Trying to create fog in the world.

Hello, I am currently trying to display fog in the world but it doesn't show up. Anyone know why?

@SubscribeEvent
@SideOnly(Side.CLIENT)
public void onTick(final TickEvent.ClientTickEvent event)
{
    final Minecraft mc = Minecraft.getMinecraft();
    if (mc.player != null)
    {
        if (ClientEventSubscriber.fogDensity > ClientEventSubscriber.fogRequiredDensity)
        {
            ClientEventSubscriber.fogDensity -= 1.0E-4F;
        } else if (ClientEventSubscriber.fogDensity < ClientEventSubscriber.fogRequiredDensity)
        {
            ClientEventSubscriber.fogDensity += 4.0E-4f;
        }
    }
}

@SubscribeEvent
@SideOnly(Side.CLIENT)
public void onFog(final EntityViewRenderEvent.FogDensity event)
{
    final Minecraft mc = Minecraft.getMinecraft();
    if (mc.world.isRaining())
    {
        ClientEventSubscriber.fogRequiredDensity = 0.1f;
    } else
    {
        ClientEventSubscriber.fogRequiredDensity = 0.015f;
    }
    BigDecimal bd = new BigDecimal(Float.toString(ClientEventSubscriber.fogDensity));
    bd = bd.setScale(3, 4);
    event.setDensity(bd.floatValue());
    GL11.glFogi(2917, 2048);
    event.setCanceled(true);
}