PDA

View Full Version : AutoCAD Polylines to Revit Room Separators



yongkukim
2009-04-30, 11:03 PM
If I have AutoCAD drawings with closed polylines for all the rooms, what is the quickest way to bring this file into Revit and have the more intelligent Revit Rooms for each polyline? It appears I need to re-trace all the polylines as Room Separators in Revit if I just want a quick Revit version of the building with just the Spaces.

Steve_Stafford
2009-05-01, 01:28 AM
Something must be lost in translation? I don't understand what you hope to gain by having a room separation line model? Not trying to be snarky. Revit assumes you'll use walls to define rooms and occasionally some room separation lines to define "rooms" that are not bounded by real walls.

There isn't a way, unless you are a programmer, to do what you describe...that comes to mind. How many rooms are we talking about? Is it a single line layout or does it allow for the width of walls between the rooms? If there are spaces between rooms for walls then you ought to sketch walls instead...use the Pick option to pick the cad lines, might be quicker than sketching point by point.

yongkukim
2009-05-01, 03:19 AM
Thanks for reply and snarky is fine :)
I am thinking in general for scenarios where someone might have a lot of past AutoCAD dwgs and are interested in developing a phased strategy for creating Revit models out of them. My issue was trying to understand how much "intelligence" from the AutoCAD files can be brought over to Revit in the first pass with minimal modeling.

For example let's say you have four DWG files, each representing a floor of a building. It would be great to import these multiple files into one Revit file - each on the correct corresponding Level (1st flr, 2nd flr, 3rd flr, 4th flr). From there it would be nice to use even just the Revit Schedule tool in this "room only" model. The intent is this would be only the start of eventually creating the more detailed Revit model (walls, doors, windows, etc) but I just wanted to see how much intelligence I could get from the initial, minimal effort.
Thanks

azmz3
2009-05-01, 02:08 PM
Like Steve said, there isnt really a possible way for this. But in your second example, lets say you have fours DWG files, you can bring them all into Revit in one file, put each drawings on its correct level. if you just want to get basic shapes and rooms, you could use massing for that. you can create a mass for the entire building envelope, and create masses for the floors/ceiling/walls, that would give you the rooms within each floor. This would probably be the quickest way.

When you bring a DWG into Revit, there is no intelligence from CAD, Revit wont recognize the polylines from CAD, and since the DWG is a link anyway, it merely acts as a background. Think of a CAD import as a "dumb block"

SamuelAB
2011-11-17, 06:11 PM
I would hide everything except the CAD drawing on each floor. Turn off all the layers except the room boundaries in of the CAD drawing in Revit and do a pick line with TAB. TAB will allow you to select lines that are touching each other, so you will save a lot of time.

However, like the comments above say, you are better off using walls with SOME room separation lines.

MikeJarosz
2011-11-17, 07:13 PM
I am one of those "programmers" who has battled Acad polylines. Acad polylines were implemented using a strange, hybrid geometry. X and Y use cartesian coordinates, but z does not. The z coordinate of a polyline is in fact a vector. Working with it requires an understanding of vector math and matrix arithmetic such as dot products and cross products. And that's before you even get into the Revit API.

It is definitely not for the fainthearted. I remember writing VBA scripts for dot product and cross product, because none of the programming languages provide those functions they way they do square roots and trig.

Nevertheless, post your request on the right forum and you might find the special someone who can do it. Everything I learned about Acad polylines I got from some guy in New Zealand who just happened to know linear algebra inside out!