FS Speed Limit

//Speedlimit created by VanGans
#include <a_samp>
#include <sscanf>
#define COLOR_WHITE 0xFFFFFFAA
#define COLOR_GREY 0xAFAFAFAA
#define COLOR_LIGHTBLUE 0x33CCFFAA`
// Speedlimit
new Speedlimit[MAX_PLAYERS];
#define SpeedCheck(%0,%1,%2,%3,%4) floatround(floatsqroot(%4?(%0*%0+%1*%1+%2*%2):(%0*%0+%1*%1) ) *%3*1.6)


public OnFilterScriptInit()
{
    return 1;
}

public OnFilterScriptExit()
{
    return 1;
}

public OnGameModeInit()
{

    return 1;
}

public OnGameModeExit()
{
    return 1;
}

public OnPlayerRequestClass(playerid, classid)
{
    return 1;
}

public OnPlayerConnect(playerid)
{
    Speedlimit[playerid] = 0;
    return 1;
}

public OnPlayerDisconnect(playerid, reason)
{
    return 1;
}

public OnPlayerSpawn(playerid)
{
    return 1;
}

public OnPlayerDeath(playerid, killerid, reason)
{
    return 1;
}

public OnVehicleSpawn(vehicleid)
{
    return 1;
}

public OnVehicleDeath(vehicleid, killerid)
{
    return 1;
}

public OnPlayerText(playerid, text[])
{
    return 1;
}

public OnPlayerCommandText(playerid, cmdtext[])
{
if (strcmp("/speedlimit", cmdtext, true, 10) == 0)
    {
    new string[128], speed;
    if(sscanf(cmdtext, "i", speed)) return SendClientMessage(playerid, COLOR_WHITE, "USAGE: /speedlimit [Max MPH]");
    if(speed < 0) return SendClientMessage(playerid, COLOR_GREY, "Invalid MPH speed.");
    Speedlimit[playerid] = speed;
    if(speed == 0) format(string, sizeof(string), " You have turned your speed limit off.", speed);
    else format(string, sizeof(string), " You have set your speed limit to %d MPH, any vehicle you drive will not go past this limit.", speed);
    SendClientMessage(playerid, COLOR_GREY, string);
    }
return 1;
}
public OnPlayerEnterVehicle(playerid, vehicleid, ispassenger)
{
    return 1;
}

public OnPlayerExitVehicle(playerid, vehicleid)
{
    return 1;
}

public OnPlayerStateChange(playerid, newstate, oldstate)
{
    return 1;
}

public OnPlayerEnterCheckpoint(playerid)
{
    return 1;
}

public OnPlayerLeaveCheckpoint(playerid)
{
    return 1;
}

public OnPlayerEnterRaceCheckpoint(playerid)
{
    return 1;
}

public OnPlayerLeaveRaceCheckpoint(playerid)
{
    return 1;
}

public OnRconCommand(cmd[])
{
    return 1;
}

public OnPlayerRequestSpawn(playerid)
{
    return 1;
}

public OnObjectMoved(objectid)
{
    return 1;
}

public OnPlayerObjectMoved(playerid, objectid)
{
    return 1;
}

public OnPlayerPickUpPickup(playerid, pickupid)
{
    return 1;
}

public OnVehicleMod(playerid, vehicleid, componentid)
{
    return 1;
}

public OnVehiclePaintjob(playerid, vehicleid, paintjobid)
{
    return 1;
}

public OnVehicleRespray(playerid, vehicleid, color1, color2)
{
    return 1;
}

public OnPlayerSelectedMenuRow(playerid, row)
{
    return 1;
}

public OnPlayerExitedMenu(playerid)
{
    return 1;
}

public OnPlayerInteriorChange(playerid, newinteriorid, oldinteriorid)
{
    return 1;
}

public OnPlayerKeyStateChange(playerid, newkeys, oldkeys)
{
    return 1;
}

public OnRconLoginAttempt(ip[], password[], success)
{
    return 1;
}

public OnPlayerUpdate(playerid)
{
 // Speedlimit
        if(GetPlayerState(playerid) == PLAYER_STATE_DRIVER && Speedlimit[playerid])
        {
            new a, b, c;
            GetPlayerKeys(playerid, a, b ,c);
            if(a == 8 && GetVehicleSpeed(GetPlayerVehicleID(playerid), 0) > Speedlimit[playerid])
            {
                new newspeed = GetVehicleSpeed(GetPlayerVehicleID(playerid), 0) - Speedlimit[playerid];
                ModifyVehicleSpeed(GetPlayerVehicleID(playerid), -newspeed);
            }
        }
        return 1;
}

public OnPlayerStreamIn(playerid, forplayerid)
{
    return 1;
}

public OnPlayerStreamOut(playerid, forplayerid)
{
    return 1;
}

public OnVehicleStreamIn(vehicleid, forplayerid)
{
    return 1;
}

public OnVehicleStreamOut(vehicleid, forplayerid)
{
    return 1;
}

public OnDialogResponse(playerid, dialogid, response, listitem, inputtext[])
{
    return 1;
}

public OnPlayerClickPlayer(playerid, clickedplayerid, source)
{
    return 1;
}
stock GetVehicleSpeed(vehicleid, get3d)
{
    new Float:x, Float:y, Float:z;
    GetVehicleVelocity(vehicleid, x, y, z);
    return SpeedCheck(x, y, z, 100.0, get3d);
}
stock ModifyVehicleSpeed(vehicleid,mph) //Miles Per Hour
{
    new Float:Vx,Float:Vy,Float:Vz,Float:DV,Float:multiple;
    GetVehicleVelocity(vehicleid,Vx,Vy,Vz);
    DV = floatsqroot(Vx*Vx + Vy*Vy + Vz*Vz);
    if(DV > 0) //Directional velocity must be greater than 0 (display strobes if 0)
    {
        multiple = ((mph + DV * 100) / (DV * 100)); //Multiplying DV by 100 calculates speed in MPH
        return SetVehicleVelocity(vehicleid,Vx*multiple,Vy*multiple,Vz*multiple);
    }
    return 0;
}