diff --git a/source/games/sw/src/ai.cpp b/source/games/sw/src/ai.cpp
index 95f0efa63..965845759 100644
--- a/source/games/sw/src/ai.cpp
+++ b/source/games/sw/src/ai.cpp
@@ -63,7 +63,7 @@ int Distance(int x1, int y1, int x2, int y2)
     else
         min = x2;
 
-    return x2 + y2 - DIV2(min);
+    return x2 + y2 - (min >> 1);
 }
 
 
@@ -119,7 +119,7 @@ void DoActorSetSpeed(DSWActor* actor, uint8_t speed)
     actor->user.speed = speed;
 
     if (ActorFlaming(actor))
-        actor->spr.xvel = actor->user.Attrib->Speed[speed] + DIV2(actor->user.Attrib->Speed[speed]);
+        actor->spr.xvel = actor->user.Attrib->Speed[speed] + (actor->user.Attrib->Speed[speed] >> 1);
     else
         actor->spr.xvel = actor->user.Attrib->Speed[speed];
 }
@@ -233,7 +233,7 @@ int CanHitPlayer(DSWActor* actor)
     // if actor can still see the player
     int zhs, zhh;
 
-    zhs = actor->spr.pos.Z - DIV2(ActorSizeZ(actor));
+    zhs = actor->spr.pos.Z - (ActorSizeZ(actor) >> 1);
 
 
     auto targ = actor->user.targetActor;
@@ -434,7 +434,7 @@ int DoActorOperate(DSWActor* actor)
         return false;
 
     z[0] = actor->spr.pos.Z - ActorSizeZ(actor) + Z(5);
-    z[1] = actor->spr.pos.Z - DIV2(ActorSizeZ(actor));
+    z[1] = actor->spr.pos.Z - (ActorSizeZ(actor) >> 1);
 
     for (i = 0; i < SIZ(z); i++)
     {
diff --git a/source/games/sw/src/draw.cpp b/source/games/sw/src/draw.cpp
index 9c7372ae1..ea7e1871c 100644
--- a/source/games/sw/src/draw.cpp
+++ b/source/games/sw/src/draw.cpp
@@ -953,8 +953,8 @@ void CircleCamera(int *nx, int *ny, int *nz, sectortype** vsect, binangle *nang,
     vy = -ang.bsin(-4);
 
     // lengthen the vector some
-    vx += DIV2(vx);
-    vy += DIV2(vy);
+    vx += vx >> 1;
+    vy += vy >> 1;
 
     vz = q16horiz >> 8;
 
diff --git a/source/games/sw/src/game.h b/source/games/sw/src/game.h
index 30a370113..b3f854e9a 100644
--- a/source/games/sw/src/game.h
+++ b/source/games/sw/src/game.h
@@ -122,6 +122,7 @@ inline int RANDOM(void)
     return randomseed;
 }
 
+#define MOD_P2(number,modby)  ((number) & ((modby)-1))
 #define RANDOM_P2(pwr_of_2) (MOD_P2(RANDOM(),(pwr_of_2)))
 
 //
@@ -195,6 +196,7 @@ inline int32_t FIXED(int32_t msw, int32_t lsw)
 #define NORM_Q16ANGLE(ang) ((ang) & 0x7FFFFFF)
 
 int StdRandomRange(int range);
+
 #define STD_RANDOM_P2(pwr_of_2) (MOD_P2(rand(),(pwr_of_2)))
 
 #define RANDOM_NEG(x,y) ((RANDOM_P2(((x)<<(y))<<1) - (x))<<(y))
diff --git a/source/games/sw/src/jweapon.cpp b/source/games/sw/src/jweapon.cpp
index 7849784b7..663dc21e1 100644
--- a/source/games/sw/src/jweapon.cpp
+++ b/source/games/sw/src/jweapon.cpp
@@ -2213,7 +2213,7 @@ int SpawnShell(DSWActor* actor, int ShellNum)
             HelpMissileLateral(actorNew,1500);
             actorNew->spr.ang = NORM_ANGLE(actorNew->spr.ang-128);
         }
-        actorNew->spr.ang += (RANDOM_P2(128<<5)>>5) - DIV2(128);
+        actorNew->spr.ang += (RANDOM_P2(128<<5)>>5) - (128 / 2);
         actorNew->spr.ang = NORM_ANGLE(actorNew->spr.ang);
 
