I'm developing a flash game and I hired a graphic designer to make it look more professional. The problem is that I don't know if I should use timelime animations or sprite sheets. Here is an example of his graphics: www.quickguitartuner.com/monster_reduced.png
How should I proceed for better performance?
Also, if I just split the sprite sheets in many images, put them on an array and keep using add/removeChild() on them will it work properly when talking about performance?
According to Lee Brimlow, an Adobe Flash platform spokesperson, blitting in flash gives much better performance than using the display list. He has produced several video tutorials on how to do this starting from scratch, which should answer your question "how should I proceed":
http://gotoandlearn.com/play.php?id=140
http://gotoandlearn.com/play.php?id=141
http://gotoandlearn.com/play.php?id=142
http://www.gotoandlearn.com/play.php?id=143
It's better to let the artist make the animations in the timeline, as vector drawings. Converting to a sprite sheet can be done afterwards, if needed. You could even do some bitmap caching (of the whole animation - instead of the default bitmap caching Flash offers) of yourself at runtime.
If you have a vector/timeline animation you can still scale the object without loss of detail and scale the animation in time without it becoming a set of discrete frame switches. It gives you a lot of freedom afterwards to tweak your game.
So, ask the artist to make vector/timeline animation, you can still convert it to bitmaps/spritesheets later. Also, if the animation is complex (ie there are some discrete movements) you can also ask the artist to stretch out the animation over more frames then you actually need. You can skip a few frames in the animation if you need it to run faster.
