A Catastrophes plugin for cuberite minecraft server

NaturesRevenge.lua

--[=====[
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allowed_distance=4*16*2 --4 chunks in both directions
block_count=50
block_depth=3

delay=100
next_process=80
elapsed=0

function make_set(t)
    local ret={}
    for i,v in ipairs(t) do
        ret[v]=true
    end
    return ret
end
allowed_blocks=make_set{
    E_BLOCK_LOG,
    E_BLOCK_LEAVES,
    E_BLOCK_NEW_LEAVES,     
    E_BLOCK_NEW_LOG,
    E_BLOCK_GRASS,
    E_BLOCK_TALL_GRASS,
    E_BLOCK_DEAD_BUSH
}
function make_top( w,x,y,z,btype,bmeta )
    for i=-1,1 do
    for j=-1,1 do
        w:SetBlock(x+i,y,z+j,btype,bmeta)
    end
    end
end
function make_shoot( w,x,y,z,btype,bmeta,steps_max ,angle_step_max)
    local angle_step=0.15+math.random()*(angle_step_max or 0)
    local dist=1

    local steps=math.random(1,steps_max)

    local theta=math.random()*math.pi
    local phi=math.random()*math.pi*2

    local cx=x
    local cy=y
    local cz=z
    for i=1,steps do
        w:SetBlock(cx,cy,cz,btype,bmeta)
        theta=theta+math.random()*angle_step/2-angle_step/2
        phi=phi+math.random()*angle_step/2-angle_step/2
        cx=cx+math.sin(theta)*math.cos(phi)*dist
        cz=cz+math.sin(theta)*math.sin(phi)*dist
        cy=cy+math.cos(theta)*dist
    end
end
function block_action(w,x,y,z,btype,bmeta)--todo: rewrite to use block area
    local new_type=btype
    if btype==E_BLOCK_LOG then
        new_type=E_BLOCK_LEAVES
    elseif btype==E_BLOCK_NEW_LOG then 
        new_type=E_BLOCK_NEW_LEAVES
    elseif btype==E_BLOCK_LEAVES then
        new_type=E_BLOCK_LOG
    elseif btype==E_BLOCK_NEW_LEAVES then
        new_type=E_BLOCK_NEW_LOG
    else
        new_type=E_BLOCK_NEW_LOG
    end
    
    local r=math.random()
    if r>0.85 then
        make_top(w,x,y+1,z,new_type,bmeta)
    elseif r>0.75 then
        make_shoot(w,x,y,z,new_type,bmeta,15,math.random()*0.75)
    elseif r>0.5 then
        make_shoot(w,x,y,z,new_type,bmeta,15,math.random()*0.15)
    else
        w:SetBlock(x,y+1,z,new_type,bmeta)
    end
end
function real_process(world,center)
    return function ()
    local a2=allowed_distance/2
        for i=1,block_count do
            local x=center.x+math.random(-a2,a2)
            local z=center.z+math.random(-a2,a2)
            local ok,h=world:TryGetHeight(x,z)

            if h>=253 then ok=false end
            --local h=center.y+math.random(-block_depth*2,block_depth*2)
            
            if ok then
                for i=0,-block_depth,-1 do
                    local valid,btype,bmeta=world:GetBlockTypeMeta(x,h+i,z)
                    if valid and allowed_blocks[btype] then
                        
                        block_action(world,x,h+i,z,btype,bmeta)
                        break
                    end
                end
            end
        
        end
    end
end
function do_process(player)
    local w=player:GetWorld()
    local center=player:GetPosition()
    w:QueueTask(real_process(w,center))
    
end
function every_tick(time_delta)
    elapsed=elapsed+time_delta
    if elapsed>next_process then
        next_process=math.random(delay/2,delay*2)
        elapsed=0
        cRoot:Get():ForEachPlayer(do_process)
        --cRoot:Get():ForEachPlayer(hang)
    end
    
end
function Initialize(a_Plugin)
    a_Plugin:SetName("NaturesRevenge");
    a_Plugin:SetVersion(1);
    
    cPluginManager:AddHook(cPluginManager.HOOK_TICK, every_tick);
    
    return true;
end