Deterministic¶
You game logic must be deterministic to the bit-level. The FrameSync library only sends and manages players inputs. This means that given the same input, your game logic should produce the exact same game states on all supported platforms.
Challenages to Achieve Cross-platform Deterministic¶
- Floating point: nearly impossible to have deterministic floating point calculation on different machines.
- Physics Engine: Most physics engines use floating point so they are not deterministic on different machines.
- Other Tools: Similar to the physics engines, probably all the tools that you currently use (Navigation, Animatior, StateMachine, BehaviourTree, etc...) are not deterministic on different machines.
FixedMath¶
FrameSync provides a fixed point math library FixedMath which is cross-platform deterministic.
| FixedMath | Unity |
|---|---|
| FMath | Mathf |
| FFloat | float |
| FVector2 | Vector2 |
| FVector3 | Vector3 |
| FVector4 | Vector4 |
| FMatrix4x4 | Matrix4x4 |
| FQuaternion | Quaternion |
| FTransform | Transform |
You can use it to replace float, Vector2, Vector3, Quaternion, Matrix4x4, Mathf, and the Transform component to implment your game logic.
FPhyscis¶
Cross-platform deterministic 2D and 3D physics engines which run on the FixedMath library. They are designed to be used with the FrameSync library.
Deterministic Execution Order¶
You can implement your game logic in the IFrameSync interfaces as their update order is guarenteed deterministic.