-- Original by Roblox.  Edited by ArceusInator to include water.

-- Local function definitions
local c = game.Workspace.Terrain
local SetCell = c.SetCell
local GetCell = c.GetCell
local SetCells = c.SetCells
local AutoWedge = c.AutowedgeCells


-----------------
--DEFAULT VALUES-
-----------------
loaded = false
xpos = 0
zpos = 0
width = 512
length = 512
a = 30
f = 8
on = false




---------------
--PLUGIN SETUP-
---------------
self = PluginManager():CreatePlugin()
self.Deactivation:connect(function()
    Off()
end)
toolbar = self:CreateToolbar("Terrain")
toolbarbutton = toolbar:CreateButton("", "Terrain Generator", "terrain.png")
toolbarbutton.Click:connect(function()
    if on then
        Off()
    elseif loaded then
        On()
    end
end)




-----------------------
--FUNCTION DEFINITIONS-
-----------------------

--makes a column of blocks from 1 up to height at location (x,z) in cluster c
function coordHeight(x, z, height)
    SetCells(c, Region3int16.new(Vector3int16.new(x, 1, z), Vector3int16.new(x, height, z)), 1, 0, 0)
end

--makes a heightmap for a layer of mountains (width x depth)
--with a width frequency wf and depthfrequency df (width should be divisible by wf, depth should be divisible by df) (for unsquished results, width/wf = depth/df)
--with a range of amplitudes between 0 and a
function mountLayer(width, depth, wf, df, a)
    local heightmap = {}
    for i = 0, width-1 do
        heightmap[i] = {}
        for k = 0, depth-1 do
            heightmap[i][k] = 0
        end
    end
    math.randomseed(tick())
    local corners = {}
    for i = 0,wf do
        corners[i] = {}
        for k = 0, df do
            corners[i][k] = a*math.random()
        end
    end
    for i = 0, wf do
        corners[i][0] = 0
        corners[i][math.floor(df)] = 0
    end
    for k = 0, df do
        corners[0][k]=0
        corners[math.floor(wf)][k]=0
    end

    for i = 0, width-(width/wf), width/wf do
        for k = 0, depth-(depth/df), depth/df do
            local c1 = corners[i/(width/wf)][k/(depth/df)]
            local c2 = corners[i/(width/wf)][(k+depth/df)/(depth/df)]
            local c3 = corners[(i+width/wf)/(width/wf)][k/(depth/df)]
            local c4 = corners[(i+width/wf)/(width/wf)][(k+depth/df)/(depth/df)]
            for x = i, i+(width/wf)-1 do
                for z = k, k+(depth/df)-1 do
                    local avgc1c3 = (math.abs(x-i)*c3 + math.abs(x-(i+width/wf))*c1)/(width/wf)
                    local avgc2c4 = (math.abs(x-i)*c4 + math.abs(x-(i+width/wf))*c2)/(width/wf)
                    local avg = math.floor((math.abs(z-k)*avgc2c4 + math.abs(z-(k+depth/df))*avgc1c3)/(depth/df))
                    if (avg > 100) then
                        print(avg)
                        avg = 1
                    end
                    heightmap[x][z]= avg
                end
            end
        end
    end
    return heightmap
end

--makes a shell around block at coordinate x, z using heightmap
function makeShell(x, z, heightmap, shellheightmap)
    local originalheight = heightmap[x][z]
    for i = x - 1, x + 1 do
        for k = z - 1, z + 1 do
            if shellheightmap[i][k] < originalheight then
                for h = originalheight, shellheightmap[i][k] - 2, -1 do
                    if h > 0 then
                        SetCell(c, i, h, k, 1, 0, 0)
                    end
                end
                shellheightmap[i][k] = originalheight
            end
        end
    end
    return shellheightmap
end


