Trampoline effect (low jump to high jump)

Questions & Answers
1

Hi,
I want my player to start jumping close to the trampoline then gradually making it jump higher and higher.

Is this the right way to implement that effect or am I doing something wrong ?

void OnCollisionStay2D(Collision2D col)
{
   for (jumpForce = 10; jumpForce < 100 ; jumpForce++)
   {
      if(col.gameObject.tag == "Ragdoll")
      {
        rigidbody2D.velocity = new Vector2 (0, jumpForce);
      }
   }
}
2

The trampoline effect is just that the more force there is on the object, the more force the trampoline will apply back.

You can consider at rest the trampoline gives:

force *= 0.8f

so that your guy slowly stops.

Now you can have an acceleration stage where the trampoline gives:

force *= 1.2f

Finally, if not resting nor accelareting then you just use force as 1.

The force is used to send the guy back up:

rigidbody2D.AddForce(transform.up * force);

Your guy will naturally go higher and higher, so you may want to clamp the force so that it gets to a max height (you can define that value based on mass, height of player, skills).

The rest is just visual effect where you stretch the trampoline up and down.