Platform creator

Platform.lua

-- Platform
-- Crazyman32
-- November 6, 2018

--[[
	
	This should be a LocalScript within StarterCharacterScripts.
	
	This creates platform parts as the player runs around. It does
	not replicate the platforms to other players. So only the local
	player will see his/her platform, and will not see the platform
	of other players.
	
	This was created just for fun. Feel free to use it however you
	would like. I hope it serves a good educational purpose.
	
--]]



local root = script.Parent:WaitForChild("HumanoidRootPart")
local platforms = {}
local rng = Random.new()

-- Y position of the platform:
local POS_Y = 20

local FADE_IN_DURATION  = 0.25
local FADE_OUT_DURATION = 0.50

-- Platform part:
local platformPrefab = Instance.new("Part")
	platformPrefab.Name = "Platform"
	platformPrefab.Anchored = true
	platformPrefab.Locked = true
	platformPrefab.TopSurface = Enum.SurfaceType.Smooth
	platformPrefab.BottomSurface = Enum.SurfaceType.Smooth
	platformPrefab.Material = Enum.Material.Grass
	platformPrefab.Color = Color3.fromRGB(138, 171, 133)
	platformPrefab.Size = Vector3.new(16, 8, 16)

local platformSize = platformPrefab.Size.X

-- Folder in which platforms go into:
local platformFolder = workspace:FindFirstChild("Platforms")
if (platformFolder) then
	platformFolder:ClearAllChildren()
else
	platformFolder = Instance.new("Folder")
	platformFolder.Name = "Platforms"
	platformFolder.Parent = workspace
end


local function Round(x, mult)
	return math.floor((x / mult) + 0.5) * mult
end


local function FadeIn(part, callback)
	local info = TweenInfo.new(FADE_IN_DURATION, Enum.EasingStyle.Quint, Enum.EasingDirection.Out)
	local cfEnd = part.CFrame
	local cfStart = cfEnd + Vector3.new(rng:NextNumber(-40, 40), -10, rng:NextNumber(-40, 40))
	part.CFrame = cfStart
	local tween = game:GetService("TweenService"):Create(part, info, {
		Transparency = 0;
		CFrame = cfEnd;
	})
	tween.Completed:Connect(callback)
	tween:Play()
end


local function FadeOut(part, callback)
	local info = TweenInfo.new(FADE_OUT_DURATION, Enum.EasingStyle.Quint, Enum.EasingDirection.In)
	local tween = game:GetService("TweenService"):Create(part, info, {
		Transparency = 1;
		CFrame = part.CFrame + Vector3.new(0, -10, 0);
	})
	tween.Completed:Connect(callback)
	tween:Play()
end


-- Create and manage a single platform piece:
local function CreatePlatform(pos)
	
	local key = tostring(pos.X) .. ":" .. tostring(pos.Z)
	if (platforms[key]) then return end
	platforms[key] = true
	
	local platform = platformPrefab:Clone()
	platform.CFrame = CFrame.new(pos)
	platform.Transparency = 1
	platform.Parent = platformFolder
	
	local temp = platform:Clone()
	temp.Parent = platformFolder
	
	FadeIn(platform, function()
		temp:Destroy()
		local heartbeat
		local removalDistance = (platformSize * 2)
		
		-- Wait for part to be too far away, and then fade it out:
		heartbeat = game:GetService("RunService").Heartbeat:Connect(function()
			if ((platform.Position - root.Position).Magnitude > removalDistance) then
				heartbeat:Disconnect()
				platforms[key] = nil
				FadeOut(platform, function()
					platform:Destroy()
				end)
			end
		end)
		
	end)
	
end


-- Run step each frame:
local function Step()
	
	-- Project forward based on the movement velocity (if not moving, just use direction player is facing)
	local unit = (root.Velocity.Magnitude < 0.01 and root.CFrame.LookVector or root.Velocity.Unit)
	local projectedPos = root.Position + (unit * (platformSize * 1.5))
	
	-- Round projected position to the size of the platform:
	local x = Round(projectedPos.X, platformSize)
	local z = Round(projectedPos.Z, platformSize)
	local pos = Vector3.new(x, POS_Y, z)
	
	-- Create platform at current player position AND projected next position:
	CreatePlatform(Vector3.new(Round(root.Position.X, platformSize), POS_Y, Round(root.Position.Z, platformSize)))
	CreatePlatform(pos)
	
end


game:GetService("RunService").Heartbeat:Connect(Step)