function onGenerate()
    generate.BorderColor3 = Color3.new(0, 0, 0)
    generate.BackgroundColor3 = Color3.new(0.5, 0.5, 0.5)
    generate.BackgroundTransparency = 0.5
    frame.Visible = false
    toolbarbutton:SetActive(false)
    on = false
    if g:FindFirstChild("gload") == nil then
        gload = Instance.new("Frame", g)
        gload.Name = "gload"
        gload.Position = UDim2.new(0.4, 0, 0.025, 0)
        gload.Size = UDim2.new(0.2, 0, 0.05, 0)
        gload.BackgroundTransparency = 0.5
        gfill = Instance.new("Frame", gload)
        gfill.Name = "gfill"
        gfill.Position = UDim2.new(0, 0, 0, 0)
        gfill.Size = UDim2.new(0, 0, 1, 0)
        gfill.BackgroundColor3 = Color3.new(1, 0.25, 0)
        gfill.BackgroundTransparency = 0.5
        gloadstatus = Instance.new("TextLabel", gload)
        gloadstatus.Position = UDim2.new(0.4, 0, 0.4, 0)
        gloadstatus.Size = UDim2.new(0.2, 0, 0.2, 0)
        gloadstatus.Text = ""
        gloadstatus.BackgroundColor3 = Color3.new(0.4, 0.4, 0.4)
        gloadstatus.TextColor3 = Color3.new(1, 1, 1)
        gloadstatus.Font = Enum.Font.ArialBold
        gloadstatus.FontSize = Enum.FontSize.Size14
        gloadstatus.BorderColor3 = Color3.new(0, 0, 0)
        gloadstatus.BackgroundTransparency = 1
    else
        gload = g:FindFirstChild("gload")
        gfill = gload:FindFirstChild("gfill")
        gload.Visible = 1
        gfill.Visible = 1
        gfill.Size = UDim2.new(0, 0, 1, 0)
        gloadstatus.Text = ""
    end

    --Generate Terrain
    -- offset terrain additionally by whatever the smallest cell is
    --xpos2 = xpos + game.Workspace.Terrain.MaxExtents.Min.X
    --zpos2 = zpos + game.Workspace.Terrain.MaxExtents.Min.Z
    xpos2 = xpos - width/2
    zpos2 = zpos - length/2

    -- "bump" camera up to 200 studs if it was not before
    if game.Workspace.CurrentCamera.CoordinateFrame.p.Y < 200 then game.Workspace.CurrentCamera.CoordinateFrame = game.Workspace.CurrentCamera.CoordinateFrame + Vector3.new(0, 200 - game.Workspace.CurrentCamera.CoordinateFrame.p.Y, 0) end

    --make 3 layers of mountains (you can change the frequency and amplitude of each layer and add or remove layers as you see fit (but don't forget to add the new layers to the loop below)
    a1 = mountLayer(width, length, f*width/512, f*length/512, 3/5*a)
    a2 = mountLayer(width, length, 2*f*width/512, 2*f*length/512, 2/5*a)
    heightmap = {}
    for x = 0, width - 1 do
        heightmap[x + xpos2] = {}
        for z = 0, length - 1 do
            heightmap[x + xpos2][z + zpos2] = a1[x][z] + a2[x][z]
        end
    end
    shellheightmap = {}
    for x = 0, width - 1 do
        shellheightmap[x + xpos2] = {}
        for z = 0, length - 1 do
            shellheightmap[x + xpos2][z + zpos2] = heightmap[x + xpos2][z + zpos2]
        end
    end
    gprogress = 0
    gloadstatus.Text = "Generating Terrain Shape..."
    k = 1 + zpos2

