diff --git a/pkg/iceball/radtest/client_start.lua b/pkg/iceball/radtest/client_start.lua
new file mode 100644
index 0000000..f7d96b4
--- /dev/null
+++ b/pkg/iceball/radtest/client_start.lua
@@ -0,0 +1,202 @@
+--[[
+    This file is part of Ice Lua Components.
+
+    Ice Lua Components is free software: you can redistribute it and/or modify
+    it under the terms of the GNU Lesser General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    Ice Lua Components is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU Lesser General Public License for more details.
+
+    You should have received a copy of the GNU Lesser General Public License
+    along with Ice Lua Components.  If not, see <http://www.gnu.org/licenses/>.
+]]
+
+-- Example mod. NOT RELIABLE.
+
+loadfile("pkg/base/client_start.lua")(...)
+
+do
+	local xlen,ylen,zlen
+	local x,y,z,i,j,ci
+	
+	xlen,ylen,zlen = common.map_get_dims()
+	
+	-- get top height map
+	print("Calculating top height map")
+	local hm = {}
+	for z=0,zlen-1 do
+		hm[z] = {}
+		for x=0,xlen-1 do
+			local l = common.map_pillar_get(x,z)
+			hm[z][x] = l[1+1]
+		end
+	end
+	
+	-- build pillar table
+	print("Building pillar run table")
+	local pm = {}
+	for z=0,zlen-1 do
+		pm[z] = {}
+		for x=0,xlen-1 do
+			local pma = {}
+			local l = common.map_pillar_get(x,z)
+			i = 1
+			while true do
+				pma[#pma+1] = l[i+3]
+				pma[#pma+1] = l[i+1]
+				if l[i+0] == 0 then
+					break
+				end
+				i = i + 4*l[i+0]
+			end
+			pma[1] = 0
+			pm[z][x] = pma
+		end
+	end
+	
+	-- some functions for density calculation
+	local function calcdens_pillar(x,z,y1,y2)
+		local pma = pm[z%zlen][x%xlen]
+		local y,i
+		local d = 0
+		for i=1,#pma,2 do
+			local h1 = pma[i+0]
+			local h2 = pma[i+1]
+			if h1 > y2 then break end
+			if h2 > y1 then
+				for y=y1,y2 do
+					if y >= h1 and y <= h2 then
+						d = d + 1
+					end
+				end
+			end
+		end
+		return d/(y2-y1+1)
+	end
+	
+	function calcdens(x1,y1,z1,x2,y2,z2)
+		local x,z
+		local d = 0.0
+		
+		for z=z1,z2 do
+		for x=x1,x2 do
+			d = d + calcdens_pillar(x,z,y1,y2)
+		end
+		end
+		
+		return d/((x2-x1+1)*(z2-z1+1))
+	end
+	
+	--print("TEST: Calculate air density")
+	--print(calcdens(0,0,0,xlen-1,ylen-1,zlen-1))
+	
+	-- initialise light map
+	print("Initialising light map")
+	local lm = {}
+	for z=0,zlen-1 do
+		lm[z] = {}
+		for x=0,xlen-1 do
+			local l = common.map_pillar_get(x,z)
+			local lma = {}
+			i = 1
+			local lti = 0
+			local lt = 1.0
+			local bn = nil
+			local le = 0
+			while true do
+				local n = l[i+0]
+				local tn = (l[i+2]-l[i+1]+1)
+				local rn = (n ~= 0 and n-1) or tn
+				local nbn = rn-tn
+				
+				if bn then
+					local ca = l[i+3]-bn
+					for j=le+1,ca do
+						lt = lt * 0.8
+					end
+					for j=1,bn do
+						lti = lti + 1
+						lma[lti] = lt
+						lt = lt * 0.8
+					end
+				end
+				le = l[i+2]
+				bn = nbn
+				
+				lti = lti + 1
+				lma[lti] = nil
+				i = i + n*4
+				
+				for j=1,tn do
+					lti = lti + 1
+					lma[lti] = lt
+					lt = lt * 0.8
+				end
+				
+				if n == 0 then break end
+			end
+			lma.len = lti
+			lm[z][x] = lma
+		end
+	end
+	
+	-- spread
+	-- TODO!
+	
+	-- apply lightmap
+	print("Applying lightmap")
+	for z=0,zlen-1 do
+		for x=0,xlen-1 do
+			local l = common.map_pillar_get(x,z)
+			local lma = lm[z][x]
+			for i=1,lma.len do
+				if lma[i] then
+					local lt = math.max(0.2,math.min(1.0,lma[i]))
+					for j=1,3 do
+						local ci = (i-1)*4+j
+						l[ci] = math.floor(lt*l[ci]+0.5)
+					end
+				end
+			end
+			common.map_pillar_set(x,z,l)
+		end
+	end
+	
+	-- clean up
+	lm = nil
+
+	print("TODO: nicer stuff")
+	-- done!
+	print("Lighting done")
+end
+
+do
+	local densbase = 0.01
+	local h_tick_main_old = h_tick_main
+	h_tick_main = function (sec_current, sec_delta)
+		local ret = h_tick_main_old(sec_current, sec_delta)
+		local cx,cy,cz
+		cx,cy,cz = client.camera_get_pos()
+		local dens = calcdens(
+			math.floor(cx+0.5-5),
+			math.floor(cy+0.5-7),
+			math.floor(cz+0.5-5),
+			math.floor(cx+0.5+5),
+			math.floor(cy+0.5+3),
+			math.floor(cz+0.5+5))
+		
+		densbase = densbase + (dens - densbase) * (1.0-math.exp(-3.0*sec_delta))
+		
+		client.map_fog_set(
+			math.floor(0.5+192*densbase),
+			math.floor(0.5+238*densbase),
+			math.floor(0.5+255*densbase),
+			math.floor(0.5+60*densbase))
+		
+		return ret
+	end
+end
diff --git a/pkg/iceball/radtest/main_client.lua b/pkg/iceball/radtest/main_client.lua
new file mode 100644
index 0000000..0d35a9a
--- /dev/null
+++ b/pkg/iceball/radtest/main_client.lua
@@ -0,0 +1,20 @@
+--[[
+    This file is part of Ice Lua Components.
+
+    Ice Lua Components is free software: you can redistribute it and/or modify
+    it under the terms of the GNU Lesser General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    Ice Lua Components is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU Lesser General Public License for more details.
+
+    You should have received a copy of the GNU Lesser General Public License
+    along with Ice Lua Components.  If not, see <http://www.gnu.org/licenses/>.
+]]
+
+-- Example mod. NOT RELIABLE.
+
+loadfile("pkg/base/main_client.lua")(...)
diff --git a/pkg/iceball/radtest/main_server.lua b/pkg/iceball/radtest/main_server.lua
new file mode 100644
index 0000000..37e481d
--- /dev/null
+++ b/pkg/iceball/radtest/main_server.lua
@@ -0,0 +1,21 @@
+--[[
+    This file is part of Ice Lua Components.
+
+    Ice Lua Components is free software: you can redistribute it and/or modify
+    it under the terms of the GNU Lesser General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    Ice Lua Components is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU Lesser General Public License for more details.
+
+    You should have received a copy of the GNU Lesser General Public License
+    along with Ice Lua Components.  If not, see <http://www.gnu.org/licenses/>.
+]]
+
+-- Example mod. NOT RELIABLE.
+
+loadfile("pkg/base/main_server.lua")(...)
+