--by pavetr.top/ds

--[[
	Credits:Akabenko - Restoring the shader, adapting to the color of the sun
	Mee - Initial implementation
]]
steamworks.DownloadUGC( "3453386337", function( path )
	game.MountGMA( path )
end)
RunConsoleCommand("spawnmenu_reload")

local shaderName = "VolumetricClouds"

local r_clouds = CreateClientConVar( "r_clouds", "0", false, false, "Enable/Disable Volumetric Clouds.", 0, 1 )
local r_clouds_sunfactor = CreateClientConVar( "r_clouds_sunfactor", "5.5", true, false, "Sun color strange.", 0, 50 )
local r_clouds_speed = CreateClientConVar( "r_clouds_speed", "0.5", true, false, "Volumetric clouds speed.", -5, 5 )
local r_clouds_volume = CreateClientConVar( "r_clouds_volume", "30000", true, false, "Volume of clouds.", 15000, 50000 )
local r_clouds_farz = CreateClientConVar( "r_clouds_farz", "1000", true, false, "Volumetric clouds speed.", 0, 2500 )
local r_clouds_brightness = CreateClientConVar( "r_clouds_brightness", "4", true, false, "Volumetric clouds speed.", 0, 20 )
local r_clouds_boxmaxz = CreateClientConVar( "r_clouds_boxmaxz", "356.125000", true, false, "Volumetric clouds speed.", 0, 600 )
local r_clouds_skyz = CreateClientConVar( "r_clouds_skyz", "950", true, false, "Volumetric clouds speed.", 500, 1000 )

list.Set( "PostProcess", "#r_clouds.name", {
	["icon"] = "gui/postprocess/volumetric_clouds.jpg",
	["convar"] = r_clouds:GetName(),
	["category"] = "#shaders_pp",
	["cpanel"] = function( panel )
		panel:AddControl( "ComboBox", {
			["MenuButton"] = 1,
			["Folder"] = "ssao",
			["Options"] = {
				[ "#preset.default" ] = {
					[ r_clouds:GetName() ] = r_clouds:GetDefault(),
					[ r_clouds_sunfactor:GetName() ] = r_clouds_sunfactor:GetDefault(),
					[ r_clouds_speed:GetName() ] = r_clouds_speed:GetDefault(),
					[ r_clouds_volume:GetName() ] = r_clouds_volume:GetDefault(),
					[ r_clouds_farz:GetName() ] = r_clouds_farz:GetDefault(),
					[ r_clouds_brightness:GetName() ] = r_clouds_brightness:GetDefault(),
					[ r_clouds_boxmaxz:GetName() ] = r_clouds_boxmaxz:GetDefault(),
					[ r_clouds_skyz:GetName() ] = r_clouds_skyz:GetDefault(),
				}
			},
			["CVars"] = {
				r_clouds:GetName(),
				r_clouds_sunfactor:GetName(),
				r_clouds_speed:GetName(),
				r_clouds_volume:GetName(),
				r_clouds_farz:GetName(),
				r_clouds_brightness:GetName(),
				r_clouds_boxmaxz:GetName(),
				r_clouds_skyz:GetName(),
			}
		} )

		panel:AddControl( "CheckBox", {
			["Label"] = "#r_clouds.enable",
			["Command"] = r_clouds:GetName()
		} )

		panel:AddControl( "Slider", {
			["Label"] = "#r_clouds.sunfactor",
			["Command"] = r_clouds_sunfactor:GetName(),
			["Min"] = tostring( r_clouds_sunfactor:GetMin() ),
			["Max"] = tostring( r_clouds_sunfactor:GetMax() ),
			["Type"] = "Float",
			["Help"] = true
		} )

		panel:AddControl( "Slider", {
			["Label"] = "#r_clouds.speed",
			["Command"] = r_clouds_speed:GetName(),
			["Min"] = tostring( r_clouds_speed:GetMin() ),
			["Max"] = tostring( r_clouds_speed:GetMax() ),
			["Type"] = "Float",
			["Help"] = true
		} )


		panel:AddControl( "Slider", {
			["Label"] = "#r_clouds.volume",
			["Command"] = r_clouds_volume:GetName(),
			["Min"] = tostring( r_clouds_volume:GetMin() ),
			["Max"] = tostring( r_clouds_volume:GetMax() ),
			["Type"] = "Float",
			["Help"] = true
		} )

		panel:AddControl( "Slider", {
			["Label"] = "#r_clouds.farz",
			["Command"] = r_clouds_farz:GetName(),
			["Min"] = tostring( r_clouds_farz:GetMin() ),
			["Max"] = tostring( r_clouds_farz:GetMax() ),
			["Type"] = "Float",
			["Help"] = true
		} )

