Anyone had an experience of the 3D registration between IFC model and its relevant 2D drawing PDF?
In the software implementation group in buildingSMART Japan is now trying to define the common specification of the position matching between an IFC model and its 2D drawing PDF exported from a BIM software.
The 2D drawing PDF may contain the origin point, projection direction, and paper plane, to match the IFC 3D model and 2D drawing.
For example, a BIM software could export the 2D drawing PDF with the parameters of vector and position information embedded in the particular layer with in the exported PDF. Any IFC viewer can utilize the parameters to match the position and direction between imported IFC 3D model and its relevant 2D drawing PDF.
The relationship between IFC data and 2D drawing could be realized by proving IfcProject.GUID which is added into the embedded parameter in the PDF.
As you know, BIMx has already realized the integration of 3D model and 2D drawing. We would like to realize the same function by openBIM ecosystem.
@Yoshi_bSJ,
I cannot suggest sth straightforward way to IFC --> PDF conversion, but I can refer the path IFC --> SVG --> PDF for your purpose.
If you would like to build a solution yourself, I think the most relevant library is the IfcOpenShell; or IfcConvert should be ready to convert your IFC to SVG file with its pre-built configs. Then you can utilize many libraries in different languages to convert your SVG to PDF with all the data you need. As you may know, SVG is in XML format and you can insert as many tags as you want to make your 2D drawing rich enough. An example drawing path with some extra data (guid, area, zone name) can be like following. <g guid="0BTBFw6f90Nfh9rP1dl_3P" type="IfcSpace" area="2.5" zone="elec" <path style="stroke:#333333; fill:#FFFFFF; stroke-width: 0.01px" d="M2.573999899999996,7.553999899999972L2.573999899999996,9.725000100000015L4.030000099999998,9.725000100000015L4.030000099999998,7.553999899999972L2.573999899999996,7.553999899999972" /> </g>
Although it is an old post, check this link to see how to generate cross-sections, and here is the python module of IfcOpenShell
Dear Mehmet, the question Mr. Adachi (@Yoshi_bSJ) asked is a little bit unclear.
Do they want to show IFC (3D geometry and its related data/information) on 2D PDF? Like what some solutions like Dalux or even Autodesk BIM360 do? (which is based on converting 2D PDF/Plans to SVG)
Or are they thinking about a CDE? based on PDF and IFC? In general, an information system which supports different formats like IFC and PDF, etc. (as an integrated solution)
It would be great if IFC could handle the information needed to transfer the mapping of drawings and model.
At the moment this is done automatically in Dalux CDE via BIM authoring software plugins or recreation of the data in Dalux when using IFC.
References between drawings are also of great value, however this can be recreated automatically.
I agree on above approach with SVG for model-cuts.
Maybe the cuts could be embedded in the IFC?
However, model-cuts are not necessarily drawings and drawings in the BIM authoring software are maybe located in the model, but can contain more detail. It can be tricky.
Still, most BIM authoring software have this data and it should be possible to transfer standardized.
It seems that both @Foldager and @ylcnky have worked in this area and hope they help you in this way.
In the near future, we will work on Page Layout, which PDF is a kind of.
Yes, the automatic IFC to 2D plan conversion could be one of solution to combine the 3D model and 2D plan.
The reason why bSJ chapter is trying to do 3D position matching between IFC model and 2D drawing PDF is that the 2D drawing document contains the additional information such as annotations, symbols and perhaps some notations for the particular purpose, i.e. comments for building code checking.
For example, Solibri can import the 2D PDF, and the paper space origin seems to be set at the center of Solibriâs 3D model origin. If this origin matching is done by automatically, it would be great.
As we know one of the most important issues in the industry is lack of âenough (not minimum)â data/information mounted on 2D-3D objects
However, when the PDF is popular in the industry and even is a standard, I think it doesnât answer today needs
This is why I think âPage Layoutâ is a better answer
However, I think as MVP, itâs better to start from PDF approach which you follow
Regarding âbuilding code checkingâ
I think the built Environment Industry is one of the messy industries with:
1. a lot of file formats 2. and less structured data
Which I think if we want to have good solutions should focus on these two issues.
Even IFC inherently has some vital issues, for instance, IFC XML doesnât have a mechanism for rule checking, thisâs why I asked this question:
Thank you @ReD_CoDE
There will be expected the new better 2D graphics methodologies in the future, such as âPage Layoutâ that you mentioned.
At the moment, 2D drawing PDF is one of common digital way of the communication between the building code check agency and applicant in Japan.
bSJâs digital building code check working group defined the roadmap for IFC utilization by the building code check organizations.
Current situation: Building code check by 2D drawing.
Interim goal: Building code check by 2D drawing and IFC 3D model as reference information. IFC Viewer will support the IFC 3D model and 2D drawing position matching.
