diff --git a/scripts/devel/light.lua b/scripts/devel/light.lua
new file mode 100644
index 000000000..4152876ae
--- /dev/null
+++ b/scripts/devel/light.lua
@@ -0,0 +1,238 @@
+-- an experimental lighting engine for df
+local gui = require 'gui'
+local guidm = require 'gui.dwarfmode'
+local render = require 'plugins.rendermax'
+
+local levelDim=0.05
+local tile_attrs = df.tiletype.attrs
+
+local args={...}
+
+function setCell(x,y,cell)
+	cell=cell or {}
+	cell.fm=cell.fm or {r=1,g=1,b=1}
+	cell.bm=cell.bm or {r=1,g=1,b=1}
+	cell.fo=cell.fo or {r=0,g=0,b=0}
+	cell.bo=cell.bo or {r=0,g=0,b=0}
+	render.setCell(x,y,cell)
+end
+function getCursorPos()
+	local g_cursor=df.global.cursor
+    if g_cursor.x ~= -30000 then
+        return copyall(g_cursor)
+    end
+end
+function falloff(color,sqDist,maxdist)
+	local v1=1/(sqDist/maxdist+1)
+	local v2=v1-1/(1+maxdist*maxdist)
+	local v=v2/(1-1/(1+maxdist*maxdist))
+	return {r=v*color.r,g=v*color.g,b=v*color.b}
+end
+function blend(c1,c2)
+return {r=math.max(c1.r,c2.r),
+		g=math.max(c1.g,c2.g),
+		b=math.max(c1.b,c2.b)}
+end
+LightOverlay=defclass(LightOverlay,guidm.DwarfOverlay)
+LightOverlay.ATTRS {
+    lightMap={},
+	dynamic=true
+}
+function LightOverlay.init(args)
+end
+
+function lightPassable(shape)
+	if shape==df.tiletype_shape.WALL or
+	   shape==df.tiletype_shape.BROOK_BED or
+	   shape==df.tiletype_shape.TREE then
+	   return false
+	else
+		return true
+	end
+end
+function LightOverlay:placeLightFov(pos,radius,color,f,rays)
+	f=f or falloff
+	local raycount=rays or 25
+	local vp=self:getViewport()
+	local map = self.df_layout.map
+	local off=math.random(0,math.pi)
+	local done={}
+	for d=0,math.pi*2,math.pi*2/raycount do
+		local dx,dy
+		dx=math.cos(d+off)
+		dy=math.sin(d+off)
+		local cx=0
+		local cy=0
+		
+		for dt=0,radius,0.01 do
+			if math.abs(math.floor(dt*dx)-cx)>0 or math.abs(math.floor(dt*dy)-cy)> 0then
+				local x=cx+pos.x
+				local y=cy+pos.y
+				
+				if x>0 and y>0 and x<=map.width and y<=map.height and not done[tile] then
+					local tile=x+y*map.width
+					done[tile]=true
+					local ncol=f(color,dt*dt,radius)
+					local ocol=self.lightMap[tile] or {r=0,g=0,b=0}
+					ncol=blend(ncol,ocol)
+					self.lightMap[tile]=ncol
+					
+					
+					if --(ncol.r==ocol.r and ncol.g==ocol.g and ncol.b==ocol.b) or
+						 not self.ocupancy[tile] then
+						break
+					end
+				end
+				cx=math.floor(dt*dx)
+				cy=math.floor(dt*dy)
+			end
+		end
+	end
+end
+function LightOverlay:placeLight(pos,radius,color,f)
+	f=f or falloff
+	local vp=self:getViewport()
+	local map = self.df_layout.map
+
+	for i=-radius,radius do
+	for j=-radius,radius do
+		local x=pos.x+i+1
+		local y=pos.y+j+1
+		if x>0 and y>0 and x<=map.width and y<=map.height then
+			local tile=x+y*map.width
+			local ncol=f(color,(i*i+j*j),radius)
+			local ocol=self.lightMap[tile] or {r=0,g=0,b=0}
+			self.lightMap[tile]=blend(ncol,ocol)
+		end
+	end
+	end
+end
+function LightOverlay:calculateLightLava()
+	local vp=self:getViewport()
+	local map = self.df_layout.map
+	for i=map.x1,map.x2 do
+	for j=map.y1,map.y2 do
+		local pos={x=i+vp.x1-1,y=j+vp.y1-1,z=vp.z}
