half the island range, add island border view

nc_sky_isgen/init.lua

@@ -158,8 +158,65 @@ end
 local air_c = minetest.get_content_id("air")
 local ignore_c = minetest.get_content_id("ignore")
 
+local function spawn_particle(x,y,z,player)
+  minetest.add_particlespawner{
+        amount = 30,
+        -- Number of particles spawned over the time period `time`.
+
+        time = 60,
+
+        minpos = {x=x, y=y, z=z},
+        maxpos = {x=x, y=y, z=z},
+        minvel = {x=-0.5, y=-0.5, z=-0.5},
+        maxvel = {x=0.5, y=0.5, z=0.5},
+        minacc = {x=0, y=0, z=0},
+        maxacc = {x=0, y=0, z=0},
+        minexptime = 2,
+        maxexptime = 3,
+        minsize = 5,
+        maxsize = 10,
+        vertical = false,
+        texture = "nc_lux_gravel.png",
+        playername = player,
+
+        glow = 14
+    }
+end
 local function island_range(x,y,z)
-  return {x=x-64,y=y-64,z=z-64},{x=x+64,y=y+64,z=z+64}
+  return {x=x-32,y=y-32,z=z-32},{x=x+32,y=y+32,z=z+32}
+end
+local function spawn_particles(x,y,z,player)
+  local mi,ma = island_range(x,y,z)
+  local visited = {}
+  for n1=0,1 do
+    for n2=0,1 do
+      for _,ord1 in ipairs({"x","y","z"}) do
+        for _,ord2 in ipairs({"x","y","z"}) do
+          for _,ord3 in ipairs({"x","y","z"}) do
+            if ord2 ~= ord1 and ord3 ~= ord2 and ord3 ~= ord1 then
+              for x=mi[ord1],ma[ord1] do
+                local pos = {[ord1]=x}
+                if n1 == 0 then
+                  pos[ord2] = mi[ord2]
+                else
+                  pos[ord2] = ma[ord2]
+                end
+                if n2 == 0 then
+                  pos[ord3] = mi[ord3]
+                else
+                  pos[ord3] = ma[ord3]
+                end
+                --print(dump(pos))
+                if math.random(10)==1 then
+                  spawn_particle(pos.x,pos.y,pos.z,player)
+                end
+              end
+            end
+          end
+        end
+      end
+    end
+  end
 end
 local function checkpos(x,y,z)
   local vm = VoxelManip(island_range(x,y,z))
@@ -427,6 +484,8 @@ minetest.register_chatcommand("query", {
       minetest.chat_send_player(name,"  takeable: "..tostring(is.valid))
       minetest.chat_send_player(name,"  pos: "..minetest.pos_to_string(is.pos))
       minetest.chat_send_player(name,"]")
+      local p = is.pos
+      spawn_particles(p.x,p.y,p.z,name)
     else
       minetest.chat_send_player(name,S"No island here")
     end