diff --git a/src/r_things.cpp b/src/r_things.cpp
index b8d717be1..d65eb2a81 100644
--- a/src/r_things.cpp
+++ b/src/r_things.cpp
@@ -1659,13 +1659,6 @@ fixed_t R_GetSpriteDirectionalLighting(angle_t angle)
 	return extralight;
 }
 
-INT32 R_ThingLightLevel(mobj_t* thing)
-{
-	INT32 lightlevel = thing->lightlevel;
-
-	return lightlevel;
-}
-
 //
 // R_ProjectSprite
 // Generates a vissprite for a thing
diff --git a/src/r_things.h b/src/r_things.h
index c85b2c63d..69f0ec518 100644
--- a/src/r_things.h
+++ b/src/r_things.h
@@ -97,7 +97,10 @@ boolean R_ThingIsFlashing(mobj_t *thing);
 
 boolean R_ThingIsUsingBakedOffsets(mobj_t *thing);
 
-INT32 R_ThingLightLevel(mobj_t *thing);
+FUNCINLINE static ATTRINLINE INT32 R_ThingLightLevel(mobj_t* thing)
+{
+	return (INT32)thing->lightlevel;
+}
 
 // --------------
 // MASKED DRAWING
@@ -110,7 +113,7 @@ struct maskcount_t
 {
 	size_t drawsegs[2];
 	size_t vissprites[2];
-	fixed_t viewx, viewy, viewz;			/**< View z stored at the time of the BSP traversal for the view/portal. Masked sorting/drawing needs it. */
+	fixed_t viewx, viewy, viewz; /**< View z stored at the time of the BSP traversal for the view/portal. Masked sorting/drawing needs it. */
 	sector_t* viewsector;
 };