    local waitCount = 0

    while k < length - 1 + zpos2 do
        for x = 1 + xpos2, width - 2 + xpos2 do
            coordHeight(x, k, heightmap[x][k])
            shellheightmap = makeShell(x, k, heightmap, shellheightmap)
        end
        k = k + 1
        gprogress = gprogress + 2/(length * 3)
        gfill.Size = UDim2.new(gprogress, 0, 1, 0)
        if waitCount > 5 then waitCount = 0 wait(0.01) else waitCount = waitCount + 1 end
    end
    gloadstatus.Text = "Smoothing Terrain..."
    k = 1 + zpos2
    waitCount = 0
    local maxHeight = -1
    local oldK = k
    while k < length - 1 + zpos2 do
        for x = 1 + xpos2, width - 2 + xpos2 do
            height = shellheightmap[x][k]
            if height == nil then
                height = -1
            end
            if height > maxHeight then
                maxHeight = height
            end
        end
        k = k + 1
        gprogress = gprogress + 1/(length * 3)
        gfill.Size = UDim2.new(gprogress, 0, 1, 0)
        if waitCount > 10 then
            waitCount = 0
            AutoWedge(c, Region3int16.new(Vector3int16.new(1 + xpos2, 0, oldK), Vector3int16.new(width - 2 + xpos2, maxHeight, k)))
            oldK = k+1
            maxHeight = -1
            wait()
        else waitCount = waitCount + 1 end
        if k == length - 2 + zpos2 then
            AutoWedge(c, Region3int16.new(Vector3int16.new(1 + xpos2, 0, oldK), Vector3int16.new(width - 2 + xpos2, maxHeight, k)))

            gfill.Parent.Visible = false
            gfill.Visible = false
        end
    end
    gloadstatus.Text = "Watering Land..."
    gfill.BackgroundColor3 = Color3.new(0,0,1)

    for v = 1,4 do
        for x = 1, width do
            assert(coroutine.resume(coroutine.create(function()
            for z = 1, length do
                wait()
                for y = 1, 5 do
                    if tostring(workspace.Terrain:GetCell(x,20-y,z)) == "Enum.CellMaterial.Empty" then
                        game:GetService("WaterRegionOwners"):AddWaterAt(v == 2 and -x or v == 4 and -x or x-1,20-y,v == 3 and -z or v == 4 and -z or z-1)
                    end
                end
            end
            end)))
        end
    end
    --Generate Terrain End
end

function onReset()
    reset.BorderColor3 = Color3.new(0, 0, 0)
    reset.BackgroundColor3 = Color3.new(0.5, 0.5, 0.5)
    reset.BackgroundTransparency = 0.5
    frame.Visible = false
    toolbarbutton:SetActive(false)
    on = false

    if g:FindFirstChild("rload") == nil then
        rload = Instance.new("Frame", g)
        rload.Name = "rload"
        rload.Position = UDim2.new(0.4, 0, 0.025, 0)
        rload.Size = UDim2.new(0.2, 0, 0.05, 0)
        rload.BackgroundTransparency = 0.5
        rfill = Instance.new("Frame", rload)
        rfill.Name = "rfill"
        rfill.Position = UDim2.new(0, 0, 0, 0)
        rfill.Size = UDim2.new(0, 0, 1, 0)
        rfill.BackgroundColor3 = Color3.new(1, 0.25, 0)
        rfill.BackgroundTransparency = 0.5
    else
        rload = g:FindFirstChild("rload")
        rfill = rload:FindFirstChild("rfill")
        rload.Visible = 1
        rfill.Visible = 1
        rfill.Size = UDim2.new(0, 0, 1, 0)
    end
    --Erase Terrain

    local xMax = c.MaxExtents.Max.X
    local yMax = c.MaxExtents.Max.Y
    local zMax = c.MaxExtents.Max.Z

    local xMin = c.MaxExtents.Min.X
    local yMin = c.MaxExtents.Min.Y
    local zMin = c.MaxExtents.Min.Z


    rprogress = 0

    local waitCount = 0

    z = zMax
    while z >= zMin do
        SetCells(c, Region3int16.new(Vector3int16.new(xMin, yMin, z), Vector3int16.new(xMax, yMax, z)), 0, 0, 0)
        z = z - 1

        rprogress = rprogress + 1/(zMax - zMin + 1)
        rfill.Size = UDim2.new(rprogress, 0, 1, 0)
        if z == zMin then
            reset.BorderColor3 = Color3.new(0, 0, 0)
            rfill.Parent.Visible = false
            rfill.Visible = false
        end
        if waitCount > 5 then waitCount = 0 wait(0.001) else waitCount = waitCount + 1 end
    end

