We now point non-player entities away from portal, Looks really good with

mobs like rats and sheep.

README.txt

@@ -76,6 +76,7 @@ old portalgun_portals table)
  20151011 When a player is teleported and the exit portal points x+,
 x-, z+ or z-, we now set their look direction appropriately so they
 have their back to the portal they just emerged from.
+ 20151012 Set yaw of non-player entities as they emerge from a portal
 
 
 TODO - BUG FIXES

init.lua

@@ -35,6 +35,68 @@ local function node_ok(pos)
     return minetest.registered_nodes[fallback]
 end
 
+-- try to figure out the object's physical height. There are
+-- several cases that need to be handled. Not all objects
+-- have a collisionbox
+local function object_height(ob)
+	if ob:is_player() then
+		-- We assume players have a height of 1.8 metres
+		print "object_height: is player, returning 1.8"
+		return 1.8
+	end
+
+	local ent = ob:get_luaentity()
+	if ent then
+		local cb = ent.collisionbox;
+		if cb then
+			-- We got lucky, an object whose entity actually defines a
+			-- collisionbox! The height is in cb[5]
+			print("object_height: cb ("..cb[1]..", "..cb[2]..", "..cb[3]
+							..", "..cb[4]..", "..cb[5]..", "..cb[6]..")")
+			return cb[5]
+		elseif ent.name=="__builtin:item" then
+			local iname = ItemStack(ent.itemstring):get_name()
+			print("object_height: dropped obj '"..ent.itemstring
+				.."', iname '"..iname.."'")
+			cb = minetest.registered_entities[ent.name].collisionbox
+			if cb == nil then
+				cb = minetest.registered_items[iname].collisionbox
+			end
+			if cb then
+				-- This seems to never happen
+				print("  found cb ("..cb[1]..", "..cb[2]..", "..cb[3]
+					..", "..cb[4]..", "..cb[5]..", "..cb[6]..")")
+				return cb[5]
+			else
+				-- Try to get the visual attribute, but it is never available
+				local vs = minetest.registered_entities[ent.name].visual
+				print("  no cb, visual '"..minetest.serialize(vs).."'")
+				-- TODO: Can we test what version of the Minetest engine
+				-- we're in? The size of __builtin:item objects changed,
+				-- look in game/item_entity.lua for a call to register_entity
+				-- it used to be about 0.33 and is presently 0.6
+				return 0.6
+			end
+		else
+			print("object_height: entity '"..ent.name.."'")
+			cb = minetest.registered_entities[ent.name].collisionbox
+			if cb then
+				-- This seems to never happen
+				print("  found cb ("..cb[1]..", "..cb[2]..", "..cb[3]
+					..", "..cb[4]..", "..cb[5]..", "..cb[6]..")")
+				return cb[5]
+			else
+				print("  no cb, assume small")
+			end
+		end
+	else
+		-- we couldn't get a laentity
+	end
+
+	-- if we get here we couldn't figure it out at all.
+	return 0.1
+end
+
 minetest.register_on_leaveplayer(
 	-- when a player leaves the game, make their portals expire
 	function(user)
@@ -95,6 +157,12 @@ local function portalgun_step_proc(portal, id)
 		-- to catch players, whose "position" is a point near the feet)
 		for ii, ob in pairs(minetest.get_objects_inside_radius(pos1, 1.5)) do
 			local ent = ob:get_luaentity()
+
+			-- TODO: use object height to get a more refined sense of the
+			-- object's true distance from the portal, and ignore if object
+			-- is not within a closer radius
+			-- local height = object_height(ob)
+
 			if ent and ent.name == "portalgun:portal" then
 				-- this object is the portal itself; ignore
 			else
@@ -116,12 +184,6 @@ local function portalgun_step_proc(portal, id)
 
 					-- compute the magnitude of the velocity
 					local vmag = math.sqrt(v.x*v.x + v.y*v.y + v.z*v.z)
-					-- if v.x<0 then v.x=v.x*-1 end
-					-- if v.y<0 then v.y=v.y*-1 end
-					-- if v.z<0 then v.z=v.z*-1 end
-					-- local vmag=0 -- get the biggest velocity
-					-- if v.x>v.z then vmag=v.x else vmag=v.z end
-					-- if vmag<v.y then vmag=v.y end
 
 					-- compute exit velocity. Objects always exit in a
 					-- direction perpendicular to the exit portal, with
@@ -131,16 +193,20 @@ local function portalgun_step_proc(portal, id)
 					v.z = 0
 					if d2 == "x+" then
 						v.x = vmag
+						ob:setyaw(math.pi/-2)
 					elseif d2 == "x-" then
 						v.x = vmag*-1
+						ob:setyaw(math.pi/2)
 					elseif d2 == "y+" then
 						v.y = vmag
 					elseif d2 == "y-" then
 						v.y = vmag*-1
 					elseif d2 == "z+" then
 						v.z = vmag
+						ob:setyaw(0)
 					elseif d2 == "z-" then
 						v.z = vmag*-1
+						ob:setyaw(math.pi)
 					end
 
 					ob:setvelocity({x = v.x, y = v.y, z = v.z})
@@ -150,6 +216,8 @@ local function portalgun_step_proc(portal, id)
 				-- in whatever direction the exit portal is facing. It has
 				-- to be 2 nodes away so we don't immediately get
 				-- teleported again.
+				-- TODO: Once we manage to decrease the capture radius of 1.5,
+				-- we may also diminish this distance.
 				if d2 == "x+" then x = 2
 				elseif d2 == "x-" then x = -2
 				elseif d2 == "y+" then y = 2
@@ -412,6 +480,7 @@ local function portal_useproc(itemstack, user, pointed_thing, RMB, remove)
 				id_p0rtal[id].portal1 = obj
 			end
 			if obj then
+				-- fill in its staticdata
 				local ent = obj:get_luaentity()
 				if ent then
 					ent.owner = uname
@@ -430,7 +499,7 @@ local function portal_useproc(itemstack, user, pointed_thing, RMB, remove)
 				op_prtl[op] = {}
 			end
 			op_prtl[op].pnum = pnum
-			op_prtl[op].portal = portal
+			op_prtl[op].portal = obj
 			op_prtl[op].owner = uname
 			op_prtl[op].pos = cpos
 			op_prtl[op].dir = portal_dir