code:
<edit>newer code above!</edit>

this is my motor code... i would like to emit dust particles when the wheels slip. how could i find out if a wheel slips? should i compare the moved distance per frame with (wheel_circumference/360)*rotated_degrees and if it doesn't match it means the wheel slips?

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thanks for the answers marco!

what do the spring/damper constants do? this isn't explained in the manual very well...