Nathan Kopp <nat### [at] koppcom> wrote:
> There's a fundamental difference between vnormalize(<0,0,0>) and 1/0:
> backwards compatibility.  :-)

  I don't think vnormalize has ever been defined as returning <0,0,0> if
a zero-vector is given to it. What has not been defined can change in the
future without breaking backwards compatibility.
  Besides, backwards compatibility has never been such a strong issue in
POV-Ray to maintain bad behaviour or bad features. For example, filter
working as transmit in layered textures was a bad behaviour and it was
fixed regardless of breaking backwards compatibility.

  IMO trying to perform vnormalize(<0,0,0>) is a sign of a programming
mistake (ie. bug) and thus the error is only helpful. If the algorithm
is properly made, such case should never happen (in the exact same way as
dividing by 0 should never happen).

-- 
#macro N(D)#if(D>99)cylinder{M()#local D=div(D,104);M().5,2pigment{rgb M()}}
N(D)#end#end#macro M()<mod(D,13)-6mod(div(D,13)8)-3,10>#end blob{
N(11117333955)N(4254934330)N(3900569407)N(7382340)N(3358)N(970)}//  - Warp -

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