[F8] Render pipeline

Hi,

I'm researching BitmapData() and MovieClip.cacheAsBitmap() for future use in the render pipeline of my game engine, but sofar I have yet to find any information regarding compositing and palette swapping. I should dig deeper on my own, but I'll be lazy and ask those of you that have already waded through the material.

Issue 1: Compositing

What I need to be able to do is copy the pixels of a *.gif in a MovieClip and paste it on to an empty (transparent) BitmapData object. The best example I can give is copying the final "at rest" position of snowflakes to an overlay of a map's terrain. The snowflakes are a cumulative effect that gets added into the BitmapData object before being individually removed from the stage.

The same concept of cumulative effects will be heavily needed for other aspects of my engine. In fact, the character creation system itself would fail utterly (in concept) if it was not possible to combine bitmaps and store the result for later use.

I feel I should clarify. I want to use frame sheets for my animation, whereby all frames for a given element are condensed on to a single bitmap and the overall bitmap is translated beneath a mask to simulate successive frames. It is this that I want to copy, not a static image whose MovieClip is orientated or a successive timeline frame.

Issue 2: Palette Swapping

Alot of low-level animation in the olden days of yore was done by using grayscale images whose values were replaced by cycling colors. Lufia 2 has waterfalls that are essentially nothing more than a single frame whose values are "strobed" from dark to light blue in a loop, giving the illusion of fluid animation. Is color substitution very efficient in Flash 8, or is it best used only rarely?

More succinctly, can such manipulations be animated or are they sluggish?

Thanks for your patience.