unity-physics

Development

Unity Physics skill for collision detection, rigidbody dynamics, raycasting, and physics configuration.

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How to use this skill

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Unity Physics Skill

Physics system configuration and implementation in Unity.

Overview

This skill provides capabilities for implementing physics-based gameplay using Unity's physics systems (PhysX 3D and Box2D 2D).

Capabilities

Rigidbody Configuration

Configure mass, drag, constraints
Set up continuous collision detection
Handle interpolation modes
Manage sleep thresholds

Collision Detection

Configure colliders and triggers
Set up collision layers and masks
Handle collision events
Implement compound colliders

Raycasting

Perform raycasts and spherecasts
Use overlap tests
Handle layer filtering
Batch physics queries

Physics Settings

Configure fixed timestep
Set up solver iterations
Handle physics materials
Manage auto-sync transforms

Prerequisites

Unity 2021.3+
Physics module (built-in)

Usage Patterns

Rigidbody Setup

public class PhysicsObject : MonoBehaviour
{
    private Rigidbody rb;

    void Awake()
    {
        rb = GetComponent<Rigidbody>();
        rb.interpolation = RigidbodyInterpolation.Interpolate;
        rb.collisionDetectionMode = CollisionDetectionMode.Continuous;
    }

    void FixedUpdate()
    {
        rb.AddForce(Vector3.forward * 10f, ForceMode.Force);
    }
}

Raycasting

public bool CheckGround(out RaycastHit hit)
{
    return Physics.Raycast(
        transform.position,
        Vector3.down,
        out hit,
        1.1f,
        groundLayer,
        QueryTriggerInteraction.Ignore
    );
}

Best Practices

Use FixedUpdate for physics
Avoid scaling colliders at runtime
Use layers for filtering
Profile physics queries
Consider Physics.autoSyncTransforms

References

Physics Documentation