make sure digger is valid before checking for creative

(else assume survival)

README.md

@@ -22,7 +22,7 @@ That said, there are some basic text formatting options:
 
   Writing "^" followed by a letter "a" through "h" will produce double-wide versions of these arrows, in the same order.  These wide arrows occupy 0x89 to 0x91 in the character set.
 
-* A color may be specified in the sign text by using "#" followed by a single hexadcimal digit (0-9 or a-f).  These colors come from the standard Linux/IRC/CGA color set, and are shown in the sign's formspec.  Any color change will remain in effect until changed again, or until the next line break.  Any number of color changes in any arbitrary arrangement is allowed.
+* A color may be specified in the sign text by using "#" followed by a single hexadcimal digit (0-9 or a-f).  These colors come from the standard Linux/IRC/CGA color set, and are shown in the sign's formspec.  Any color change will remain in effect until changed again, or until the next line break.  Any number of color changes in any arbitrary arrangement is allowed. To write "#" on a sign, write "##".
 
 * Most writable signs can display double-wide text by flipping a switch in the sign's formspec.
 

api.lua

@@ -4,6 +4,8 @@ local S = signs_lib.gettext
 
 local function get_sign_formspec() end
 
+signs_lib.glow_item = "basic_materials:energy_crystal_simple"
+
 signs_lib.lbm_restore_nodes = {}
 signs_lib.old_fenceposts = {}
 signs_lib.old_fenceposts_replacement_signs = {}
@@ -180,7 +182,7 @@ function signs_lib.delete_objects(pos)
 	end
 end
 
-function signs_lib.spawn_entity(pos, texture)
+function signs_lib.spawn_entity(pos, texture, glow)
 	local node = minetest.get_node(pos)
 	local def = minetest.registered_items[node.name]
 	if not def or not def.entity_info then return end
@@ -229,6 +231,10 @@ function signs_lib.spawn_entity(pos, texture)
 		end
 	end
 
+	if glow ~= "" then
+		obj:set_properties( {glow = tonumber(glow * 5)} )
+	end
+
 	if yaw then
 		obj:set_rotation({x = pitch, y = yaw, z=0})
 
@@ -247,14 +253,15 @@ function signs_lib.spawn_entity(pos, texture)
 	end
 end
 
-function signs_lib.set_obj_text(pos, text)
+function signs_lib.set_obj_text(pos, text, glow)
 	local split = signs_lib.split_lines_and_words
 	local text_ansi = Utf8ToAnsi(text)
 	local n = minetest.registered_nodes[minetest.get_node(pos).name]
 	signs_lib.delete_objects(pos)
 	-- only create sign entity for actual text
 	if text_ansi and text_ansi ~= "" then
-		signs_lib.spawn_entity(pos, signs_lib.make_sign_texture(split(text_ansi), pos) )
+		signs_lib.spawn_entity(pos,
+				signs_lib.make_sign_texture(split(text_ansi), pos), glow)
 	end
 end
 
@@ -548,8 +555,9 @@ local function make_line_texture(line, lineno, pos, line_width, line_height, cwi
 				end
 			end
 			local c = word:sub(i, i)
-			if c == "#" then
-				local cc = tonumber(word:sub(i+1, i+1), 16)
+			local c2 = word:sub(i+1, i+1)
+			if c == "#" and c2 ~= "#" then
+				local cc = tonumber(c2, 16)
 				if cc then
 					i = i + 1
 					cur_color = cc
@@ -700,13 +708,19 @@ end
 
 function signs_lib.rightclick_sign(pos, node, player, itemstack, pointed_thing)
 
-	if not signs_lib.can_modify(pos, player) then return end
+	if not player or not signs_lib.can_modify(pos, player) then return end
 
 	player:get_meta():set_string("signslib:pos", minetest.pos_to_string(pos))
 	minetest.show_formspec(player:get_player_name(), "signs_lib:sign", get_sign_formspec(pos, node.name))
 end
 
 function signs_lib.destruct_sign(pos)
+	local meta = minetest.get_meta(pos)
+	local glow = meta:get_string("glow")
+	if glow ~= "" and not minetest.is_creative_enabled("") then
+		local num = tonumber(glow)
+		minetest.add_item(pos, ItemStack(signs_lib.glow_item .. " " .. num))
+	end
 	signs_lib.delete_objects(pos)
 end
 
@@ -720,6 +734,30 @@ local function make_infotext(text)
 	return table.concat(lines2, "\n")
 end
 
