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diff --git a/display_lib/API.md b/display_lib/API.md
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+# Display Lib API
+This document describes Display Lib API. Display Lib allows to add a dynamic display on a node. Node must be wallmounted and Display Lib limits its rotation to vertical positions. 
+## Provided methods
+### update\_entities
+**display\_lib.update\_entities(pos)**
+
+This method triggers entities update for the display node at pos. Actual entity update is made by **on\_display\_update** callback associated to the entity.
+
+**pos**: Position of the node
+### register\_display\_entity
+**display\_lib.register\_display\_entity(entity_name)**
+
+This is a helper to register entities used for display. 
+
+**entity_name**: Name of the entity to register.
+## Provided callback implementations
+### on_place
+**display\_lib.on\_place(itemstack, placer, pointed\_thing)**
+
+**On_place** node callback implementation. Display nodes should have this callback (avoid placement of horizontal display node).
+### on_construct
+**display\_lib.on\_construct(pos)**
+
+**On_construct** node callback implementation. Display nodes should have this callback (creates, places and updates display entities on node construction).
+### on_destruct
+**display\_lib.on_destruct(pos)**
+
+**On_destruct** node callback implementation. Display nodes should have this callback (removes display entities on node destruction). 
+### on_rotate
+**display\_lib.on\_rotate(pos, node, user, mode, new_param2)**
+
+**On_rotate** node callback implementation. Display nodes should have this callback (restricts rotations and rotates display entities associated with node).
+### on_activate
+**display\_lib.on_activate(entity, staticdata)**
+
+**On_activate** entity callback implementation for display entities. No need of this method if display entities have been registered using **register\_display\_entity** (callback is already set). 
+## Howto register a display node
+* Register display entities with **register\_display\_entity**
+* Register node with :
+	- **on\_place**, **on\_construct**, **on\_destruct** and **on\_rotate** callbacks using **display\_lib** callbacks.
+	- a **display\_entities** field in node definition containing a entity name indexed table. For each entity, two fields : **depth** indicates the entity position (-0.5 to 0.5) and **on_display_update** is a callback in charge of setting up entity texture.
+
+### Example
+
+		display_lib.register_display_entity("mymod:entity1")
+		display_lib.register_display_entity("mymod:entity2")
+
+		function my_display_update1(pos, objref) 
+			objref:set_properties({ textures= {"mytexture1.png"},
+									visual_size = {x=1, y=1} })
+		end
+
+		function my_display_update2(pos, objref) 
+			objref:set_properties({ textures= {"mytexture2.png"},
+									visual_size = {x=1, y=1} })
+		end
+
+		minetest.register_node("mymod:test_display_node", {
+			...
+			paramtype2 = "wallmounted",
+			...
+			display_entities = {
+				["mymod:entity1"] = { depth = -0.3, 
+					on_display_update = my_display_update1},
+				["mymod:entity1"] = { depth = -0.2, 
+					on_display_update = my_display_update2},
+			},
+			...
+			on_place = display_lib.on_place,
+			on_construct = display_lib.on_construct,
+			on_destruct = display_lib.on_destruct,
+			on_rotate = display_lib.on_rotate,
+			...
+		})
+
+
+
diff --git a/display_lib/LICENSE.txt b/display_lib/LICENSE.txt
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--- /dev/null
+++ b/display_lib/LICENSE.txt
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+          DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE
+                   Version 2, December 2004
+ 
+Copyright (C) 2004 Sam Hocevar <sam@hocevar.net>
+ 
+Everyone is permitted to copy and distribute verbatim or modified
+copies of this license document, and changing it is allowed as long
+as the name is changed.
+ 
+           DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE
+  TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
+ 
+ 0. You just DO WHAT THE FUCK YOU WANT TO.
diff --git a/display_lib/README.md b/display_lib/README.md
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+++ b/display_lib/README.md
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+# Dislpay Lib
+
+This library's purpose is to ease creation of wallmounted nodes with a display on front side. For example, signs and clocks. Display can be dynamic and/or different for each node instance.
+
+**Limitations**: This lib uses entities to draw display. This means display has to be vertical. So display nodes are only wallmounted vertically.
+
+**Dependancies**:default
+
+**License**: WTFPL
+
+**API**: See API.md document please.
