Thanks a lot for your great help.
And I still have a question, how about the PS processing the continuous walking animation. I mean for the continuous walking, I think it can be devided 3 types, one is start walking, second is walking, the thrid is stop walking. If player just press one movement button, it is simple to display these 3 type animation by order, but when the user press the up-arrow button down for a while, then the player should continuously walk in the screen, so for middle of every step, the stop walking animation should not be displayed, and it only be displayed at the end of continuous walking, Right? How about PS processing this problem?
Any suggestion and help will be welcome!
Frank