    --Erase Terrain End
end

function On()
    self:Activate(true)
    toolbarbutton:SetActive(true)
    frame.Visible = true
    for w = 0, 0.6, 0.1 do
        frame.Size = UDim2.new(w, 0, w + 0.2, 0)
        wait(0.0000001)
    end
    title.Text = "Terrain Generation"
    xposl.Text = "X-Offset: "..xpos
    zposl.Text = "Z-Offset: "..zpos
    widthl.Text = "Width: "..width
    lengthl.Text = "Length: "..length
    ampl.Text = "Amplitude: "..a
    freql.Text = "Frequency: "..f
    generate.Text = "Generate"
    reset.Text = "Reset"
    on = true

    onGenerate()
end

function Off()
    toolbarbutton:SetActive(false)
    title.Text = ""
    xposl.Text = ""
    zposl.Text = ""
    widthl.Text = ""
    lengthl.Text = ""
    ampl.Text = ""
    freql.Text = ""
    generate.Text = ""
    reset.Text = ""
    for w = 0.6, 0, -0.1 do
        frame.Size = UDim2.new(w, 0, w + 0.2, 0)
        wait(0.0000001)
    end
    frame.Visible = false
    on = false
end




------
--GUI-
------

--load library for with sliders
local RbxGui = LoadLibrary("RbxGui")

--screengui
g = Instance.new("ScreenGui", game:GetService("CoreGui"))

--frame
frame = Instance.new("Frame", g)
frame.Size = UDim2.new(0.6, 0, 0.8, 0)
frame.Position = UDim2.new(0.2, 0, 0.1, 0)
frame.BackgroundTransparency = 0.5
frame.Visible = false

--title
title = Instance.new("TextLabel", frame)
title.Position = UDim2.new(0.4, 0, 0.05, 0)
title.Size = UDim2.new(0.2, 0, 0.05, 0)
title.Text = ""
title.BackgroundColor3 = Color3.new(0.4, 0.4, 0.4)
title.TextColor3 = Color3.new(1, 1, 1)
title.Font = Enum.Font.ArialBold
title.FontSize = Enum.FontSize.Size24
title.BorderColor3 = Color3.new(0, 0, 0)
title.BackgroundTransparency = 1

--current xoffset display label
xposl = Instance.new("TextLabel", frame)
xposl.Position = UDim2.new(0.05, 0, 0.2, 0)
xposl.Size = UDim2.new(0.1, 0, 0.05, 0)
xposl.Text = ""
xposl.BackgroundColor3 = Color3.new(0.4, 0.4, 0.4)
xposl.TextColor3 = Color3.new(1, 1, 1)
xposl.Font = Enum.Font.ArialBold
xposl.FontSize = Enum.FontSize.Size14
xposl.BorderColor3 = Color3.new(0, 0, 0)
xposl.BackgroundTransparency = 1

--xoffset slider
xposSliderGui, xposSliderPosition = RbxGui.CreateSlider(128, 0, UDim2.new(0.2, 0, 0.22, 0))
xposSliderGui.Parent = frame
xposBar = xposSliderGui:FindFirstChild("Bar")
xposBar.Size = UDim2.new(0.75, 0, 0, 5)
xposSliderPosition.Value = (xpos+252)/4 + 1
xposSliderPosition.Changed:connect(function()
    xpos = (xposSliderPosition.Value - 1) * 4 - 252
    xposl.Text = "X-Offset: "..xpos
end)

--current zoffset display label
zposl = Instance.new("TextLabel", frame)
zposl.Position = UDim2.new(0.05, 0, 0.3, 0)
zposl.Size = UDim2.new(0.1, 0, 0.05, 0)
zposl.Text = ""
zposl.BackgroundColor3 = Color3.new(0.4, 0.4, 0.4)
zposl.TextColor3 = Color3.new(1, 1, 1)
zposl.Font = Enum.Font.ArialBold
zposl.FontSize = Enum.FontSize.Size14
zposl.BorderColor3 = Color3.new(0, 0, 0)
zposl.BackgroundTransparency = 1