Future goal: IFC based Building code check with automatic code checking solution.
For the first step, they are working on making the specification of the position matching solution between IFC model and 2D drawing PDF. There was the presentation of this theme at the industry day of buildingSMART Tokyo Summit 2018.
They are planning to show some updates at the bSI Beijing Summit next fall 2019.
Last night in a Silicon Valley forum I saw an MVP that caused I think again about your approach.
As I know at the moment Bluebeam is a leader to providing PDF solutions in the (Digital) Built Environment Industry and mainly SKANSKA has focused on PDF-based solutions and use their solutions
Thatâs not very important just caused I think again about the (digital) built environment industry
What I see in BIMx solution I see in Autodesk Revit 2020 too. But I donât think it is what youâre looking for.
It just adds PDF as a Page Layout layer [Vector] (which PDF is inherently a Page Layout File too) under your BIM model. But I donât think it has a fully coordinated approach.
For the first milestone that you mentioned:
Building code check by 2D drawing
There are two important topics:
Existing PDFs that contain âData+Information+Model (Normally 2D models from paper scans)â which needs âdata/information extractionâ
This is why the majority of solutions are based on SVG, because 2D plans as graphics in PDF stored as vector formats.
3D registration between IFC model and 2D drawing PDF: which needs PDFs generated with these requirements in mind. This means that this solution wonât work with existing PDF files in companies as silos but will work with PDFs that will develop on bSJ or bSI based on integrating PDF structure and IFC structure.
As I see in the industry those countries who have national digital projects mainly have focused on the first approach [1] but think about the second one [2] too
Basically, we are storing views as IfcAnnotation with conventions for view extents. There are also a series of SVG metadata used to link back these 2D outputs with the IFC dataset.
I offer a suggestion, the âTGNâ definition that I specify (the spec is free and open for everyone) as a next gen concept that includes and extends the first gen drawing-model fusions that have happened since 2012. TGN can redefine the drawing creation process at time of creation in all modeling apps, and also would support (T2, from the TGN spec) entry points for legacy drawings, inclusion of which may use the methods currently in dev now (IFC Japan), but with enhanced viewing experience through the built-in camera rig and other controls.
The TGN specification offers ALL software developers via TGN development, new opportunities to redefine and :
evolve the way users create drawings within models of any kind
within legacy modeling apps
within metaverses and digital twins
within new apps developed for this purposeâŠ
evolve the way users view drawings within models, with viewing enhanced by cinematic camera rigs and other controls
evolve and increase the value of models. TGN next generation user interactions within modeled worlds give users the power to create, clarify, and share, their own expressions of articulated focused attention within models. This increases the value of models by increasing their embedded interpretive quality. This increases model utilization and user uptake through embedded support for effective development of understanding of complex models among users of all kinds.
evolve the way users SHARE expressions of articulated focused attention within models, across modeling apps, formats, platforms, and metaverses, with TGN rigs created in any app expressible when shared, with reliable fidelity in other apps.
evolve the way legacy drawing formats are incorporated and upgraded to the modernized in-model TGN experience
I started working on this stuff a long time ago. I had the idea as a BIM software user in architecture firms since the 90s that drawings should appear at their true orientation within models automatically. By 2007 I formulated that in a little proposal document and shared it with my favorite software company. A few years later I was working for that company as part of the development team that designed, developed and first commericalized automated drawing-model fusion. This was released as features within Bentleyâs MicroStation in May 2012. I keep some examples on my page here: Earlier Innovations (2012) â [TANGERINE]
Since then automated in-model drawings fusion developed independently at 6 other software companies that Iâve seen.
That wasnât enough for me because to me it is obvious that the first gen drawing fusion work is step 1 of a much more significant evolution. After a few years, 2018, 19, and 20 working in other areas, this year Iâve come back to this evolution in user expressions of articulated focused attention within models. So this year Iâve been able to work on these ideas again. I completed the TGN spec (in itâs current form; I invite everyone to mark it up and improve it), which I give away for free to anyone who wants it, along with some supplemental discussion videos and a partial demo.
Download links, demo, and more discussion are here Letter from a reader â [TANGERINE] My invitation is completely open for anyone to use the spec as they wish, and anyone who would like my assistance in such projects is more than welcome to call me.
Great Idea Rob! Which major software developer picks up the glove? What other initiatives cooking behind the scenes? After all, something building smarter can with 2D incoporated. Personally it would love to see some vision or movement into bringing the DXF format to become open standard. I have been told that the true story is that Autodesk âownsâ it. What else is the OpenCAD format? Or why is there nothing like Georeferenced PDF anywhere in AEC land? Still major gaps to bridge in my opinion. And this will stay if the industry just keeps focussing on a 3D modelled houseâŠ
