Chipp's alphatest revisited

[Wouter]

Hi,

May be this can be a starter for a possible workaround (until the set 
alphaData bug gets solved).
Compute a maskdata from the alphaData of the GoodAlpha image.
It is not perfect because it does not retain the cast shadow set by the 
alphadata.
But the cast shadow can be simulated in other ways if it is only to be 
used on OS X

Set the script of the "set alphadata ->" button to:

on mouseUp
   put binaryEncode("C",0) into transparentPixel
   ### fiddle with this value
   put binaryEncode("C",100) into opaquePixel
   put the imagedata of img "prep" into iData
   put the alphaData of img "prep2" into aData
   repeat for each char i in aData
    if i > opaquePixel then
       put opaquePixel after mData
     else
       put  transparentPixel after mData
     end if
   end repeat
   set the imagedata of img "prep" to iData
   set the maskdata of img "prep" to mData
end mouseUp

(be sure to do the 1 pixel trick or the export to png to retain the 
image)

Greetings,
WA