diff --git a/asm/pokenav.s b/asm/pokenav.s
index 765b1c0c7a..b242118aa9 100755
--- a/asm/pokenav.s
+++ b/asm/pokenav.s
@@ -10886,7 +10886,7 @@ sub_81CC6A4: @ 81CC6A4
 	bl TransferPlttBuffer
 	bl LoadOam
 	bl ProcessSpriteCopyRequests
-	bl sub_81237B4
+	bl UpdateRegionMapVideoRegs
 	pop {r0}
 	bx r0
 	thumb_func_end sub_81CC6A4
diff --git a/asm/region_map.s b/asm/region_map.s
index 892cf338c2..e6eca9691b 100644
--- a/asm/region_map.s
+++ b/asm/region_map.s
@@ -5,80 +5,6 @@
 
 	.text
 
-	thumb_func_start sub_8123824
-sub_8123824: @ 8123824
-	push {r4,r5,lr}
-	sub sp, 0xC
-	lsls r0, 16
-	asrs r4, r0, 16
-	lsls r1, 16
-	asrs r5, r1, 16
-	movs r0, 0x80
-	lsls r0, 1
-	str r0, [sp]
-	str r0, [sp, 0x4]
-	movs r0, 0
-	str r0, [sp, 0x8]
-	adds r0, r4, 0
-	adds r1, r5, 0
-	movs r2, 0x38
-	movs r3, 0x48
-	bl CalcZoomScrollParams
-	bl sub_81237B4
-	ldr r0, =gRegionMap
-	ldr r2, [r0]
-	ldr r1, [r2, 0x20]
-	cmp r1, 0
-	beq _08123860
-	negs r0, r4
-	strh r0, [r1, 0x24]
-	ldr r1, [r2, 0x20]
-	negs r0, r5
-	strh r0, [r1, 0x26]
-_08123860:
-	add sp, 0xC
-	pop {r4,r5}
-	pop {r0}
-	bx r0
-	.pool
-	thumb_func_end sub_8123824
-
-	thumb_func_start sub_812386C
-sub_812386C: @ 812386C
-	push {lr}
-	lsls r0, 16
-	lsrs r3, r0, 16
-	lsls r1, 16
-	ldr r0, =0xfffe0000
-	adds r1, r0
-	lsrs r2, r1, 16
-	cmp r2, 0xE
-	bhi _08123886
-	cmp r3, 0
-	beq _08123886
-	cmp r3, 0x1C
-	bls _08123890
-_08123886:
-	movs r0, 0xD5
-	b _081238A4
-	.pool
-_08123890:
-	subs r0, r3, 0x1
-	lsls r0, 16
-	lsrs r3, r0, 16
-	ldr r1, =gUnknown_085A096C
-	lsls r0, r2, 3
-	subs r0, r2
-	lsls r0, 2
-	adds r0, r3, r0
-	adds r0, r1
-	ldrb r0, [r0]
-_081238A4:
-	pop {r1}
-	bx r1
-	.pool
-	thumb_func_end sub_812386C
-
 	thumb_func_start sub_81238AC
 sub_81238AC: @ 81238AC
 	push {r4-r7,lr}
@@ -826,7 +752,7 @@ sub_8123E9C: @ 8123E9C
 	lsrs r0, 16
 	lsls r1, 16
 	lsrs r1, 16
-	bl sub_812386C
+	bl GetRegionMapSectionIdAt
 	lsls r0, 16
 	lsrs r0, 16
 	pop {r1}
@@ -1007,7 +933,7 @@ _08123FE6:
 	lsrs r4, r0, 16
 	adds r0, r4, 0
 	adds r1, r5, 0
-	bl sub_812386C
+	bl GetRegionMapSectionIdAt
 	ldr r1, =gRegionMap
 	ldr r1, [r1]
 	lsls r0, 16
@@ -1063,7 +989,7 @@ _08124058:
 _0812405A:
 	adds r0, r4, 0
 	adds r1, r5, 0
-	bl sub_812386C
+	bl GetRegionMapSectionIdAt
 	ldr r1, =gRegionMap
 	ldr r1, [r1]
 	lsls r0, 16
diff --git a/include/region_map.h b/include/region_map.h
index eb8bb3222b..b784e26ec3 100644
--- a/include/region_map.h
+++ b/include/region_map.h
@@ -218,7 +218,8 @@ enum {
     MAPSEC_DESERT_UNDERPASS,
     MAPSEC_ALTERING_CAVE_2,
     MAPSEC_NAVEL_ROCK2,
-    MAPSEC_TRAINER_HILL
+    MAPSEC_TRAINER_HILL,
+    MAPSEC_NONE2
 };
 
 struct RegionMap {
diff --git a/src/region_map.c b/src/region_map.c
index 0a2da354a1..b771d70280 100644
--- a/src/region_map.c
+++ b/src/region_map.c
@@ -8,6 +8,13 @@
 #include "trig.h"
 #include "region_map.h"
 
+#define MAP_WIDTH 28
+#define MAP_HEIGHT 15
+#define MAPCURSOR_X_MIN 1
+#define MAPCURSOR_Y_MIN 2
+#define MAPCURSOR_X_MAX (MAPCURSOR_X_MIN + MAP_WIDTH - 1)
+#define MAPCURSOR_Y_MAX (MAPCURSOR_Y_MIN + MAP_HEIGHT - 1)
+
 // Static type declarations
 
 struct UnkStruct_0203A148 {
@@ -26,12 +33,12 @@ static u8 MoveRegionMapCursor_Full(void);
 static u8 ProcessRegionMapInput_Zoomed(void);
 static u8 MoveRegionMapCursor_Zoomed(void);
 void CalcZoomScrollParams(s16 scrollX, s16 scrollY, s16 c, s16 d, u16 e, u16 f, u8 rotation);
-void sub_81237B4(void);
+void UpdateRegionMapVideoRegs(void);
 void sub_81238AC(void);
 u8 get_flagnr_blue_points(u16 mapSecId);
 u16 sub_8123EB4(u16 mapSecId);
 void sub_8123FB0(void);
-u16 sub_812386C(u16 x, u16 y);
+u16 GetRegionMapSectionIdAt(u16 x, u16 y);
 void sub_812378C(s16 x, s16 y);
 void sub_8124238(void);
 void sub_81243B0(void);
@@ -39,11 +46,12 @@ void sub_81243DC(void);
 