		panel:AddControl( "Slider", {
			["Label"] = "#r_clouds.brightness",
			["Command"] = r_clouds_brightness:GetName(),
			["Min"] = tostring( r_clouds_brightness:GetMin() ),
			["Max"] = tostring( r_clouds_brightness:GetMax() ),
			["Type"] = "Float",
			["Help"] = true
		} )

		panel:Help( "#r_clouds.positions" )

		panel:AddControl( "Slider", {
			["Label"] = "#r_clouds.boxmaxz",
			["Command"] = r_clouds_boxmaxz:GetName(),
			["Min"] = tostring( r_clouds_boxmaxz:GetMin() ),
			["Max"] = tostring( r_clouds_boxmaxz:GetMax() ),
			["Type"] = "Float",
			["Help"] = true
		} )

		panel:AddControl( "Slider", {
			["Label"] = "#r_clouds.skyz",
			["Command"] = r_clouds_skyz:GetName(),
			["Min"] = tostring( r_clouds_skyz:GetMin() ),
			["Max"] = tostring( r_clouds_skyz:GetMax() ),
			["Type"] = "Float",
			["Help"] = true
		} )

	end
} )

local volume_mat = Material("pp/volumetric_clouds")

local sky_pos = Vector(0,0,950)
local world_size = 32768

local function RenderVolumetricClouds()
	render.UpdateScreenEffectTexture(1)
	render.OverrideDepthEnable( true, false ) 

    cam.Start3D( vector_origin, EyeAngles() )
        render.SetMaterial( volume_mat )
        render.DrawQuadEasy( sky_pos, vector_up, world_size, world_size, color_white, 0 )
    cam.End3D()

    render.OverrideDepthEnable( false, false )
end

local IsValid = IsValid

local function ThinkVolumetricClouds()
	local Sun = ents.FindByClass("class C_Sun")[1]
    local sun = util.GetSunInfo()

    --if !sun then return end

    local sun_angle = sun.direction:Angle()

    volume_mat:SetFloat("$c1_w", sun.direction.x)
	volume_mat:SetFloat("$c2_x", sun.direction.y)
	volume_mat:SetFloat("$c2_y", sun.direction.z)

    if IsValid(Sun) then
        local sun_color = Sun:GetColor()
        volume_mat:SetFloat("$c2_z", sun_color.r/255)
		volume_mat:SetFloat("$c2_w", sun_color.g/255)
		volume_mat:SetFloat("$c3_x", sun_color.b/255)
    end
end

cvars.AddChangeCallback( r_clouds:GetName(), function( convar_name, _, identifier )
	local enabled = identifier == "1"

	if enabled then
		hook.Add("PostDraw2DSkyBox", shaderName, RenderVolumetricClouds)

		local sun = util.GetSunInfo()
    	if !sun then return end

		hook.Add("Think", shaderName, ThinkVolumetricClouds)
	else
		hook.Remove("PostDraw2DSkyBox",shaderName)
		hook.Remove("Think", shaderName)
	end
end, shaderName )

cvars.AddChangeCallback( r_clouds_sunfactor:GetName(), function( convar_name, _, identifier )
	volume_mat:SetFloat("$c3_y", identifier)
end, shaderName )

cvars.AddChangeCallback( r_clouds_speed:GetName(), function( convar_name, _, identifier )
	volume_mat:SetFloat("$c3_z", identifier)
end, shaderName )

cvars.AddChangeCallback( r_clouds_volume:GetName(), function( convar_name, _, identifier )
	volume_mat:SetFloat("$c3_w", identifier)
end, shaderName )

cvars.AddChangeCallback( r_clouds_farz:GetName(), function( convar_name, _, identifier )
	volume_mat:SetFloat("$c1_y", identifier)
end, shaderName )

cvars.AddChangeCallback( r_clouds_brightness:GetName(), function( convar_name, _, identifier )
	volume_mat:SetFloat("$c1_x", identifier)
end, shaderName )

cvars.AddChangeCallback( r_clouds_brightness:GetName(), function( convar_name, _, identifier )
	volume_mat:SetFloat("$c1_x", identifier)
end, shaderName )

local s = Vector(world_size,world_size,12.7)

cvars.AddChangeCallback( r_clouds_boxmaxz:GetName(), function( convar_name, _, identifier )
	volume_mat:SetFloat("$c1_z", tonumber(identifier) * s.z)
end, shaderName )

cvars.AddChangeCallback( r_clouds_skyz:GetName(), function( convar_name, _, identifier )
	sky_pos.z = tonumber(identifier)
	hook.Add("PostDraw2DSkyBox", shaderName, RenderVolumetricClouds)
end, shaderName )

--local box_min = Vector(-1, -1, 0)
--local box_max = Vector(1, 1, 356.125000)

--volume_mat:SetFloat("$c0_y", box_min.x * s.x)
--volume_mat:SetFloat("$c0_z", box_min.y * s.y)

--volume_mat:SetFloat("$c1_z", box_max.z * s.z)