Number of segments in an arc

[barathd]

I'm so addicted to using Revit I did some industrial work (oilfield skids) with it. There is a fair amount of piping involved - Revit worked very well with one exception. Some of my circular items look very crude - small amount of arc segments. Can the number of arc segments be controlled within Revit?

Regards

[Dimitri Harvalias]

An arc is an arc in Revit, not a segmented curve. What kind of circular 'items' were you creating and how were they modeled?

[LRaiz]

Revit is engineered to deal mostly with objects of a building scale. When tessellating surfaces it makes an assumptions that objects are relatively big and their radius of curvature not too big. Thus curved objects of a small size might appear to be insufficiently tessellated. One can see that by modeling a coffee mug. User has no way of controlling tessellation coarseness. The decision to impose this limitation was made in the early days of Revit Technology Corporation and it allowed significant development simplification.

[BWG]

I had the same thing happen when modeling round tubes in a circle. I modeled them in a family for future use, but that should not have mattered. They looked fine in the model, but when they were printed it would come out segmented. We fixed it once, but it reverted back at some point and couldn't remember the steps to get it fixed again. Seems like we set the printed views to fine detail and used presentation raster setting, but never could get ours to go back to printing as smooth circle again.

Our tubes were 2" diameter and 12" radius. Actually, they are more like curved rods because they were not modeled as hollow like a tube.

[Dimitri Harvalias]

Sorry, I stand corrected.:Oops:
I guess I've never had the need to model a curvy bit that small that I would blow up to the point of being able to notice the issue.

[knurrebusk]

This makes me wonder if segmentation of imported Polylines shod be a choose in DXF/DWG import.

Cant remember the segmentation command in Autocad, but it exists.

Terrain will be much smoother.

Sorry for my bad spelling! but this is very important for me!
If I can improve segmentation into Revit from DXF/DWG life would ease very much!

[Gadget Man]

... curved objects of a small size might appear to be insufficiently tessellated (...) The decision to impose this limitation was made in the early days of Revit Technology Corporation and it allowed significant development simplification.
I can see where you are comming from, and now I understand why they look so weird, but I wish it was limited to a little smaller elements, than door knobs, vanity taps, cupboard handles, etc... They don't look very elegant in larger scale details, but it is not that important (;)). It would be nicer if they were, but...oh well, such is life...

[knurrebusk]

Yes!

Details that most of the nice people on this boad shy away from.

Sorry for my bad language.

[Alex Page]

Not good - look at this handrail section.....nothing we can do?

[Alex Page]

And this one - which is a filled region (opaque) over the top of the model

[comhasse]

I recently started detailing facades and special structures in Revit at 1:1 scale. Lots of pipes and curves, some of it almost mechanical engineering. The segmentation of curves is a real problem. It really defeats the purpose if I have to redraw everything in 2d that I've previously modeled in 3d.

What's worse, even the filled regions have that problem. A circular edge of a filled region is actually displayed as a 24-sided regular polygon. A 300mm diameter steel pipe in section at scale 1:1 looks simply unacceptable. The only workaround is drawing the filled region with invisible edges and slightly, then draw the edges separately as detail lines. Still does not look good because the hatch lines overlap the contour in some places and do not reach it in others.

I can understand the tessellation problem of 3d objects, but the problem with filled regions does just not make any sense - it needs to be fixed. Or has it been fixed in 2010 perhaps?