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[Nadia Alramli <nadiana@xxxxxxxxx>]

Public bug reported:

when calculating the opacity, in the reflection and background actions (and possible others) we are using this method:
opacity = int(2.55 * opacity)
if opacity is 100 the result is:
int(2.55 * 100)= int(249.99999999999999) = 244

Which is generating inaccurate results. The correct way of calculating is:
opacity = (255 * opacity) / 100

** Affects: phatch
     Importance: Critical
     Assignee: Nadia Alramli (nadiana)
         Status: New

** Changed in: phatch
   Importance: Undecided => Critical

** Changed in: phatch
     Assignee: (unassigned) => Nadia Alramli (nadiana)

-- 
Inaccurate opacity floating point calculations
https://bugs.launchpad.net/bugs/384420
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Status in Phatch = Photo & Batch!: New

Bug description:
when calculating the opacity, in the reflection and background actions (and possible others) we are using this method:
opacity = int(2.55 * opacity)
if opacity is 100 the result is:
int(2.55 * 100)= int(249.99999999999999) = 244

Which is generating inaccurate results. The correct way of calculating is:
opacity = (255 * opacity) / 100