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@shehab10 wrote:
Hello, i need a lisp that construct line between two lines of wall by selection called (Wall Centerline)
i attach example of what i want assuming that i will often isolate wall layer in the project to facilitate the task.
Are they Wall objects as in Architectural overlay programs? If so, this might not work, and regardless, you would probably be better off building the centerlines into the definitions of the Wall objects if you can. But if they're Lines or Polylines [or the same within Blocks, or just about any other straight entity], try the Bisector.lsp routine, with its BI command, here. In the case of selection of two parallel straight objects, it draws an Xline halfway between them, i.e. bisecting the distance between them. [If they're not parallel, it draws one bisecting the angle between them.] You would still need to Trim and/or Fillet the resulting Xlines.
Kent Cooper, AIA 
I don't use Revit but did you Google it should be possible to take a DWG line and make it a wall. The issue is that you will probably have to add the doors and windows again. As in a trace over scenario.
As a side note a method is to pick lines in sequence for each side 1 line only and offset a new cl and fillet etc as you go. So even though doors and windows a line would appear copyrighted solution.
I have a CAD dwg that contains the floor plan of the building including wall lines. I am currently working on a Revit add-in to automate the process of generating the walls in Revit from 2D CAD drawing and finding the centerlines is vital because in order to create walls programmatically in Revit, the centerline of the walls is one of the input parameters.
My workflow consists of importing the CAD drawings into Revit and then running the Revit add-in. If the imported CAD drawings has the centerlines of the wall already, I can retrieve those centerlines and model the walls appropriately. Thus, if a LISP exists that can create wall centerline in the DWG file before importing to Revit (which is basically just as demanded by the thread starter), it would be great.
For sample, I have attached a simple floor plan drawing for testing.
In general, what I need to have is more or less the same as the starter of this thread. From the wall lines, I need to create the centerlines (colored red below):
Sorry if I sounded too demanding. I am open to different approach that will lead to a proper solution. Thank you
You can 2 point drag over 2 lines so get all sorts of info start/end angle etc so I think it would be a bit like the MLINE options as sequences of building the centre line.
Something like, do drag start over 2 lines, pick end/style I can see the most common would be start goes to end, "T", "+" etc, will have a think.
Kent may have done work on his prior offering.
I tested it and it works in the way that it can create single centerlines like this:
Thank you for your help and efforts in making this. Thought this would be enough for now, I am looking for something that could be faster (for example like by selecting all of the walls and then create the centerlines at the same time).
@kevin.anggrek wrote:
.... I am looking for something that could be faster (for example like by selecting all of the walls and then create the centerlines at the same time).
I have a routine called BISECTOR.lsp with its BI command, available >here<. It will do that kind of mid-line between any two straight things, whether Lines, Polyline line segments, such things inside Blocks, etc. But it makes XLINEs, [which you would Fillet/Trim, but which also means multiple collinear wall segments can have their mid-lines drawn collectively from only one of the portions], and it does require picking individually on the two things.
However, to do what you're asking would be a hugely complicated challenge, if even possible. It would require comparing every Line in the drawing to every other Line, deciding whether they're parallel and within some limit of distance apart [so it won't draw Lines through the center of rooms] and within some range of proximity to each other, and determining somehow whether the mid-line between them had already been drawn based on some Lines already considered, one of which might be the same as one of those currently under consideration. Since not all the walls are the same thickness [though most are], there needs to be some range of allowable distance between parallel Lines, which would probably mean it would draw Lines down the middle of the width of all the steps, and literally thousands of Lines all over the apparent exploded Hatch pattern in the Car Parking area.
Just an example of some of the complications [I changed some colors for illustration]:
To get a routine to realize that the mid-line between the red Lines and the one between the yellow Lines should be one resulting Line would be an enormously complex task. And if it compares the yellow Lines before it gets to considering the green one [which we can't assume], the upper-yellow-to-green comparison involves something that's already been dealt with along with something that has not. And that green Line's short length is likely to be within the range of possible wall thickness, so would it be removed from consideration, because it's likely to be an end-of-wall Line like the magenta ones?
Another:
If you use @Sea-Haven's routine on the cyan and orange Lines, depending on the order in which you pick the ends of the fence, it can Offset either one, with different-length results. If it does the cyan one, that covers the wall section between cyan and blue, so the blue Line should presumably be removed from consideration by an automating routine, but how can it do that when it's looking at the orange and cyan ones? If it Offsets the orange one, when it gets to comparing cyan to blue, it might then Offset the cyan one, so there will be two partially-overlapping results.
I don't mean to sound discouraging, but to come up with something that would begin to do what you want would take more time than doing a very large number of these manually with a routine such as those already suggested to help, and some Fillet/Extend/Trim operations.
[By the way, the one Layer name suggests this plan comes from some on-line source of sample drawings. I think you need to find a better source. Everything is on the same Layer -- differentiating wall Lines from others would be a big start on making the work of a routine at least easier, if the other complications can be overcome. There are duplicated Lines overlaying each other. Many things about it are utterly unrealistic -- the exterior wall Lines run right across the window openings, the upper-middle bathrooms have only a single Line between them and the stair with no wall thickness, the stair has no openings into it (!) on either floor, the exterior walls are the same thickness as most of the interior partitions, etc., etc.]
Kent Cooper, AIA
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