diff --git a/common/main/lighting.h b/common/main/lighting.h
index 747b04219..80813c300 100644
--- a/common/main/lighting.h
+++ b/common/main/lighting.h
@@ -45,7 +45,7 @@ extern object *old_viewer;
 // compute the lighting for an object.  Takes a pointer to the object,
 // and possibly a rotated 3d point.  If the point isn't specified, the
 // object's center point is rotated.
-g3s_lrgb compute_object_light(vobjptridx_t obj,const vms_vector *rotated_pnt);
+g3s_lrgb compute_object_light(vcobjptridx_t obj, const vms_vector *rotated_pnt);
 
 // turn headlight boost on & off
 void toggle_headlight_active(void);
diff --git a/similar/main/lighting.cpp b/similar/main/lighting.cpp
index cc508d699..c766575f7 100644
--- a/similar/main/lighting.cpp
+++ b/similar/main/lighting.cpp
@@ -614,7 +614,7 @@ void start_lighting_frame(const vobjptr_t viewer)
 //compute the lighting for an object.  Takes a pointer to the object,
 //and possibly a rotated 3d point.  If the point isn't specified, the
 //object's center point is rotated.
-g3s_lrgb compute_object_light(const vobjptridx_t obj,const vms_vector *rotated_pnt)
+g3s_lrgb compute_object_light(const vcobjptridx_t obj, const vms_vector *rotated_pnt)
 {
 	g3s_lrgb light, seg_dl;
 	fix mlight;