diff --git a/asm/bmmap.s b/asm/bmmap.s
index 97da7b13..5da136a1 100644
--- a/asm/bmmap.s
+++ b/asm/bmmap.s
@@ -2,301 +2,6 @@
 
 	.SYNTAX UNIFIED
 
-	THUMB_FUNC_START sub_8019624
-sub_8019624: @ 0x08019624
-	push {r4, r5, r6, r7, lr}
-	mov r7, sl
-	mov r6, r9
-	mov r5, r8
-	push {r5, r6, r7}
-	movs r6, #0
-	ldr r1, _080196FC  @ gBmMapSize
-	movs r2, #2
-	ldrsh r0, [r1, r2]
-	mov r9, r1
-	cmp r6, r0
-	blt _0801963E
-	b _0801976A
-_0801963E:
-	ldr r0, _08019700  @ gUnknown_0859A9D4
-	mov sl, r0
-_08019642:
-	movs r4, #0
-	movs r2, #0
-	ldrsh r0, [r1, r2]
-	adds r1, r6, #1
-	mov r8, r1
-	cmp r4, r0
-	blt _08019652
-	b _0801975C
-_08019652:
-	ldr r2, _08019704  @ gBmMapTerrain
-	mov ip, r2
-	lsls r3, r6, #2
-	mov r7, sl
-	movs r5, #0
-_0801965C:
-	mov r1, ip
-	ldr r0, [r1]
-	adds r0, r3, r0
-	ldr r0, [r0]
-	adds r1, r0, r4
-	ldrb r0, [r1]
-	cmp r0, #0x3c
-	bne _0801974C
-	movs r2, #0
-	cmp r4, #0
-	ble _0801968E
-	subs r0, r1, #1
-	ldrb r0, [r0]
-	cmp r0, #0x17
-	bne _0801967C
-	movs r2, #1
-_0801967C:
-	cmp r0, #0x2d
-	bne _08019682
-	movs r2, #1
-_08019682:
-	cmp r0, #0x20
-	bne _08019688
-	movs r2, #1
-_08019688:
-	cmp r0, #0x21
-	bne _0801968E
-	movs r2, #1
-_0801968E:
-	cmp r6, #0
-	ble _080196B8
-	mov r1, ip
-	ldr r0, [r1]
-	adds r0, r3, r0
-	subs r0, #4
-	ldr r0, [r0]
-	adds r0, r0, r4
-	ldrb r0, [r0]
-	cmp r0, #0x17
-	bne _080196A6
-	adds r2, #2
-_080196A6:
-	cmp r0, #0x2d
-	bne _080196AC
-	adds r2, #2
-_080196AC:
-	cmp r0, #0x20
-	bne _080196B2
-	adds r2, #2
-_080196B2:
-	cmp r0, #0x21
-	bne _080196B8
-	adds r2, #2
-_080196B8:
-	cmp r4, #0
-	ble _080196EC
-	cmp r6, #0
-	ble _080196EC
-	mov r1, ip
-	ldr r0, [r1]
-	adds r1, r3, r0
-	ldr r0, [r1]
-	adds r0, r4, r0
-	subs r0, #1
-	ldrb r0, [r0]
-	cmp r0, #0x17
-	bne _080196EC
-	ldr r0, [r1, #4]
-	adds r0, r4, r0
-	subs r0, #1
-	ldrb r0, [r0]
-	cmp r0, #0x3c
-	bne _080196EC
-	subs r0, r1, #4
-	ldr r0, [r0]
-	adds r0, r0, r4
-	ldrb r0, [r0]
-	cmp r0, #0x17
-	beq _080196EC
-	movs r2, #4
-_080196EC:
-	cmp r2, #2
-	beq _08019720
-	cmp r2, #2
-	bgt _08019708
-	cmp r2, #1
-	beq _08019712
-	b _0801974C
-	.align 2, 0
-_080196FC: .4byte gBmMapSize
-_08019700: .4byte gUnknown_0859A9D4
-_08019704: .4byte gBmMapTerrain
-_08019708:
-	cmp r2, #3
-	beq _0801972E
