[Sparke]

I recommend using Prox Detector;

Create a Prox Detector stock some where near the top of your script

pawn Код:

stock ProxDetector(Float:radi, playerid, string[],color)
{
    new Float:x,Float:y,Float:z;
    GetPlayerPos(playerid,x,y,z);
    foreach(Player,i)
    {
        if(IsPlayerInRangeOfPoint(i,radi,x,y,z))
        {
            SendClientMessage(i,color,string);
        }
    }
}

Then add on your OnPlayerText callback

pawn Код:

public OnPlayerText(playerid, text[])
{
    new
        message[128];
    format(message, sizeof(message), "%s says: %s", GetName(playerid), text);
    ProxDetector(30.0, playerid, message, -1);
    return 0;
}

For a in depth tutorial just look in tuts