Re: Point Cloud to NURBS...

From: Rod McCormick (rmccormick@netcarrier.com)
Date: Tue Apr 03 2001 - 18:31:10 EEST


Doug,

There was talk of formZ adding that capability--I don't know if it has been
added or if it is still under development. I did a quick search of the site
and found info on how to do it by hand--tedious, but avoids expensive
software if you have more time than money. In any case, even with the
specialized software you might have to do a lot of manipulation of the point
cloud to get a surface suitable for your purposes. Rhino might be able to
handle the date in a similar way to formZ. I've pasted in part of the
archive discusssion, you can find it complete at:
 
http://www.formz.com/web_site_2000/content_pages/forum/forum_archive/forumD/
general/365.html

Good luck.

Rod

-- 
Rod McCormick
Professor of Jewelry & Metalsmithing
University of the Arts
320 S. Broad Street
Philadelphia, PA 19102
(215) 717-6600
rmccormick@uarts.edu

Summary: Point cloud meshes

Chris,

Currently there is not a way to automatically generate a mesh from point cloud information. There are programs that will do that sort of thing, however, they are fairly pricey. If you were to use the point cloud information inside form€Z, you would manually interpret the points by using the points as a template or using them as points of reference for snapping.

ZwebTechSupport ------------------------------------------------------------------------ Bo Atkinson Mon, September 06, 1999 at 05:29 PM

Summary: fZ - ACIS import /export

I highly recommend using formZ ACIS import / export options to get ideal, (equal sized, triangulated meshes) from formZ, after you do bother to click sufficiently through the point cloud as a template. (Search Z archives for more details). Actually this might be an advantage because the "feel" you might seek in 3d may not conform with popular 3d math conventions which are readily available. Ok, i speak as an artist, but "feel" goes well beyond math. in the production markets, if you can handle this point.

Fact is it takes not too many clicks in fZ to close surfaces in fZ and then generate meshes. You can start with 3d meshes, fZ tolerates this sort of 3d snapping, and you don't necessarily have to formalize the triangulation at first.

This is a very great strength in Z. You can build real 3d in abreviated forms. Then, if it be worthwhile, you can go ahead and triangulate according to the cultural feel you intend in the geometry. As hinted above, my preference lies with the ACIS import/export route for automated triangulation- reconfiguration. The easier forms of triangulation in the regular tools of Z produce less eqilateral triangles. So i mention the less known route, which seems more like a work around within Z, but, rather, is very handy.

The deeper point i make here is that the initial outlines one can make fom from a point cloud do go a long way to "idealizing" the final product. Are ytou interested in the best or "good enough"? That is the question. Your post did not express the the end product.

on 4/1/01 4:13 AM, Douglas J. Bucci at BUCCI@prodigy.net wrote:

Hello- I am in need of a way to convert point cloud data into NURBS surfaces. I am working with a Vivid700 Minolta scanner and need a way to bring the point cloud data into Rhinoceros & manipulate it. Your help is greatly appreciated. Thank you in advance, Doug Buci www.dbucci.com <http://www.dbucci.com>

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