diff --git a/include/ak/transform.h b/include/ak/transform.h
index e12bf188..0d723737 100644
--- a/include/ak/transform.h
+++ b/include/ak/transform.h
@@ -81,13 +81,13 @@ ak_transformSkewMatrix(AkSkew * __restrict skew,
  *
  * if there is no transform then this returns identity matrix
  *
- * @param node   node
- * @param matrix combined transform (must be aligned 16)
+ * @param transform transform
+ * @param matrix    combined transform (must be aligned 16)
  */
 AK_EXPORT
 void
-ak_transformCombine(AkNode * __restrict node,
-                    float  * matrix);
+ak_transformCombine(AkTransform * __restrict transform,
+                    float       * __restrict matrix);
 
 /*!
  * @brief combines all node's transform elements in **world coord sys**
diff --git a/src/bbox/scene.c b/src/bbox/scene.c
index e56f3ebd..302d44d6 100644
--- a/src/bbox/scene.c
+++ b/src/bbox/scene.c
@@ -45,7 +45,7 @@ ak_bbox_node(AkHeap        * __restrict heap,
 
   matrixWorld = node->matrixWorld->val;
 
-  ak_transformCombine(node, node->matrix->val[0]);
+  ak_transformCombine(node->transform, node->matrix->val[0]);
   glm_mat4_mul(parentTrans, node->matrix->val, matrixWorld);
 
   if (node->geometry) {
diff --git a/src/common.h b/src/common.h
index ba732a58..4993faf0 100644
--- a/src/common.h
+++ b/src/common.h
@@ -24,6 +24,7 @@
 #include "../include/ak/map.h"
 #include "../include/ak/type.h"
 #include "../include/ak/url.h"
+#include "../include/ak/transform.h"
 
 #include "mem/common.h"
 
diff --git a/src/transform/trans.c b/src/transform/trans.c
index 5300e251..60e4371c 100644
--- a/src/transform/trans.c
+++ b/src/transform/trans.c
@@ -55,31 +55,31 @@ ak_transformSkewMatrix(AkSkew * __restrict skew,
 
 AK_EXPORT
 void
-ak_transformCombine(AkNode * __restrict node,
-                    float  * matrix) {
-  AkObject *transform, *transformGroup;
+ak_transformCombine(AkTransform * __restrict transform,
+                    float       * __restrict matrix) {
+  AkObject *transformItem, *transformGroup;
   mat4      mat = GLM_MAT4_IDENTITY_INIT;
   mat4      tmp;
 
-  if (!node->transform)
+  if (!transform || !matrix)
     goto ret;
 
-  transformGroup = node->transform->base;
+  transformGroup = transform->base;
 
 again:
-  transform = transformGroup;
-  while (transform) {
-    switch (transform->type) {
+  transformItem = transformGroup;
+  while (transformItem) {
+    switch (transformItem->type) {
       case AKT_MATRIX: {
         AkMatrix *matrix;
-        matrix = ak_objGet(transform);
+        matrix = ak_objGet(transformItem);
 
         glm_mat4_mul(mat, matrix->val, mat);
         break;
       }
       case AKT_LOOKAT: {
         AkLookAt *lookAt;
-        lookAt = ak_objGet(transform);
+        lookAt = ak_objGet(transformItem);
 
         glm_lookat(lookAt->val[0],
                    lookAt->val[1],
@@ -94,7 +94,7 @@ ak_transformCombine(AkNode * __restrict node,
       case AKT_ROTATE: {
         AkRotate *rotate;
 
-        rotate = ak_objGet(transform);
+        rotate = ak_objGet(transformItem);
         glm_rotate_make(tmp, rotate->val[3], rotate->val);
         glm_mat4_mul(mat, tmp, mat);
         break;
@@ -102,14 +102,14 @@ ak_transformCombine(AkNode * __restrict node,
       case AKT_QUATERNION: {
         AkQuaternion *quat;
 
-        quat = ak_objGet(transform);
+        quat = ak_objGet(transformItem);
         glm_quat_mat4(quat->val, tmp);
         glm_mat4_mul(mat, tmp, mat);
         break;
       }
       case AKT_SCALE: {
         AkScale *scale;
-        scale = ak_objGet(transform);
+        scale = ak_objGet(transformItem);
 
         glm_scale_make(tmp, scale->val);
         glm_mat4_mul(mat, tmp, mat);
@@ -117,7 +117,7 @@ ak_transformCombine(AkNode * __restrict node,
       }
       case AKT_TRANSLATE: {
         AkTranslate *translate;
-        translate = ak_objGet(transform);
+        translate = ak_objGet(transformItem);
 
         glm_translate_make(tmp, translate->val);
         glm_mat4_mul(mat, tmp, mat);
@@ -125,7 +125,7 @@ ak_transformCombine(AkNode * __restrict node,
       }
       case AKT_SKEW: {
         AkSkew *skew;
-        skew = ak_objGet(transform);
+        skew = ak_objGet(transformItem);
 
         ak_transformSkewMatrix(skew, tmp[0]);
         glm_mat4_mul(mat, tmp, mat);
@@ -133,11 +133,11 @@ ak_transformCombine(AkNode * __restrict node,
       }
     }
 
-    transform = transform->next;
+    transformItem = transformItem->next;
   }
 
-  if (transformGroup != node->transform->item) {
-    transformGroup = node->transform->item;
+  if (transformGroup != transform->item) {
+    transformGroup = transform->item;
     goto again;
   }
 
diff --git a/src/transform/traverse.c b/src/transform/traverse.c
index 79996037..5a542557 100644
--- a/src/transform/traverse.c
+++ b/src/transform/traverse.c
@@ -25,11 +25,11 @@ ak_transformCombineWorld(AkNode * __restrict node,
   mat4    mat;
   mat4    ptrans;
 
-  ak_transformCombine(node, mat[0]);
+  ak_transformCombine(node->transform, mat[0]);
 
   parentNode = node->parent;
   while (parentNode) {
-    ak_transformCombine(parentNode, ptrans[0]);
+    ak_transformCombine(parentNode->transform, ptrans[0]);
 
     glm_mat4_mul(ptrans, mat, mat);
     parentNode = parentNode->parent;