50p

local sizeFactor = 10
local me = getLocalPlayer()

local cars = {}     -- { player = { {bone1,bone2} = car, ... }, player = ... }
local prevX, prevY, prevZ
local deg = math.deg
local rad = math.rad
local pi = math.pi
local cos = math.cos
local sin = math.sin
local atan2 = math.atan2
local sqrt = math.sqrt

local screenWidth, screenHeight = guiGetScreenSize()

local phi, theta = 0, 0

local connections = {
    -- spine
    --{ 1, 2 },
    { 2, 3, forward=true },
    --{ 3, 4 },
    { 4, 5 },
    -- right arm
    { 22, 23 },
    { 23, 24 },
    -- left arm
    { 32, 33 },
    { 33, 34 },
    -- right leg
    { 51, 52, forward=true },
    { 52, 53, forward=true },
    -- left leg
    { 41, 42, forward=true },
    { 42, 43, forward=true }
}

function joinHandler(player)
    player = player or source

    cars[player] = {}
    local color = math.random(0, 126)
    for _,connection in ipairs(connections) do
        local vehicle = createVehicle(415, 0, 0, 3)
        setVehicleColor(vehicle, color, color, color, color)
        setVehicleFrozen(vehicle, true)
        setElementCollisionsEnabled(vehicle, false)
        cars[player][connection] = vehicle
    end
    setElementAlpha(player, 0)
    addEventHandler('onClientRender', getRootElement(), onRender)
    addEventHandler('onClientCursorMove', getRootElement(), onMouseMove)
end

addEventHandler('onClientResourceStart', getResourceRootElement(getThisResource()),
    function()
        setTimer(init, 1000, 1)
    end
)

function init()
    for _,player in ipairs(getElementsByType('player')) do
        joinHandler(player)
    end
    setGameSpeed(0.5)
    phi = rad(getPlayerRotation(me) + 90 + 180)
end

addEventHandler('onClientPlayerJoin', getRootElement(), joinHandler)

addEventHandler('onClientPlayerQuit', getRootElement(),
    function()
        if not cars[source] then
            return
        end
        for _,car in pairs(cars[source]) do
            destroyElement(car)
        end
        cars[source] = nil
    end
)

addEventHandler('onClientResourceStop', getResourceRootElement(getThisResource()),
    function()
        for i,player in ipairs(getElementsByType('player')) do
            setElementAlpha(player, 255)
        end
        setCameraTarget(me)
        toggleAllControls(true)
        setGameSpeed(1)
    end
)

local function scale(factor, baseX, baseY, baseZ, x, y, z)
    return baseX + factor*(x-baseX), baseY + factor*(y-baseY), baseZ + factor*(z-baseZ)
end

local function angleDiff(angle1, angle2)
    angle1, angle2 = angle1 % 360, angle2 % 360
    local smallest = math.min(angle1, angle2)
    local largest = math.max(angle1, angle2)
    return math.min(largest - smallest, smallest - (largest - 360))
end

function onRender()
    for player,connections in pairs(cars) do
        -- place cars
        local baseX, baseY, baseZ = getElementPosition(player)
        local playerRZ = getPlayerRotation(player)
        baseZ = baseZ - getElementDistanceFromCentreOfMassToBaseOfModel(player)
        for connection,car in pairs(connections) do
            local x1, y1, z1 = scale(sizeFactor, baseX, baseY, baseZ, getPedBonePosition(player, connection[1]))
            z1 = z1 - 1.3
            local x2, y2, z2 = scale(sizeFactor, baseX, baseY, baseZ, getPedBonePosition(player, connection[2]))
            z2 = z2 - 1.3
            setElementPosition(car, x1 + (x2 - x1)/2, y1 + (y2 - y1)/2, z1 + (z2 - z1)/2)
            local partRX = deg(atan2(z2 - z1, sqrt((x2-x1)*(x2-x1) + (y2-y1)*(y2-y1))))
            local partRZ = deg(atan2(-(x2-x1), y2-y1))
            if connection.forward then
                if angleDiff(partRZ, playerRZ) >= 90 then
                    partRX = partRX - 2*(partRX-270)
                    partRZ = partRZ + 180
                end
                if math.abs((partRX % 360) - 90) < 10 or math.abs((partRX % 360) - 270) < 10 then
                    partRZ = playerRZ
                end
            end
            setElementRotation(car, partRX, 0, partRZ)
        end
    end

    local x, y, z = getElementPosition(me)
    -- move local player faster
    if getPedTask(me, 'primary', 0) ~= 'TASK_SIMPLE_FALL' and prevX then
        x, y = scale(sizeFactor, prevX, prevY, prevZ, x, y, z)
        if isPlayerOnGround(me) then
            local hit, tempX, tempY, tempZ
            hit, tempX, tempY, tempZ = processLineOfSight(x, y, z + 3, x, y, z - 20, true, true, false)
            if hit then
                z = tempZ + getElementDistanceFromCentreOfMassToBaseOfModel(me)
            end
        end
        setElementPosition(me, x, y, z)
    end
    prevX, prevY, prevZ = x, y, z

    -- place camera
    local camX = x + 4*sizeFactor*cos(phi)*cos(theta)
    local camY = y + 4*sizeFactor*sin(phi)*cos(theta)
    local camZ = z + 0.6*sizeFactor + 2*sizeFactor*sin(theta)
    local camLookZ = z + 0.5*sizeFactor
    local hit, hitX, hitY, hitZ = processLineOfSight(x, y, camLookZ, camX, camY, camZ, true, false, false)
    if hit then
        camX, camY, camZ = scale(0.9, x, y, camLookZ, hitX, hitY, hitZ)
    end
    setCameraMatrix(camX, camY, camZ, x, y, camLookZ)
end

function onMouseMove(relX, relY, absX, absY)
    if isMTAWindowActive() then
        return
    end
    absX = absX - screenWidth/2
    absY = absY - screenHeight/2
    phi = (phi - 0.005*absX) % (2*pi)
    theta = theta + 0.005*absY
    if theta > 0.4*pi then
        theta = 0.4*pi
    elseif theta < -0.4*pi then
        theta = -0.4*pi
    end
end