Gizmo question: How do I create a field of view using gizmos?

I thought maybe I can draw two vectors based off of the character's transform.forward vector (one vector on each side of the transform.forward vector). For example, how would I draw vectors 70 degrees from transform.forward? The middle line represents transform.forward and the two angle lines represent the 70 degree vectors: " \ | / "

var rayRange = 10;
function OnDrawGizmosSelected ()
{
    Gizmos.color = Color.magenta;
    Gizmos.DrawRay (transform.position, transform.forward * rayRange);
}

Thanks!

Try using Quaterion.AxisAngle to create a rotation.

So, something like this:

void OnDrawGizmosSelected()
{
    float totalFOV = 70.0f;
    float rayRange = 10.0f;
    float halfFOV = totalFOV / 2.0f;
    Quaternion leftRayRotation = Quaternion.AngleAxis( -halfFOV, Vector3.up );
    Quaternion rightRayRotation = Quaternion.AngleAxis( halfFOV, Vector3.up );
    Vector3 leftRayDirection = leftRayRotation * transform.forward;
    Vector3 rightRayDirection = rightRayRotation * transform.forward;
    Gizmos.DrawRay( transform.position, leftRayDirection * rayRange );
    Gizmos.DrawRay( transform.position, rightRayDirection * rayRange );
}