To LUGNET HomepageTo LUGNET News HomepageTo LUGNET Guide Homepage
 Help on Searching
 
Post new message to lugnet.cadOpen lugnet.cad in your NNTP NewsreaderTo LUGNET News Traffic PageSign In (Members)
 CAD / 10865
10864  |  10866
Subject: 
Re: Question: polygons filling a t-shape
Newsgroups: 
lugnet.cad
Date: 
Thu, 4 Dec 2003 03:16:06 GMT
Viewed: 
385 times
  
In lugnet.cad, Niels Karsdorp wrote:
   Hi,

I read somewhere (forgot where) that quads and triangles should not pass by vertices, because this may cause gaps in some renderers.

I suspect they will create artifacts in just about any renderer, but the severity will vary from one to another.


   For L-shapes, the poligons should be created as on the right image:



But how should T-shapes (and H-shapes, too) be created?



(The black lines are edges, the red lines are seperators between polygons)

The above looks fine. You could do it with one less LDraw primitive while still preventing artifacts if you did it like so instead:



Note that all three shapes in the above diagram would be quads, with the fourth point for quad number 2 being at the point the arrow points to. My program LDView currently incorrectly removes that extra point, but I’ve already updated the code to stop doing that, and the next release will act correctly.

--Travis Cobbs



Message has 1 Reply:
  Re: Question: polygons filling a t-shape
 
(...) Great diagrams, thanks! But I thought that (rgarding quad 2 in the last diagram) collinear points were considered an error by the checkers, so that when you submit your part to parts tracker it would be flagged??? (21 years ago, 4-Dec-03, to lugnet.cad, FTX)

Message is in Reply To:
  Question: polygons filling a t-shape
 
Hi, I read somewhere (forgot where) that quads and triangles should not pass by vertices, because this may cause gaps in some renderers. For L-shapes, the poligons should be created as on the right image: (URL) But how should T-shapes (and H-shapes, (...) (21 years ago, 3-Dec-03, to lugnet.cad, FTX)

7 Messages in This Thread:


Entire Thread on One Page:
Nested:  All | Brief | Compact | Dots
Linear:  All | Brief | Compact

This Message and its Replies on One Page:
Nested:  All | Brief | Compact | Dots
Linear:  All | Brief | Compact
    

Custom Search

©2005 LUGNET. All rights reserved. - hosted by steinbruch.info GbR