nocturnalzombies

--[[
Zombies become very active at night, scattering and moving around often

TwoHoursOfTerrorUse: from midnight to 2am zombies gain a speed boost

By Nolan Ritchie

Modified by cerastes

Changed the roaming algorithm:
1) A random number ("target"), a random increment, and a random location to roam to are picked for each zombie.
2) During every iteration of the roaming function, each zombie's target is reduced by the increment.
3) If the target reaches zero, steps 1 is repeated and the cycle restarts.

This approach makes zombie roaming look more random - zombies do not all change direction at the same time.

Finally, there's a "pullback" function. This roaming algorithm's downside is that the zombies might be directed
to leave the player's cell. Once they leave, they can't be recalled easily. This means that this algorithm
may actually push zombies away from the player, which is pretty much the exact opposite of the intended effect.
So, a pullback function is needed to force the zombies to come towards the player if they get too close to the cell's edge.

]]

local interval = 400;
local PUCount = 0;
local TwoHoursOfTerrorUse = false;
local tempx;
local tempy;
local diffX;
local diffY;
local playerX;
local playerY;
local playerZ;
local distanceFromPlayer;
local target;

function updateZombie( currentZombie )
    tempx = currentZombie:getX() + ZombRand(-100.0,100.0);
    tempy = currentZombie:getY() + ZombRand(-100.0,100.0);
    currentZombie:pathToLocation(tempx,tempy,currentZombie:getZ());
    currentZombie:getModData().increment = ZombRand(100, 400);
    currentZombie:getModData().target = ZombRand(interval, interval * 3 );
    currentZombie:getModData().doNotDisturb = false;
end


function ScatterZombies()
    local hour = getGameTime():getTimeOfDay();
    if( hour < 5.0 ) or ( hour >= 22.0) then
        if(TwoHoursOfTerrorUse) then sendClientCommand(getPlayer(), "NocturnalZombies", "ScatterZombies", {TwoHoursOfTerror= "true"});
        else  sendClientCommand(getPlayer(), "NocturnalZombies", "ScatterZombies", {TwoHoursOfTerror= "false"}) end

        local zlist = getPlayer():getCell():getZombieList();

        if(zlist ~= nil) then

            playerX = getPlayer():getX();
            playerY = getPlayer():getY();
            playerZ = getPlayer():getZ();

            --debug - see how many zombies are nearby
            --print( zlist:size() );

            for i=0, zlist:size()-1 do

                local currentZombie = zlist:get(i);

                if(currentZombie:getModData() ~= nil) then
                    if( currentZombie:getModData().target ~= nil ) and ( currentZombie:getModData().doNotDisturb == false ) then

                        target = currentZombie:getModData().target;
                        target = target - currentZombie:getModData().increment;

                        if( target <= 0 ) then
                            --- calculate new position and send the zombie there
                            updateZombie(currentZombie);
                        else
                            currentZombie:getModData().target = target;
                        end

                    else
                        updateZombie(currentZombie);
                    end
                else
                    updateZombie(currentZombie);
                end

                -- calculate the current zombie's distance from the player
                diffX = playerX - currentZombie:getX();
                diffY = playerY - currentZombie:getY();
                distanceFromPlayer = math.sqrt( ( diffX * diffX ) + ( diffY * diffY ) );
                --print( distanceFromPlayer );

                -- pullback (see description above)
                if( distanceFromPlayer > 90 ) then
                    currentZombie:pathToLocation( playerX, playerY, playerZ );
                    currentZombie:getModData().doNotDisturb = true;
                    currentZombie:getModData().increment = interval;
                    currentZombie:getModData().target = interval * 2;
                else
                -- reset the do not disturb flag so that the zombie can path normally
                    currentZombie:getModData().doNotDisturb = false;
                end

            end
        end
    end
end


function NZInit()
    PUCount = 0;
    if (TwoHoursOfTerror ~= nil) then
        TwoHoursOfTerrorUse = TwoHoursOfTerror;
    else
        TwoHoursOfTerrorUse = false;
    end
end

function NZPlayerUpdateHandle(player)
PUCount = PUCount + 1;
    --player:Say(tostring(TwoHoursOfTerrorUse))
    if(PUCount == interval) then
        --player:Say("working");
        ScatterZombies();
        PUCount = 0;
    end

end

Events.OnGameStart.Add(NZInit);
Events.OnPlayerUpdate.Add(NZPlayerUpdateHandle);