diff --git a/src/hardware/hw_main.c b/src/hardware/hw_main.c
index fbc8e7547..3fecba478 100644
--- a/src/hardware/hw_main.c
+++ b/src/hardware/hw_main.c
@@ -3733,7 +3733,7 @@ static void HWR_RotateSpritePolyToAim(gl_vissprite_t *spr, FOutVector *wallVerts
 		{
 			if (spr->precip)
 			{
-				R_InterpolatePrecipMobjState(spr->mobj, rendertimefrac, &interp);
+				R_InterpolatePrecipMobjState((precipmobj_t *)spr->mobj, rendertimefrac, &interp);
 			}
 			else
 			{
@@ -3744,7 +3744,7 @@ static void HWR_RotateSpritePolyToAim(gl_vissprite_t *spr, FOutVector *wallVerts
 		{
 			if (spr->precip)
 			{
-				R_InterpolatePrecipMobjState(spr->mobj, FRACUNIT, &interp);
+				R_InterpolatePrecipMobjState((precipmobj_t *)spr->mobj, FRACUNIT, &interp);
 			}
 			else
 			{