rocks/veins.lua

   1 -- experimental fast vein generator
   2
   3 rocks.veins={}
   4
   5 table.insert(rocks.veins,{
   6  scarcity=80,
   7
   8 })
   9
  10
  11 rocksl.genvein=function(minp,maxp,pr,vm,area)
  12  local t1 = os.clock()
  13  local data = vm:get_data()
  14
  15  local chunksizer = maxp.x - minp.x + 1
  16  local chunksize = chunksizer + 1
  17  local pmapsize = {x = chunksize, y = chunksize, z = chunksize}
  18  local minpxz = {x = minp.x, y = minp.z}
  19  local c_sample=minetest.get_content_id("default:stone")
  20  local c_sample_ore=minetest.get_content_id("default:mese")
  21
  22
  23   local A=vector.new(pr:next(0,chunksizer)+minp.x,pr:next(0,chunksizer)+minp.y,pr:next(0,chunksizer)+minp.z)
  24   local B=vector.new(pr:next(0,chunksizer)+minp.x,pr:next(0,chunksizer)+minp.y,pr:next(0,chunksizer)+minp.z)
  25   local C=vector.new(pr:next(0,chunksizer)+minp.x,pr:next(0,chunksizer)+minp.y,pr:next(0,chunksizer)+minp.z)
  26   local D=vector.new(pr:next(0,chunksizer)+minp.x,pr:next(0,chunksizer)+minp.y,pr:next(0,chunksizer)+minp.z)
  27   local l1=vector.distance(A,C)+vector.distance(C,B)
  28   local l2=vector.distance(A,D)+vector.distance(D,B)
  29   local step=1.4/math.max(l1,l2)
  30   print("step="..step.." l1="..l1.." l2="..l2)
  31   local scarcity=6
  32   local ocn=pr:next(0,scarcity)+(scarcity/2)
  33   for t=0, 1, step do
  34    local P=vector.multiply(A,(1-t)^2)
  35    P=vector.add(P, vector.multiply(B,t*t) )
  36    local Q=vector.add(P, vector.multiply(D,2*t*(1-t)) )
  37    P=vector.add(P, vector.multiply(C,2*t*(1-t)) )
  38    local step2=1/vector.distance(P,Q)
  39    for u=0, 1, step2 do
  40     local R=vector.add(vector.multiply(P,(1-u)), vector.multiply(Q,u) )
  41     local di=area:indexp(vector.round(R))
  42     if ocn<1 then
  43      data[di]=c_sample_ore
  44      ocn=pr:next(0,scarcity)+(scarcity/2)
  45     else
  46      data[di]=c_sample
  47      ocn=ocn-1
  48     end
  49    end
  50   end
  51
  52  vm:set_data(data)
  53  minetest.log("action", "rocks/genvein/ "..math.ceil((os.clock() - t1) * 1000).." ms ")
  54 end