diff --git a/source/games/sw/src/actor.cpp b/source/games/sw/src/actor.cpp
index 9d2e495ed..c649d62a3 100644
--- a/source/games/sw/src/actor.cpp
+++ b/source/games/sw/src/actor.cpp
@@ -660,7 +660,7 @@ int DoActorJump(DSWActor* actor)
     }
 
     // adjust height by jump speed
-    actor->spr.pos.Z += actor->user.jump_speed * ACTORMOVETICS;
+    actor->add_int_z(actor->user.jump_speed * ACTORMOVETICS);
 
     // if player gets to close the ceiling while jumping
     int minh = actor->user.hiz + (tileHeight(actor->spr.picnum) << 8);
@@ -715,7 +715,7 @@ int DoActorFall(DSWActor* actor)
     actor->user.jump_speed += actor->user.jump_grav * ACTORMOVETICS;
 
     // adjust player height by jump speed
-    actor->spr.pos.Z += actor->user.jump_speed * ACTORMOVETICS;
+    actor->add_int_z(actor->user.jump_speed * ACTORMOVETICS);
 
     // Stick like glue when you hit the ground
     if (actor->spr.pos.Z > actor->user.loz)
@@ -826,7 +826,7 @@ int DoJump(DSWActor* actor)
     }
 
     // adjust height by jump speed
-    actor->spr.pos.Z += actor->user.jump_speed * ACTORMOVETICS;
+    actor->add_int_z(actor->user.jump_speed * ACTORMOVETICS);
 
     // if player gets to close the ceiling while jumping
     int minh = actor->user.hiz + (tileHeight(actor->spr.picnum) << 8);
@@ -864,7 +864,7 @@ int DoFall(DSWActor* actor)
     actor->user.jump_speed += actor->user.jump_grav * ACTORMOVETICS;
 
     // adjust player height by jump speed
-    actor->spr.pos.Z += actor->user.jump_speed * ACTORMOVETICS;
+    actor->add_int_z(actor->user.jump_speed * ACTORMOVETICS);
 
     // Stick like glue when you hit the ground
     if (actor->spr.pos.Z > actor->user.loz - actor->user.floor_dist)
diff --git a/source/games/sw/src/coolie.cpp b/source/games/sw/src/coolie.cpp
index b4ada0e8c..f4b29e8c7 100644
--- a/source/games/sw/src/coolie.cpp
+++ b/source/games/sw/src/coolie.cpp
@@ -455,7 +455,7 @@ void EnemyDefaults(DSWActor* actor, ACTOR_ACTION_SET* action, PERSONALITY* perso
 
     if (depth && labs(actor->spr.pos.Z - actor->user.loz) < Z(8))
     {
-        actor->spr.pos.Z += Z(depth);
+        actor->add_int_z(Z(depth));
         actor->user.loz = actor->spr.pos.Z;
         actor->backupz();
     }
diff --git a/source/games/sw/src/jweapon.cpp b/source/games/sw/src/jweapon.cpp
index 9b4fcfb1d..ab331f94c 100644
--- a/source/games/sw/src/jweapon.cpp
+++ b/source/games/sw/src/jweapon.cpp
@@ -265,18 +265,18 @@ int DoWallBloodDrip(DSWActor* actor)
         if (actor->spr.pos.Z > actor->user.pos.Y && actor->spr.pos.Z < actor->user.pos.Z)
         {
             actor->spr.zvel += 300;
-            actor->spr.pos.Z += actor->spr.zvel;
+            actor->add_int_z(actor->spr.zvel);
         }
         else
         {
             actor->spr.zvel = (300+RandomRange(2300)) >> 1;
-            actor->spr.pos.Z += actor->spr.zvel;
+            actor->add_int_z(actor->spr.zvel);
         }
     }
     else
     {
         actor->spr.zvel = (300+RandomRange(2300)) >> 1;
-        actor->spr.pos.Z += actor->spr.zvel;
+        actor->add_int_z(actor->spr.zvel);
     }
 
     if (actor->spr.pos.Z >= actor->user.loz)
@@ -357,7 +357,7 @@ int DoBloodSpray(DSWActor* actor)
     if (actor->spr.xvel <= 2)
     {
         // special stuff for blood worm
-        actor->spr.pos.Z += (actor->user.change.Z >> 1);
+        actor->add_int_z((actor->user.change.Z >> 1));
 
         getzsofslopeptr(actor->sector(), actor->spr.pos.X, actor->spr.pos.Y, &cz, &fz);
         // pretend like we hit a sector
@@ -1838,7 +1838,7 @@ int InitBloodSpray(DSWActor* actor, bool dogib, short velocity)
 
 int BloodSprayFall(DSWActor* actor)
 {
-    actor->spr.pos.Z += 1500;
+    actor->add_int_z(1500);
     return 0;
 }
 
