Importing 3D AutoCad & Creating Topo

[Davied2]

Hi all

I always have sucess using the fantastic Revit tool of "use imported" to select an imported 3D AutoCad survey to automatically create a 3d Topo Surface in Revit.

This morning I have been given a 3D AutoCad survey where all the levels have been put in as AutoCad points. Each point has a Z value.

The DWG imports fine, however, when I come to create my 3D Topo Surface using the "use imported" function it totally ignores the Autocad points.

Has anyone else had this or knows a work around to save me going into AutoCad and replacing all the points with either a cross or block so that the Topo creates in Revit.

Regards

Dave

[Max Lloyd]

Davied,

Points aren't recognised unfortunately. Doesn't matter what node point symbol you assign to them in AutoCAD.

Check out this (http://forums.augi.com/showthread.php?t=26232&highlight=site+topography) thread where I had the same problem. The solution is to place a small line or circle on each of the points first in AutoCAD. A bit laborious, but miles quicker than typing in all the levels in Revit.

Max.

[Davied2]

Thanks Max

At least its good to know for the future that it cannot be done with points.

Thanks for reply and suggestions from the thread

Dave

[Lashers]

Davied,
Find a friendly surveyor (or go back to whomever supplied the points?) they should have a program that interpolates the points to contour lines if they do land surveys. That should do the job.

[Melarch]

Or have the land surveyor give you a copy of the text file that has all of the points listed. Autodesk Revit Building 8.1 can interpolate these points directly from the file into a 3D Revit topo surface.

[Dimitri Harvalias]

Or use the fabuluous SEARCH tool on the AUGI Forum to find a simple LISP routine that does it all for you. (thanks to the talented Mr. James Vandezande :beer: )


http://forums.augi.com/showthread.php?t=3471&page=2&pp=10&highlight=survey+point+lisp

[gordolake]

Hi all, here is a lisp routine for autocad that will replace points selected with circles to fix this oversite in revit.

The radius is set in the lisp file (see comments therein), you will need to change it to an appropriate size depending on what units the survey drawing is, (currently set at 150 for millimeter dwg). A new layer is created to place these circles on (RVT-TOPO) so its easy to select this with the import option in revit.

It will select all points in the drawing so you may need to edit out non surface points ie you wont want pit inverts or building floors etc. so you extract the points needed to a separate dwg.

copy and paste below to gentopo.lsp and load in autocad and run with command "gentopo" this is a basic lisp file and doesn't have much error handling.

(defun c:gentopo (/ ss1 blkcount current ed blkspace blkinsert)
;; make new layer for topography
(command "-layer" "m" "RVT-TOPO" "c" "3" "" "")
;; select all points
(setq ss1 (ssget "x" '((0 . "POINT"))))

(setq blkcount (sslength ss1))
(setq current 0)
(while (< current blkcount)
(setq ed (ssname ss1 current))
(setq ed (entget ed))
(setq blkspace (cdr (assoc 410 ed)))
(setq blkinsert (cdr (assoc 10 ed)))

(setvar "ctab" blkspace)
;;;
;;; DRAW THE CIRCLE - LAST VALUE IS RADIUS
;;;
(command "_.circle" blkinsert "150")
(setq current (+ current 1))
)
(princ)

)
Hope this helps and I think revit needs fixing to allow point entities to be used from a surveyors dwg as this is a basic drawing object used by most surveyors software.

I also have lisp for short line midpoint to point and 0 length line to point because some software generates short crossed lines for points or 0 lenght lines as a dot.

Steve

[Davied2]

Steve

Thanks for posting that LISP file - it will come in handy until the oversite is fixed in Revit.

Regards

Dave

[gbrowne]

Thanks for this thread, it just saved the day! This is still something that needs attention.