Implement new transmissive mirror physics (WIP)

mods/lzr_laser/blocks.lua

@@ -80,7 +80,14 @@ end
 
 -- Mirror a laser that touches a mirror at mirror_pos with a laser coming towards
 -- the mirror with the laser_dir direction (direction vector).
--- Returns the "output direction" of the laser or false if can't get mirrored.
+-- Returns <output direction>, <mirror output side>
+-- 	1) If the laser can be mirrored, then <output direction> is the direction of
+-- 	the mirrored laser and <mirror output> denotes on of the 2 possible
+-- 	sides the laser came from: true if it came in the front side, false if
+-- 	it came from the angled side. <mirror output> is useful for the
+-- 	transmissive mirror.
+-- 	2) If the laser cannot be mirrored <mirror output> is false and
+-- 	<mirror output side> is nil
 lzr_laser.get_mirrored_laser_dir = function(mirror_pos, laser_dir)
 	local mirror = minetest.get_node(mirror_pos)
 	local mirror_group = minetest.get_item_group(mirror.name, "mirror")
@@ -94,9 +101,9 @@ lzr_laser.get_mirrored_laser_dir = function(mirror_pos, laser_dir)
 		return false
 	end
 	if vector.equals(reverse_laser_dir, mirror_dir_in) then
-		return mirror_dir_out
+		return mirror_dir_out, true
 	elseif vector.equals(reverse_laser_dir, mirror_dir_out) then
-		return mirror_dir_in
+		return mirror_dir_in, false
 	end
 	return false
 end
@@ -201,6 +208,9 @@ local register_element = function(subname, def, options)
 	if options.not_walkable_if_off then
 		def_core.walkable = false
 	end
+	if options.allow_take then
+		def_core._lzr_takable = "lzr_laser:"..subname.."_takable"
+	end
 
 	def_core.description = S("@1 (fixed)", def.description)
 	def_core.after_dig_node = full_update
@@ -214,7 +224,13 @@ local register_element = function(subname, def, options)
 		def_core.groups = {}
 	end
 	def_core.groups.breakable = 1
-	def_core.groups[subname] = 1
+	local groupname
+	if options.group then
+		groupname = options.group
+	else
+		groupname = subname
+	end
+	def_core.groups[groupname] = 1
 	def_core.can_dig = element_can_dig
 	def_core.on_place = element_on_place
 
@@ -237,7 +253,10 @@ local register_element = function(subname, def, options)
 		if not options.keep_state_on_take then
 			def_core_on.drop = "lzr_laser:"..subname
 		end
-		def_core_on.groups[subname] = 2
+		if options.allow_take then
+			def_core_on._lzr_takable = "lzr_laser:"..subname.."_takable_on"
+		end
+		def_core_on.groups[groupname] = 2
 		def_core_on.light_source = def.light_source_on
 		minetest.register_node("lzr_laser:"..subname.."_on", def_core_on)
 	end
@@ -246,12 +265,14 @@ local register_element = function(subname, def, options)
 		local def_takable = table.copy(def_core)
 		def_takable.tiles = def.tiles_takable_off
 		def_takable.groups.takable = 1
+		def_takable._lzr_untakable = "lzr_laser:"..subname
 		def_takable.description = def.description
 		minetest.register_node("lzr_laser:"..subname.."_takable", def_takable)
 
 		if options.activate ~= false then
 			def_takable._lzr_active = "lzr_laser:"..subname.."_takable_on"
 			local def_takable_on = table.copy(def_core_on)
+			def_takable_on._lzr_untakable = "lzr_laser:"..subname.."_on"
 			def_takable_on.tiles = def.tiles_takable_on
 			def_takable_on.light_source = def.light_source_on
 			def_takable_on.groups.takable = 1
@@ -326,10 +347,15 @@ local tm_def = {
 	groups = { rotatable = 1, laser_block = 1 },
 	sounds = lzr_sounds.node_sound_glass_defaults({
 		_rotate = {name = "lzr_laser_mirror_rotate", gain = 1.0},
-	})
+	}),
+	_lzr_transmissive_mirror_00 = "lzr_laser:transmissive_mirror_00",
+	_lzr_transmissive_mirror_01 = "lzr_laser:transmissive_mirror_01",
+	_lzr_transmissive_mirror_10 = "lzr_laser:transmissive_mirror_10",
+	_lzr_transmissive_mirror_11 = "lzr_laser:transmissive_mirror_11",
 }
 
 local tm_def_off = table.copy(tm_def)
+tm_def_off._lzr_transmissive_mirror_state = "00"
 tm_def_off.tiles_off = {
 	{name="lzr_laser_transmissive_mirror_block.png^lzr_laser_fixed.png", backface_culling=true},
 	{name="lzr_laser_transmissive_mirror_mirror.png", backface_culling=true},
@@ -341,8 +367,14 @@ tm_def_off.tiles_takable_off = {
 	{name="lzr_laser_transmissive_mirror_mirror_out.png", backface_culling=true},
 }
 tm_def_off.mesh_off = "lzr_laser_mirror.obj"
+-- Use custom fields to identify transmissive mirror states
 
