POV-Ray : Newsgroups : povray.unofficial.patches : Bug in crackle metric 1 Server Time
2 Nov 2024 03:15:23 EDT (-0400)
  Bug in crackle metric 1 (Message 1 to 1 of 1)  
From: Ron Parker
Subject: Bug in crackle metric 1
Date: 11 Feb 2000 10:51:19
Message: <slrn8a8blp.v8.ron.parker@ron.gwmicro.com>
I was playing around with crackle metric 1 for SamuelT's maze enigma over
in p.b.i. and I found a bug (thanks to Thomas Willhalm for pointing me at 
it, even though he might not realize he did.)  When it computes the taxicab 
metric (metric 1) it doesn't take the absolute values of the distances 
before adding them together, which makes the probability of a nonzero cell 
pretty low in about half of space.  

There is currently code that goes something like this:

  else if ( UseUnity ) {
          minsum2 = dv[X] + dv[Y] + dv[Z];

in at least four places in the code.  The part that says 

dv[X] + dv[Y] + dv[Z]

should instead say 

fabs(dv[X]) + fabs(dv[Y]) + fabs(dv[Z])

Hopefully this can be fixed for the next MegaPOV.

-- 
These are my opinions.  I do NOT speak for the POV-Team.
The superpatch: http://www2.fwi.com/~parkerr/superpatch/
My other stuff: http://www2.fwi.com/~parkerr/traces.html


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