         // Set the shell number
@@ -2227,7 +2227,7 @@ int SpawnShell(DSWActor* actor, int ShellNum)
         actorNew->spr.ang = NORM_ANGLE(actorNew->spr.ang+512);
         HelpMissileLateral(actorNew,1300);
         actorNew->spr.ang = NORM_ANGLE(actorNew->spr.ang-128-64);
-        actorNew->spr.ang += (RANDOM_P2(128<<5)>>5) - DIV2(128);
+        actorNew->spr.ang += (RANDOM_P2(128<<5)>>5) - (128 / 2);
         actorNew->spr.ang = NORM_ANGLE(actorNew->spr.ang);
 
         // Set the shell number
diff --git a/source/games/sw/src/mytypes.h b/source/games/sw/src/mytypes.h
index 3a0390a6b..3b1105932 100644
--- a/source/games/sw/src/mytypes.h
+++ b/source/games/sw/src/mytypes.h
@@ -34,19 +34,6 @@ Prepared for public release: 03/28/2005 - Charlie Wiederhold, 3D Realms
 #define ON     1
 
 
-/*
-===========================
-=
-= FAST calculations
-=
-===========================
-*/
-
-#define DIV2(x)  ((x) >> 1)
-#define MOD_P2(number,modby)  ((number) & ((modby)-1))
-
-
-
 /*
 ===========================
 =
diff --git a/source/games/sw/src/panel.cpp b/source/games/sw/src/panel.cpp
index 3750adfd0..66b3940b4 100644
--- a/source/games/sw/src/panel.cpp
+++ b/source/games/sw/src/panel.cpp
@@ -6555,7 +6555,6 @@ void pDisplaySprites(PLAYERp pp, double smoothratio)
                 flags |= (RS_TRANS1);
             }
 
-            //shade = overlay_shade = DIV2(pp->cursector->floorshade + pp->cursector->ceilingshade);
             shade = overlay_shade = floorshade - 10;
 
             if (TEST(psp->PlayerP->Flags, PF_VIEW_FROM_OUTSIDE))
diff --git a/source/games/sw/src/player.cpp b/source/games/sw/src/player.cpp
index bf6283449..d51af7a51 100644
--- a/source/games/sw/src/player.cpp
+++ b/source/games/sw/src/player.cpp
@@ -1226,7 +1226,7 @@ DSWActor* DoPickTarget(DSWActor* actor, uint32_t max_delta_ang, int skip_targets
             // gives a value between 0 and 65535
             ang_weight = IntToFixed(max_delta_ang - ts->dang)/max_delta_ang;
             // gives a value between 0 and 65535
-            dist_weight = IntToFixed(DIV2(PICK_DIST) - DIV2(ts->dist))/DIV2(PICK_DIST);
+            dist_weight = IntToFixed((PICK_DIST / 2) - ((ts->dist) >> 1)) / (PICK_DIST / 2);
             //weighted average
             ts->weight = (ang_weight + dist_weight*4)/5;
 
