What is VDM (FiveM)? Definition & Prevention

What is VDM?

Vehicle Deathmatch (VDM) refers to the act of using a vehicle as a weapon to intentionally ram, kill, or injure other players without proper roleplay justification. In FiveM roleplay servers, VDM violates fundamental server rules and disrupts the immersive experience players seek.

Why VDM Matters

Roleplay servers operate on the principle of realistic interaction. When a player deliberately rams their vehicle into others without roleplay context, it:

• Breaks immersion for all participants
• Prevents meaningful story development
• Creates unfair gameplay advantages
• Leads to player frustration and server population decline

Common VDM Scenarios

Clear VDM Violations:

• Driving onto sidewalks to hit pedestrians
• Ramming stationary vehicles at traffic lights
• Using vehicles to block hospital entrances
• Intentionally causing head-on collisions

Gray Areas Requiring Context:

• Police pit maneuvers during pursuits
• Gang-related vehicle attacks with prior roleplay
• Accidental collisions during races
• Emergency vehicle responses

Technical Implementation: Anti-VDM Systems

Server-Side Detection Script

-- resources/anti-vdm/server.lua
local vdmWarnings = {}
local VDM_THRESHOLD = 3
local DAMAGE_THRESHOLD = 50

RegisterServerEvent('vdm:checkCollision')
AddEventHandler('vdm:checkCollision', function(targetId, damage, speed)
    local source = source
    
    -- Validate input
    if not targetId or not damage or not speed then return end
    
    -- Check if damage and speed exceed thresholds
    if damage > DAMAGE_THRESHOLD and speed > 30 then
        local identifier = GetPlayerIdentifier(source, 0)
        
        -- Initialize warning count
        if not vdmWarnings[identifier] then
            vdmWarnings[identifier] = 0
        end
        
        vdmWarnings[identifier] = vdmWarnings[identifier] + 1
        
        -- Log incident
        local logData = {
            attacker = GetPlayerName(source),
            victim = GetPlayerName(targetId),
            damage = damage,
            speed = speed,
            timestamp = os.time()
        }
        
        TriggerEvent('vdm:logIncident', logData)
        
        -- Take action based on warnings
        if vdmWarnings[identifier] >= VDM_THRESHOLD then
            DropPlayer(source, 'Kicked for VDM violations')
            vdmWarnings[identifier] = 0
        else
            TriggerClientEvent('chat:addMessage', source, {
                args = {'^1[WARNING]', 'VDM detected. Warning ' .. 
                       vdmWarnings[identifier] .. '/' .. VDM_THRESHOLD}
            })
        end
    end
end)

Client-Side Monitoring

-- resources/anti-vdm/client.lua
local lastCollision = 0
local COLLISION_COOLDOWN = 5000 -- 5 seconds

Citizen.CreateThread(function()
    while true do
        Citizen.Wait(0)
        local playerPed = PlayerPedId()
        
        if IsPedInAnyVehicle(playerPed, false) then
            local vehicle = GetVehiclePedIsIn(playerPed, false)
            
            if GetPedInVehicleSeat(vehicle, -1) == playerPed then
                if HasEntityCollidedWithAnything(vehicle) then
                    local currentTime = GetGameTimer()
                    
                    if currentTime - lastCollision > COLLISION_COOLDOWN then
                        local speed = GetEntitySpeed(vehicle) * 3.6 -- Convert to km/h
                        
                        -- Check for pedestrian collision
                        local coords = GetEntityCoords(vehicle)
                        local closestPed = GetClosestPed(coords.x, coords.y, coords.z, 
                                                         5.0, 1, 0, 0, 0, -1)
                        
                        if DoesEntityExist(closestPed) and IsEntityAPed(closestPed) then
                            local targetPlayer = NetworkGetPlayerIndexFromPed(closestPed)
                            
                            if targetPlayer ~= -1 then
                                local damage = GetEntityHealth(closestPed)
                                TriggerServerEvent('vdm:checkCollision', 
                                                 GetPlayerServerId(targetPlayer), 
                                                 damage, speed)
                            end
                        end
                        
                        lastCollision = currentTime
                    end
                end
            end
        end
    end
end)

Server Configuration

FiveM server.cfg additions:

