//fov tools
/// <summary>
/// set the fov of the camara, does the background calculation needed
/// </summary>
/// <param name="angle">fov in degrees, fov is set off screen width</param>
public void SetFov(float angle)
{
this.fov = (float)((double)GetScreenWidth() / Math.Tan(StaticTools.DegreesToRadians(angle / 2.0f)));
}