From 7574b0f463fcfd2fa41412ef9faed63b0f0aeab7 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Tom=C3=A1=C5=A1=20Brada?= <tomasbrod@azet.sk>
Date: Sun, 10 May 2015 12:42:29 +0200
Subject: [PATCH] Multiple sedimentary layers.

---
 rocks/gensed.lua | 127 +++++++++++++++++++++++++++--------------------
 1 file changed, 72 insertions(+), 55 deletions(-)

diff --git a/rocks/gensed.lua b/rocks/gensed.lua
index e3f6f9c..72c3954 100644
--- a/rocks/gensed.lua
+++ b/rocks/gensed.lua
@@ -1,5 +1,11 @@
 -- experimental sedimentary layer generator
 
+local np_elv = {
+ offset = 0, octaves = 2, persist = 0.4,
+ scale = 8,
+ spread = {x=25, y=25, z=25},
+ seed = -546,
+}
 local np_typ1 = {
  offset = 0, octaves = 2, persist = 0.33,
  scale = 1,
@@ -36,20 +42,23 @@ rocksl.gensed = function (minp, maxp, seed)
 
  local chunksize = maxp.x - minp.x + 1
  local pmapsize = {x = chunksize, y = chunksize, z = chunksize}
- local pmapminpxz = {x = minp.x, y = minp.z}
- local c_stone= minetest.get_content_id("rocks:mudstone")
+ local minpxz = {x = minp.x, y = minp.z}
+ local c_stone= minetest.get_content_id("default:stone")
  local c_dwg= c_stone
- --DEBUG: c_dwg= minetest.get_content_id("default:dirt_with_grass")
 
- local n_tp1
- local n_tp2
- local n_vc
- local n_sp
-
- local layers = {
+ local sla = {
+  {min=18, sd=169},
+  {min=9, sd=324},
+  {min=0, sd=-230},
+  {min=-6, sd=850},
+  {min=-12, sd=-643},
+  {min=-18, sd=0},
+ }
+ if minp.y<(sla[#sla].min-10) then return end
+ local biomes = {
   lava={ mod="default" },
-  stone={ mod="default" },
-  dirt={ mod="default" },
+  nyancat={ mod="default" },
+  wood={ mod="default" },
   gravel={ mod="default" },
   sand={ mod="default" },
   sandstone={ mod="default" },
@@ -63,85 +72,93 @@ rocksl.gensed = function (minp, maxp, seed)
   lignite={ mod="rocks" },
   anthracite={ mod="rocks" },
  }
- for k,v in pairs(layers) do
+ for k,v in pairs(biomes) do
   v.ctx=v.ctx or minetest.get_content_id(v.mod..":"..k)
   if stats and (stats[k]==nil) then stats[k]=0 end
  end
+ n_elv= minetest.get_perlin_map(np_elv, pmapsize) : get2dMap_flat(minp)
  