# Anti-VDM Configuration
set vdm_enabled true
set vdm_max_warnings 3
set vdm_damage_threshold 50
set vdm_speed_threshold 30
set vdm_log_incidents true
set vdm_webhook "https://discord.com/api/webhooks/YOUR_WEBHOOK_HERE"

# Ensure anti-vdm resource starts
ensure anti-vdm

Best Practices for Server Administrators

1. Clear Rule Definition

Create specific VDM rules in your server documentation:

Rule 2.1 - Vehicle Deathmatch (VDM)
- Using any vehicle as a weapon is prohibited
- Exceptions: Authorized police tactics, sanctioned events
- Punishment: 1st offense - Warning, 2nd - 24h ban, 3rd - Permanent ban

2. Staff Training Protocol

Train moderators to identify VDM:

• Review damage logs
• Check player speed at impact
• Verify roleplay context exists
• Document evidence (clips, screenshots)

3. Player Reporting System

-- Simple reporting command
RegisterCommand('reportvdm', function(source, args, rawCommand)
    local targetId = tonumber(args[1])
    local reason = table.concat(args, ' ', 2)
    
    if not targetId or not reason then
        TriggerClientEvent('chat:addMessage', source, {
            args = {'^1[ERROR]', 'Usage: /reportvdm [player_id] [reason]'}
        })
        return
    end
    
    -- Create report ticket
    local report = {
        reporter = GetPlayerName(source),
        reported = GetPlayerName(targetId),
        reason = reason,
        timestamp = os.date('%Y-%m-%d %H:%M:%S'),
        status = 'pending'
    }
    
    -- Store in database or send to Discord
    TriggerEvent('vdm:createReport', report)
end, false)

Common Implementation Challenges

False Positives

• Lag-induced collision detection
• Desync between players
• Legitimate accidents

Solution: Implement grace periods and context checking:

-- Check if players are in active scenario
local function isInActiveRP(playerId)
    -- Check database for active scenarios
    -- Return true if player is in police chase, race, etc.
end

Performance Impact

Monitor script resource usage:

-- Add to fxmanifest.lua
resource_monitor_mode 'yes'

Integration with Popular Frameworks

ESX Framework

ESX = nil
TriggerEvent('esx:getSharedObject', function(obj) ESX = obj end)

-- Add VDM violations to player record
RegisterServerEvent('vdm:recordViolation')
AddEventHandler('vdm:recordViolation', function(targetId)
    local xPlayer = ESX.GetPlayerFromId(source)
    MySQL.Async.execute('INSERT INTO vdm_violations SET identifier = @identifier, timestamp = @timestamp',
    {
        ['@identifier'] = xPlayer.identifier,
        ['@timestamp'] = os.time()
    })
end)

QBCore Framework

local QBCore = exports['qb-core']:GetCoreObject()

-- Integration with admin menu
QBCore.Commands.Add('checkvdm', 'Check player VDM history', {{name = 'id', help = 'Player ID'}}, true, function(source, args)
    local Player = QBCore.Functions.GetPlayer(tonumber(args[1]))
    if Player then
        -- Fetch VDM history
        MySQL.Async.fetchAll('SELECT * FROM vdm_logs WHERE citizenid = @citizenid', {
            ['@citizenid'] = Player.PlayerData.citizenid
        }, function(result)
            TriggerClientEvent('qb-admin:client:showVDMHistory', source, result)
        end)
    end
end, 'admin')

Testing Your Anti-VDM System

Automated Test Suite

-- tests/vdm_test.lua
local function testVDMDetection()
    -- Simulate collision event
    local mockData = {
        attacker = 1,
        victim = 2,
        damage = 75,
        speed = 45
    }
    
    TriggerEvent('vdm:checkCollision', mockData.victim, mockData.damage, mockData.speed)
    
    -- Verify warning was issued
    -- Check if log was created
    -- Confirm webhook was triggered
end

Performance Metrics

Track system effectiveness:

-- Database schema
CREATE TABLE vdm_metrics (
    id INT AUTO_INCREMENT PRIMARY KEY,
    date DATE,
    total_incidents INT,
    warnings_issued INT,
    players_kicked INT,
    false_positives INT
);

Conclusion

VDM prevention requires technical implementation, clear rules, and consistent enforcement to maintain quality roleplay environments in FiveM servers.