Why not take the average of alpha in all cases? Eliot (phone)
On Mar 21, 2015, at 6:32 AM, Aliaksei Syrel <alex.sy...@gmail.com> wrote: > > On Sat, Mar 21, 2015 at 3:41 AM, Ben Coman <b...@openinworld.com> wrote: >> Do we need to do something for Pharo 4? And what is the simplest/quickest >> thing that would work - even if it needs revisiting in Pharo 5? > > > The most simple that works is to at least set alpha to any value. > Multiplication - alpha doesn't change > Division - alpha doesn't change > Addition - (color1 apha + color2 alpha) min: 1.0 - simple addition and check > to not allow alpha to overcome max value > Subtraction - if two colors are the same alpha becomes 0, otherwise we take > alpha of message receiver (minuend) > Slice is in inbox (15188) > > Cheers, > Alex
