[Octave-bug-tracker] [bug #45456] hsv2rgb is very strict about its input values

[Carnë Draug]

Follow-up Comment #8, bug #45456 (project octave):

Apparently, Matlab hsv2rgb in 2010b was quite buggy and the behaviour has
changed on recent versions. On Matlab 2013, Matlab returns NaN for invalid RGB
colors:


carandraug:   would you mind also tell me what "hsv2rgb ([2.9 1 .5])"
returns?
carandraug:   and "hsv2rgb ([2.9 1.5 .5])"
xyzwhatever:  NaN   NaN   NaN
carandraug:   for the two examples?
xyzwhatever:  yeah both


However, I kinda disagree with part of input check. The hue in hsv (first
column) is an angle on a cylinder.  Therefore we can simply do:


  ## The value of hue is an angle therefore 0 = 1 = 0° = 360°.
  ## Fix for values outside the [0 1] range which mess up the maths.
  hsv(:,1) = mod (hsv(:,1), 1);


which means that "hsv2rgb ([2.9 1 .5])", which Matlab returns NaNs, could be
computed like "hsv2rgb ([0.9 1 .5])" and would still be correct.

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