diff --git a/display_lib/depends.txt b/display_lib/depends.txt
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+++ b/display_lib/depends.txt
@@ -0,0 +1 @@
+default
diff --git a/display_lib/init.lua b/display_lib/init.lua
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index 0000000..eaddfd3
--- /dev/null
+++ b/display_lib/init.lua
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+-- Display lib mod by P.Y. Rollo
+--
+-- License: WTFPL
+
+display_lib = {}
+
+-- Miscelaneous values depending on wallmounted param2
+local wallmounted_values = {
+	[0]={dx=0,  dz=0,  lx=0, lz=0,  yaw=0,          rotate=0}, -- Should never be used
+		{dx=1,  dz=0,  lx=0, lz=0,  yaw=0,          rotate=1}, -- Should never be used 
+		{dx=1,  dz=0,  lx=0, lz=-1, yaw=-math.pi/2, rotate=4},
+		{dx=-1, dz=0,  lx=0, lz=1,  yaw=math.pi/2,  rotate=5},
+		{dx=0,  dz=1,  lx=1, lz=0,  yaw=0,          rotate=3},
+		{dx=0,  dz=-1, lx=-1, lz=0, yaw=math.pi,    rotate=2}
+}
+
+--- Gets the display entities attached with a node. Removes extra ones
+local function get_entities(pos)
+	local objrefs = {}
+	local ndef = minetest.registered_nodes[minetest.get_node(pos).name]
+	if ndef and ndef.display_entities then
+		for _, objref in ipairs(minetest.get_objects_inside_radius(pos, 0.5)) do
+			local entity = objref:get_luaentity()
+		    if entity and ndef.display_entities[entity.name] then
+				if objrefs[entity.name] then
+				    objref:remove()
+				else
+					objrefs[entity.name] = objref
+				end
+		    end
+		end
+	end
+	return objrefs
+end
+
+local function clip_pos_prop(posprop)
+	if posprop then
+		return math.max(-0.5, math.min(0.5, posprop))
+	else
+		return 0
+	end
+end
+
+--- (Create and) place display entities according to the node orientation
+local function place_entities(pos)
+	local node = minetest.get_node(pos)
+	local ndef = minetest.registered_nodes[node.name]
+	local values = wallmounted_values[node.param2]
+	local objrefs = get_entities(pos)
+
+	if ndef and ndef.display_entities then
+		for entity_name, props in pairs(ndef.display_entities) do
+			local depth = clip_pos_prop(props.depth)
+			local top = clip_pos_prop(props.top)
+			local left = clip_pos_prop(props.left)
+			
+			if not objrefs[entity_name] then
+				objrefs[entity_name] = minetest.add_entity(pos, entity_name)
+			end
+
+			objrefs[entity_name]:setpos({
+				x = pos.x - values.dx * depth + values.lx * left,
+				y = pos.y + top,
+				z = pos.z - values.dz * depth + values.lz * left})
+
+			objrefs[entity_name]:setyaw(values.yaw)
+		end
+	end
+	return objrefs
+end
+
+--- Call on_display_update callback of a node for one of its display entities
+local function call_node_on_display_update(pos, objref)
+	local ndef = minetest.registered_nodes[minetest.get_node(pos).name]
+	local entity = objref:get_luaentity()
+	if ndef and ndef.display_entities and entity and ndef.display_entities[entity.name] then
+		ndef.display_entities[entity.name].on_display_update(pos, objref)
+	end	
+end
+
+--- Force entity update
+function display_lib.update_entities(pos)
+	local objrefs = place_entities(pos)
+	for _, objref in pairs(objrefs) do
+		call_node_on_display_update(pos, objref)
+    end
+end
+
+--- On_activate callback for display_lib entities. Calls on_display_update callbacks 
+--- of corresponding node for each entity.
+function display_lib.on_activate(entity, staticdata)
+	if entity then
+		call_node_on_display_update(entity.object:getpos(), entity.object)
+	end
+end
+
+--- On_place callback for display_lib items. Does nothing more than preventing item
+--- from being placed on ceiling or ground 
+function display_lib.on_place(itemstack, placer, pointed_thing)
+	local above = pointed_thing.above
+	local under = pointed_thing.under
+	local dir = {x = under.x - above.x,
+				 y = under.y - above.y,
+				 z = under.z - above.z}
+	local wdir = minetest.dir_to_wallmounted(dir)
+
+	if wdir == 0 or wdir == 1 then
+		dir = placer:get_look_dir()
+		dir.y = 0
+		wdir = minetest.dir_to_wallmounted(dir)
+	end
+	return minetest.item_place(itemstack, placer, pointed_thing, wdir) 
+end
+
+--- On_construct callback for display_lib items. Creates entities and update them.
+function display_lib.on_construct(pos)
+	display_lib.update_entities(pos)
+end
+
+--- On_destruct callback for display_lib items. Removes entities.
+function display_lib.on_destruct(pos)
+	local objrefs = get_entities(pos)
+	
+	for _, objref in pairs(objrefs) do 
+		objref:remove()
+	end
+end
+
+
+-- On_rotate (screwdriver) callback for display_lib items. Prevents axis rotation and reorients entities.
+function display_lib.on_rotate(pos, node, user, mode, new_param2)
+	if mode ~= screwdriver.ROTATE_FACE then return false end
+
+	if wallmounted_values[node.param2] then
+		minetest.swap_node(pos, {name = node.name, param1 = node.param1, param2 = wallmounted_values[node.param2].rotate})
+		place_entities(pos)
+		return true
+	else
+		return false
+	end
+end
+
+--- Creates display entity with some fields and the on_activate callback
+function display_lib.register_display_entity(entity_name)
+	if not minetest.registered_entity then
+		minetest.register_entity(':'..entity_name, {
+			collisionbox = { 0, 0, 0, 0, 0, 0 },
+			visual = "upright_sprite",
+			textures = {},
+			on_activate = display_lib.on_activate,
+		})
+	end
+end
+
+
+