Vehicle model for 3.14

[JoeJ]

Ok, thanks for time and explantation

I looked at the vehicle controller and see it fills an array of NewtonUserContactPoints.
That would work for the single contact ragdoll - but you convinced me it's no good idea.

My main interest in user contacts is a better solution for the realtime scaling body contacts.
The scaling adds velocity to the surface Newton is not aware of, so it does not work out of the box.
Hacking contacts and / or tweaking contact velocities did not work well, so i replace the contacts with custom joints, but i won't be be able to make this as correct as your default contacts.

You also talked about your sticky contacts idea, i think that requires the same functionality.
Is this already possible?

[Julio Jerez]

You also talked about your sticky contacts idea, i think that requires the same functionality. Is this already possible?

no yet, for that I need to add one functionality to the contact joint so that the lower friction force can be shifter by some value, write not that not possible is a joint row is marked as contact normal.
It will be a material option, that will work with that functionality but I am leaving that for newton 3.15

My plan now is this:
-complete the vehicle and make the best I could possible can.
-fix all the bugs
-complete the voronoi and Boolean destruction

that will be the lest of functionality for 3.14 then start 3.15 right away starting with particle bodies.

[Julio Jerez]

Actually Joe,
as I keep debugging this, every thing seem to check out as it should be.
so I modified the demo so that I can make assumption of what to expect.
and I now can see what happen.

Basically is the coefficient of restitution in combination with the pick force and the body size.

what happens is that the pick force is supplying the body with a velocity of 365 m/s
the default coefficient of restitution is in 1.4
what this mean is that the body will bound with 365 * 0.4 = 156 m/s

since the body is abnormally big, that seem like a bug but it is in fact the right respond.
we see as a bug because we are no use to see big object moving so quickly, in general when a large object collide, is does not bounce back it simple keep going and getting destroyed.

I change the coefficient of friction to 1.1 and now is right. I check in the test demo so that you can see.

This is now more pronounce that in previous version because remember when I made the default joint stiffness a lot much stronger, this affect the contact too, if anything this is better behavior than before.

I am not ruling out that there still could be a bug but I do not see it.

[collerblade]

Julio
The new vehicle model is awesome! It is much better than i excepted. Grat!!

collerblade

[Leadwerks]

Do you think this will be 100% ready to use by May 15? I can keep this in our beta build before then, but it needs to go out to release in our new version May 15.

[Julio Jerez]

It is ready now.
the only thing missing is end user tweaks, or calibrations I cannot do myself.

[Leadwerks]

What demo are you guys running? The super car demo just makes the Leadwerks truck float in the air and it rotates the car when I turn the tires.

[Julio Jerez]

oh that ls because like I said on the other post I am now working on the ragdoll system.

to test the car, you can set the gavity back to -10.0 in file
../applications\demosSandbox\sdkDemos\toolBox\PhysicsUtils.h

//#define DEMO_GRAVITY -10.0f
#define DEMO_GRAVITY -0.0f

then you can drive the super car and the tank. for the tank demo I have not plugged the engine yet, but the threads and steering do work as expected. I have not changed the simple car demo yet.

[Leadwerks]

This is great. I love the way the tire slip on the 4x4 works. Is this using a multi-body approach instead of raycasting? Feels much more solid.

[Julio Jerez]

glad you like it.
Yes this is all articulated body physics. No only the tires and the chassis are articulated body but also the transmission, the engine and the differentials are joints or rigid bodies.
This allows for end users to attach accessories to vehicles by using normal joints and rigid bodies, which was very hard on previous versions.

I am looking forward some one using your game engine put it to good use.