Difference between car types

[Slick]

I'm going to do some playing with the car types. A few questions:
What is the difference between the 2 cars in the demos? Is one a ray cast?
How scalable are they both?

[Slick]

Also a secondary question:

Which vehicle is more suited to designing vehicles that aren't cars with 4 wheels? Say you wanted some kind of tracked vehicle?

I just got the sandbox demo running and will look at the code.

I wish there was more documentation on newton 300. I have used 200 for quite a while but can't find features/documentation on 300. Do I just scroll through the headers?

[Julio Jerez]

In many the demos I usually make tow versions, the fist one is a simple, and the second more elaborated.
The car is special because there are so many variations.

The car joint is general, it can make any can of vehicle, nor just car with wheels, yes it can do track vehicle.

not it is no a raycast car it is a full rigid body articulated contraction that take advantage of the special property that the subpart of a vehicle can only have one parent,
therefore a special solver can be implemented that solve the joint in a way the error can be zero out by projection.

the vehicle joint can also stuff like airplane, helicopter, is a vehicle that do not have part that are not interconnected to each other, then the vehicle can do it.
for example It also support attachment like doors, or flaps. although these having vein add yet, but it is very easy.

I will make a demo using a M1A1 tank, but I have no have the time, and also there has not being much interest.

if you want to we can complete the car demo over the weekend and start the Tank demo. There is also a heavy vehicle.

[Slick]

So to help me out are the basic car and super car both from the vehicle joint? Neither of them is raycast? The supercar is the same joint with some extra settings to fine tune it?

What about scaling? If I were to throw 30 of them into a scene would the engine handle it? I remember playing with the vehicle in 1.53 and the fps would degrade because with say 20 vehicles the sim would be cpu limited.

I think I also remember a discussion about raycast being less cpu intensive than the vehicle joint. Is that still true with the new vehicle joint?

If i can help with the M1A1 let me know. I would like that challenge.

[Julio Jerez]

There is not raycast car anymore on Newton 300.
the code was combined with the multi body car joint and now there is a vehicle system, which is implemented as a listener on the engine.

The basics car soudl be a box with 4 wheels, the super car use a mesh and add extra stuff like sound, a track and controllers.

The multi body car on core 200 was the same multi body car on Newton 1.53 with one difference, that solver on the car in core 1.53 was the same exact solver while the solver on the car of core 200 and 300 is an iterative solver that resolve joints error by projection.

The ray cats car has a contact time complexity, the muti body car has a linear time complexity (meaning is proportional to the number of element attached to it, a tank will take longer that a car with four wheels) the car on core 100 was quadratic time complexity

The car on core 300 is not as fast as the raycats car on core 200 but much faster than the car of core 1.53

How many can you place I do not know? there was a demo of core 200 that places 600 ray cast car. I do not think you can place that many with core 300
but I believe that it can handle 40 or 50 four wheel cars easily.
what are you doing?

also the engine can solve the cars in parallel when using multi cores, plus it can run asynchronous.
as long as you have a machine with multicourse, the update is essentially free in Newton 300, check out this demo

[Slick]

Thanks for the quick response. My game focuses on an arcade type tank with reasonable realism. I am shooting for 20 tanks that do not overpower the cpu due to the calculations involved. It doesn't need to be sim level with say 30 wheels per side. I imagine 3 or so wheels per side might do it. My current implementation uses contact forces but it has been tricky and has some sideways sliding at speed. 40 or 50 sounds promising since that should give enough headroom that it isn't cpu limited.