protected override void LoadContent()
{
sky = new Sky(sim);
sky.LoadContent(sim.Content);
weather = new Weather(sim);
weather.LoadContent();
wildlife = new Wildlife(sim);
wildlife.LoadContent();
lighting = new Lighting(this);
PresentationParameters pp = GraphicsDevice.PresentationParameters;
worldRenderTarget = new RenderTarget2D(GraphicsDevice, pp.BackBufferWidth, pp.BackBufferHeight, 1, SurfaceFormat.Color);
}