+		local pos2={x=i+vp.x1-1,y=j+vp.y1-1,z=vp.z-1}
+		local t1=dfhack.maps.getTileFlags(pos)
+		local shape=tile_attrs[dfhack.maps.getTileType(pos)].shape
+		local t2=dfhack.maps.getTileFlags(pos2)
+		if  (t1 and t1.liquid_type and t1.flow_size>0) or 
+			(shape==df.tiletype_shape.EMPTY and t2 and t2.liquid_type and t2.flow_size>0) then
+			--self:placeLight({x=i,y=j},5,{r=0.8,g=0.2,b=0.2})
+			self:placeLightFov({x=i,y=j},5,{r=0.8,g=0.2,b=0.2},nil,5)
+		end
+	end
+	end
+end
+function LightOverlay:calculateLightSun()
+	local vp=self:getViewport()
+	local map = self.df_layout.map
+	for i=map.x1,map.x2+1 do
+	for j=map.y1,map.y2+1 do
+		local pos={x=i+vp.x1-1,y=j+vp.y1-1,z=vp.z}
+		
+		local t1=dfhack.maps.getTileFlags(pos)
+		
+		if  (t1 and t1.outside ) then
+			
+			self:placeLightFov({x=i,y=j},7,{r=1,g=1,b=1},nil,3)
+		end
+	end
+	end
+end
+function LightOverlay:calculateLightCursor()
+	local c=getCursorPos()
+	
+	if c then
+		
+		local vp=self:getViewport()
+		local pos=vp:tileToScreen(c)
+		--self:placeLight(pos,11,{r=0.96,g=0.84,b=0.03})
+		self:placeLightFov({x=pos.x+1,y=pos.y+1},11,{r=0.96,g=0.84,b=0.03})
+		
+	end
+end
+function LightOverlay:buildOcupancy()
+	self.ocupancy={}
+	local vp=self:getViewport()
+	local map = self.df_layout.map
+	for i=map.x1,map.x2+1 do
+	for j=map.y1,map.y2+1 do
+		local pos={x=i+vp.x1-1,y=j+vp.y1-1,z=vp.z}
+		local tile=i+j*map.width
+		local tt=dfhack.maps.getTileType(pos)
+		
+		if tt then
+			local shape=tile_attrs[tt].shape
+			self.ocupancy[tile]=lightPassable(shape)
+		end
+	end
+	end
+	
+end
+function LightOverlay:makeLightMap()
+	self.lightMap={}
+	self:buildOcupancy()
+	self:calculateLightCursor()
+	self:calculateLightLava()
+	self:calculateLightSun()
+end
+function LightOverlay:onIdle()
+	self._native.parent:logic()
+	if self.dynamic then
+		self:makeLightMap()
+	end
+end
+function LightOverlay:render(dc)
+
+	
+	self:renderParent()
+	local vp=self:getViewport()
+	local map = self.df_layout.map
+	
+	self.lightMap=self.lightMap or {}
+	render.lockGrids()
+	df.global.gps.force_full_display_count=df.global.gps.force_full_display_count+1
+	render.resetGrids()
+	for i=map.x1,map.x2 do
+	for j=map.y1,map.y2 do
+		local v=self.lightMap[i+j*map.width]
+		if v then
+			setCell(i,j,{fm=v,bm=v})
+		else
+			local dimRgb={r=levelDim,g=levelDim,b=levelDim}
+			setCell(i,j,{fm=dimRgb,bm=dimRgb})
+		end
+	end
+	end
+	render.unlockGrids()
+	
+end
+function LightOverlay:onDismiss()
+	render.lockGrids()
+	render.resetGrids()
+	render.unlockGrids()
+	df.global.gps.force_full_display_count=df.global.gps.force_full_display_count+1
+end
+function LightOverlay:onInput(keys)
+	if keys.LEAVESCREEN then
+		self:dismiss()
+	else
+		self:sendInputToParent(keys)
+		
+		if keys.CHANGETAB then
+			self:updateLayout()
+		end
+		if keys.STRING_A126 and not self.dynamic then
+			self:makeLightMap()
+		end
+	end
+end
+if not render.isEnabled() then
+	qerror("Lua rendermode not enabled!")
+end
+local dyn=true
+if #args>0 and args[1]=="static" then dyn=false end
+local lview = LightOverlay{ dynamic=dyn}
+lview:show()
\ No newline at end of file