diff --git a/polymer/eduke32/source/actors.c b/polymer/eduke32/source/actors.c
index 7956fe0bd..d7d7e5d9e 100644
--- a/polymer/eduke32/source/actors.c
+++ b/polymer/eduke32/source/actors.c
@@ -632,12 +632,12 @@ void Sect_ClearInterpolation(int32_t sectnum)
     }
 }
 
-static int32_t move_fixed_sprite(int32_t j, int32_t pivotspr, int32_t daang)
+static int32_t move_rotfixed_sprite(int32_t j, int32_t pivotspr, int32_t daang)
 {
-    if ((FIXSPR_STATNUMP(sprite[j].statnum) ||
+    if ((ROTFIXSPR_STATNUMP(sprite[j].statnum) ||
          ((sprite[j].statnum==STAT_ACTOR || sprite[j].statnum==STAT_ZOMBIEACTOR) &&
-         A_CheckSpriteTileFlags(sprite[j].picnum, SPRITE_BADGUY)))
-            && actor[j].t_data[7]==(0x18190000|pivotspr))
+          A_CheckSpriteTileFlags(sprite[j].picnum, SPRITE_ROTFIXED)))
+        && actor[j].t_data[7]==(ROTFIXSPR_MAGIC|pivotspr))
     {
         rotatepoint(0,0, actor[j].t_data[8],actor[j].t_data[9], daang&2047, &sprite[j].x,&sprite[j].y);
         sprite[j].x += sprite[pivotspr].x;
@@ -1440,7 +1440,7 @@ ACTOR_STATIC void G_MoveStandables(void)
             KILLIT(i);
 
         // 'fixed' sprites in rotating sectors already have bpos* updated
-        if ((t[7]&(0xffff0000))!=0x18190000)
+        if ((t[7]&(0xffff0000))!=ROTFIXSPR_MAGIC)
             Bmemcpy(&actor[i].bpos.x, s, sizeof(vec3_t));
 
         IFWITHIN(CRANE,CRANE+3)
@@ -5685,7 +5685,7 @@ ACTOR_STATIC void G_MoveEffectors(void)   //STATNUM 3
                             actor[p].bpos.x = sprite[p].x;
                             actor[p].bpos.y = sprite[p].y;
 
-                            if (move_fixed_sprite(p, j, t[2]))
+                            if (move_rotfixed_sprite(p, j, t[2]))
                                 rotatepoint(sprite[j].x,sprite[j].y,sprite[p].x,sprite[p].y,(q*l),&sprite[p].x,&sprite[p].y);
                         }
                 }
@@ -5913,7 +5913,7 @@ ACTOR_STATIC void G_MoveEffectors(void)   //STATNUM 3
                             actor[j].bpos.y = sprite[j].y;
                         }
 
-                        if (move_fixed_sprite(j, s-sprite, t[2]))
+                        if (move_rotfixed_sprite(j, s-sprite, t[2]))
                             rotatepoint(s->x,s->y,sprite[j].x,sprite[j].y,q,&sprite[j].x,&sprite[j].y);
 
                         sprite[j].x+= m;
diff --git a/polymer/eduke32/source/actors.h b/polymer/eduke32/source/actors.h
index 1956a6ef4..b8fffa13d 100644
--- a/polymer/eduke32/source/actors.h
+++ b/polymer/eduke32/source/actors.h
@@ -209,6 +209,9 @@ enum sflags_t {
     SPRITE_NOTELEPORT       = 0x00004000,
     SPRITE_BADGUYSTAYPUT    = 0x00008000,
     SPRITE_CACHE            = 0x00010000,
+    // rotation-fixed wrt a pivot point to prevent position diverging due to
+    // roundoff error accumulation:
+    SPRITE_ROTFIXED         = 0x00020000,
 };
 
 // custom projectiles
diff --git a/polymer/eduke32/source/duke3d.h b/polymer/eduke32/source/duke3d.h
index 96b1ec8a6..c81662135 100644
--- a/polymer/eduke32/source/duke3d.h
+++ b/polymer/eduke32/source/duke3d.h
@@ -98,8 +98,9 @@ Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 #define TILE_VIEWSCR        (MAXTILES-5)
 
 // sprites with these statnums should be considered for fixing (bitmap)
-#define FIXSPR_STATNUMP(k) ((k)==STAT_DEFAULT || (k)==STAT_STANDABLE || (k)==STAT_FX || \
+#define ROTFIXSPR_STATNUMP(k) ((k)==STAT_DEFAULT || (k)==STAT_STANDABLE || (k)==STAT_FX || \
                             (k)==STAT_FALLER || (k)==STAT_LIGHT)
+#define ROTFIXSPR_MAGIC 0x18190000
 
 // JBF 20040604: sync is a function on some platforms
 #define sync                dsync
diff --git a/polymer/eduke32/source/gamedef.c b/polymer/eduke32/source/gamedef.c
index 0d2cccbc9..faacc7dae 100644
--- a/polymer/eduke32/source/gamedef.c
+++ b/polymer/eduke32/source/gamedef.c
@@ -2771,6 +2771,9 @@ static int32_t C_ParseCommand(int32_t loop)
 
                 if (j & 2)
                     g_tile[*g_scriptPtr].flags |= (SPRITE_BADGUY|SPRITE_BADGUYSTAYPUT);
+
+                if (j & 4)
+                    g_tile[*g_scriptPtr].flags |= SPRITE_ROTFIXED;
             }
 
             for (j=0; j<4; j++)
diff --git a/polymer/eduke32/source/premap.c b/polymer/eduke32/source/premap.c
index 95e72a797..b4ce013a3 100644
--- a/polymer/eduke32/source/premap.c
+++ b/polymer/eduke32/source/premap.c
@@ -1003,9 +1003,9 @@ static void premap_setup_fixed_sprites(void)
             {
                 // TRIPBOMB uses t_data[7] for its own purposes. Wouldn't be
                 // too useful with moving sectors anyway
-                if ((FIXSPR_STATNUMP(sprite[j].statnum) && sprite[j].picnum!=TRIPBOMB) ||
+                if ((ROTFIXSPR_STATNUMP(sprite[j].statnum) && sprite[j].picnum!=TRIPBOMB) ||
                     ((sprite[j].statnum==STAT_ACTOR || sprite[j].statnum==STAT_ZOMBIEACTOR) &&
-                    A_CheckSpriteTileFlags(sprite[j].picnum, SPRITE_BADGUY)))
+                     A_CheckSpriteTileFlags(sprite[j].picnum, SPRITE_ROTFIXED)))
                 {
                     pivot = i;
                     if (sprite[i].lotag==0)
@@ -1013,7 +1013,7 @@ static void premap_setup_fixed_sprites(void)
                     if (j!=i && j!=pivot && pivot>=0 && pivot<MAXSPRITES)
                     {
                         // let's hope we don't step on anyone's toes here
-                        actor[j].t_data[7] = 0x18190000 | pivot; // 'rs' magic + pivot SE sprite index
+                        actor[j].t_data[7] = ROTFIXSPR_MAGIC | pivot; // 'rs' magic + pivot SE sprite index
                         actor[j].t_data[8] = sprite[j].x - sprite[pivot].x;
                         actor[j].t_data[9] = sprite[j].y - sprite[pivot].y;
                     }