diff --git a/i-mic-fps.rb b/i-mic-fps.rb
index d8b3e16..199d95a 100644
--- a/i-mic-fps.rb
+++ b/i-mic-fps.rb
@@ -70,6 +70,7 @@ require_relative "lib/managers/entity_manager"
 require_relative "lib/managers/light_manager"
 require_relative "lib/managers/network_manager"
 require_relative "lib/managers/collision_manager"
+require_relative "lib/managers/physics_manager"
 
 require_relative "lib/renderer/renderer"
 require_relative "lib/renderer/shader"
diff --git a/lib/managers/collision_manager.rb b/lib/managers/collision_manager.rb
index 9ecbb30..c4a3e50 100644
--- a/lib/managers/collision_manager.rb
+++ b/lib/managers/collision_manager.rb
@@ -1,8 +1,12 @@
 class IMICFPS
   class CollisionManager
+    attr_reader :game_state, :collisions
     def initialize(game_state:)
       @game_state = game_state
-      @aabb_tree  = AABBTree.new
+      @collisions = {}
+
+      @aabb_tree       = AABBTree.new
+      @physics_manager = PhysicsManager.new(collision_manager: self)
     end
 
     def add(entity)
@@ -12,6 +16,7 @@ class IMICFPS
     def update
       lazy_check_collisions
       @aabb_tree.update
+      @physics_manager.update
     end
 
     def remove(entity)
diff --git a/lib/managers/physics_manager.rb b/lib/managers/physics_manager.rb
index b677d1d..9f3f92d 100644
--- a/lib/managers/physics_manager.rb
+++ b/lib/managers/physics_manager.rb
@@ -1,4 +1,18 @@
 class IMICFPS
   class PhysicsManager
+    def initialize(collision_manager:)
+      @collision_manager = collision_manager
+    end
+
+    def update
+      @collision_manager.collisions.each do |entity, versus|
+        versus.each do |versus|
+          resolve(entity, other)
+        end
+      end
+    end
+
+    def resolve(entity, other)
+    end
   end
 end
\ No newline at end of file
diff --git a/lib/math/bounding_box.rb b/lib/math/bounding_box.rb
index 27e4d42..955b87a 100644
--- a/lib/math/bounding_box.rb
+++ b/lib/math/bounding_box.rb
@@ -1,56 +1,42 @@
 class IMICFPS
   class BoundingBox
-    attr_accessor :min_x, :min_y, :min_z, :max_x, :max_y, :max_z
+    attr_accessor :min, :max
 
-    def initialize(min_x = 0.0, min_y = 0.0, min_z = 0.0, max_x = 0.0, max_y = 0.0, max_z = 0.0)
-      @min_x = min_x
-      @min_y = min_y
-      @min_z = min_z
-
-      @max_x = max_x
-      @max_y = max_y
-      @max_z = max_z
+    def initialize
+      @min = Vector.new
+      @max = Vector.new
     end
 
     def ==(other)
-      min_x == other.min_x &&
-      min_y == other.min_y &&
-      min_z == other.min_z &&
-      max_x == other.max_x &&
-      max_y == other.max_y &&
-      max_z == other.max_z
+      @min == other.min &&
+      @max == other.max
     end
 
     # returns a new bounding box that includes both bounding boxes
     def union(other)
       temp = BoundingBox.new
-      temp.min_x = [min_x, other.min_x].min
-      temp.min_y = [min_y, other.min_y].min
-      temp.min_z = [min_z, other.min_z].min
+      temp.min.x = [@min.x, other.min.x].min
+      temp.min.y = [@min.y, other.min.y].min
+      temp.min.z = [@min.z, other.min.z].min
 
