Exporting without hidden geometry

azz00 · 18 Feb 2012, 08:52

Hi everyone,

I am currently studying Architecture and I have built a quick site massing model on Sketchup. Now that I have done this I wanted to put it through programs such as Ecotect and Vasari. However, because I used the sandbox for the gradient of the site, the model looks a complete mess on Ecotect because it has exported the hidden geometry as lines?

Is there anyway to export the model from Sketchup without the hidden geometry? Or anyway of smoothing the lines in Ecotect?

I have tried exporting in a number of different formats but all with the same results.

Thanks!

Gaieus · 18 Feb 2012, 09:16

Well, that geometry is needed to maintain the curved surfaces. It's actually not "hidden" but "softened" geometry but anyway, if you leave that out, you will lose the facets they support.

I do not know this Ecotect software but you need to find a way to soften this geometry there. What format are you exporting in?

azz00 · 18 Feb 2012, 09:27

Yeah I see what you mean. I have tried exporting in .3ds .obj .dxf

Gaieus · 18 Feb 2012, 09:30

In 3ds export options, there is a "weld vertices" (or what) checkbox.

TIG · 18 Feb 2012, 10:03

Exporting in OBJ for example will ignore hidden edges that are NOT needed to define a face.
What you describe is actually the smoothed edges that are needed by the face[t]s that combine to make the surface mesh.
Most exporters also triangulate faces, as app's like renderers expect this.
Most exporters contain 'vertex' data that ells the importing app if an edge is smoothed or not.
So If I export as OBJ to a renderer it will know what edges are smoothed and what are 'sharp'. Renderers usually only display faces so the edges are not shown except in how they impinge on a 'mesh' and thereby change how the faces look when rendered.
The code used by other importers can be less precise.
For example if you are reimporting an OBJ file [e.g. using Fluid Free Importer] into a SKP then edges that were originally smoothed may well appear 'solid'...
This could be the case with your own app's importer...
Are there any settings to cover 'smoothness' ?
Here's some examples:-
Original SKP with different mesh smooth/hidden edge settings: Exported as OBJ and Rendered [low-res Octane] edge settings are important in how the surfaces get represented - this shows that edge 'smoothness' settings are passed in the exported OBJ file: The OBJ file reimported into SKP, looses all edge settings [note the OBJ's triangulation of the original quad facets]:

azz00 · 18 Feb 2012, 14:27

Cheers for the replies. Looks like I am going to have to try and find a way to sort it out in Ecotect!

TIG · 18 Feb 2012, 14:53

Skimming through Ecotect someone raised the same question in 2005!
You can't hide smooth edges in the imported data-set or presentations - as far as I can tell...
That's typical of 'AutoDesk' issues - it'll analyze the kneecaps off a gnat, but it can't do the easier stuff !

azz00 · 18 Feb 2012, 16:06

Ha, I could not agree more!