액티브 래그돌 시스템 아키텍처: Motor6D 분리, 비례-미분(PD) 균형 제어 및 피격 회복

--!strict
local RunService = game:GetService("RunService")
local Players = game:GetService("Players")

export type ActiveJoint = {
    Motor: Motor6D,
    Socket: BallSocketConstraint,
    AlignOrientation: AlignOrientation,
    Attachment0: Attachment,
    Attachment1: Attachment,
    StiffnessKp: number,
    DampingKd: number,
}

local ActiveRagdoll = {}
ActiveRagdoll.__index = ActiveRagdoll

function ActiveRagdoll.new(character: Model)
    local self = setmetatable({}, ActiveRagdoll)
    self.Character = character
    self.Humanoid = character:WaitForChild("Humanoid") :: Humanoid
    self.RootPart = character:WaitForChild("HumanoidRootPart") :: BasePart
    self.Joints = {} :: {ActiveJoint}
    self.IsActive = false
    self.BalanceRecoveryTime = 0

    self:SetupJoints()
    return self
end

function ActiveRagdoll:SetupJoints()
    for _, desc in ipairs(self.Character:GetDescendants()) do
        if desc:IsA("Motor6D") and desc.Name ~= "RootJoint" then
            local part0 = desc.Part0
            local part1 = desc.Part1
            if part0 and part1 then
                local att0 = Instance.new("Attachment")
                att0.CFrame = desc.C0
                att0.Parent = part0

                local att1 = Instance.new("Attachment")
                att1.CFrame = desc.C1
                att1.Parent = part1

                local socket = Instance.new("BallSocketConstraint")
                socket.Attachment0 = att0
                socket.Attachment1 = att1
                socket.LimitsEnabled = true
                socket.TwistLimitsEnabled = true
                socket.UpperAngle = 60
                socket.TwistLowerAngle = -45
                socket.TwistUpperAngle = 45
                socket.Enabled = false
                socket.Parent = part1

                local align = Instance.new("AlignOrientation")
                align.Mode = Enum.OrientationAlignmentMode.TwoAttachment
                align.Attachment0 = att1
                align.Attachment1 = att0
                align.MaxTorque = 8000
                align.Responsiveness = 40
                align.Enabled = false
                align.Parent = part1

                table.insert(self.Joints, {
                    Motor = desc,
                    Socket = socket,
                    AlignOrientation = align,
                    Attachment0 = att0,
                    Attachment1 = att1,
                    StiffnessKp = 8000,
                    DampingKd = 40,
                })
            end
        end
    end
end

function ActiveRagdoll:Enable()
    self.IsActive = true
    self.Humanoid.PlatformStand = true

    for _, joint in ipairs(self.Joints) do
        joint.Motor.Enabled = false
        joint.Socket.Enabled = true
        joint.AlignOrientation.Enabled = true
    end
end

function ActiveRagdoll:Disable()
    self.IsActive = false
    self.Humanoid.PlatformStand = false

    for _, joint in ipairs(self.Joints) do
        joint.AlignOrientation.Enabled = false
        joint.Socket.Enabled = false
        joint.Motor.Enabled = true
    end
end

function ActiveRagdoll:ApplyImpulse(hitPart: BasePart, impulse: Vector3)
    hitPart:ApplyImpulse(impulse)
    -- 피격 시 일시적으로 관절 힘을 빼서 리얼한 피격감 연출
    for _, joint in ipairs(self.Joints) do
        if joint.Motor.Part1 == hitPart then
            joint.AlignOrientation.MaxTorque = joint.StiffnessKp * 0.15
            task.delay(0.35, function()
                joint.AlignOrientation.MaxTorque = joint.StiffnessKp
            end)
        end
    end
end

return ActiveRagdoll