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# [Box2D]Problem with joints - simple moving

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Hi, Im writting because i have problem with using joints in Box2D. Im trying to create simple moving system for my units but i cannot find out how to move units with this and this speed. I was trying to use linear Velocity but i have to control when units are on place in which i want them. Ive tried joints but they are working like a... gum? U know, at start they move slow but if they are closer to target position my unit moves faster.
Can u give me an advice how to use joints to have an effect like i want? (i was looking for good tutorial about this but all are with jumping boxes, moving them with mouse or car with wheels:( )

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Try to search for "kinematic" bodies. The documentation advises to move the by setting their velocity, but that's not very hard to adapt to follow a position path.

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But when i setting their velocity ill have to control when to stop them because this is force vector, so when they reach my target they will still keep moving.

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It is not a "force vector", just the velocity. But like a manual force, you have to recalculate the value at each step. So for example when the target is reached, you just set the velocity to 0.

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thank you i ll try to use it.

Edit:
kinematics are bad idea because i need colisions, sometimes joints etc.
And still i dont know WHEN to stop moving object.
If i do sth like this:
 Vector_2D range=pos - target; range=range*range; if(range.x+range.y < 10) stop(); 
my body can still keep moving if it colide with something in its way.

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