I'm not sure I totally get the question because i've been deprived of sleep lately! (talking to countries with very little time overlap at each end of a normal day gah, for the love of my blankie let me sleep!)
However you are aware that the colour index is four bytes, with the fourth being alpha?
I have done non-alpha blends before and I tend to break the pixel down into individual colour components as I find this makes it easier.
blendLevel= value between 0 .. 1
red=( sourceRed*blendLevel ) + ( destinationRed* (1-blendLevel) )
However you are aware that the colour index is four bytes, with the fourth being alpha?
I have done non-alpha blends before and I tend to break the pixel down into individual colour components as I find this makes it easier.
blendLevel= value between 0 .. 1
red=( sourceRed*blendLevel ) + ( destinationRed* (1-blendLevel) )