diff --git a/src/hardware/hw_main.c b/src/hardware/hw_main.c
index 6ef48f222..41e2c5693 100644
--- a/src/hardware/hw_main.c
+++ b/src/hardware/hw_main.c
@@ -5501,17 +5501,12 @@ static void HWR_ProjectSprite(mobj_t *thing)
 	fixed_t spr_offset, spr_topoffset;
 #ifdef ROTSPRITE
 	patch_t *rotsprite = NULL;
-	angle_t arollangle;
-	UINT32 rollangle;
+	INT32 rollangle = 0;
 #endif
 
 	if (!thing)
 		return;
 
-#ifdef ROTSPRITE
-	arollangle = thing->rollangle;
-	rollangle = AngleFixed(arollangle)>>FRACBITS;
-#endif
 	this_scale = FIXED_TO_FLOAT(thing->scale);
 
 	// transform the origin point
@@ -5618,11 +5613,11 @@ static void HWR_ProjectSprite(mobj_t *thing)
 	spr_topoffset = spritecachedinfo[lumpoff].topoffset;
 
 #ifdef ROTSPRITE
-	if (rollangle > 0)
+	if (thing->rollangle)
 	{
+		rollangle = R_GetRollAngle(thing->rollangle);
 		if (!sprframe->rotsprite.cached[rot])
 			R_CacheRotSprite(thing->sprite, (thing->frame & FF_FRAMEMASK), sprinfo, sprframe, rot, flip);
-		rollangle /= ROTANGDIFF;
 		rotsprite = sprframe->rotsprite.patch[rot][rollangle];
 		if (rotsprite != NULL)
 		{
diff --git a/src/r_patch.c b/src/r_patch.c
index 69d5ad1a2..0519d6dc9 100644
--- a/src/r_patch.c
+++ b/src/r_patch.c
@@ -49,8 +49,6 @@
 #endif
 
 static unsigned char imgbuf[1<<26];
-fixed_t cosang2rad[ROTANGLES];
-fixed_t sinang2rad[ROTANGLES];
 
 //
 // R_CheckIfPatch
@@ -1123,6 +1121,24 @@ static UINT16 GetPatchPixel(patch_t *patch, INT32 x, INT32 y, boolean flip)
 }
 
 #ifdef ROTSPRITE
+//
+// R_GetRollAngle
+//
+// Angles precalculated in R_InitSprites.
+//
+fixed_t rollcosang[ROTANGLES];
+fixed_t rollsinang[ROTANGLES];
+INT32 R_GetRollAngle(angle_t rollangle)
+{
+	INT32 ra = AngleFixed(rollangle)>>FRACBITS;
+#if (ROTANGDIFF > 1)
+	ra += (ROTANGDIFF/2);
+#endif
+	ra /= ROTANGDIFF;
+	ra %= ROTANGLES;
+	return ra;
+}
+
 //
 // R_CacheRotSprite
 //
@@ -1180,12 +1196,12 @@ void R_CacheRotSprite(spritenum_t sprnum, UINT8 frame, spriteinfo_t *sprinfo, sp
 			leftoffset = width - leftoffset;
 		}
 
-		for (angle = 0; angle < ROTANGLES; angle++)
+		for (angle = 1; angle < ROTANGLES; angle++)
 		{
 			INT32 newwidth, newheight;
 
-			ca = cosang2rad[angle];
-			sa = sinang2rad[angle];
+			ca = rollcosang[angle];
+			sa = rollsinang[angle];
 
 			// Find the dimensions of the rotated patch.
 			{
diff --git a/src/r_patch.h b/src/r_patch.h
index c534debdb..72371f253 100644
--- a/src/r_patch.h
+++ b/src/r_patch.h
@@ -62,11 +62,12 @@ void R_ParseSPRTINFOLump(UINT16 wadNum, UINT16 lumpNum);
 
 // Sprite rotation
 #ifdef ROTSPRITE
+INT32 R_GetRollAngle(angle_t rollangle);
 void R_CacheRotSprite(spritenum_t sprnum, UINT8 frame, spriteinfo_t *sprinfo, spriteframe_t *sprframe, INT32 rot, UINT8 flip);
 void R_FreeSingleRotSprite(spritedef_t *spritedef);
 void R_FreeSkinRotSprite(size_t skinnum);
-extern fixed_t cosang2rad[ROTANGLES];
-extern fixed_t sinang2rad[ROTANGLES];
+extern fixed_t rollcosang[ROTANGLES];
+extern fixed_t rollsinang[ROTANGLES];
 #endif
 
 #endif // __R_PATCH__
diff --git a/src/r_things.c b/src/r_things.c
index 8a2e9fa55..cd7e40064 100644
--- a/src/r_things.c
+++ b/src/r_things.c
@@ -500,7 +500,7 @@ void R_InitSprites(void)
 {
 	size_t i;
 #ifdef ROTSPRITE
-	INT32 angle, ra;
+	INT32 angle;
 	float fa;
 #endif
 
@@ -508,14 +508,11 @@ void R_InitSprites(void)
 		negonearray[i] = -1;
 
 #ifdef ROTSPRITE
-	for (angle = 0; angle < ROTANGLES; angle++)
+	for (angle = 1; angle < ROTANGLES; angle++)
 	{
-		ra = (ROTANGDIFF * angle);
-		if (!ra)
-			ra = (ROTANGDIFF / 2) + 1;
-		fa = ANG2RAD(FixedAngle(ra<<FRACBITS));
-		cosang2rad[angle] = FLOAT_TO_FIXED(cos(-fa));
-		sinang2rad[angle] = FLOAT_TO_FIXED(sin(-fa));
+		fa = ANG2RAD(FixedAngle((ROTANGDIFF * angle)<<FRACBITS));
+		rollcosang[angle] = FLOAT_TO_FIXED(cos(-fa));
+		rollsinang[angle] = FLOAT_TO_FIXED(sin(-fa));
 	}
 #endif
 
@@ -1129,8 +1126,7 @@ static void R_ProjectSprite(mobj_t *thing)
 	fixed_t spr_offset, spr_topoffset;
 #ifdef ROTSPRITE
 	patch_t *rotsprite = NULL;
-	angle_t arollangle = thing->rollangle;
-	UINT32 rollangle = AngleFixed(arollangle)>>FRACBITS;
+	INT32 rollangle = 0;
 #endif
 
 #ifndef PROPERPAPER
@@ -1262,11 +1258,11 @@ static void R_ProjectSprite(mobj_t *thing)
 	spr_topoffset = spritecachedinfo[lump].topoffset;
 
 #ifdef ROTSPRITE
-	if (rollangle > 0)
+	if (thing->rollangle)
 	{
+		rollangle = R_GetRollAngle(thing->rollangle);
 		if (!sprframe->rotsprite.cached[rot])
 			R_CacheRotSprite(thing->sprite, (thing->frame & FF_FRAMEMASK), sprinfo, sprframe, rot, flip);
-		rollangle /= ROTANGDIFF;
 		rotsprite = sprframe->rotsprite.patch[rot][rollangle];
 		if (rotsprite != NULL)
 		{