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Hi everybody,

i'm trying to calculate the acceleration of the user car in real time. I already tried the approach documented in this thread, which says to calculate the acceleration in the updateAction using velocity_delta / dt.

using body->getDeltaLinearVelocity() for the delta_velocity returns me always vector(0,0,0). Does anyone have an hint how to get delta_velocity or any other hint how to calculate the acceleration of a car in real time?

thank you in advance!

(09-25-2012, 09:01 AM)kidice Wrote: [ -> ]Hi everybody,

i'm trying to calculate the acceleration of the user car in real time. I already tried the approach documented in this thread, which says to calculate the acceleration in the updateAction using velocity_delta / dt.

using body->getDeltaLinearVelocity() for the delta_velocity returns me always vector(0,0,0). Does anyone have an hint how to get delta_velocity or any other hint how to calculate the acceleration of a car in real time?

thank you in advance!

getDeltaLinearVelocity() is a bullet internal method used in the constraint solver. You have to calculate the acceleration yourself from current and previous velocity.
new_velocity = body->getLinearVelocity();
acceleration = (new_velocity - old_velocity) / dt;
old_velocity = new_velocity;

(09-25-2012, 02:53 PM)NaN Wrote: [ -> ]getDeltaLinearVelocity() is a bullet internal method used in the constraint solver. You have to calculate the acceleration yourself from current and previous velocity.
new_velocity = body->getLinearVelocity();
acceleration = (new_velocity - old_velocity) / dt;
old_velocity = new_velocity;

hi nan!
thank you! that piece of code worked for me. I think, I have to get more familiar with bullet