-	cmp r2, #4
-	beq _0801973C
-	b _0801974C
-_08019712:
-	ldr r0, [r7]
-	adds r0, r3, r0
-	ldr r0, [r0]
-	adds r0, r5, r0
-	movs r2, #0xb7
-	lsls r2, r2, #2
-	b _08019748
-_08019720:
-	ldr r0, [r7]
-	adds r0, r3, r0
-	ldr r0, [r0]
-	adds r0, r5, r0
-	movs r2, #0xb6
-	lsls r2, r2, #2
-	b _08019748
-_0801972E:
-	ldr r0, [r7]
-	adds r0, r3, r0
-	ldr r0, [r0]
-	adds r0, r5, r0
-	movs r2, #0xd6
-	lsls r2, r2, #2
-	b _08019748
-_0801973C:
-	ldr r0, [r7]
-	adds r0, r3, r0
-	ldr r0, [r0]
-	adds r0, r5, r0
-	movs r2, #0xd7
-	lsls r2, r2, #2
-_08019748:
-	adds r1, r2, #0
-	strh r1, [r0]
-_0801974C:
-	adds r5, #2
-	adds r4, #1
-	mov r1, r9
-	movs r2, #0
-	ldrsh r0, [r1, r2]
-	cmp r4, r0
-	bge _0801975C
-	b _0801965C
-_0801975C:
-	mov r6, r8
-	mov r1, r9
-	movs r2, #2
-	ldrsh r0, [r1, r2]
-	cmp r6, r0
-	bge _0801976A
-	b _08019642
-_0801976A:
-	pop {r3, r4, r5}
-	mov r8, r3
-	mov r9, r4
-	mov sl, r5
-	pop {r4, r5, r6, r7}
-	pop {r0}
-	bx r0
-
-	THUMB_FUNC_START sub_8019778
-sub_8019778: @ 0x08019778
-	push {lr}
-	ldr r0, _0801979C  @ gUnknown_02001000
-	ldr r1, _080197A0  @ gUnknown_0202BCF0
-	ldrb r1, [r1, #0xe]
-	lsls r1, r1, #0x18
-	asrs r1, r1, #0x18
-	bl LoadChapterMap
-	bl FlushTilesFromBuffer
-	bl ApplyTrapMapChanges
-	bl FlushTerrainData
-	bl sub_8019624
-	pop {r0}
-	bx r0
-	.align 2, 0
-_0801979C: .4byte gUnknown_02001000
-_080197A0: .4byte gUnknown_0202BCF0
-
-	THUMB_FUNC_START SetupMapRowPointers
-SetupMapRowPointers: @ 0x080197A4
-	push {r4, r5, r6, r7, lr}
-	mov ip, r1
-	adds r6, r2, #0
-	adds r5, r3, #0
-	ldr r2, _080197E0  @ gUnknown_03000808
-	str r0, [r2]
-	adds r6, #2
-	adds r5, #4
-	lsls r1, r5, #2
-	adds r4, r0, r1
-	movs r3, #0
-	adds r7, r2, #0
-	cmp r3, r5
-	bge _080197D0
-_080197C0:
-	ldr r1, [r2]
-	lsls r0, r3, #2
-	adds r0, r0, r1
-	str r4, [r0]
-	adds r4, r4, r6
-	adds r3, #1
-	cmp r3, r5
-	blt _080197C0
-_080197D0:
-	ldr r0, [r7]
-	adds r0, #8
-	mov r1, ip
-	str r0, [r1]
-	pop {r4, r5, r6, r7}
-	pop {r0}
-	bx r0
-	.align 2, 0
-_080197E0: .4byte gUnknown_03000808
-
-	THUMB_FUNC_START ClearMapWith
-ClearMapWith: @ 0x080197E4
-	push {r4, r5, lr}
-	sub sp, #4
-	adds r5, r0, #0
-	adds r3, r1, #0
-	ldr r0, _0801983C  @ gBmMapSize
-	movs r2, #2
-	ldrsh r1, [r0, r2]
-	adds r1, #4
-	movs r2, #0
