Any ideas on how to make this code efficient? - performance

Question

The code:
local RunService = game:GetService("RunService")
local Player = game.Players:GetPlayerFromCharacter(script.Parent)
local Character = Player.Character or Player.CharacterAdded:Wait()
local PartDimensions = Vector3.new(2048,512,2048)
local WaterPart = Instance.new("Part")
WaterPart.Size = PartDimensions
WaterPart.CFrame = CFrame.new(Character.HumanoidRootPart.Position.X,-2048,Character.HumanoidRootPart.Position.Z)
WaterPart.Material = Enum.Material.Foil
WaterPart.CanCollide = false
WaterPart.Parent = game.Workspace
WaterPart.Anchored = true
WaterPart.Transparency = 1
Character.Humanoid.Died:Connect(function()
WaterPart:Destroy()
end)
RunService.Stepped:Connect(function(step)
WaterPart.CFrame = CFrame.new(Character.HumanoidRootPart.Position.X,0,Character.HumanoidRootPart.Position.Z)
workspace.Terrain:FillBlock(WaterPart.CFrame, WaterPart.Size, Enum.Material.Water)
I made an code to generate water
I expected it to work good enough
The code almost crashes the server

Answer 1

Before we can discuss efficiency, we need to talk about what work is actually happening.
When you generate terrain, you provide a region and a terrain type, and the engine marches over all of the voxels in that region and replaces the terrain. It then has to regenerate a 3D mesh to encompass that region. These are fairly expensive operations to begin with.
I believe each voxel in the world is about 0.4 x 0.4 x 0.4 studs^3. So when you say that you want to fill a region that is 2048 x 512 x 2048 studs^3, you are telling the engine to march over 33,554,432,000 voxels. And you are telling the engine to do this operation every single time the engine ticks.
So to make this more performant, there are some thing you can consider :
1. Do less work every tick
Consider reducing the dimensions of the WaterPart. The engine is strong enough to regenerate terrain in real time, but only to a certain point. If you reduce the size of the region to change, the engine will have less voxels to update, and it will have less work to do every step of the engine.
local PartDimensions = Vector3.new(20, 5, 20)
2. Do work less frequently
Like I said earlier, the engine should be able to handle real-time changes to terrain, but you can also reduce the frequency that terrain is updated. RunService.Stepped fires on every tick before the physics simulation kicks off, and it provides arguments for how long it has been since the last tick. You can use this to throttle how often the terrain is actually updated :
local timeSinceLastUpdate = 0.0 -- seconds
local UPDATE_FREQUENCY = 0.2 -- seconds
RunService.Stepped:Connect(function(step, deltaTime)
-- limit updates to 5 times per second
timeSinceLastUpdate += deltaTime
if timeSinceLastUpdate >= UPDATE_FREQUENCY then
-- reset the counter
timeSinceLastUpdate = 0.0
-- do the thing
WaterPart.CFrame = ...
workspace.Terrain:FillBlock(...)
end
end)
3. Do the work ahead of time
You should ask yourself if this work needs to done in real time. While this won't immediately improve performance, you can reduce the amount of work done by "pre-filling" the spawning area. If you know players are going to spawn at (0, 0, 0), then manually fill in the (2048, 512, 2048) region at (0, -2048, 0) at the start of the game, or simply bake it into the level. Then, you can pair that with...
4. Only update the terrain when you need to
You can limit the impact of terrain generation by only adding terrain when you need to. Consider saving the dimensions of the terrain you've already added, and only add more terrain as players approach the edges.