diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..600d2d3
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1 @@
+.vscode
\ No newline at end of file
diff --git a/lib/math2.lua b/lib/math2.lua
index d3e858b..6cc5f27 100644
--- a/lib/math2.lua
+++ b/lib/math2.lua
@@ -25,3 +25,7 @@ end
 math.step_floor = function(n, step)
     return math.floor(n / step) * step
 end
+
+math.step_ceil = function(n, step)
+    return math.ceil(n / step) * step
+end
\ No newline at end of file
diff --git a/lib/spatial_grid.lua b/lib/spatial_grid.lua
index 6b94a73..a0e507d 100644
--- a/lib/spatial_grid.lua
+++ b/lib/spatial_grid.lua
@@ -4,16 +4,17 @@ require "lib.entity"
 require "math"
 
 local __SpatialGrid = {
-    table = {}
+    table = {},
+    cell_size = 0
 }
 
----- uncomment this for test
+-- uncomment this for test
 -- __Entity = {
 --     position = Vec3 {},
 --     some_other_shit = "this litteraly other shit"
 -- }
 
--- function Entity(pos)
+-- local function Entity(pos)
 --     local entity = {
 --         position = pos
 --     }
@@ -21,49 +22,77 @@ local __SpatialGrid = {
 --     return setmetatable(entity, {__index = __Entity})
 -- end
 
+local function str_position(x, y)
+    return tostring(x) .. " " .. tostring(y)
+end
 
 function SpatialGrid(center, side, cell_size, entities)
     local lu_side = Vec3 {center.x - math.ceil(side/2), center.y - math.ceil(side/2)}
     local rd_side = Vec3 {center.x + math.floor(side/2), center.y + math.floor(side/2)}
 
-    local pos_entities = {}
+    local pos_entities = {}  -- таблица, где ключ это позиция объекта, а значение это сам объект
     for _, entity in ipairs(entities) do
-        local pos = tostring(math.step_floor(entity.position.x, cell_size)) .. " " .. tostring(math.step_floor(entity.position.y, cell_size))
+        local pos = str_position(math.step_floor(entity.position.x, cell_size), math.step_floor(entity.position.y, cell_size))
         if pos_entities[pos] == nil then
             pos_entities[pos] = {}
         end
         table.insert(pos_entities[pos], entity)
     end
 
-    table = {}
+    local table = {}
     for x = lu_side.x, rd_side.x, cell_size do
         for y = lu_side.y, rd_side.y, cell_size do
-            local pos = tostring(x) .. " " .. tostring(y)
-            table[pos] = {position = Vec3 {x, y}, content = pos_entities[pos]}
+            local pos = str_position(x, y)
+            table[pos] = {position = Vec3 {x, y}, content = pos_entities[pos]}  -- содержимое таблицы table в таблице spatialgrid
         end
     end
 
-    return setmetatable({table = table}, {__index = __SpatialGrid})  -- честно не уверен зачем это, но пусть будет
+    return setmetatable({table = table, cell_size = cell_size}, {__index = __SpatialGrid})  -- честно не уверен зачем это, но пусть будет
 end
 
 function __SpatialGrid:query(position)
     local entities = {}
     for extra_x = -1, 1 do
         for extra_y = -1, 1 do
-            local entity_pos = tostring(position.x + extra_x) .. " " .. tostring(position.y + extra_y)
+            local entity_pos = str_position(position.x + extra_x*self.cell_size, position.y + extra_y*self.cell_size)
             entities[entity_pos] = self.table[entity_pos].content
         end
     end
     return entities
 end
 
----- uncomment this too for test
--- local table = SpatialGrid(Vec3 {0, 0}, 10, 0.5, {Entity(Vec3 {-1, -1, 0}), Entity(Vec3 {-1.5, -1, 0}), Entity(Vec3 {-2, -1, 0})})
+function __SpatialGrid:add(obj)
+    local obj_x, obj_y = 0, 0
 
--- local query_table = table:query(Vec3 {-1, -1, 0})
+    if obj.position.x > 0 then
+        obj_x = math.step_floor(obj.position.x, self.cell_size)
+    else
+        obj_x = math.step_ceil(obj.position.x, self.cell_size)
+    end
+
+    if obj.position.y > 0 then
+        obj_y = math.step_floor(obj.position.y, self.cell_size)
+    else
+        obj_y = math.step_ceil(obj.position.y, self.cell_size)
+    end
+
+    local pos = str_position(obj_x, obj_y)
+    table.insert(self.table[pos].content, obj)
+end
+
+-- uncomment this too for test
+-- local my_table = SpatialGrid(Vec3 {0, 0}, 10, 0.5, {Entity(Vec3 {-1, -1, 0}), Entity(Vec3 {-1.5, -1, 0}), Entity(Vec3 {-2, -1, 0})})
+
+-- my_table:add(Entity(Vec3 {-1.25, -1, 0}))
+
+-- local query_table = my_table:query(Vec3 {-1, -1, 0})
 
 -- for k, v in pairs(query_table) do
 --     for i = 1, #v do
---         print(v[i].some_other_shit, v[i].position.y)
+--         print(v[i].some_other_shit, v[i].position.x)
 --     end
 -- end
+
+-- for i, v in ipairs(my_table.table["-1 -1"].content) do
+--     print(i, v)
+-- end