-      temp.max_x = [max_x, other.max_x].max
-      temp.max_y = [max_y, other.max_y].max
-      temp.max_z = [max_z, other.max_z].max
+      temp.max.x = [@max.x, other.max.x].max
+      temp.max.y = [@max.y, other.max.y].max
+      temp.max.z = [@max.z, other.max.z].max
 
       return temp
     end
 
     # returns boolean
     def intersect(other)
-      (min_x <= other.max_x && max_x >= other.min_x) &&
-      (min_y <= other.max_y && max_y >= other.min_y) &&
-      (min_z <= other.max_z && max_z >= other.min_z)
+      (@min.x <= other.max.x && @max.x >= other.min.x) &&
+      (@min.y <= other.max.y && @max.y >= other.min.y) &&
+      (@min.z <= other.max.z && @max.z >= other.min.z)
     end
 
     def difference(other)
       temp = BoundingBox.new
-      temp.min_x = min_x - other.min_x
-      temp.min_y = min_y - other.min_y
-      temp.min_z = min_z - other.min_z
-
-      temp.max_x = max_x - other.max_x
-      temp.max_y = max_y - other.max_y
-      temp.max_z = max_z - other.max_z
+      temp.min = @min - other.min
+      temp.max = @max - other.max
 
       return temp
     end
@@ -60,39 +46,39 @@ class IMICFPS
     end
 
     def width
-      @max_x - @min_x
+      @max.x - @min.x
     end
 
     def height
-      @max_y - @min_y
+      @max.y - @min.y
     end
 
     def depth
-      @max_z - @min_z
+      @max.z - @min.z
     end
 
     def normalize(entity)
       temp = BoundingBox.new
-      temp.min_x = min_x.to_f * entity.scale
-      temp.min_y = min_y.to_f * entity.scale
-      temp.min_z = min_z.to_f * entity.scale
+      temp.min.x = @min.x.to_f * entity.scale
+      temp.min.y = @min.y.to_f * entity.scale
+      temp.min.z = @min.z.to_f * entity.scale
 
-      temp.max_x = max_x.to_f * entity.scale
-      temp.max_y = max_y.to_f * entity.scale
-      temp.max_z = max_z.to_f * entity.scale
+      temp.max.x = @max.x.to_f * entity.scale
+      temp.max.y = @max.y.to_f * entity.scale
+      temp.max.z = @max.z.to_f * entity.scale
 
       return temp
     end
 
     def normalize_with_offset(entity)
       temp = BoundingBox.new
-      temp.min_x = min_x.to_f * entity.scale + entity.position.x
-      temp.min_y = min_y.to_f * entity.scale + entity.position.y
-      temp.min_z = min_z.to_f * entity.scale + entity.position.z
+      temp.min.x = @min.x.to_f * entity.scale + entity.position.x
+      temp.min.y = @min.y.to_f * entity.scale + entity.position.y
+      temp.min.z = @min.z.to_f * entity.scale + entity.position.z
 
-      temp.max_x = max_x.to_f * entity.scale + entity.position.x
-      temp.max_y = max_y.to_f * entity.scale + entity.position.y
-      temp.max_z = max_z.to_f * entity.scale + entity.position.z
+      temp.max.x = @max.x.to_f * entity.scale + entity.position.x
+      temp.max.y = @max.y.to_f * entity.scale + entity.position.y
+      temp.max.z = @max.z.to_f * entity.scale + entity.position.z
 
       return temp
     end
diff --git a/lib/renderer/bounding_box_renderer.rb b/lib/renderer/bounding_box_renderer.rb
index e97f6a1..438bad1 100644
--- a/lib/renderer/bounding_box_renderer.rb
+++ b/lib/renderer/bounding_box_renderer.rb
@@ -157,53 +157,53 @@ class IMICFPS
 
     def mesh_vertices(box)
       [
-        box.min_x, box.max_y, box.max_z,
-        box.min_x, box.max_y, box.min_z,
-        box.max_x, box.max_y, box.min_z,
+        box.min.x, box.max.y, box.max.z,
+        box.min.x, box.max.y, box.min.z,
+        box.max.x, box.max.y, box.min.z,
 
