blend function urgently needed in kdelibs

[Matthew Woehlke]

Tobias G. Pfeiffer wrote:
> On Wednesday 23 May 2007, 00:40, Matthew Woehlke wrote:
>> Firstly: I don't even want to /contemplate/ a three-way blend, at least,
>> not further than blend( blend( a, b ), c ). 
> 
> I doubt this would give the same results. If you want a, b and c to be equally 
> represented in the result, this will definitely not do it, as it would 
> probably be doing 0.5*(0.5*a+0.5*b) + 0.5*c = 0.25*a + 0.25*b + 0.5*c

You want blend( blend( a, b ), c, 2.0/3.0 ) :-).

2/3*(0.5*a + 0.5*b) + 1/3*c = 1/3*a + 1/3*b + 1/3*c.

-- 
Matthew
"I can hear you / just barely hear you / I can just barely hear you"
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