flatbuffers

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-- need to update the Lua path to point to the local flatbuffers implementation
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package.path = string.format("../lua/?.lua;%s",package.path)
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package.path = string.format("./lua/?.lua;%s",package.path)
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-- require the library
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local flatbuffers = require("flatbuffers")
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local binaryArray = flatbuffers.binaryArray-- for hex dump utility
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-- require the files generated from the schema
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local weapon = require("MyGame.Sample.Weapon")
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local monster = require("MyGame.Sample.Monster")
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local vec3 = require("MyGame.Sample.Vec3")
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local color = require("MyGame.Sample.Color")
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local equipment = require("MyGame.Sample.Equipment")
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-- get access to the builder, providing an array of size 1024
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local builder = flatbuffers.Builder(1024)
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local weaponOne = builder:CreateString("Sword")
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local weaponTwo = builder:CreateString("Axe")
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-- Create the first 'Weapon'
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weapon.Start(builder)
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weapon.AddName(builder, weaponOne)
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weapon.AddDamage(builder, 3)
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local sword = weapon.End(builder)
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-- Create the second 'Weapon'
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weapon.Start(builder)
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weapon.AddName(builder, weaponTwo)
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weapon.AddDamage(builder, 5)
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local axe = weapon.End(builder)
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-- Serialize a name for our mosnter, called 'orc'
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local name = builder:CreateString("Orc")
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-- Create a `vector` representing the inventory of the Orc. Each number
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-- could correspond to an item that can be claimed after he is slain.
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-- Note: Since we prepend the bytes, this loop iterates in reverse.
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monster.StartInventoryVector(builder, 10)
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for i=10,1,-1 do
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    builder:PrependByte(i)
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end
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local inv = builder:EndVector(10)
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-- Create a FlatBuffer vector and prepend the weapons.
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-- Note: Since we prepend the data, prepend them in reverse order.
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monster.StartWeaponsVector(builder, 2)
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builder:PrependUOffsetTRelative(axe)
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builder:PrependUOffsetTRelative(sword)
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local weapons = builder:EndVector(2)
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-- Create our monster by using Start() andEnd()
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monster.Start(builder)
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monster.AddPos(builder, vec3.CreateVec3(builder, 1.0, 2.0, 3.0))
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monster.AddHp(builder, 300)
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monster.AddName(builder, name)
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monster.AddInventory(builder, inv)
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monster.AddColor(builder, color.Red)
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monster.AddWeapons(builder, weapons)
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monster.AddEquippedType(builder, equipment.Weapon)
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monster.AddEquipped(builder, axe)
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local orc = monster.End(builder)
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-- Call 'Finish()' to instruct the builder that this monster is complete.
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builder:Finish(orc)
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-- Get the flatbuffer as a string containing the binary data
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local bufAsString = builder:Output()
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-- Convert the string representation into binary array Lua structure
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local buf = flatbuffers.binaryArray.New(bufAsString)
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-- Get an accessor to the root object insert the buffer
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local mon = monster.GetRootAsMonster(buf, 0)
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assert(mon:Mana() == 150)
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assert(mon:Hp() == 300)
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assert(mon:Name() == "Orc")
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assert(mon:Color() == color.Red)
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assert(mon:Pos():X() == 1.0)
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assert(mon:Pos():Y() == 2.0)
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assert(mon:Pos():Z() == 3.0)
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for i=1,mon:InventoryLength() do
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    assert(mon:Inventory(i) == i)
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end
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local expected = { 
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    {w = 'Sword', d = 3}, 
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    {w = 'Axe', d = 5}
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}
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for i=1,mon:WeaponsLength() do
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   assert(mon:Weapons(i):Name() == expected[i].w)
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   assert(mon:Weapons(i):Damage() == expected[i].d)
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end
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assert(mon:EquippedType() == equipment.Weapon)
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local unionWeapon = weapon.New()
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unionWeapon:Init(mon:Equipped().bytes,mon:Equipped().pos)
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assert(unionWeapon:Name() == "Axe")
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assert(unionWeapon:Damage() == 5)
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print("The Lua FlatBuffer example was successfully created and verified!")