Reduce cpu usage with bitmapdata?

hello dear kirupa folk

i often need to do alpha / colormatrix transitions on very large, complex movieclips. this has proved to be very heavy on CPU.

i want to create a bitmap photo of an mc, hide the mc, do the transition on the bitmap, change the mc in the background to the target state, and when the transition ended, delete the bitmap and reveal the mc.

i have tried to do this with bitmapdata, but after some time i figured it will take me a couple of days to figure out a clean and efficient way, and i am trying to save myself time. (i hope you dont blame me fot this).

has anyone heard of / can make up in a sec - a class to do this automatically?

very much thanks,