relative acceleration

[CptBBQ 10]

Hi everyone,

I´ve ran into a problem I just can´t explain to myself. I´ve taken this code from the biki:

_vel = velocity _vehicle;

_dir = direction _vehicle;

_speed = 80;

_vehicle setVelocity [(sin _dir*_speed),(cos _dir*_speed),(_vel select 2)];

It should accelerate a vehicle in the direction it´s already heading towards.

I just changed it a little so _speed isn´t added to the velocity but velocity is set to _speed.

I need to use this script on two different vehicles:

Old_moto_TK_Civ_EP1 and S1203_TK_CIV_EP1

With the motorcycle everything works as intended but the car just makes a small leap, and then it stops abruptly.

I´m completely baffled about this because the only difference in the code is the vehicle classname.

Any ideas?

Thanks in advance,

CptBBQ

[CarlGustaffa 4]

Are you aware that 80m/s equals 288km/h? The command setVelocity works with m/s as unit. Then again, I'm not sure what is intended.

[nuxil 2]

CptBBQ what you do ther is only to add in a little Push. what i mean you only increse the speed once.

what you need is a kind of loop

example

while {true} do
{
   if (TURBO_KEY) then
   {
       _vel = velocity _vehicle;
       _dir = direction _vehicle;
      _speed = 1;
      _vehicle setVelocity [(sin _dir*_speed),(cos _dir*_speed),(_vel select 2)]; 
   };
   sleep 0.1;
};

where you probealy want TURBO_KEY set by a displayevent handler on a spesific key,

press down on Lsift sets TURBO_KEY as true

and releasing the button sets TURBO_KEY as false

[CptBBQ 10]

Thanks guys!

Your answers explain why the motorcycle takes off like a rocket while the heavier car won´t move much at all. So, I´ll experiment with a loop and see what happens.

Maybe there´s a better way to achieve what I intended. So I´ll explain a little..

The vehicles will be driven by civilian AI´s which, at some point in a mission, will head towards the closest blufor troops and blow them self up when they are close enough.

For the movement I used the 'doMove' command. This worked fine for pedestrians, but AI in a vehicle will not come closer than 20-30m to it´s target. So at that point I let kick in the acceleration, which was enough to nudge the motorcycle towards it´s target.

As I´ve just learned, a much heavier vehicle will take a whole different kinetic impulse to reach it´s target. But of course, I want to control both (and maybe even more) vehicles with the same script.

So, maybe the doMove command is more of a problem than the relative acceleration code.

I´m still learning and always thankful for a insight on how others would solve the same problems.

Cheers,

CptBBQ

EDIT: Executing the code within a loop results in a very choppy, "laggy" movement. Looks like the car goes right back to its original velocity after every loop.

I think I need to take a different approach...

Edited October 30, 2010 by CptBBQ

[nuxil 2]

CptBBQ

if ist laggy/choppy adjust the sleep.

i tested this on a red civilian car on utes,. from star to end.

had 290 Km/H at the end of the runway without any lagg/choppyness

_vehicle = _this;
while {true} do
{
   if (TURBO_KEY) then
   {
       _vel = velocity _vehicle;
       _dir = direction _vehicle;
      _speed = 1;
      _vehicle setVelocity [(_vel select 0)+(sin _dir*_speed),(_vel select 1)+ (cos _dir*_speed),(_vel select 2)];
   };
   sleep 0.01;
};

i just used 2 tradio triggers to set TURBO_KEY true/false

PS. Make the SetVelocity the same way as in the biki example. dont take out part of it.

[CptBBQ 10]

Thanks nuxil!

The "sleep 0.01" did the trick. I´ll just have to adjust _speed depending on the vehicle. But that´ll be just a little trial and error.

:bounce3:

Cheers,

Bbq