Physics Help

I believe Box2D has a 'freeze rotation' option; if so, that might solve your first problem.

hello

i have successfully made a catapult using Box2d...i have a player sitting on the catapult ...the catapult throws the player in the air.
the user playing tries to maintain the player angle through the accelerometer which if he fails the player angle changes due to air resistance and the player rotates in mid air(or stalls)

here is the code i implemented..
1. the code below makes my player move in the air in a parabolic fashion..and after colliding to the ground comes to the halt(for which i applied friction, angluar damping)

- (void) CorrectPlayerRotation
{
b2Vec2 _linearVelocity;
float32 _velocityAngle = 0;

_linearVelocity = gameBodies[BOD_ANIM_PLAYER]->GetLinearVelocity();
_velocityAngle = atan2f(_linearVelocity.y, _linearVelocity.x);

gameBodies[BOD_ANIM_PLAYER]->SetTransform(gameBodies[BOD_ANIM_PLAYER]->GetPosition(), _velocityAngle);
}

i basically want to know as to how do i implement the air resistance thing and also get the player rotating in mid air after he fails to maintain a balanced angle...
P.S: the game and effect is similar to the link http://www.miniclip....es/catapult/en/