Parabolic movement of a ball in Box2d

SimplesApps

Just wondering if there were a way to achieve a parabolic movement of a ball (in a box2d world).

Something like @ar2rsawseen slingshot's but with parabolic movement:
http://appcodingeasy.com/Gideros-Mobile/Gideros--Box2d-Slingshot

Thanks in advance.

talis

Correct me if i am mistaken but a slingshot can already generate a parabolic movement in box2d physics.
In @ar2rsawseen 's example just the world is limited with walls so you can not see the parabolic movement with those parameters.
In order to see it just decrease the strength parameter(it is by default 1.0 in the example make it 0.4 or 0.5 you will see) a little bit and slingshot the ball up with some angle. You will notice that a parabolic movement is automatically generated hence you are applying both x and y vector forces to the ball object.
Because there is gravity also set in box2d, automatically a parabolic movement will be generated when the speed of the ball decrease. (You can also increase the friction a little bit)

SimplesApps

Thanks @talis.

Yes, I was playing with the strength value and also I have to take into account the ball density, friction and restitution parameters. Another option is to set a higher value for the gravity. But it's not easy for me to achieve the best parabolic movement.

Btw, do you know any way to draw the trajectory with a curve or broken line?

Thanks.

talis

@SimplesApps you are welcome.

For the trajectory curve, look to this http://giderosmobile.com/forum/discussion/2826/show-path-of-physics/p1

It is not lua but box2d. So just needs to be converted thats it.

SimplesApps

Thanks again @talis , the example helped me a lot.

I've converted to lua and it's working almost the majority of the times.
I guess it's hard to get it to work perfect.