mmmm There would be many ways to do this..
Taking into consideration that you are using Physics and would have less physical control than any other way...
I cant see any single solution would be adequate..However, I would experiment with several and find which ones works best for your game...or combination of the best..
Some options I would experiment with include
1:- an Invisible helper sprite that assisted in controlling the ball...You could make it any shape you like (concave shape??) and set its angle to the angle/direction of motion of the player.. To always "scoop" the ball to a point of course..because there would always be moments when you "lose the Ball"..this could even be something as simple as two bars of intersected guides that saddle either side of the ball...
2:-You could always try to call a set position event first for the ball...or move at angle to position near your players foot and update it as necessary every tick if need be...The screen update would be so fast that it should appear instantaneous...if you need to vary the amount of "Stick" use a variable that is linked to a floating integer of the players speed of motion, angle, whether he is being tackled etc...as this variable increases or decreases you would have more or less control over where the ball is...up until the point that you have no control or FULL control...
3:- use some sort other system that is NOT these...lol.. cant think of any more right now..I would use a mix of the two...Physical objects that "Help" and a system of floating variables that help "fix" it to the player via the width of the helper sprites.. based on certain game relevant factors..
eg: Player speed decreases control of ball
& Player skill level increases control of ball
& Player is tackled by opposing side and match is in Great Britain..= Riot and Hooligan increase by 64%..
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