--zoffset slider
zposSliderGui, zposSliderPosition = RbxGui.CreateSlider(128, 0, UDim2.new(0.2, 0, 0.32, 0))
zposSliderGui.Parent = frame
zposBar = zposSliderGui:FindFirstChild("Bar")
zposBar.Size = UDim2.new(0.75, 0, 0, 5)
zposSliderPosition.Value = (zpos+252)/4 + 1
zposSliderPosition.Changed:connect(function()
    zpos = (zposSliderPosition.Value - 1) * 4 - 252
    zposl.Text = "Z-Offset: "..zpos
end)

--current width display label
widthl = Instance.new("TextLabel", frame)
widthl.Position = UDim2.new(0.05, 0, 0.4, 0)
widthl.Size = UDim2.new(0.1, 0, 0.05, 0)
widthl.Text = ""
widthl.BackgroundColor3 = Color3.new(0.4, 0.4, 0.4)
widthl.TextColor3 = Color3.new(1, 1, 1)
widthl.Font = Enum.Font.ArialBold
widthl.FontSize = Enum.FontSize.Size14
widthl.BorderColor3 = Color3.new(0, 0, 0)
widthl.BackgroundTransparency = 1

--width slider
widthSliderGui, widthSliderPosition = RbxGui.CreateSlider(4, 0, UDim2.new(0.2, 0, 0.42, 0))
widthSliderGui.Parent = frame
widthbar = widthSliderGui:FindFirstChild("Bar")
widthbar.Size = UDim2.new(0.75, 0, 0, 5)
widthSliderPosition.Value = 4
widthSliderPosition.Changed:connect(function()
    width = math.pow(2, widthSliderPosition.Value + 5)
    widthl.Text = "Width: "..width
end)

--current length display label
lengthl = Instance.new("TextLabel", frame)
lengthl.Position = UDim2.new(0.05, 0, 0.5, 0)
lengthl.Size = UDim2.new(0.1, 0, 0.05, 0)
lengthl.Text = ""
lengthl.BackgroundColor3 = Color3.new(0.4, 0.4, 0.4)
lengthl.TextColor3 = Color3.new(1, 1, 1)
lengthl.Font = Enum.Font.ArialBold
lengthl.FontSize = Enum.FontSize.Size14
lengthl.BorderColor3 = Color3.new(0, 0, 0)
lengthl.BackgroundTransparency = 1

--length slider
lengthSliderGui, lengthSliderPosition = RbxGui.CreateSlider(4, 0, UDim2.new(0.2, 0, 0.52, 0))
lengthSliderGui.Parent = frame
lengthbar = lengthSliderGui:FindFirstChild("Bar")
lengthbar.Size = UDim2.new(0.75, 0, 0, 5)
lengthSliderPosition.Value = 4
lengthSliderPosition.Changed:connect(function()
    length = math.pow(2, lengthSliderPosition.Value + 5)
    lengthl.Text = "Length: "..length
end)

--current amplitude display label
ampl = Instance.new("TextLabel", frame)
ampl.Position = UDim2.new(0.05, 0, 0.6, 0)
ampl.Size = UDim2.new(0.1, 0, 0.05, 0)
ampl.Text = ""
ampl.BackgroundColor3 = Color3.new(0.4, 0.4, 0.4)
ampl.TextColor3 = Color3.new(1, 1, 1)
ampl.Font = Enum.Font.ArialBold
ampl.FontSize = Enum.FontSize.Size14
ampl.BorderColor3 = Color3.new(0, 0, 0)
ampl.BackgroundTransparency = 1