@@ -2185,13 +2185,13 @@ int SpawnShell(DSWActor* actor, int ShellNum)
 
     if (actor->user.PlayerP)
     {
-        actorNew->spr.pos.Z += int(-actor->user.PlayerP->horizon.horiz.asbuildf() * HORIZ_MULT * (1. / 3.));
+        actorNew->add_int_z(int(-actor->user.PlayerP->horizon.horiz.asbuildf() * HORIZ_MULT * (1. / 3.)));
     }
 
     switch (actorNew->user.ID)
     {
     case UZI_SHELL:
-        actorNew->spr.pos.Z -= Z(13);
+        actorNew->add_int_z(-Z(13));
 
         if (ShellNum == -3)
         {
@@ -2217,7 +2217,7 @@ int SpawnShell(DSWActor* actor, int ShellNum)
         actorNew->spr.yrepeat = actorNew->spr.xrepeat = 13;
         break;
     case SHOT_SHELL:
-        actorNew->spr.pos.Z -= Z(13);
+        actorNew->add_int_z(-Z(13));
         actorNew->spr.ang = actor->spr.ang;
         HelpMissileLateral(actorNew,2500);
         actorNew->spr.ang = NORM_ANGLE(actorNew->spr.ang+512);
diff --git a/source/games/sw/src/player.cpp b/source/games/sw/src/player.cpp
index ae34536ab..591e19498 100644
--- a/source/games/sw/src/player.cpp
+++ b/source/games/sw/src/player.cpp
@@ -5991,7 +5991,7 @@ void DoPlayerDeathDrown(PLAYER* pp)
         {
             pp->pos.Z += Z(2);
             if (MoveSkip2 == 0)
-                actor->spr.pos.Z += Z(4);
+                actor->add_int_z(Z(4));
 
             // Stick like glue when you hit the ground
             if (pp->pos.Z > pp->loz - PLAYER_DEATH_HEIGHT)
diff --git a/source/games/sw/src/skull.cpp b/source/games/sw/src/skull.cpp
index 2f6afbe26..db807b7c2 100644
--- a/source/games/sw/src/skull.cpp
+++ b/source/games/sw/src/skull.cpp
@@ -238,7 +238,7 @@ int SetupSkull(DSWActor* actor)
 
         actor->user.loz = actor->spr.pos.Z;
         // leave 8 pixels above the ground
-        actor->spr.pos.Z += ActorSizeToTop(actor) - Z(3);;
+        actor->add_int_z(ActorSizeToTop(actor) - Z(3));
     }
     else
     {
@@ -623,7 +623,7 @@ int SetupBetty(DSWActor* actor)
 
         actor->user.loz = actor->spr.pos.Z;
         // leave 8 pixels above the ground
-        actor->spr.pos.Z += ActorSizeToTop(actor) - Z(3);;
+        actor->add_int_z(ActorSizeToTop(actor) - Z(3));
     }
     else
     {
diff --git a/source/games/sw/src/sprite.cpp b/source/games/sw/src/sprite.cpp
index 06eed101a..817a35998 100644
--- a/source/games/sw/src/sprite.cpp
+++ b/source/games/sw/src/sprite.cpp
@@ -2427,7 +2427,7 @@ void SpriteSetup(void)
                     if (SP_TAG9(actor) == 0)
                         SP_TAG9(actor) = 10;
 
-                    actor->spr.pos.Z += Z(30);
+                    actor->add_int_z(Z(30));
 
                     break;
                 }
@@ -6548,12 +6548,12 @@ Collision move_ground_missile(DSWActor* actor, int xchange, int ychange, int cei
         {
             if (actor->user.z_tgt > actor->spr.pos.Z)
             {
-                actor->spr.pos.Z += Z(30);
+                actor->add_int_z(Z(30));
                 return retval;
             }
             else
             {
-                actor->spr.pos.Z -= Z(30);
+                actor->add_int_z(-Z(30));
                 return retval;
             }
         }
diff --git a/source/games/sw/src/track.cpp b/source/games/sw/src/track.cpp
index 0012a6c7d..53bd0498f 100644
--- a/source/games/sw/src/track.cpp
+++ b/source/games/sw/src/track.cpp
@@ -3353,7 +3353,7 @@ bool ActorTrackDecide(TRACK_POINT* tpoint, DSWActor* actor)
             if (bos_z > actor->user.loz)
             {
                 actor->user.pos.Y = (bos_z - actor->spr.pos.Z);
-                actor->spr.pos.Z -= actor->user.pos.Y;
+                actor->add_int_z(-actor->user.pos.Y);
             }
 
             //
@@ -3512,7 +3512,7 @@ int ActorFollowTrack(DSWActor* actor, short locktics)
 
                 ActorLeaveTrack(actor);
                 actor->spr.cstat &= ~(CSTAT_SPRITE_YCENTER);
-                actor->spr.pos.Z += actor->user.pos.Y;
+                actor->add_int_z(actor->user.pos.Y);
 
                 DoActorSetSpeed(actor, SLOW_SPEED);
                 actor->user.ActorActionFunc = NinjaJumpActionFunc;
diff --git a/source/games/sw/src/vator.cpp b/source/games/sw/src/vator.cpp
index 5ac0c2a06..ea7397ffe 100644
--- a/source/games/sw/src/vator.cpp
+++ b/source/games/sw/src/vator.cpp
@@ -318,7 +318,7 @@ void MoveSpritesWithSector(sectortype* sect, int z_amt, bool type)
             }
         }
 
