Racing car game in Armory engine

danilk · April 13, 2019, 7:58am

Hello,

Just in some addition on top of @zicklag’s topic and my experience on vehicle physics in Armory.

Armory uses Bullet physics. It does support an out of box vehicle behaviors. However, for racing game that demands cars to drive at high speed, additional tweaks and setups maybe need to done to stabilize the vehicle, otherwise strange behaviors (like car flies off to air in strange rotation ways). It was not armory specific, but just due to how Bullet physics work. But maybe that is the desired behavior for a game too.

Other as mention in previous post, some very detail function may not be bind yet from bullet physics (such as very specific detail rotation and contact object), though there are way to bind it, or at least workaround through other ways. zicklag’s PR will definitely make things much easier used to do these additional bindings for bullet and take trial/error approaches.

Regarding the loading of tracks/other objects. My experience with it is Armory can load quite many objects in scene with decent speed if they are just graphics (no physics) and it seem to able to do backface culling well to save resources. The problem will be on physics. The moment you add a lot of of objects with complex mesh (especially psychic object generated from 3d object mesh), the performance will really slow down (and seem physics will always be there, one way maybe implemented own way to turn off on very far distances so it saves up resources). My resolution was actually create another simpler invisible mesh beside the graphic mesh, so the physics is there to some degree with decent graphics (like road wall)

Armory does come with a vehicle sample (which you maybe already familiar with)
GitHub - armory3d/armory_templates: Starter Scenes → vehicle

There is also a small doc on notes I putted together base on my experience with vehicle setup in Armory (please feel free to correct if there are any mistakes)

github.com

armory3d/armory_docs/blob/main/getting_started/vehicle.md

# Vehicle Setup

This docs is based on [Panda3D Bullet Vehicle Doc](https://www.panda3d.org/manual/index.php/Bullet_Vehicles) with additional topics to cover some of common faced problems

This article discussed the out of box Bullet Physics implementation of vehicle, which is based on raycast vehicle. The benefit of this type of vehicle is it is easier to implement vs constraint type vehicle.

This approach is used in some of arcade games. 

Following articles go over the high level of the vehicle template implementation and provide some optional suggestions (as these suggestions are not generics across every type of implementations)

The initial vehicle template setup can be found in vehicle in [Armory3D Templates](https://github.com/armory3d/armory_templates)

In `vehicle` object, there is a script tight to it

### Setup Vehicle

Following codes did following
Get all the wheels object in the scene according to their names and pushes into an array
```
for (n in wheelNames) {

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A demo of a vehicle game (disclaimer, Armory should able to do much better in graphics, it was my model skills that limit it :))