diff --git a/source/build/include/build.h b/source/build/include/build.h
index d1723f35f..2dd305da6 100644
--- a/source/build/include/build.h
+++ b/source/build/include/build.h
@@ -777,6 +777,11 @@ inline walltype* sectortype::firstWall() const
 	return &wall[wallptr]; // cannot be -1 in a proper map
 }
 
+inline walltype* sectortype::lastWall() const
+{
+    return &wall[wallptr + wallnum - 1]; // cannot be -1 in a proper map
+}
+
 inline int cansee(int x1, int y1, int z1, sectortype* sect1, int x2, int y2, int z2, sectortype* sect2)
 {
 	return cansee(x1, y1, z1, sector.IndexOf(sect1), x2, y2, z2, sector.IndexOf(sect2));
diff --git a/source/build/include/buildtypes.h b/source/build/include/buildtypes.h
index 51f026c18..5889386bd 100644
--- a/source/build/include/buildtypes.h
+++ b/source/build/include/buildtypes.h
@@ -142,7 +142,8 @@ struct sectortype
     void addfloorypan(float add) { floorypan_ = fmodf(floorypan_ + add + 512, 256); } // +512 is for handling negative offsets
     void addceilingxpan(float add) { ceilingxpan_ = fmodf(ceilingxpan_ + add + 512, 256); } // +512 is for handling negative offsets
     void addceilingypan(float add) { ceilingypan_ = fmodf(ceilingypan_ + add + 512, 256); } // +512 is for handling negative offsets
-    walltype *firstWall() const;
+    walltype* firstWall() const;
+    walltype* lastWall() const;
 
 
     // These will unfortunately have to be within the base struct to refactor Blood properly. They can later be removed again, once everything is done.
diff --git a/source/games/sw/src/game.h b/source/games/sw/src/game.h
index e01fc0d67..447cd3e61 100644
--- a/source/games/sw/src/game.h
+++ b/source/games/sw/src/game.h
@@ -76,6 +76,9 @@ struct Collision
     int setSprite(DSWActor* num);
     int setSky();
     int setFromEngine(int value);
+
+    walltype* wall() const { assert(type == kHitWall); return &::wall[index]; }
+    sectortype* sector() const { assert(type == kHitSector); return &::sector[index]; }
 };
 
 typedef struct
diff --git a/source/games/sw/src/rotator.cpp b/source/games/sw/src/rotator.cpp
index acf035da9..3ea1b7202 100644
--- a/source/games/sw/src/rotator.cpp
+++ b/source/games/sw/src/rotator.cpp
@@ -234,22 +234,17 @@ bool TestRotatorMatchActive(short match)
 void DoRotatorSetInterp(DSWActor* actor)
 {
     SPRITEp sp = &actor->s();
-    short w,startwall,endwall;
 
-    startwall = sp->sector()->wallptr;
-    endwall = startwall + sp->sector()->wallnum - 1;
-
-    // move points
-    for (w = startwall; w <= endwall; w++)
+    for(auto& wal : wallsofsector(sp->sector()))
     {
-        StartInterpolation(w, Interp_Wall_X);
-        StartInterpolation(w, Interp_Wall_Y);
+        StartInterpolation(&wal, Interp_Wall_X);
+        StartInterpolation(&wal, Interp_Wall_Y);
 
-        uint16_t const nextwall = wall[w].nextwall;
-        if (validWallIndex(nextwall))
+        if (wal.twoSided())
         {
-            StartInterpolation(wall[nextwall].point2, Interp_Wall_X);
-            StartInterpolation(wall[nextwall].point2, Interp_Wall_Y);
+            auto w2 = wal.nextWall()->point2Wall();
+            StartInterpolation(w2, Interp_Wall_X);
+            StartInterpolation(w2, Interp_Wall_Y);
         }
     }
 }
@@ -257,22 +252,16 @@ void DoRotatorSetInterp(DSWActor* actor)
 void DoRotatorStopInterp(DSWActor* actor)
 {
     SPRITEp sp = &actor->s();
-    short w,startwall,endwall;
-
-    startwall = sp->sector()->wallptr;
-    endwall = startwall + sp->sector()->wallnum - 1;
-
-    // move points
-    for (w = startwall; w <= endwall; w++)
+    for (auto& wal : wallsofsector(sp->sector()))
     {
-        StopInterpolation(w, Interp_Wall_X);
-        StopInterpolation(w, Interp_Wall_Y);
+        StopInterpolation(&wal, Interp_Wall_X);
+        StopInterpolation(&wal, Interp_Wall_Y);
 
-        uint16_t const nextwall = wall[w].nextwall;
-        if (validWallIndex(nextwall))
+        if (wal.twoSided())
         {
-            StopInterpolation(wall[nextwall].point2, Interp_Wall_X);
-            StopInterpolation(wall[nextwall].point2, Interp_Wall_Y);
+            auto w2 = wal.nextWall()->point2Wall();
+            StopInterpolation(w2, Interp_Wall_X);
+            StopInterpolation(w2, Interp_Wall_Y);
         }
     }
 }
diff --git a/source/games/sw/src/weapon.cpp b/source/games/sw/src/weapon.cpp
index c2d93d30f..d41771da3 100644
--- a/source/games/sw/src/weapon.cpp
+++ b/source/games/sw/src/weapon.cpp
@@ -19601,15 +19601,7 @@ int DoItemFly(DSWActor* actor)
 
         case kHitWall:
         {
-            short hit_wall,nw,wall_ang;
-            WALLp wph;
-
-            hit_wall = u->coll.index;
-            wph = &wall[hit_wall];
-
-            nw = wall[hit_wall].point2;
-            wall_ang = NORM_ANGLE(getangle(wall[nw].x - wph->x, wall[nw].y - wph->y)+512);
-
+            int wall_ang = NORM_ANGLE(getangle(u->coll.wall()->delta())+512);
             WallBounce(actor, wall_ang);
             ScaleSpriteVector(actor, 32000);
             break;