-        actor->spr.pos.Z += z_amt;
+        actor->add_int_z(z_amt);
     }
 }
 
diff --git a/source/games/sw/src/weapon.cpp b/source/games/sw/src/weapon.cpp
index 59bd2f92e..d6f459322 100644
--- a/source/games/sw/src/weapon.cpp
+++ b/source/games/sw/src/weapon.cpp
@@ -3709,7 +3709,7 @@ AutoShrap:
                 break;
             case Vomit1:
                 shrap_bounce = false;
-                actor->spr.pos.Z -= Z(4);
+                actor->add_int_z(-Z(4));
                 shrap_xsize = actor->user.pos.X = 12 + (RANDOM_P2(32<<8)>>8);
                 shrap_ysize = actor->user.pos.Y = 12 + (RANDOM_P2(32<<8)>>8);
                 actor->user.Counter = (RANDOM_P2(2048<<5)>>5);
@@ -3724,7 +3724,7 @@ AutoShrap:
                 break;
             case EMP:
                 shrap_bounce = false;
-                actor->spr.pos.Z -= Z(4);
+                actor->add_int_z(-Z(4));
                 //actor->spr.ang = NORM_ANGLE(actor->spr.ang + 1024);
                 shrap_xsize = actor->user.pos.X = 5 + (RANDOM_P2(4<<8)>>8);
                 shrap_ysize = actor->user.pos.Y = 5 + (RANDOM_P2(4<<8)>>8);
@@ -3743,7 +3743,7 @@ AutoShrap:
 
             if (shrap_rand_zamt)
             {
-                actor->spr.pos.Z += Z(RandomRange(shrap_rand_zamt) - (shrap_rand_zamt/2));
+                actor->add_int_z(Z(RandomRange(shrap_rand_zamt) - (shrap_rand_zamt/2)));
             }
 
             actor->spr.pal = actor->user.spal = uint8_t(shrap_pal);
@@ -4447,13 +4447,13 @@ bool WeaponMoveHit(DSWActor* actor)
 
 int DoUziSmoke(DSWActor* actor)
 {
-    actor->spr.pos.Z -= 200; // !JIM! Make them float up
+    actor->add_int_z(-200); // !JIM! Make them float up
     return 0;
 }
 
 int DoShotgunSmoke(DSWActor* actor)
 {
-    actor->spr.pos.Z -= 200; // !JIM! Make them float up
+    actor->add_int_z(-200); // !JIM! Make them float up
     return 0;
 }
 
@@ -7382,7 +7382,7 @@ int DoStar(DSWActor* actor)
                 SpawnBubble(actor);
         }
 
-        actor->spr.pos.Z += 128 * MISSILEMOVETICS;
+        actor->add_int_z(128 * MISSILEMOVETICS);
 
         DoActorZrange(actor);
         MissileWaterAdjust(actor);
@@ -14626,7 +14626,7 @@ int InitCoolgFire(DSWActor* actor)
 int DoCoolgDrip(DSWActor* actor)
 {
     actor->user.Counter += 220;
-    actor->spr.pos.Z += actor->user.Counter;
+    actor->add_int_z(actor->user.Counter);
 
     if (actor->spr.pos.Z > actor->user.loz - actor->user.floor_dist)
     {
@@ -17162,7 +17162,7 @@ int DoVehicleSmoke(DSWActor* actor)
 
 int DoWaterSmoke(DSWActor* actor)
 {
-    actor->spr.pos.Z -= actor->spr.zvel;
+    actor->add_int_z(-actor->spr.zvel);
     return false;
 }
 
@@ -17225,7 +17225,7 @@ int SpawnSmokePuff(DSWActor* actor)
 
 int DoBubble(DSWActor* actor)
 {
-    actor->spr.pos.Z -= actor->spr.zvel;
+    actor->add_int_z(-actor->spr.zvel);
     actor->spr.zvel += 32;
 
     if (actor->spr.zvel > 768)
@@ -17508,7 +17508,7 @@ int QueueFloorBlood(DSWActor* actor)
     spawnedActor->spr.clipdist = 0;
     spawnedActor->spr.xoffset = spawnedActor->spr.yoffset = 0;
     spawnedActor->spr.pos = actor->spr.pos;
-    spawnedActor->spr.pos.Z += Z(1);
+    spawnedActor->add_int_z(Z(1));
     spawnedActor->spr.ang = RANDOM_P2(2048); // Just make it any old angle
     spawnedActor->spr.shade -= 5;  // Brighten it up just a bit
 
@@ -17838,7 +17838,7 @@ int DoWallBlood(DSWActor* actor)
     if (actor->spr.yrepeat < 80)
     {
         actor->spr.yrepeat++;
-        actor->spr.pos.Z += 128;
+        actor->add_int_z(128);
     }
 
     return 0;