how calculate reach top position from addforce and gravity ??

Im making platformer games, and I want to change animation when my character jumps and reach top position

Im jumping using script like this

Code (CSharp):

1. if(Input.GetButtonDown("Jump") && grounded)
2.             rigidbody2D.AddForce(new Vector2(0f, 300));

and Im using rigidbody2d, with gravityscale = 1 and mass = 1, physics2D setting for gravity (0, -9.81)
anyone knows how to calculate when I reach top position ??
Im thinking using rigidbody2D.velocity, cos I see the value when up until 5.8 and when fall the value when < 0
but how I know the max value is 5.8 ??

anyone can help ??

 

You can add a trigger variable in your animator controller that changes to a different animation when your y-velocity becomes negative, and reset it when you either become grounded again or grab onto something.

I hope you're not confusing velocity with height when you talk about the value of 5.8.

William