- local nixz= 1
+ local generated
+ local nixz= 0
+ local nixyz= 0
  for z=minp.z, maxp.z do for x=minp.x, maxp.x do
+  nixz= nixz+1
   -- loop
+  local bi
   local li
-  local generated
-
-  for y=minp.y, maxp.y do
+  for y=maxp.y, minp.y, -1 do
+   nixyz=nixyz+1
    local di=area:index(x,y,z)
-   if ((data[di]==c_stone)or(data[di]==c_dwg)) and (not generated) then
-    generated=true
-    if not n_tp1 then
-     n_tp1= minetest.get_perlin_map(np_typ1, pmapsize) : get2dMap_flat(pmapminpxz)
-     n_tp2= minetest.get_perlin_map(np_typ2, pmapsize) : get2dMap_flat(pmapminpxz)
-     n_vc= minetest.get_perlin_map(np_vc, pmapsize) : get2dMap_flat(pmapminpxz)
-     n_sp= minetest.get_perlin_map(np_sp, pmapsize) : get2dMap_flat(pmapminpxz)
+   local yn=y +n_elv[nixz]
+   if (data[di]==c_stone) and ((not bi)or(yn<sla[li].min)) then
+    -- go to deeper layer
+    if not li then li=1 end
+    while (li<=#sla)and(sla[li].min>yn) do
+     li=li+1
+    end
+    -- create noises for this layer
+    if li>#sla then break end -- break y loop if too low
+    if (not sla[li].n_tp1) then
+     local altminpxz={ x=minp.x+sla[li].sd,
+                          y=minp.z-sla[li].sd}
+     sla[li].n_tp1= minetest.get_perlin_map(np_typ1, pmapsize) : get2dMap_flat(altminpxz)
+     sla[li].n_tp2= minetest.get_perlin_map(np_typ2, pmapsize) : get2dMap_flat(altminpxz)
+     sla[li].n_vc= minetest.get_perlin_map(np_vc, pmapsize) : get2dMap_flat(altminpxz)
+     sla[li].n_sp= minetest.get_perlin_map(np_sp, pmapsize) : get2dMap_flat(altminpxz)
     end
-
   -- BEGIN geome resolution
-  
-  local vcva= math.abs(n_vc[nixz])
-  local vcv= n_vc[nixz]
-  local spv= n_sp[nixz]
+  local vcva= math.abs(sla[li].n_vc[nixz])
+  local vcv= sla[li].n_vc[nixz]
+  local spv= sla[li].n_sp[nixz]
   local tp=1 --=particulates, 2=biosediments, 3=chemosediments, 4=vulcanosediments
-  if n_tp1[nixz]>0.2 then tp=2
-   if n_tp2[nixz]>0.81 then tp=4 end
-  elseif n_tp2[nixz]>0.76 then tp=3 end
+  if sla[li].n_tp1[nixz]>0.2 then tp=2
+   if sla[li].n_tp2[nixz]>0.81 then tp=4 end
+  elseif sla[li].n_tp2[nixz]>0.76 then tp=3 end
 
   if tp==1 then
    -- particulates
    if vcva>0.453 then
     -- clay-(0,stone,slate)
-    if spv>0.23 then li="slate"
-    elseif spv>-0.2 then li="claystone"
-    else li="clay" end
+    if spv>0.23 then bi="slate"
+    elseif spv>-0.2 then bi="claystone"
+    else bi="clay" end
    elseif vcva>0.4 then
-    li="mudstone"
+    bi="mudstone"
    elseif vcva>0.2 then
     -- sand-(0,stone)
-    if spv>-0.3 then li="sandstone" else li="sand" end
+    if spv>-0.3 then bi="sandstone" else bi="sand" end
    else
     -- gravel/conglomerate
-    if spv>-0.34 then li="conglomerate" else li="gravel" end
+    if spv>-0.34 then bi="conglomerate" else bi="gravel" end
     -- breccia?
    end
   elseif tp==2 then
    -- biosediments
-   if vcv>0.72 then
-    --ropa
-    li="lava"
-   elseif vcv>-0.24 then
-    li="limestone"
-   elseif vcv>-0.44 then
-    --ine
-    li="stone"
-   else
+   if vcv>0.05 then
+    bi="limestone"
+   elseif vcv>-0.1 then
     --uhlia
-    if spv>0.7 then li="anthracite"
-    elseif spv>0 then li="blackcoal"
-    else li="lignite" end
+    if spv>0.7 then bi="anthracite"
+    elseif spv>0 then bi="blackcoal"
+    else bi="lignite" end
+   else
+    --ine
+    bi="wood"
    end
   end
-  if not li then li="dirt" end
 
   -- END geome resolution
 
+    if not bi then bi="nyancat" end
+    generated=true
    end
-   if ((data[di]==c_stone)or(data[di]==c_dwg)) and li then
-    data[di]=layers[li].ctx
-    if stats then stats.total=stats.total+1 stats[li]=stats[li]+1 end
+   if (data[di]==c_stone) then
+    data[di]=biomes[bi].ctx
+    if stats then stats.total=stats.total+1 stats[bi]=stats[bi]+1 end
    end
   end
-  nixz= nixz+1
  end end
- if n_tp1 then
+ if generated then
   vm:set_data(data)
   vm:write_to_map(data)
   if stats then for k,v in pairs(stats) do  print("stat: "..k..": "..((v/stats.total)*100).."%") end end