-	ldrsh r0, [r0, r2]
-	adds r0, #2
-	adds r4, r1, #0
-	muls r4, r0, r4
-	movs r0, #1
-	ands r0, r4
-	cmp r0, #0
-	beq _08019808
-	subs r4, #1
-_08019808:
-	movs r0, #0xff
-	ands r3, r0
-	lsls r0, r3, #8
-	adds r3, r3, r0
-	mov r0, sp
-	strh r3, [r0]
-	adds r0, r5, #0
-	subs r0, #8
-	ldr r1, [r0]
-	lsrs r2, r4, #0x1f
-	adds r2, r4, r2
-	lsls r2, r2, #0xa
-	lsrs r2, r2, #0xb
-	movs r0, #0x80
-	lsls r0, r0, #0x11
-	orrs r2, r0
-	mov r0, sp
-	bl CpuSet
-	adds r0, r5, #0
-	bl SetSubjectMap
-	add sp, #4
-	pop {r4, r5}
-	pop {r0}
-	bx r0
-	.align 2, 0
-_0801983C: .4byte gBmMapSize
-
 	THUMB_FUNC_START sub_8019840
 sub_8019840: @ 0x08019840
 	push {r4, r5, r6, r7, lr}
diff --git a/include/constants/terrains.h b/include/constants/terrains.h
new file mode 100644
index 00000000..206dc698
--- /dev/null
+++ b/include/constants/terrains.h
@@ -0,0 +1,77 @@
+#ifndef GUARD_CONSTANTS_TERRAINS_H
+#define GUARD_CONSTANTS_TERRAINS_H
+
+enum {
+	// Terrain identifiers
+
+	// I'm going by the in-game names + some old FE7 nmm for this
+	// TODO: figure out in better details
+
+	TERRAIN_TILE_00    = 0x00,
+	TERRAIN_PLAINS     = 0x01,
+	TERRAIN_ROAD       = 0x02,
+	TERRAIN_VILLAGE_03 = 0x03,
+	TERRAIN_VILLAGE_04 = 0x04,
+	TERRIAN_HOUSE      = 0x05,
+	TERRAIN_ARMORY     = 0x06,
+	TERRAIN_VENDOR     = 0x07,
+	TERRAIN_ARENA_08   = 0x08,
+	TERRAIN_C_ROOM_09  = 0x09,
+	TERRAIN_FORT       = 0x0A,
+	TERRAIN_GATE_0B    = 0x0B,
+	TERRAIN_FOREST     = 0x0C,
+	TERRAIN_THICKET    = 0x0D,
+	TERRAIN_SAND       = 0x0E,
+	TERRAIN_DESERT     = 0x0F,
+	TERRAIN_RIVER      = 0x10,
+	TERRAIN_MOUNTAIN   = 0x11,
+	TERRAIN_PEAK       = 0x12,
+	TERRAIN_BRIDGE_13  = 0x13,
+	TERRAIN_BRIDGE_14  = 0x14,
+	TERRAIN_SEA        = 0x15,
+	TERRAIN_LAKE       = 0x16,
+	TERRAIN_FLOOR_17   = 0x17,
+	TERRAIN_FLOOR_18   = 0x18,
+	TERRAIN_FENCE_19   = 0x19,
+	TERRAIN_WALL_1A    = 0x1A,
+	TERRAIN_WALL_1B    = 0x1B,
+	TERRAIN_RUBBLE     = 0x1C,
+	TERRAIN_PILLAR     = 0x1D,
+	TERRAIN_DOOR       = 0x1E,
+	TERRAIN_THRONE     = 0x1F,
+	TERRAIN_CHEST_20   = 0x20,
+	TERRAIN_CHEST_21   = 0x21,
+	TERRAIN_ROOF       = 0x22,
+	TERRAIN_GATE_23    = 0x23,
+	TERRAIN_CHURCH     = 0x24,
+	TERRAIN_RUINS_25   = 0x25,
+	TERRAIN_CLIFF      = 0x26,
+	TERRAIN_BALLISTA_REGULAR = 0x27,