--amplitude slider
ampSliderGui, ampSliderPosition = RbxGui.CreateSlider(62, 0, UDim2.new(0.2, 0, 0.62, 0))
ampSliderGui.Parent = frame
ampbar = ampSliderGui:FindFirstChild("Bar")
ampbar.Size = UDim2.new(0.75, 0, 0, 5)
ampSliderPosition.Value = a + 1
ampSliderPosition.Changed:connect(function()
    a = ampSliderPosition.Value + 1
    ampl.Text = "Amplitude: "..a
end)

--current frequency display label
freql = Instance.new("TextLabel", frame)
freql.Position = UDim2.new(0.05, 0, 0.7, 0)
freql.Size = UDim2.new(0.1, 0, 0.05, 0)
freql.Text = ""
freql.BackgroundColor3 = Color3.new(0.4, 0.4, 0.4)
freql.TextColor3 = Color3.new(1, 1, 1)
freql.Font = Enum.Font.ArialBold
freql.FontSize = Enum.FontSize.Size14
freql.BorderColor3 = Color3.new(0, 0, 0)
freql.BackgroundTransparency = 1

--frequency slider
freqSliderGui, freqSliderPosition = RbxGui.CreateSlider(8, 0, UDim2.new(0.2, 0, 0.72, 0))
freqSliderGui.Parent = frame
freqbar = freqSliderGui:FindFirstChild("Bar")
freqbar.Size = UDim2.new(0.75, 0, 0, 5)
freqSliderPosition.Value = 4
freqSliderPosition.Changed:connect(function()
    f = math.pow(2, freqSliderPosition.Value - 1)
    freql.Text = "Frequency: "..f
end)

--generate button
generate = Instance.new("TextButton", frame)
generate.Position = UDim2.new(0.275, 0, 0.85, 0)
generate.Size = UDim2.new(0.2, 0, 0.1, 0)
generate.Text = ""
generate.BackgroundColor3 = Color3.new(0.5, 0.5, 0.5)
generate.TextColor3 = Color3.new(1, 1, 1)
generate.Font = Enum.Font.ArialBold
generate.FontSize = Enum.FontSize.Size14
generate.BorderColor3 = Color3.new(0, 0, 0)
generate.BackgroundTransparency = 0.5
generate.MouseEnter:connect(function()
    generate.BorderColor3 = Color3.new(1, 1, 1)
    generate.BackgroundColor3 = Color3.new(0, 0, 0)
    generate.BackgroundTransparency = 0.2
end)
generate.MouseButton1Click:connect(onGenerate)
generate.MouseLeave:connect(function()
    generate.BorderColor3 = Color3.new(0, 0, 0)
    generate.BackgroundColor3 = Color3.new(0.5, 0.5, 0.5)
    generate.BackgroundTransparency = 0.5
end)

--reset button
reset = Instance.new("TextButton", frame)
reset.Position = UDim2.new(0.525, 0, 0.85, 0)
reset.Size = UDim2.new(0.2, 0, 0.1, 0)
reset.Text = ""
reset.BackgroundColor3 = Color3.new(0.5, 0.5, 0.5)
reset.TextColor3 = Color3.new(1, 1, 1)
reset.Font = Enum.Font.ArialBold
reset.FontSize = Enum.FontSize.Size14
reset.BorderColor3 = Color3.new(0, 0, 0)
reset.BackgroundTransparency = 0.5
reset.MouseEnter:connect(function()
    reset.BorderColor3 = Color3.new(1, 1, 1)
    reset.BackgroundColor3 = Color3.new(0, 0, 0)
    reset.BackgroundTransparency = 0.2
end)
reset.MouseButton1Click:connect(onReset)
reset.MouseLeave:connect(function()
    reset.BorderColor3 = Color3.new(0, 0, 0)
    reset.BackgroundColor3 = Color3.new(0.5, 0.5, 0.5)
    reset.BackgroundTransparency = 0.5
end)




--------------------------
--SUCCESSFUL LOAD MESSAGE-
--------------------------
loaded = true
print("Terrain Plugin Loaded")