 // .rodata
 
-extern const u8 gUnknown_0859F77C[];
-extern const u8 gUnknown_085A04E0[];
-extern const u16 gUnknown_0859F73C[];
 extern const u8 gUnknown_0859F60C[];
 extern const u8 gUnknown_0859F650[];
+extern const u16 gUnknown_0859F73C[];
+extern const u8 gUnknown_0859F77C[];
+extern const u8 gUnknown_085A04E0[];
+extern const u8 gUnknown_085A096C[];
 
 // .text
 
@@ -146,7 +154,7 @@ bool8 sub_8122DB0(void)
             break;
         case 7:
             sub_8123FB0();
-            sub_81237B4();
+            UpdateRegionMapVideoRegs();
             gRegionMap->cursorSprite = NULL;
             gRegionMap->playerIconSprite = NULL;
             gRegionMap->cursorMovementFrameCounter = 0;
@@ -202,22 +210,22 @@ static u8 ProcessRegionMapInput_Full(void)
     input = INPUT_EVENT_NONE;
     gRegionMap->cursorDeltaX = 0;
     gRegionMap->cursorDeltaY = 0;
-    if (gMain.heldKeys & DPAD_UP && gRegionMap->cursorPosY > 2)
+    if (gMain.heldKeys & DPAD_UP && gRegionMap->cursorPosY > MAPCURSOR_Y_MIN)
     {
         gRegionMap->cursorDeltaY = -1;
         input = INPUT_EVENT_MOVE_START;
     }
-    if (gMain.heldKeys & DPAD_DOWN && gRegionMap->cursorPosY < 16)
+    if (gMain.heldKeys & DPAD_DOWN && gRegionMap->cursorPosY < MAPCURSOR_Y_MAX)
     {
         gRegionMap->cursorDeltaY = +1;
         input = INPUT_EVENT_MOVE_START;
     }
-    if (gMain.heldKeys & DPAD_LEFT && gRegionMap->cursorPosX > 1)
+    if (gMain.heldKeys & DPAD_LEFT && gRegionMap->cursorPosX > MAPCURSOR_X_MIN)
     {
         gRegionMap->cursorDeltaX = -1;
         input = INPUT_EVENT_MOVE_START;
     }
-    if (gMain.heldKeys & DPAD_RIGHT && gRegionMap->cursorPosX < 28)
+    if (gMain.heldKeys & DPAD_RIGHT && gRegionMap->cursorPosX < MAPCURSOR_X_MAX)
     {
         gRegionMap->cursorDeltaX = +1;
         input = INPUT_EVENT_MOVE_START;
@@ -262,7 +270,7 @@ static u8 MoveRegionMapCursor_Full(void)
     {
         gRegionMap->cursorPosY --;
     }
-    mapSecId = sub_812386C(gRegionMap->cursorPosX, gRegionMap->cursorPosY);
+    mapSecId = GetRegionMapSectionIdAt(gRegionMap->cursorPosX, gRegionMap->cursorPosY);
     gRegionMap->unk_002 = get_flagnr_blue_points(mapSecId);
     if (mapSecId != gRegionMap->mapSecId)
     {
@@ -335,7 +343,7 @@ static u8 MoveRegionMapCursor_Zoomed(void)
         {
             gRegionMap->unk_064 = x;
             gRegionMap->unk_066 = y;
-            mapSecId = sub_812386C(x, y);
+            mapSecId = GetRegionMapSectionIdAt(x, y);
             gRegionMap->unk_002 = get_flagnr_blue_points(mapSecId);
             if (mapSecId != gRegionMap->mapSecId)
             {
@@ -477,7 +485,7 @@ void sub_812378C(s16 x, s16 y)
     gRegionMap->needUpdateVideoRegs = TRUE;
 }
 
-void sub_81237B4(void)
+void UpdateRegionMapVideoRegs(void)
 {
     if (gRegionMap->needUpdateVideoRegs)
     {
@@ -492,3 +500,25 @@ void sub_81237B4(void)
         gRegionMap->needUpdateVideoRegs = FALSE;
     }
 }
+
+void sub_8123824(s16 x, s16 y)
+{
+    CalcZoomScrollParams(x, y, 0x38, 0x48, 0x100, 0x100, 0);
+    UpdateRegionMapVideoRegs();
+    if (gRegionMap->playerIconSprite != NULL)
+    {
+        gRegionMap->playerIconSprite->pos2.x = -x;
+        gRegionMap->playerIconSprite->pos2.y = -y;
+    }
+}
+
+u16 GetRegionMapSectionIdAt(u16 x, u16 y)
+{
+    if (y < MAPCURSOR_Y_MIN || y > MAPCURSOR_Y_MAX || x < MAPCURSOR_X_MIN || x > MAPCURSOR_X_MAX)
+    {
+        return MAPSEC_NONE2;
+    }
+    y -= MAPCURSOR_Y_MIN;
+    x -= MAPCURSOR_X_MIN;
+    return gUnknown_085A096C[x + y * MAP_WIDTH];
+}