add gc utils and bind them to f12

main.lua

@@ -53,7 +53,7 @@ function love.load()
             up = {'key:up', 'key:w'},
             down = {'key:down', 'key:s'},
             action = {'key:z', 'key:space'},
-            f1 = {'key:f1'}, f2 = {'key:f2'}, f3 = {'key:f3'}
+            f1 = {'key:f1'}, f2 = {'key:f2'}, f3 = {'key:f3'}, f12 = {'key:f12'}
         },
         pairs = {
             move = {'left', 'right', 'up', 'down'}
@@ -69,7 +69,16 @@ function love.update(dt)
     input:update(dt)
     if input:pressed('f1') then gotoRoom('CircleRoom') end
     if input:pressed('f3') then camera:shake(4, 60, 1) end
-
+    if input:pressed('f12') then
+        print("-------------------------------------")
+        print("Before collection: " .. collectgarbage("count")/1024)
+        collectgarbage()
+        print("After collection: " .. collectgarbage("count")/1024)
+        print("Object count: ")
+        local counts = type_count()
+        for k, v in pairs(counts) do print(k, v) end
+        print("-------------------------------------")
+    end
     camera:update(dt)
 end
 
@@ -121,6 +130,7 @@ function gotoRoom(room_type, ...)
     if type(Class) ~= "table" and type(Class) ~= "function" then
         error("room '"..room_type.."' is not callable (got "..type(Class)..", does room return itself?)")
     end
+    if current_room and current_room.destroy then current_room:destroy() end
     current_room = _G[room_type](...)
 end
 
@@ -150,3 +160,56 @@ function random(min, max)
     local min, max = min or 0, max or 1
     return (min > max and (love.math.random()*(min - max) + max)) or (love.math.random()*(max - min) + min)
 end
+
+------------------------
+-- garbage collection --
+------------------------
+
+---Counts all globals and applies function
+---@param f function
+function count_all(f)
+    local seen = {}
+    local count_table
+    count_table = function(t)
+        if seen[t] then return end
+            f(t)
+    seen[t] = true
+    for k,v in pairs(t) do
+        if type(v) == "table" then
+    count_table(v)
+        elseif type(v) == "userdata" then
+    f(v)
+        end
+end
+    end
+    count_table(_G)
+end
+
+---Count all types of globals
+---@return table
+function type_count()
+    local counts = {}
+    local enumerate = function (o)
+        local t = type_name(o)
+        counts[t] = (counts[t] or 0) + 1
+    end
+    count_all(enumerate)
+    return counts
+end
+
+global_type_table = nil
+---Resolves an object's true class name via metatable lookup.
+---Caches results in `global_type_table` for speed.
+---Fallbacks: "table" (no metatable), "Unknown" (uncached).
+---@param o any Any object (table, userdata, etc.)
+---@return string Class name (e.g., "Player", "Camera", "ImageData")
+function type_name(o)
+    if global_type_table == nil then
+        global_type_table = {}
+            for k,v in pairs(_G) do
+        global_type_table[v] = k
+    end
+global_type_table[0] = "table"
+    end
+    return global_type_table[getmetatable(o) or 0] or "Unknown"
+end

obj/Room.lua

@@ -46,4 +46,10 @@ function Room:canvasDraw()
     self.area:draw()
 end
 
+---Destroys room
+function Room:destroy()
+    self.area:destroy()
+    self.area = nil
+end
+
 return Room