@@ -2618,7 +2618,7 @@ void DoPlayerMoveVehicle(PLAYERp pp)
 
             if (vel > 13000)
             {
-                vec3_t hit_pos = { DIV2(x[0] + x[1]), DIV2(y[0] + y[1]), pp->cursector->floorz - Z(10) };
+                vec3_t hit_pos = { (x[0] + x[1]) >> 1, (y[0] + y[1]) >> 1, pp->cursector->floorz - Z(10) };
 
                 hitscan(hit_pos, pp->cursector,
                     { MOVEx(256, pp->angle.ang.asbuild()), MOVEy(256, pp->angle.ang.asbuild()), 0 },
diff --git a/source/games/sw/src/sector.cpp b/source/games/sw/src/sector.cpp
index f987ff0ae..396234faa 100644
--- a/source/games/sw/src/sector.cpp
+++ b/source/games/sw/src/sector.cpp
@@ -599,7 +599,7 @@ void SectorMidPoint(sectortype* sectp, int *xmid, int *ymid, int *zmid)
     *xmid = xsum / (sectp->wallnum);
     *ymid = ysum / (sectp->wallnum);
 
-    *zmid = DIV2(sectp->floorz + sectp->ceilingz);
+    *zmid = (sectp->floorz + sectp->ceilingz) >> 1;
 }
 
 
@@ -2208,7 +2208,7 @@ void PlayerOperateEnv(PLAYERp pp)
 
                 z[0] = plActor->spr.pos.Z - ActorSizeZ(plActor) - Z(10);
                 z[1] = plActor->spr.pos.Z;
-                z[2] = DIV2(z[0] + z[1]);
+                z[2] = (z[0] + z[1]) >> 1;
 
                 for (unsigned i = 0; i < SIZ(z); i++)
                 {
diff --git a/source/games/sw/src/skull.cpp b/source/games/sw/src/skull.cpp
index 57248153c..b681f54b1 100644
--- a/source/games/sw/src/skull.cpp
+++ b/source/games/sw/src/skull.cpp
@@ -408,7 +408,7 @@ int DoSkullBob(DSWActor* actor)
 
     actor->user.Counter = (actor->user.Counter + (ACTORMOVETICS << 3) + (ACTORMOVETICS << 1)) & 2047;
     actor->spr.pos.Z = actor->user.sz + MulScale(SKULL_BOB_AMT, bsin(actor->user.Counter), 14) +
-            MulScale(DIV2(SKULL_BOB_AMT), bsin(actor->user.Counter), 14);
+            MulScale((SKULL_BOB_AMT / 2), bsin(actor->user.Counter), 14);
 
     return 0;
 }
@@ -785,7 +785,7 @@ int DoBettyBob(DSWActor* actor)
 
     actor->user.Counter = (actor->user.Counter + (ACTORMOVETICS << 3) + (ACTORMOVETICS << 1)) & 2047;
     actor->spr.pos.Z = actor->user.sz + MulScale(BETTY_BOB_AMT, bsin(actor->user.Counter), 14) +
-            MulScale(DIV2(BETTY_BOB_AMT), bsin(actor->user.Counter), 14);
+            MulScale((BETTY_BOB_AMT / 2), bsin(actor->user.Counter), 14);
 
     return 0;
 }
diff --git a/source/games/sw/src/sprite.cpp b/source/games/sw/src/sprite.cpp
index aa1f8261f..f3a73d603 100644
--- a/source/games/sw/src/sprite.cpp
+++ b/source/games/sw/src/sprite.cpp
@@ -1564,7 +1564,7 @@ void SpriteSetup(void)
     {
         // not used yetv
         getzsofslopeptr(actor->spr.sector(), actor->spr.pos.X, actor->spr.pos.Y, &cz, &fz);
-        if (actor->spr.pos.Z > DIV2(cz + fz))
+        if (actor->spr.pos.Z > ((cz + fz) >> 1))
         {
             // closer to a floor
             actor->spr.cstat |= (CSTAT_SPRITE_CLOSE_FLOOR);
diff --git a/source/games/sw/src/track.cpp b/source/games/sw/src/track.cpp
index ec447c28d..42f2b2c5f 100644
--- a/source/games/sw/src/track.cpp
+++ b/source/games/sw/src/track.cpp
@@ -3133,7 +3133,7 @@ bool ActorTrackDecide(TRACK_POINTp tpoint, DSWActor* actor)
         actor->spr.ang = tpoint->ang;
 
