Import DWG/DXF's without tessellation!...?

[charlo]

It would be nice wouldn't it?

Been using Vectorworks and Stratavision for years with reasonable success, but always a tedious union. Vectorworks then made Renderworks which had promise but has turned ou to be anything but "highend". So now I've joined the big boys who use Maya. Yes a fantastic piece of software but not at the moment geared for the 2d - 3d modelling transitions common in Architectural work.

So we take our client's files in dwg or dxf format, clean them up and do basic modelling (the simpler repetative stuff) in VW then export them into Maya 5.0 in dwg format. This is where it gets sticky. You get all of your objects re-tessellated. Your extruded rectangles/polygons have been converted to a series of triangular surfaces. Not really a problem until you come to applying textures because selecting what were simple surfaces becomes pretty time consuming... well very time consuming. The tessellations are all individual surafces and can get pretty small.

If you are familiar with this issue perhaps you can help me;

a] find a file format or converter that overcomes this problem.

or

b] stop moaning and just model everything in Maya because there is no solution.

 

thanks for your attention.

[Tonsgaard]

hey...

 

Have you tried to set the ISOLINES in Acad to 1 when drawing the original model... This command is an expression for the tesselation of created objects...

Open the dwg file in acad and type 'isolines'... The standart is four, and unless you do organic modelling, thats way to much!

When modelling in Acad you doesn't see that the objects are tesselated so maybe it's not the import thats causing the prob.

 

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TONSGAARD

[charlo]

I'll try the isolines thing today, thanks. For the moment we are getting around the problem by going dwg->3ds->Maya. It comes in tessellated but you can tell maya to quadranulate the objects which gets rid of most of the triangles. Around non rectilinear gemetry it still tessellates, but at least there are not as many. unlike dwg's the 3ds import actually attaches the faces to their neighbors. In dwg they are all unnconnected ( so you have to modify 5 individual faces to raise the hieght of a cube!). A bit of a problem with the 3ds format is that it sometimes misses out surfaces, again around non rectilinear geometry. You end up having to simplfy your method of initial 3d modelling ... more rectangles to generate surfaces. It also loses the layers, unlike dwg.

It's no ideal yet, but we're making progress.

Also noticed some interesting things about the objects imported from Dwg and 3ds ...perhaps all imported cad not supplying texture information... into Maya. The default setting for 'render stats' on all of the imported objects had "reflections" and "refrations" switched off. Not good for global rendering I tell you. Down right annoying really. Makes them all render flat. But we know better now.