+	TERRAIN_BALLISTA_LONG    = 0x28,
+	TERRAIN_BALLISTA_KILLER  = 0x29,
+	TERRAIN_SHIP_FLAT  = 0x2A,
+	TERRAIN_SHIP_WRECK = 0x2B,
+	TERRAIN_TILE_2C    = 0x2C,
+	TERRAIN_STAIRS     = 0x2D,
+	TERRAIN_TILE_2E    = 0x2E,
+	TERRAIN_GLACIER    = 0x2F,
+	TERRAIN_ARENA_30   = 0x30,
+	TERRAIN_VALLEY     = 0x31,
+	TERRAIN_FENCE_32   = 0x32,
+	TERRAIN_SNAG       = 0x33,
+	TERRAIN_BRIDGE_34  = 0x34,
+	TERRAIN_SKY        = 0x35,
+	TERRAIN_DEEPS      = 0x36,
+	TERRAIN_RUINS_37   = 0x37,
+	TERRAIN_INN        = 0x38,
+	TERRAIN_BARREL     = 0x39,
+	TERRAIN_BONE       = 0x3A,
+	TERRAIN_DARK       = 0x3B,
+	TERRAIN_WATER      = 0x3C,
+	TERRAIN_GUNNELS    = 0x3D,
+	TERRAIN_DECK       = 0x3E,
+	TERRAIN_BRACE      = 0x3F,
+	TERRAIN_MAST       = 0x40,
+};
+
+#endif // GUARD_CONSTANTS_TERRAINS_H
diff --git a/include/functions.h b/include/functions.h
index 7fc4f459..ffbc9c36 100644
--- a/include/functions.h
+++ b/include/functions.h
@@ -859,7 +859,7 @@ void FillMovementMapSomehow(int x, int y, const s8* movCostLookup);
 // ??? FillMapStaffRangeForUnit(???);
 // ??? ApplyStuffToRangeMaps(???);
 // ??? sub_801B950(???);
-// ??? SetSubjectMap(???);
+void SetSubjectMap(u8** map);
 // ??? FillRangeMap(???);
 // ??? GetCurrentMovCostTable(???);
 // ??? sub_801B9EC(???);
diff --git a/src/bmmap.c b/src/bmmap.c
index ae001c9d..326ff8bb 100644
--- a/src/bmmap.c
+++ b/src/bmmap.c
@@ -1,9 +1,11 @@
 #include "global.h"
 
+#include "constants/terrains.h"
+
 void InitChapterMap(int chapterId);
-// ??? sub_80195BC(???);
+void sub_80195BC(int chapterId);
 void sub_8019624(void);
-// ??? sub_8019778(???);
+void sub_8019778(void);
 void SetupMapRowPointers(void* buffer, u8*** outHandle, int width, int height);
 void ClearMapWith(u8** map, int value);
 // ??? sub_8019840(???);
@@ -61,6 +63,9 @@ extern u8 gBmMapFogPool[];
 extern u8 gBmMapHiddenPool[];
 extern u8 gBmMapUnkPool[];
 
+extern u16** const gUnknown_0859A9D4;
+extern u8** gUnknown_03000808;
+
 void InitChapterMap(int chapterId) {
 	LoadChapterMap(gUnknown_02001000, chapterId);
 	LoadChapterMapGfx(chapterId);
@@ -97,3 +102,117 @@ void sub_80195BC(int chapterId) {
 	FlushTilesFromBuffer();
 	FlushTerrainData();
 }
+
+void sub_8019624(void) {
+	int ix, iy;
+
+	// Automatic water shadows?