         z[0] = actor->spr.pos.Z - ActorSizeZ(actor) + Z(5);
-        z[1] = actor->spr.pos.Z - DIV2(ActorSizeZ(actor));
+        z[1] = actor->spr.pos.Z - (ActorSizeZ(actor) >> 1);
 
         for (i = 0; i < (int)SIZ(z); i++)
         {
diff --git a/source/games/sw/src/weapon.cpp b/source/games/sw/src/weapon.cpp
index 3778c1218..6884d8d1e 100644
--- a/source/games/sw/src/weapon.cpp
+++ b/source/games/sw/src/weapon.cpp
@@ -3639,14 +3639,14 @@ AutoShrap:
 
     hz[Z_TOP] = ActorZOfTop(parentActor);        // top
     hz[Z_BOT] = ActorZOfBottom(parentActor);        // bottom
-    hz[Z_MID] = DIV2(hz[0] + hz[2]);        // mid
+    hz[Z_MID] = (hz[0] + hz[2]) >> 1;        // mid
 
     for (; p->id; p++)
     {
         if (!p->random_disperse)
         {
             //dang = (2048 / p->num);
-            start_ang = NORM_ANGLE(shrap_ang - DIV2(p->ang_range));
+            start_ang = NORM_ANGLE(shrap_ang - (p->ang_range >> 1));
             dang = (p->ang_range / p->num);
         }
 
@@ -3657,7 +3657,7 @@ AutoShrap:
 
             if (p->random_disperse)
             {
-                actor->spr.ang = shrap_ang + (RANDOM_P2(p->ang_range<<5)>>5) - DIV2(p->ang_range);
+                actor->spr.ang = shrap_ang + (RANDOM_P2(p->ang_range<<5)>>5) - (p->ang_range >> 1);
                 actor->spr.ang = NORM_ANGLE(actor->spr.ang);
             }
             else
@@ -4064,7 +4064,7 @@ int SpawnBlood(DSWActor* actor, DSWActor* weapActor, short hit_ang, int hit_x, i
     {
         if (!p->random_disperse)
         {
-            start_ang = NORM_ANGLE(hit_ang - DIV2(p->ang_range)+1024);
+            start_ang = NORM_ANGLE(hit_ang - (p->ang_range >> 1) + 1024);
             dang = (p->ang_range / p->num);
         }
 
@@ -4097,7 +4097,7 @@ int SpawnBlood(DSWActor* actor, DSWActor* weapActor, short hit_ang, int hit_x, i
 
             if (p->random_disperse)
             {
-                actorNew->spr.ang = hit_ang + (RANDOM_P2(p->ang_range<<5)>>5) - DIV2(p->ang_range);
+                actorNew->spr.ang = hit_ang + (RANDOM_P2(p->ang_range<<5)>>5) - (p->ang_range >> 1);
                 actorNew->spr.ang = NORM_ANGLE(actorNew->spr.ang);
             }
             else
@@ -8142,7 +8142,7 @@ bool SlopeBounce(DSWActor* actor, bool *hit_wall)
     getzsofslopeptr(hit_sector, actor->spr.pos.X, actor->spr.pos.Y, &hiz, &loz);
 
     // detect the ceiling and the hit_wall
-    if (actor->spr.pos.Z < DIV2(hiz+loz))
+    if (actor->spr.pos.Z < ((hiz+loz) >> 1))
     {
         if (!TEST(hit_sector->ceilingstat, CSTAT_SECTOR_SLOPE))
             slope = 0;
@@ -11250,7 +11250,7 @@ void InitSpellRing(PLAYERp pp)
 
     ang_diff = 2048 / max_missiles;
 
