diff --git a/src/lights/ibl/brdf.lisp b/src/lights/ibl/brdf.lisp
index bcf0944..7f7dab4 100644
--- a/src/lights/ibl/brdf.lisp
+++ b/src/lights/ibl/brdf.lisp
@@ -7,11 +7,6 @@
    (brdf-fbo :reader brdf-fbo))
   (:documentation "brdf lookup table"))
 
-(defmethod free :after ((obj brdf))
-  (free (bs obj))
-  (free (brdf-fbo obj))
-  (free (brdf-tex obj)))
-
 (defun-g importance-sample-ggx ((xi :vec2)
                                 (n :vec3)
                                 (roughness :float))
diff --git a/src/lights/lights.lisp b/src/lights/lights.lisp
index 7c63839..f48a6cb 100644
--- a/src/lights/lights.lisp
+++ b/src/lights/lights.lisp
@@ -24,21 +24,6 @@
    (point-ubo :reader point-ubo :documentation "common point lights ubo"))
   (:documentation "state global pointlight resources"))
 
-(defmethod free :after ((obj spotlights))
-  (with-slots (spot-tex spot-ubo) obj
-    (free spot-tex)
-    (free spot-ubo)))
-
-(defmethod free :after ((obj pointlights))
-  (with-slots (point-tex point-ubo) obj
-    (free point-tex)
-    (free point-ubo)))
-
-(defmethod free :after ((obj dirlights))
-  (with-slots (dir-tex dir-ubo) obj
-    (free dir-tex)
-    (free dir-ubo)))
-
 (defmethod initialize-instance :before ((obj lights) &key dim)
   (check-type dim (integer 256 4096)))
 
diff --git a/src/material/material.lisp b/src/material/material.lisp
index 4f6991c..f1209d6 100644
--- a/src/material/material.lisp
+++ b/src/material/material.lisp
@@ -60,3 +60,9 @@
       (setf (aref-c (pbr-material-specular     (aref-c c 0)) idx) specular)
       (setf (aref-c (pbr-material-metallic     (aref-c c 0)) idx) metallic)
       (setf (aref-c (pbr-material-emissive     (aref-c c 0)) idx) emissive))))
+
+(defun set-and-upload-materials (materials materials-ubo)
+  (mapc (lambda (m)
+          (setf (slot-value m 'ubo) materials-ubo)
+          (upload m))
+        materials))
diff --git a/src/screen.lisp b/src/screen.lisp
index 760dcb6..5b1f815 100644
--- a/src/screen.lisp
+++ b/src/screen.lisp
@@ -15,10 +15,6 @@
     (setf (slot-value obj 'prev) (make-renderable))
     (setf (slot-value obj 'next) (make-renderable))))
 
-(defmethod free :after ((obj screen))
-  (free (prev obj))
-  (free (next obj)))
-
 (defmethod handle :after ((e resize) (obj screen))
   (setf (dim (prev *state*)) (list (width e) (height e))
         (dim (next *state*)) (list (width e) (height e))))
diff --git a/src/state.lisp b/src/state.lisp
index 1a51e54..d31c3dd 100644
--- a/src/state.lisp
+++ b/src/state.lisp
@@ -18,16 +18,26 @@
 (defmethod initialize-instance :after ((obj state) &key materials)
   (with-slots (materials-ubo) obj
     (setf materials-ubo (make-ubo NIL 'pbr-material))
-    (mapc (lambda (m)
-            (setf (slot-value m 'ubo) materials-ubo)
-            (upload m))
-          materials)))
+    (set-and-upload-materials materials materials-ubo)))
+
+(defmethod reinitialize-instance :after ((obj state) &key materials)
+  (with-slots (scenes scene-index last-time materials-ubo) obj
+    (set-and-upload-materials materials materials-ubo)
+    (setf last-time (get-internal-real-time))
+    (setf scene-index -1)
+    (setf scenes ())))
 
 (defun init-state (materials)
-  (setf *state* (make-instance 'state :materials materials)))
+  (if *state*
+      (reinitialize-instance *state* :materials materials)
+      (setf *state* (make-instance 'state :materials materials))))
+
+(defun init-default-state ()
+  (init-state (list (make-material :roughness .8 :metallic .02 :specular .1)
+                    (make-material :roughness .4 :metallic .4  :specular .1))))
 
 (defmethod free ((obj state))
-  (free (materials-ubo obj))
+  (reset-material-counter)
   (mapc #'free (scenes obj)))
 
 (defmethod (setf scene-index) :before (new-value (obj state))
@@ -51,7 +61,3 @@
 (defmethod handle :around ((e resize) (obj perspective))
   (when (equal obj (current-camera))
     (call-next-method)))
-
-(defun init-default-state ()
-  (init-state (list (make-material :roughness .8 :metallic .02 :specular .1)
-                    (make-material :roughness .4 :metallic .4  :specular .1))))