Model export as dxf

[amanda]

Hi,

I have recently updated to version 1.0.3 build 1832. We use the model export in the dxf format to generate digital elevation model in Autocad Civil 3D. In the old version the dxf model export generated 3D triangle surfaces. In the new version the format is changed. I can still open it in Autocad but I don't recognize my model at all. How can I export the triangles as 3D surfaces in dxf in the new version of photoscan?

Some help would be great, thanks
amanda

[3DFranz]

Hi Amanda,

save your Project in version 091. Open it with 091 and export as dxf there.
Seems like the dxf export is bugged in 103.
I had few days ago the same problem.
But if you want to generate a Elevation model, why do you use AutoCad and the Model export function.
Export via Agisoft a DEM as tiff. Import the DEM via Autocad and generate your Contour lines or what ever there. Exporting your Model as dxf,..takes much too much triangles. Your Autocad will go down with >5 Millions triangles.
Hope that helps.

[Viking69]

I am having the same problem with the latest build. The triangulation is a mess. Will reinstall the older version.

[Alexey Pasumansky]

Hello all,

Thank you for reporting the problem. In the version 1.0.3 we have really changed the representation of the exported DXF model from 3D-faces to polyline mesh, as it better describes the original PhotoScan model.

So could you please specify what problems you are facing with such model representation in DXF format? Will "Explode" function in Autocad work to split mesh into individual faces?

I've opened DXF file exported from PhotoScan 1.0.3 in Autodesk DWG Treview without any problems:

[amanda]

Hello all,

Thank you for your respond. I think that the problem occurs when the model has more than 40'000 or 50'000 triangles. I will now downgrade to my old version until this bug is fixed.

To 3DFranz: Thanks for your tip, but if the surface is real 3D and not 2.5D the DEM isn't working anymore. Means that i can't model very steep or overhanging surfaces with the DEM export.

[Alexey Pasumansky]

Hello Amanda,

Thank you for this information. I've performed my check on lower number of faces (about 20 000) and now I'm testing bigger model.


Seems like there's a 32767 limit for vertices in such polyface mesh representation: http://www.deelip.com/?p=14
We'll try to find the way to solve this issue on our side as soon as possible.

[Alexey Pasumansky]

Hello all,

Please try PhotoScan version 1.0.4 build 1845. DXF export should be fixed.

[Pixel UAV]

Hi Alexey,

I recently have come across this problem as well.  I have found that AutoCAD can handle the .dxf but many other programs can't, such as BricsCAD and 12d.  Is it possible to that Photoscan could export in the old format of .dxf so that all programs can handle it?

Cheers,
Cam

[Alexey Pasumansky]

Just a small update on this topic: in the next version there will be a possibility to choose the internal representation of DXF format: either 3D faces (like in old PhotoScan versions) or polyline (like in latest release).