-    ang_start = NORM_ANGLE(pp->angle.ang.asbuild() - DIV2(2048));
+    ang_start = NORM_ANGLE(pp->angle.ang.asbuild() - (2048 / 2));
 
     if (!SW_SHAREWARE)
         PlaySound(DIGI_RFWIZ, pp, v3df_none);
@@ -11378,7 +11378,7 @@ int DoSerpRing(DSWActor* actor)
                     actor->user.ID = SKULL_R0;
                     actor->spr.ang = getangle(actor->user.targetActor->spr.pos.X - actor->spr.pos.X, actor->user.targetActor->spr.pos.Y - actor->spr.pos.Y);
                     actor->spr.xvel = dist>>5;
-                    actor->spr.xvel += DIV2(actor->spr.xvel);
+                    actor->spr.xvel += (actor->spr.xvel >> 1);
                     actor->spr.xvel += (RANDOM_P2(128<<8)>>8);
                     actor->user.jump_speed = -800;
                     change_actor_stat(actor, STAT_ENEMY);
@@ -11463,7 +11463,7 @@ void InitVulcanBoulder(DSWActor* actor)
     if (SP_TAG7(actor))
     {
         delta = SP_TAG5(actor);
-        nang = actor->spr.ang + (RandomRange(delta) - DIV2(delta));
+        nang = actor->spr.ang + (RandomRange(delta) - (delta >> 1));
         nang = NORM_ANGLE(nang);
     }
     else
@@ -11531,7 +11531,7 @@ int InitSerpRing(DSWActor* actor)
 
     ang_diff = 2048 / max_missiles;
 
-    ang_start = NORM_ANGLE(actor->spr.ang - DIV2(2048));
+    ang_start = NORM_ANGLE(actor->spr.ang - (2048 / 2));
 
     PlaySound(DIGI_SERPSUMMONHEADS, actor, v3df_none);
 
@@ -13752,7 +13752,7 @@ int InitMicro(PLAYERp pp)
 
         actorNew->spr.ang = NORM_ANGLE(actorNew->spr.ang + 512);
         const int MICRO_LATERAL = 5000;
-        HelpMissileLateral(actorNew, 1000 + (RandomRange(MICRO_LATERAL) - DIV2(MICRO_LATERAL)));
+        HelpMissileLateral(actorNew, 1000 + (RandomRange(MICRO_LATERAL) - (MICRO_LATERAL / 2)));
         actorNew->spr.ang = NORM_ANGLE(actorNew->spr.ang - 512);
 
         if (TEST(pp->Flags, PF_DIVING) || SpriteInUnderwaterArea(actorNew))
@@ -13789,7 +13789,7 @@ int InitMicro(PLAYERp pp)
         }
         else
         {
-            actorNew->spr.ang = NORM_ANGLE(actorNew->spr.ang + (RandomRange(MICRO_ANG) - DIV2(MICRO_ANG)) - 16);
+            actorNew->spr.ang = NORM_ANGLE(actorNew->spr.ang + (RandomRange(MICRO_ANG) - (MICRO_ANG / 2)) - 16);
         }
 
         actorNew->user.xchange = MOVEx(actorNew->spr.xvel, actorNew->spr.ang);
@@ -13909,7 +13909,7 @@ bool WallSpriteInsideSprite(DSWActor* wactor, DSWActor* actor)
     day = -bcos(wactor->spr.ang) * wactor->spr.xrepeat;
 
     xsiz = tileWidth(wactor->spr.picnum);
-    mid_dist = DIV2(xsiz) + xoff;
+    mid_dist = (xsiz >> 1) + xoff;
 
     // starting from the center find the first point
     x1 -= MulScale(dax, mid_dist, 16);
@@ -15530,7 +15530,7 @@ int InitTurretMicro(DSWActor* actor, PLAYERp pp)
         }
         else
         {
-            actorNew->spr.ang = NORM_ANGLE(actorNew->spr.ang + (RandomRange(MICRO_ANG) - DIV2(MICRO_ANG)) - 16);
+            actorNew->spr.ang = NORM_ANGLE(actorNew->spr.ang + (RandomRange(MICRO_ANG) - (MICRO_ANG / 2)) - 16);
         }
 
         actorNew->user.xchange = MOVEx(actorNew->spr.xvel, actorNew->spr.ang);