CompuServe Messages

#MicroStation to 3DS??

    26-Apr-95 11:23:31
Fm: Grahame Naylor 100013,1340
To: James M. Murphy 71165,1321
Murph I have been taking in a lot of uStation stuff recently, the biggest problems come from the Beta spline entity type which ( as you may imagine) is very popular for modelling ! The uStation operator can determine the segmentation of the resulting pline, pline-mesh or whatever before translating it but it is very easy to end up with adjoining parts with different segmentations and maybe a few glitches as well. There is probably room for an in-depth analysis of the ideal way to translate and I think it would be worth it, uStation 5 looks to be a very good modeller but it would need uStation and 3DS in the same for a day or so for trial and error testing. On the whole the problems are not really any worse than coming from ACAD, apart from one big whoopsy…. uStation can generate a polyface mesh entity with only _2_ vertices in the face, ACAD will accept this and even pass it on to .DXF but 3DS aborts the dxfin with an "Invalid ratsnest in DXF" error message. One test for this condition is that uStation will not read the .DXF back. Using Autovision to 3DSOUT bit by bit will detect the offending part but proceed with care Autovision is one of the worse ways around for getting a 3DS mesh. If this causes a major problem I have an Autolisp routine which will zap the offending faces ( it is not exactly thoroughly tested but does seem to work OK) let me know if you want it. Microstation 5 will output .DWG or .DXF I have mostly used .DWG out of uStation and then passed it through ACAD 12 as a sanity check before dxfing for 3DS. Microstation 4 only has .DXF out and causes far more problems where beta spline entities are concerned. Grahame