Handling 3rd Person Camera Physics with SphereCast's

Hello again internet! Let's dive into how to manage camera physics in your third person cameras using `SphereCast`s.

`SphereCast`'s expand upon what you might know about raycasts projecting a beam through your scene that can detect physical objects in the scene and let you know if it's hit them. Unlike a raycast though a `SphereCast` includes a radius. This can prevent the detection from going through tight spaces or between closely aligned Game Objects.

To showcase this, we're going to build a quick 3rd Person Camera in a scene that has some narrow alleyways. In order to prevent our camera from clipping geometry inside those alleyways and to prevent it from ending up in a narrow space we'll project a sphere using a `SphereCast`. This gives our camera some safety and improves the quality of the camera positioning.

You can find more information about `SphereCast`'s in Unity's documentation here: https://docs.unity3d.com/ScriptRefere...

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The code we wrote in this video is here if you'd like to try it yourself!

```csharp
using UnityEngine;

public class ThirdPersonCamera : MonoBehaviour
{
public float cameraSpeed;
public Transform cameraTransform;
public float cameraDistance;
public float radius = 0.25f;

void Update()
{
// Multiplying quaternions adds them together
this.transform.rotation *= Quaternion.Euler(0, cameraSpeed * Input.GetAxis("Mouse X"), 0);

// Move Camera back until we get near a Physics Collider
Ray ray = new Ray(this.transform.position, -this.transform.forward);
RaycastHit hit;
if (Physics.SphereCast(ray, radius, out hit, cameraDistance))
{
cameraTransform.localPosition = Vector3.back * hit.distance;
}
else
{
cameraTransform.localPosition = Vector3.back * cameraDistance;
}
}

// Draw a Gizmo around where the camera has been projected to.
void OnDrawGizmos()
{
Gizmos.color = Color.blue;
Gizmos.DrawWireSphere(cameraTransform.position, radius);
}
}

```

Looking for an introduction to `Raycast`s? Check out my video on Raycasting in Unity: https://worldofzero.com/videos/detect...

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