the sketch is mapped to the XY plane of the Part container.
  6. Still in the Sketcher workbench, I selected again the Part's XY_Plane then clicked on Create new sketch. Again I chose the FlatFace attachment mode.
  7. One thing that may be a bug: the Sketch is created outside the Part container. So I exit the Sketch edit mode, then drag & drop it into the Part container.
  8. I edit the Sketch again, and this time I can link external geometry from the Base_070_relations_remarquables sketch.
I believe this method allows for a master sketch work flow, but this is just a test, I have no idea if there might be problems with such an approach, because we are in unknown territory... For example, an Arch Wall created from the sketch is listed outside the Part container, and it brings the sketch with it; trying to drag & drop the Wall on the Part, the Sketch is no longer nested under the Wall.

OS: Ubuntu 16.04.2 LTS
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.17.10490 (Git)
Build type: None
Branch: master
Hash: 378f99f1b318202db3bc89b45d691a0376d07512
Python version: 2.7.12
Qt version: 4.8.7
Coin version: 4.0.0a
OCC version: 7.1.0
Attachments
FC017_Propriete_70_forum_normandc1.fcstd
(87.98 KiB) Downloaded 1 time
DoubleHP
Posts: 14
Joined: Sun Mar 05, 2017 6:11 pm

Re: How to make a sketch usable as external reference ?

Postby DoubleHP » Mon Mar 20, 2017 7:07 am

My brain has too few cells to be able to remember all names of people I talk to.

I had tried to attache a sketch to the face of various solids before writing this post, and in 0.16, all failed. Attaching works, but the attached sketch can not be used as external source before it has been used for any solid construction (pocket or extrude). Your point 7 is a detail mentionned in a few Youtube tutorial.

I am fighting on too many issues at the same time (including installation, portability, and rendering, bugs in the undo stack); I will give up.

Thank you, cheers.