Scratch

Well why need to go to that link? (No offense) But there is a faster way. Just go to the Scratch program open Scratch, click file, click open, click examples, click Pong, take a look at their scripts and *drum roll* you have it!

If you want gravity to be applied to the ball, tell it to decelerate 9.8m/s, which is approximately the effect of gravity, you can unify each step to be a meter, making it 9.8 steps a second, then divide that by around 30 to make it slow by about 0.327 steps a frame (I might be wrong, I'm just assuming that scratch runs at 30fps).

<forever>
<change{ y velocity }by( -0.327 )
<if on edge, bounce>

^That I think would mimic the constant pull of gravity.
Use the variable Y velocity, or another variable with a different name to tell how many steps the sprite will move, and use <change y by( <{ y velocity }> for the motion of the sprite you're going to make move, it'll move on the up/down or y axis at the speed that will be effected by gravity.

For hitting the ground try

<if><touching[ ground ]>
<point in direction( (( 180 <-> <direction> ))

and for a wall, try

<if><touching[ wall ]>
<point in direction( (( 0 <-> <direction> ))

I hope this helps!

Last edited by Flait7 (2011-07-18 23:08:37)