+
+	for (iy = 0; iy < gBmMapSize.height; ++iy) {
+		for (ix = 0; ix < gBmMapSize.width; ++ix) {
+			int connexion;
+
+			if (gBmMapTerrain[iy][ix] != TERRAIN_WATER)
+				continue;
+
+			connexion = 0;
+
+			if (ix > 0) {
+				if (gBmMapTerrain[iy][ix - 1] == TERRAIN_FLOOR_17)
+					connexion = 1;
+
+				if (gBmMapTerrain[iy][ix - 1] == TERRAIN_STAIRS)
+					connexion = 1;
+
+				if (gBmMapTerrain[iy][ix - 1] == TERRAIN_CHEST_20)
+					connexion = 1;
+
+				if (gBmMapTerrain[iy][ix - 1] == TERRAIN_CHEST_21)
+					connexion = 1;
+			}
+
+			if (iy > 0) {
+				if (gBmMapTerrain[iy - 1][ix] == TERRAIN_FLOOR_17)
+					connexion += 2;
+
+				if (gBmMapTerrain[iy - 1][ix] == TERRAIN_STAIRS)
+					connexion += 2;
+
+				if (gBmMapTerrain[iy - 1][ix] == TERRAIN_CHEST_20)
+					connexion += 2;
+
+				if (gBmMapTerrain[iy - 1][ix] == TERRAIN_CHEST_21)
+					connexion += 2;
+			}
+
+			if (ix > 0 && iy > 0)
+				if ((gBmMapTerrain[iy]    [ix - 1] == TERRAIN_FLOOR_17) &&
+					(gBmMapTerrain[iy + 1][ix - 1] == TERRAIN_WATER) &&
+					(gBmMapTerrain[iy - 1][ix]     != TERRAIN_FLOOR_17))
+					connexion = 4;
+
+			switch (connexion) {
+
+			case 1: // straight shadow on the left
+				gUnknown_0859A9D4[iy][ix] = 0x2DC;
+				break;
+
+			case 2: // straight shadow on the top
+				gUnknown_0859A9D4[iy][ix] = 0x2D8;
+				break;
+
+			case 3: // shadow on both the left and the top
+				gUnknown_0859A9D4[iy][ix] = 0x358;
+				break;
+
+			case 4: // shadow on the left, but stronger at the top-left than bottom-left
+				gUnknown_0859A9D4[iy][ix] = 0x35C;
+				break;
+
+			} // switch (connexion)
+		}
+	}
+}
+
+void sub_8019778(void) {
+	LoadChapterMap(gUnknown_02001000, gUnknown_0202BCF0.chapterIndex);
+
+	FlushTilesFromBuffer();
+	ApplyTrapMapChanges();
+	FlushTerrainData();
+	sub_8019624();
+}
+
+void SetupMapRowPointers(void* buffer, u8*** outHandle, int width, int height) {
+	int i;
+	u8* itBuffer;
+
+	gUnknown_03000808 = buffer;
+
+	width  += 2; // two tiles on each edge (shared)
+	height += 4; // two tiles on each edge
+
+	itBuffer = buffer + height * sizeof(u8*);
+
+	for (i = 0; i < height; ++i) {
+		gUnknown_03000808[i] = itBuffer;
+		itBuffer += width;
+	}
+
+	// first row is actually the third, ensuring the top two map rows as safety
+	*outHandle = gUnknown_03000808 + 2;
+}
+
+void ClearMapWith(u8** map, int value) {
+	int size = (gBmMapSize.height + 4) * (gBmMapSize.width + 2);
+
+	if (size % 2)
+		size = size - 1;
+
+	value = (0xFF & value);
+	value += value << 8;
+
+	CpuFill16(value, map[-2], size);
+
+	SetSubjectMap(map);
+}