diff --git a/polymer/eduke32/build/include/build.h b/polymer/eduke32/build/include/build.h
index 84b4b6d40..0547a262b 100644
--- a/polymer/eduke32/build/include/build.h
+++ b/polymer/eduke32/build/include/build.h
@@ -774,6 +774,17 @@ EXTERN psky_t multipsky[MAXPSKYMULTIS];
 // Mapping of multi-sky index to base sky tile number:
 EXTERN int32_t multipskytile[MAXPSKYMULTIS];
 
+static inline int32_t getpskyidx(int32_t picnum)
+{
+    int32_t j;
+
+    for (j=pskynummultis; j>0; j--)  // NOTE: j==0 on non-early loop end
+        if (picnum == multipskytile[j])
+            break;  // Have a match.
+
+    return j;
+}
+
 EXTERN char parallaxtype;
 
 // last sprite in the freelist, that is the spritenum for which
diff --git a/polymer/eduke32/build/src/engine_priv.h b/polymer/eduke32/build/src/engine_priv.h
index 128cf7d6a..d40df0b33 100644
--- a/polymer/eduke32/build/src/engine_priv.h
+++ b/polymer/eduke32/build/src/engine_priv.h
@@ -216,12 +216,7 @@ static inline void bricolor(palette_t *wpptr, int32_t dacol)
 // Returns: pointer to tile offset array. Sets-by-pointer the other two.
 static inline const int8_t *getpsky(int32_t picnum, int32_t *dapyscale, int32_t *dapskybits)
 {
-    int32_t j;
-
-    // First, try a multi-sky.
-    for (j=pskynummultis; j>0; j--)  // NOTE: j==0 on non-early loop end
-        if (picnum == multipskytile[j])
-            break;  // Have a match.
+    int32_t j = getpskyidx(picnum);
 
     if (dapskybits)
         *dapskybits = multipsky[j].lognumtiles;
diff --git a/polymer/eduke32/source/common.c b/polymer/eduke32/source/common.c
index 572eebc65..653b5a29b 100644
--- a/polymer/eduke32/source/common.c
+++ b/polymer/eduke32/source/common.c
@@ -157,7 +157,6 @@ EDUKE32_STATIC_ASSERT(NUMPSKYMULTIS <= MAXPSKYMULTIS);
 EDUKE32_STATIC_ASSERT(PSKYOFF_MAX <= MAXPSKYTILES);
 
 // Set up new-style multi-psky handling.
-// KEEPINSYNC MultiPsky_TileToIdx().
 void G_InitMultiPsky(int32_t CLOUDYOCEAN__DYN, int32_t MOONSKY1__DYN, int32_t BIGORBIT1__DYN, int32_t LA__DYN)
 {
     int32_t i;
@@ -243,7 +242,7 @@ void G_SetupGlobalPsky(void)
     {
         if (sector[i].ceilingstat & 1)
         {
-            mskyidx = MultiPsky_TileToIdx(sector[i].ceilingpicnum);
+            mskyidx = getpskyidx(sector[i].ceilingpicnum);
             if (mskyidx > 0)
                 break;
         }
diff --git a/polymer/eduke32/source/common_game.h b/polymer/eduke32/source/common_game.h
index 01350ed96..ddf60bcfc 100644
--- a/polymer/eduke32/source/common_game.h
+++ b/polymer/eduke32/source/common_game.h
@@ -61,26 +61,6 @@ extern void clearScriptNamePtr(void);
 extern void G_InitMultiPsky(int32_t CLOUDYOCEAN__DYN, int32_t MOONSKY1__DYN, int32_t BIGORBIT1__DYN, int32_t LA__DYN);
 extern void G_SetupGlobalPsky(void);
 
-// Get the multi-psky index corresponding to a base tile number of the sky (for
-// the game: the *static* value!), or 0 as the catch-all.
-// KEEPINSYNC G_InitMultiPsky().
-static inline int32_t MultiPsky_TileToIdx(int32_t tilenum)
-{
-    switch (tilenum)
-    {
-    default:
-        return 0;
-    case 78: // CLOUDYOCEAN__STATIC
-        return 1;
-    case 80: // MOONSKY1__STATIC:
-        return 2;
-    case 84: // BIGORBIT1__STATIC:
-        return 3;
-    case 89: // LA__STATIC:
-        return 4;
-    }
-}
-
 //////////
 
 extern void G_ExtPreInit(void);