stride3d.stride-docs/en/manual/physics-bullet/simulation.md

Physics simulation

Intermediate Programmer

[!INCLUDE bullet-deprecation]

Stride's physics are controlled by the Simulation class. You can change how Stride initializes the simulation by modifying flags in PhysicsSettings, accessed in the GameSettings asset properties.

[!Note] Your scene must have at least one Collider in order for Stride to initialize the Simulation instance.

• CollisionsOnly initializes the Simulation with collision detection turned on, but no other physics. Objects won't react to physical forces.

• ContinuousCollisionDetection initializes the Simulation with continuous collision detection (CCD). CCD prevents fast-moving entities (such as bullets) erroneously passing through other entities.

[!Note] The SoftBodySupport, MultiThreaded, and UseHardwareWhenPossible flags are currently disabled.

At runtime, you can change some Simulation parameters:

• Gravity — the global gravity, in world units per second squared
• FixedTimeStep — the length of a simulation timestep, in seconds
• MaxSubSteps — the maximum number of fixed timesteps the engine takes per update

See also

• Colliders
• Collider shapes