ArchSite Compass

[regis]

I would suggest renaming it as "orientation" for where you have put "visualize True North" and where it says , true false. You can say "project north, or True north". I think that makes more sense architecturally.

[furti]

renaming it as "orientation"

Thanks for the hint. I updated the property Name now. The Compass is also scaled now depending on the projected Area of the Site. So one can also see it for Pretty big sites.


@yorik
Also created a pull request for it (https://github.com/FreeCAD/FreeCAD/pull/2111). Feel free to merge it if you think this is some useful feature

[bernd]

At work we gone use the following work flow.

- the project will be moved from real coordinates near to the coordinates origin. Our CAD can make this automaticly. Export is possible allways in virtual moved coordinates or real world coordinates.
- the project is not (really not) turned into a North direction.
- The drawing screen of the CAD is turned into North direction, which means the draftsmen can work as it would be in north but the project is not turned.
- Only with this method it is possible to easy export the project in real coordinates and moved virtual coordinates.

For any BIM-work flow with other offices (Solibri or BIMCollabZoom) we gone use virtual moved (not turned) location of the modell.

bernd

[paullee]

Hi, I had been puzzling how this 'real' coordinates issue should be handled in FC.

A few problem, but no solution ATM:-

- In AutoCad, we used to draw everything in real World Coordinates

- AutoCad has Block and Xref so it is easier to draw something 'in its own coordinate system; then put it (assemble / rotate ) in real World Coordinates

- AutoCad has UCS / Coordinate System which you can customise it, move 'origin;, rotate axis...

- In FC, attempted to do similar but it is very difficult as ther seems no similar 'block' . Xref' feature, UCS ...

Am I missing something.

BTW @Bernd I think I do not fully understand your workflow, has some simple file for reference?

Thanks.

[bernd]

Thats the workflow we do in Nemetschek Allplan. What is not well described?

I am with you, I do not know yet how to handle the world coordinate problem in FreeCAD.

Do you really work with these huge coordinates in AutoCAD ? Do you ude AutoCAD not Revit? Do you do 3D building models in AutoCAD?

[thschrader]

I am with you, I do not know yet how to handle the world coordinate problem in FreeCAD.

We have the same problem. We get terrain data from the geotechnicians in world coordinates.
For sites in switzerland the global origin in FC is hundreds of kilometers away from the cad model.
So we type the terrain points manually in excel and transform the origin after choosing a
reference point in the cad model. This only works because we have less then 100 points.
Using a laser scan of the terrain with 100000 points would be impossible...
EDIT: example
RP is the choosen reference point of the building transformed to the FC-origin (= green dot).
The colored lines is the "walking path" of the geotechnician.

iso1.JPG (67.94 KiB) Viewed 1317 times

RP1_Lage_Koordinatensystem.JPG (83.49 KiB) Viewed 1317 times

[paullee]

Hi, any idea about 'World Coordinate' issue?

[yorik]

My opinion is that we should be able to model in FreeCAD the way we see fit, project by project. If you have a "rectangular" project, the most convenient way to model it would be to have the rectangle aligned with the global X and Y axes of FreeCAD, and, probably, have it placed at a meaningful position, for example one of its corners at the (0,0) point. After all, people modelling other things (mechanical parts, etc) also rotate and place models the more convenient way for modeling... Why couldn't we do that too

One can of course do that with "additional coordinate layers" (UCS in autocad), and therefore model in real-world coordinates, but have it displayed in user-defined coordinates, but it's never as handy and powerful as having your model directly aligned with global coordinates. And I don't know for you guys but I find working for ex. with App::Parts in BIM/Arch models is a bit awkward... You quickly loose track of real position of elements. That's basically why I went against it with BuildingParts.

Then all we actually need is to say "the (0,0,0) point in FreeCAD corresponds to world coords X and Y, and direction (0,1,0) in FreeCAD has XXX degrees difference with true north)" and anyone would be able to place the model correctly in the real world. We still need to look at the proper way to export that in IFC.

Also, the Arch Reference object is very handy to solve these things. You can model for ex. a site with real-world data, and reference it in a BIM model and translate it ot the project origin...

[furti]

Hi, any idea about 'World Coordinate' issue?

I don't think I'm the right one to decide how this could be solved. I don't work in the architectural field and have no experience with other Architectural CAD applications. So hard for me to suggest something

I modified the Arch Site a bit because:
- Modelling a house is way easier when one can use the global axis as reference Points
- But when Looking on the finished model, it is Pretty hard to see where North (or more important for me South) would be in the real world.

When Looking on the model Positive Y Always feels like North for me. So I decided to give the Arch Site a Compass so that one can see where True North is located. After some discussion in this thread I extended the Site so that it could calculate the "Declination" property on the fly and it can rotate the whole model so that the True North aligns to the Positive Y axis.
This makes it easier for me to see how the Building will look in real life

If this does not make a lot of sense for a professional Architect it is totally fine for me

So we type the terrain points manually in excel and transform the origin after choosing a
reference point in the cad model. This only works because we have less then 100 points.

I think your use case could be implemented either as a standalone macro or in the Arch Site directly. I think of importing the geometry as it is (a few hundred Kilometers away from the origin in FreeCAD) and give the Arch Site a "Reference Point" Vector, when set it will transform the shape so that the "Reference Point" Matches the Origin.


I pretty much like @yorik's idea. Simply model the whole Thing like it is best for you. Use the origin and the global axis or not. And afterwards set the offset Transformation somewhere and use this information where the world coordinates have to be used (Exports, Techdraw Pages,...).

The offset angle is already in the Arch Site. Adding a Reference Point would give us all the Information required to calculate the real coordinates on the fly.

[paullee]

Hi @Bernd, I am just a bit confused by the term virtual moved coordinates, virtual coordinate ... ; in any rate, it seem a number of people face similar problem.

@Yorik's suggestion of using Reference maybe the most easy solution, I haven't tried. One problem I faced is that when the model is at some real world coordinates exported to IFC, IFC viewer is reluctant zooming in the model..

Another Suggestion to Consider?

@Furti reminded that there is Longitude Latitude, NorthDeviation (? Declination), Origin Offset in the Arch Site.

[EDIT] Or Do it with Compass?

Though I think this is for SolarDiagram originally ? (I can't use it as found nothing in Fedora), could this be adoption to read the 'real world coordinates'... ?

- FC model drawn in convenient way against the FC axis / origin : The origin is a reference point
- The Arch Site Longitude Latitude, NorthDeviation, Origin Offset are set, with the Origin / Rotation correspond to the real world coordinates
- Now there is a "Master Switch" to turn on, then 'Coordinates' returned by FC is adjusted / translated automaticly to reflect the real 'World Coordinates'