engine/bin/data/entities/gui/mainmenu/scripts/menu.lua

Static = {
	values = {},
	get = function( obj )
		if Static.values[""..obj:uid()] == nil then
			Static.values[""..obj:uid()] = {}
		end
		return Static.values[""..obj:uid()]
	end
}

local ent = ent
local scene = entities.currentScene()
local controller = entities.controller()
local camera = controller:getComponent("Camera")
local metadata = ent:getComponent("Metadata")
local masterdata = scene:getComponent("Metadata")

local children = {
	mainText = ent:loadChild("./main-text.json",true),
	circleOut = ent:loadChild("./circle-out.json",true),
	circleIn = ent:loadChild("./circle-in.json",true),
	start = ent:loadChild("./start.json",true),
	quit = ent:loadChild("./quit.json",true),
}

local timer = Timer.new()
if not timer:running() then timer:start() end

local playSound = function( key )
	local url = "/ui/" .. key .. ".ogg"
	local assetLoader = scene:getComponent("Asset")
	assetLoader:cache(ent:formatHookName("asset:Load.%UID%"), string.resolveURI(url))
end
local destination = function( obj, x, y, z )
	local static = Static.get(obj)
	local transform = obj:getComponent("Transform")
	static.from = Vector3f(x or transform.position.x, y or transform.position.y, z or transform.position.z)
end

--[[
pcall( function()
	local metadata = controller:getComponent("Metadata")
	local json = json.readFromFile("./data/entities/player.json");
	controller:callHook("object:UpdateMetadata.%UID%", {
		overlay = json["metadata"]["overlay"]
	})
	camera:update(true);
end )
]]

destination(children.mainText, nil, -2, 0)
destination(children.circleOut, nil, -2, 0)
destination(children.circleIn, nil, 2, 0)
destination(children.start, -1.5, nil, 0)
destination(children.quit, -1.5, nil, 0)

ent:addHook("asset:Load.%UID%", function( json )
	local filename = json["filename"]
	if filename == "" or string.extension( filename ) ~= "ogg" then return false end

	local sfx = ent:getComponent("Audio")
	if not sfx:playing() then sfx:stop() end
	sfx:load( filename )
	sfx:setVolume( masterdata["volumes"]["sfx"] )
	sfx:play()

	return true
end )
if os.arch() == "Dreamcast" then
	ent:bind( "tick", function(self)
		-- circle in
		if children.circleIn:uid() > 0 then
			local transform = children.circleIn:getComponent("Transform")
			transform.orientation = Quaternion.axisAngle( Vector3f(0, 0, 1), time.current() * -0.0125 )
		end
		-- circle out
		if children.circleIn:uid() > 0 then
			local transform = children.circleIn:getComponent("Transform")
			transform.orientation = Quaternion.axisAngle( Vector3f(0, 0, 1), time.current() * 0.0125 )
		end
	end )
else
	ent:bind( "tick", function(self)
		local static = Static.get(self)
		if not static.alpha then
			static.alpha = 0
		end

		metadata["initialized"] = true;
		if  static.alpha >= 1.0 then
			static.alpha = 1.0
		else
			static.alpha = static.alpha + time.delta() * 1.5
		end

		-- make background glow
		local glow = 1 + math.sin(1.25 * time.current()) * 0.125
		metadata["color"][1] = glow
		metadata["color"][2] = glow
		metadata["color"][3] = glow
		metadata["alpha"] = static.alpha;
		self:setComponent("Metadata", metadata)

		camera:update(true);

		-- iterate children in batch
		for k, v in pairs(children) do
			if v:uid() <= 0 then goto continue end

			-- set alpha
			local metadata = v:getComponent("Metadata")
			metadata["alpha"] = static.alpha
			v:setComponent("Metadata", metadata)

			local transform = v:getComponent("Transform")
			local static = Static.get(v)
			-- translation
			if not static.from then goto continue end
			if not static.to then static.to = Vector3f(transform.position) end
			if not static.delta then static.delta = 0 end

			if static.delta >= 1 then
				static.delta = 1
			else
				static.delta = static.delta + time.delta() * 1.5
				transform.position = Vector3f.lerp( static.from, static.to, static.delta )
			end

			::continue::
		end	

		-- circle in
		child = children.circleIn
		if child:uid() > 0 then
			local static = Static.get( child )

			local transform = child:getComponent("Transform")
			local metadata = child:getComponent("Metadata")

			-- rotation
			local speed = metadata["hovered"] and 0.25 or 0.0125
			static.time = (static.time or 0) + time.delta() * -speed
			transform.orientation = Quaternion.axisAngle( Vector3f(0, 0, 1), static.time )
		end
		-- circle out
		child = children.circleOut
		if child:uid() > 0 then
			local static = Static.get( child )

			local transform = child:getComponent("Transform")
			local metadata = child:getComponent("Metadata")

			-- rotation
			local speed = metadata["hovered"] and 0.25 or 0.0125
			static.time = (static.time or 0) + time.delta() * speed
			transform.orientation = Quaternion.axisAngle( Vector3f(0, 0, 1), static.time )
		end
	end )
end