+function signs_lib.glow(pos, node, puncher)
+	local name = puncher:get_player_name()
+	if minetest.is_protected(pos, name) then
+		return
+	end
+	local tool = puncher:get_wielded_item()
+	if tool:get_name() == signs_lib.glow_item then
+		local meta = minetest.get_meta(pos)
+		local glow = tonumber(meta:get_string("glow"))
+		if not glow then
+			glow = 1
+		elseif glow < 3 then
+			glow = glow + 1
+		else
+			return -- already at brightest level
+		end
+		if not minetest.is_creative_enabled(name) then
+			tool:take_item()
+			puncher:set_wielded_item(tool)
+		end
+		meta:set_string("glow", glow)
+	end
+end
+
 function signs_lib.update_sign(pos, fields)
 	local meta = minetest.get_meta(pos)
 
@@ -737,7 +775,9 @@ function signs_lib.update_sign(pos, fields)
 
 	meta:set_string("text", text)
 	meta:set_string("infotext", ownstr..make_infotext(text).." ")
-	signs_lib.set_obj_text(pos, text)
+
+	local glow = meta:get_string("glow")
+	signs_lib.set_obj_text(pos, text, glow)
 end
 
 function signs_lib.can_modify(pos, player)
@@ -902,6 +942,23 @@ function signs_lib.register_fence_with_sign()
 	minetest.log("warning", "[signs_lib] ".."Attempt to call no longer used function signs_lib.register_fence_with_sign()")
 end
 
+local use_glow = function(pos, node, puncher, pointed_thing)
+	if puncher then -- if e.g. a machine tries to punch; only a real person should change the lighting
+		signs_lib.glow(pos, node, puncher)
+	end
+	return signs_lib.update_sign(pos)
+end
+
+local glow_drops = function(pos, oldnode, oldmetadata, digger)
+	if digger and minetest.is_creative_enabled(digger:get_player_name()) then
+		return
+	end
+	local glow = oldmetadata and oldmetadata.fields and oldmetadata.fields.glow
+	if glow then
+		minetest.add_item(pos, ItemStack(signs_lib.glow_item .. " " .. glow))
+	end
+end
+
 function signs_lib.register_sign(name, raw_def)
 	local def = table.copy(raw_def)
 
@@ -917,9 +974,16 @@ function signs_lib.register_sign(name, raw_def)
 	def.after_place_node = raw_def.after_place_node or signs_lib.after_place_node
 
 	if raw_def.entity_info then
+
+		if def.allow_glow ~= false then
+			def.on_punch        = raw_def.on_punch            or use_glow
+			def.after_dig_node  = raw_def.after_dig_node      or glow_drops
+		else
+			def.on_punch        = raw_def.on_punch            or signs_lib.update_sign
+		end
+
 		def.on_rightclick       = raw_def.on_rightclick       or signs_lib.rightclick_sign
 		def.on_destruct         = raw_def.on_destruct         or signs_lib.destruct_sign
-		def.on_punch            = raw_def.on_punch            or signs_lib.update_sign
 		def.number_of_lines     = raw_def.number_of_lines     or signs_lib.standard_lines
 		def.horiz_scaling       = raw_def.horiz_scaling       or signs_lib.standard_hscale
 		def.vert_scaling        = raw_def.vert_scaling        or signs_lib.standard_vscale
@@ -1228,16 +1292,17 @@ function get_sign_formspec(pos, nodename)
 
 	local formspec = {
 		"size[6,4]",
-		"textarea[0,-0.3;6.5,3;text;;" .. minetest.formspec_escape(txt) .. "]",
-		"background[-0.5,-0.5;7,5;signs_lib_sign_bg.jpg]",
-		"button_exit[2,3.4;2,1;ok;" .. S("Write") .. "]"
+		"background[-0.5,-0.5;7,5;signs_lib_sign_bg.png]",
+		"image[0.1,2.4;7,1;signs_lib_sign_color_palette.png]", 
+		"textarea[0.15,-0.2;6.3,2.8;text;;" .. minetest.formspec_escape(txt) .. "]",
+		"button_exit[3,3.4;2,1;ok;" .. S("Write") .. "]"
 	}
 
 	if minetest.registered_nodes[nodename].allow_widefont then
 		local state = "off"
 		if meta:get_int("widefont") == 1 then state = "on" end
-		formspec[5] = "label[0.5,3.4;Use wide font]"
-		formspec[6] = "image_button[0.6,3.7;1,0.6;signs_lib_switch_" .. state .. ".png;"
+		formspec[#formspec+1] = "label[0.9,3.4;Use wide font]"
+		formspec[#formspec+1] = "image_button[1.1,3.7;1,0.6;signs_lib_switch_" .. state .. ".png;"
 				.. state .. ";;;false;signs_lib_switch_interm.png]"
 	end
 

mod.conf

@@ -3,4 +3,4 @@ author = VanessaE
 depends = default
 optional_depends = intllib, screwdriver, streetspoles, streetlamps, cottages, prefab_redo
 description = Adds signs with readable text.
-min_minetest_version = 5.2.0
+min_minetest_version = 5.4.0