+
+-- Transmissive Mirror
+-- FIXME: Takable Transmissive Mirror becomes fixed after full laser update
 local tm_def_on_01 = table.copy(tm_def)
+tm_def_on_01._lzr_transmissive_mirror_state = "01"
+tm_def_on_01._lzr_inactive = "lzr_laser:transmissive_mirror_00"
 tm_def_on_01.description = S("Transmissive Mirror (active, 01)")
 tm_def_on_01.tiles_off = {
 	{name="lzr_laser_laser_full.png", backface_culling=true},
@@ -359,17 +391,20 @@ tm_def_on_01.tiles_takable_off = {
 tm_def_on_01.mesh_off = "lzr_laser_mirror_on_thru1.obj"
 
 local tm_def_on_10 = table.copy(tm_def_on_01)
+tm_def_on_10._lzr_transmissive_mirror_state = "10"
 tm_def_on_10.description = S("Transmissive Mirror (active, 10)")
 tm_def_on_10.mesh_off = "lzr_laser_mirror_on_thru2.obj"
 
 local tm_def_on_11 = table.copy(tm_def_on_01)
+tm_def_on_11._lzr_transmissive_mirror_state = "11"
 tm_def_on_11.description = S("Transmissive Mirror (active, 11)")
 tm_def_on_11.mesh_off = "lzr_laser_mirror_on_thru3.obj"
 
-register_element("transmissive_mirror", tm_def_off, { allow_take = true, activate = false })
-register_element("transmissive_mirror_on_01", tm_def_on_01, { allow_take = true, activate = false })
-register_element("transmissive_mirror_on_10", tm_def_on_10, { allow_take = true, activate = false })
-register_element("transmissive_mirror_on_11", tm_def_on_11, { allow_take = true, activate = false })
+local tm_options = { allow_take = true, activate = false, group = "transmissive_mirror" }
+register_element("transmissive_mirror_00", tm_def_off, tm_options)
+register_element("transmissive_mirror_01", tm_def_on_01, tm_options)
+register_element("transmissive_mirror_10", tm_def_on_10, tm_options)
+register_element("transmissive_mirror_11", tm_def_on_11, tm_options)
 
 register_element("crystal", {
 	description = S("Crystal"),

mods/lzr_laser/physics.lua

@@ -83,14 +83,30 @@ function lzr_laser.add_laser(pos, dir, varea, vdata)
 		end
 	-- Mirror and split laser
 	elseif minetest.get_item_group(nodename, "transmissive_mirror") > 0 then
-		local mirror_dir = lzr_laser.get_mirrored_laser_dir(pos, dir)
+		local mirror_dir, mirror_side = lzr_laser.get_mirrored_laser_dir(pos, dir)
 		if mirror_dir then
 			local def = minetest.registered_nodes[nodename]
-			local active = def._lzr_active
-			if not active then
+			local state = def._lzr_transmissive_mirror_state
+			if not state then
+				minetest.log("error", "[lzr_laser] Transmissive mirror node '"..nodename.."' does not have _lzr_transmissive_mirror_state!")
 				return false
 			end
-			-- Activate mirror node
+			if mirror_side == true then
+				state = lzr_laser.bitwise_or(state, "01")
+			else
+				state = lzr_laser.bitwise_or(state, "10")
+			end
+			local active = def["_lzr_transmissive_mirror_"..state]
+			if not active then
+				minetest.log("error", "[lzr_laser] Missing transmissive mirror node state for '"..nodename.."!")
+				return false
+			end
+			local is_takable = minetest.get_item_group(nodename, "takable") ~= 0
+			if is_takable then
+				local def_active = minetest.registered_nodes[active]
+				active = def_active._lzr_takable
+			end
+			-- Set new transmissive node state
 			vdata[vi] = minetest.get_content_id(active)
 			-- Set new pos and dir
 			local pos_straight = vector.add(pos, dir)