-        box.min_x, box.max_y, box.max_z,
-        box.max_x, box.max_y, box.max_z,
-        box.max_x, box.max_y, box.min_z,
+        box.min.x, box.max.y, box.max.z,
+        box.max.x, box.max.y, box.max.z,
+        box.max.x, box.max.y, box.min.z,
 
-        box.max_x, box.min_y, box.min_z,
-        box.max_x, box.min_y, box.max_z,
-        box.min_x, box.min_y, box.max_z,
+        box.max.x, box.min.y, box.min.z,
+        box.max.x, box.min.y, box.max.z,
+        box.min.x, box.min.y, box.max.z,
 
-        box.max_x, box.min_y, box.min_z,
-        box.min_x, box.min_y, box.min_z,
-        box.min_x, box.min_y, box.max_z,
+        box.max.x, box.min.y, box.min.z,
+        box.min.x, box.min.y, box.min.z,
+        box.min.x, box.min.y, box.max.z,
 
-        box.min_x, box.max_y, box.max_z,
-        box.min_x, box.max_y, box.min_z,
-        box.min_x, box.min_y, box.min_z,
+        box.min.x, box.max.y, box.max.z,
+        box.min.x, box.max.y, box.min.z,
+        box.min.x, box.min.y, box.min.z,
 
-        box.min_x, box.min_y, box.max_z,
-        box.min_x, box.min_y, box.min_z,
-        box.min_x, box.max_y, box.max_z,
+        box.min.x, box.min.y, box.max.z,
+        box.min.x, box.min.y, box.min.z,
+        box.min.x, box.max.y, box.max.z,
 
-        box.max_x, box.max_y, box.max_z,
-        box.max_x, box.max_y, box.min_z,
-        box.max_x, box.min_y, box.min_z,
+        box.max.x, box.max.y, box.max.z,
+        box.max.x, box.max.y, box.min.z,
+        box.max.x, box.min.y, box.min.z,
 
-        box.max_x, box.min_y, box.max_z,
-        box.max_x, box.min_y, box.min_z,
-        box.max_x, box.max_y, box.max_z,
+        box.max.x, box.min.y, box.max.z,
+        box.max.x, box.min.y, box.min.z,
+        box.max.x, box.max.y, box.max.z,
 
-        box.min_x, box.max_y, box.max_z,
-        box.max_x, box.max_y, box.max_z,
-        box.max_x, box.min_y, box.max_z,
+        box.min.x, box.max.y, box.max.z,
+        box.max.x, box.max.y, box.max.z,
+        box.max.x, box.min.y, box.max.z,
 
-        box.min_x, box.max_y, box.max_z,
-        box.max_x, box.min_y, box.max_z,
-        box.min_x, box.min_y, box.max_z,
+        box.min.x, box.max.y, box.max.z,
+        box.max.x, box.min.y, box.max.z,
+        box.min.x, box.min.y, box.max.z,
 
-        box.max_x, box.min_y, box.min_z,
-        box.min_x, box.min_y, box.min_z,
-        box.min_x, box.max_y, box.min_z,
+        box.max.x, box.min.y, box.min.z,
+        box.min.x, box.min.y, box.min.z,
+        box.min.x, box.max.y, box.min.z,
 
-        box.max_x, box.min_y, box.min_z,
-        box.min_x, box.max_y, box.min_z,
-        box.max_x, box.max_y, box.min_z
+        box.max.x, box.min.y, box.min.z,
+        box.min.x, box.max.y, box.min.z,
+        box.max.x, box.max.y, box.min.z
       ]
     end
 
diff --git a/lib/trees/aabb_tree.rb b/lib/trees/aabb_tree.rb
index ef907b8..192f26c 100644
--- a/lib/trees/aabb_tree.rb
+++ b/lib/trees/aabb_tree.rb
@@ -12,7 +12,7 @@ class IMICFPS
       if @root
         @root.insert_subtree(bounding_box.dup, object)
       else
-        @root = AABBNode.new(parent: nil, object: object, bounding_box: BoundingBox.new(0,0,0, 0,0,0))
+        @root = AABBNode.new(parent: nil, object: object, bounding_box: BoundingBox.new)
       end
     end
 
