Mark:
I normally suggest separating the building outlines from the ground-level
data and gridding them using the Region-to-Grid function (not
interpolation). This requires the building outline to have a single
'height' attribute. This is usually the case for data translated to MI
format since MI can't yet handle 3D polylines. For buildings with multiple
'steps' each inset building outline (as you go higher and higher on a single
building) gets stamped into the grid cells of the previous level. The
ground level points can be interpolated separately from the buildings and
the two grids stamped together with the grid splicer.
Most data from our digital photogrammetry system, or outside sources, are 3D
heighted polylines, not isolines of continuous elevation. The data is
usually kept in .DXF format which can handle true 3D linework. We,
internally, have built custom processing tools that work directly with .DXF
files. It allows us to process irregularly heighted buildings and ground
level data into VM grids using a combination of triangulation and linear
interpolation steps.
regards,
Phil
Philip H. Wyatt
V.P. Technology
Northwood Geoscience Ltd.
43 Auriga Dr., Nepean, Ontario, Canada, K2E 7Y8
Phone 1.613.224.2020 ext 340, FAX 1.613.224.2785
Internet: www.northwoodgeo.com
----- Original Message -----
From: mark snow <[EMAIL PROTECTED]>
To: <[EMAIL PROTECTED]>
Sent: Tuesday, April 27, 1999 2:09 AM
Subject: MI VM Building representation
>Any suggestions on the following:-
>
>I've imported .dxf (3-d image) of a collection of buildings (viewable in
>CAD) into mapinfo and vertical mapper - used poly2point to create point
>data but can't fathom which is the best method to interpolate and view
>image. All methods tried so far have distored the original .dxf . What's
>the best way to go about this? I have seen VM used for city
>representation before particularly with radio propogation mapping.
>
>Cheers,
>
>Mark.
>---
>Mark Snow
>Centre for Research in the Built Environment
>Cardiff University, Wales
>Visiting associate at SOLARCH
>Unversity of New South Wales, Australia
>
>
>
>
>
>----------------------------------------------------------------------
>To unsubscribe from this list, send e-mail to [EMAIL PROTECTED] and put
>"unsubscribe MAPINFO-L" in the message body, or contact [EMAIL PROTECTED]
>
>
----------------------------------------------------------------------
To unsubscribe from this list, send e-mail to [EMAIL PROTECTED] and put
"unsubscribe MAPINFO-L" in the message body, or contact [EMAIL PROTECTED]
