Abyss Custom Sky v1

// Abyss custom sky stuff
local skypaint
local sun

hook.Add("InitPostEntity", "SkyPaint", function()
    if SERVER then
        RunConsoleCommand("sv_skyname", "painted")
        local skypaints=ents.FindByClass("env_skypaint")
        if #skypaints==0 then
            skypaint = ents.Create("env_skypaint")
            skypaint:Spawn()
            skypaint:Activate()
        elseif #skypaints >= 1 then
            skypaint=skypaints[1]
        end
        local suns=ents.FindByClass("env_sun")
        if #suns >= 1 then
            sun=suns[1]
        end
    end
end)

/*
local function UpdateDusk(p)
    print(p)
    if p > 135 and p < 225 then
        skypaint:SetDuskIntensity( p/36 )
        print(p/36)
    elseif p > 360 and p < 450 then
        if p > 360 and p < 405 then
            skypaint:SetDuskIntensity( p/81 )
            print(p/81)
        else
            skypaint:SetDuskIntensity( p/81 )
            print( p/81 )
        end
    else
        skypaint:SetDuskIntensity( 0 )
        print(0)
    end
end
*/

local function SetSunAngle(ang)
    sun:SetKeyValue( "sun_dir", tostring( ang:Forward() ) )
    //UpdateDusk(ang.p)
end

local function SetSkyColor(top,bottom)
    skypaint:SetTopColor( top )
    skypaint:SetBottomColor( bottom )
end

local function UpdateSky(time)
    local day={}
    day.top=Vector( 0.2, 0.5, 1.0 )
    day.bottom=Vector( 0.8, 1.0, 1.0 )

    local night={}
    night.top=Vector( 0, 0, 0 )
    night.bottom=Vector( 0, 0, 0 )

    local lerptime=math.sqrt((100-(100/12)*time)^2)/100
    local top=LerpVector(lerptime, day.top, night.top)
    local bottom=LerpVector(lerptime, day.bottom, night.bottom)
    SetSkyColor(top,bottom)
end

local function UpdateSun(time)
    SetSunAngle(Angle((time*15)+90,0,0))
end

local function round(num, idp)
    local mult = 10^(idp or 0)
    return math.floor(num * mult + 0.5) / mult
end

local function round(n, mult)
    mult = mult or 1
    return math.floor((n + mult/2)/mult) * mult
end

local function UpdateLighting(time)
    local L={"a","b","c","d","e","f","g","h","i","j","k","l"}
    local n=round(-math.sqrt((11-(11/12)*time)^2)+12)
    engine.LightStyle(0,L[n])
    timer.Simple(0.5,function()
        umsg.Start("UpdateLighting")
        umsg.End()
    end)
end

usermessage.Hook("UpdateLighting",function()
    render.RedownloadAllLightmaps()
end)

if SERVER then
    timer.Create("UpdateSky", 60, 0, function()
        local time=os.date("%H")+(os.date("%M")*(1+(2/3))/100)
        UpdateSky(time)
        if IsValid(sun) then
            UpdateSun(time)
        end
        UpdateLighting(time)
    end)
end

function UpdateSkyManual(time)
    UpdateSky(time)
    if IsValid(sun) then
        UpdateSun(time)
    end
    UpdateLighting(time)
end