Ok, so the formula in physics for determining the velocity of an object that has a force that causes constant acceleration is v(t)=Vi+a*t.
first thing you will want to do is determine what your scale for time will be. Refreshes or actual time.
It will probably be refreshes.(this is much easier)
If it is refreshes then forget t, and let vi be the previous v(t)(from the last sync).
So you should have this command in EVERY refresh
Vy=Vy+g;
g is the gravity strength you want. You figure that out.
Then, after other forces ajust the Vy, you should have a command like this:
dbSprite(i,dbSpriteX(i),dbSpriteY(i)+Vy,dbSpriteImage(i));
Here you should check your collisions.
If there is a collision then you know to only affect your y position and velocity. Just remember to change Vy to 0 when the object hits the ground otherwise the game will work until the speed become so great that it teleports off the screen.
I'll get a new signature someday.