@@ -48,6 +48,15 @@ class IMICFPS
         @b = nil
       end
 
+      def make_leaf
+        @a = nil
+        @b = nil
+      end
+
+      def make_branch(node_a, node_b)
+
+      end
+
       def insert_subtree(bounding_box, object)
         # p "#{bounding_box} -> #{object.class}"
       end
diff --git a/lib/wavefront/model.rb b/lib/wavefront/model.rb
index 863adff..668a880 100644
--- a/lib/wavefront/model.rb
+++ b/lib/wavefront/model.rb
@@ -35,7 +35,7 @@ class IMICFPS
         @faces    = []
         @smoothing= 0
 
-        @bounding_box = BoundingBox.new(0,0,0, 0,0,0)
+        @bounding_box = BoundingBox.new
         start_time = Process.clock_gettime(Process::CLOCK_MONOTONIC, :float_millisecond)
 
         parse
diff --git a/lib/wavefront/object.rb b/lib/wavefront/object.rb
index 6837377..4d922e9 100644
--- a/lib/wavefront/object.rb
+++ b/lib/wavefront/object.rb
@@ -10,7 +10,7 @@ class IMICFPS
         @textures = []
         @normals  = []
         @faces    = []
-        @bounding_box = BoundingBox.new(0,0,0, 0,0,0)
+        @bounding_box = BoundingBox.new
         @debug_color = Color.new(1.0,1.0,1.0)
 
         @scale = 1.0
diff --git a/lib/wavefront/parser.rb b/lib/wavefront/parser.rb
index c2f3386..dbf0811 100644
--- a/lib/wavefront/parser.rb
+++ b/lib/wavefront/parser.rb
@@ -151,25 +151,25 @@ class IMICFPS
       end
 
       def calculate_bounding_box(vertices, bounding_box)
-        unless bounding_box.min_x.is_a?(Float)
+        unless bounding_box.min.x.is_a?(Float)
           vertex = vertices.last
-          bounding_box.min_x = vertex.x
-          bounding_box.min_y = vertex.y
-          bounding_box.min_z = vertex.z
+          bounding_box.min.x = vertex.x
+          bounding_box.min.y = vertex.y
+          bounding_box.min.z = vertex.z
 
-          bounding_box.max_x = vertex.x
-          bounding_box.max_y = vertex.y
-          bounding_box.max_z = vertex.z
+          bounding_box.max.x = vertex.x
+          bounding_box.max.y = vertex.y
+          bounding_box.max.z = vertex.z
         end
 
         vertices.each do |vertex|
-          bounding_box.min_x = vertex.x if vertex.x <= bounding_box.min_x
-          bounding_box.min_y = vertex.y if vertex.y <= bounding_box.min_y
-          bounding_box.min_z = vertex.z if vertex.z <= bounding_box.min_z
+          bounding_box.min.x = vertex.x if vertex.x <= bounding_box.min.x
+          bounding_box.min.y = vertex.y if vertex.y <= bounding_box.min.y
+          bounding_box.min.z = vertex.z if vertex.z <= bounding_box.min.z
 
-          bounding_box.max_x = vertex.x if vertex.x >= bounding_box.max_x
-          bounding_box.max_y = vertex.y if vertex.y >= bounding_box.max_y
-          bounding_box.max_z = vertex.z if vertex.z >= bounding_box.max_z
+          bounding_box.max.x = vertex.x if vertex.x >= bounding_box.max.x
+          bounding_box.max.y = vertex.y if vertex.y >= bounding_box.max.y
+          bounding_box.max.z = vertex.z if vertex.z >= bounding_box.max.z
         end
       end
     end