Fix healthbar HUD (#981)

* Fix healthbar HUD

* Add texture for "gone" heart

* Right-align HP bar

mods/ctf/ctf_map/ctf_map_core/maps

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+Subproject commit fa7fa3e8f80dd82d6e98766581269817325e546b

mods/other/hpbar_hud/init.lua

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+local ids = {}
+
+local texture_res = 24 -- heart texture resolution
+
+local function calculate_offset(hearts)
+	return {x = (-hearts * texture_res) - 25, y = -(48 + texture_res + 16)}
+end
+
+minetest.register_on_joinplayer(function(player)
+	player:hud_set_flags({healthbar = false}) -- Hide the builtin HP bar
+	-- Add own HP bar with the same visuals as the builtin one
+	ids[player:get_player_name()] = player:hud_add({
+		hud_elem_type = "statbar",
+		position = {x = 0.5, y = 1},
+		text = "heart.png",
+		text2 = "heart_gone.png",
+		number = minetest.PLAYER_MAX_HP_DEFAULT,
+		item = minetest.PLAYER_MAX_HP_DEFAULT,
+		direction = 0,
+		size = {x = texture_res, y = texture_res},
+		offset = calculate_offset(10),
+	})
+end)
+
+minetest.register_on_leaveplayer(function(player)
+	ids[player:get_player_name()] = nil
+end)
+
+-- HACK `register_playerevent` is not documented, but used to implement statbars by MT internally
+minetest.register_playerevent(function(player, eventname)
+	if eventname == "health_changed" then
+		player:hud_change(ids[player:get_player_name()], "number", player:get_hp())
+	elseif eventname == "properties_changed" then
+		-- HP max has probably changed, update HP bar background size ("item") accordingly
+		local hp_max = player:get_properties().hp_max
+		local id = ids[player:get_player_name()]
+		player:hud_change(id, "item", hp_max)
+		player:hud_change(id, "offset", calculate_offset(hp_max / 2))
+	end
+end)

mods/other/hpbar_hud/mod.conf

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+name = hpbar_hud