diff --git a/src/game/bg.c b/src/game/bg.c
index 1f4938656..f02443ede 100644
--- a/src/game/bg.c
+++ b/src/game/bg.c
@@ -1279,7 +1279,7 @@ Gfx *bgRenderRoomInXray(Gfx *gdl, s32 roomnum)
 		return gdl;
 	}
 
-	room0f166df0(roomnum, &globaldrawworldoffset);
+	roomGetPos(roomnum, &globaldrawworldoffset);
 
 	sp54.x = player->eraserpos.x - globaldrawworldoffset.x;
 	sp54.y = player->eraserpos.y - globaldrawworldoffset.y;
@@ -1289,7 +1289,7 @@ Gfx *bgRenderRoomInXray(Gfx *gdl, s32 roomnum)
 	sp40[1] = sp54.f[1];
 	sp40[2] = sp54.f[2];
 
-	gdl = roomPushMtx(gdl, roomnum);
+	gdl = roomApplyMtx(gdl, roomnum);
 	gdl = bgRenderRoomXrayPass(gdl, roomnum, g_Rooms[roomnum].gfxdata->opablocks, true, sp40);
 	gdl = bgRenderRoomXrayPass(gdl, roomnum, g_Rooms[roomnum].gfxdata->xlublocks, true, sp40);
 
@@ -4764,7 +4764,7 @@ Gfx *bgRenderRoomOpaque(Gfx *gdl, s32 roomnum)
 		return gdl;
 	}
 
-	gdl = roomPushMtx(gdl, roomnum);
+	gdl = roomApplyMtx(gdl, roomnum);
 
 	gdl = lightsSetForRoom(gdl, roomnum);
 	gdl = bgRenderRoomPass(gdl, roomnum, g_Rooms[roomnum].gfxdata->opablocks, true);
@@ -4796,7 +4796,7 @@ Gfx *bgRenderRoomXlu(Gfx *gdl, s32 roomnum)
 		if (g_Rooms[roomnum].gfxdata);
 		if (g_Rooms[roomnum].gfxdata);
 
-		gdl = roomPushMtx(gdl, roomnum);
+		gdl = roomApplyMtx(gdl, roomnum);
 		gdl = bgRenderRoomPass(gdl, roomnum, g_Rooms[roomnum].gfxdata->xlublocks, true);
 
 		g_Rooms[roomnum].loaded240 = 1;
diff --git a/src/game/credits.c b/src/game/credits.c
index 4acfbc1fd..82c187125 100644
--- a/src/game/credits.c
+++ b/src/game/credits.c
@@ -1825,7 +1825,7 @@ Gfx *creditsDraw(Gfx *gdl)
 		}
 
 		mtx4LoadIdentity(&sp68);
-		mtx00016054(&sp68, matrix);
+		mtxF2L(&sp68, matrix);
 		camSetWorldToScreenMtxf(&sp68);
 
 		gSPMatrix(gdl++, osVirtualToPhysical(matrix), G_MTX_NOPUSH | G_MTX_LOAD | G_MTX_MODELVIEW);
diff --git a/src/game/explosions.c b/src/game/explosions.c
index 882705a20..9f8ca3c40 100644
--- a/src/game/explosions.c
+++ b/src/game/explosions.c
@@ -1288,7 +1288,7 @@ Gfx *explosionRender(struct prop *prop, Gfx *gdl, bool xlupass)
 
 	if (roomnum != -1) {
 		struct screenbox screenbox;
-		struct coord *coord = roomGetPos(roomnum);
+		struct coord *coord = roomGetPosPtr(roomnum);
 		u32 *colour;
 		s32 tmp;
 
@@ -1301,7 +1301,7 @@ Gfx *explosionRender(struct prop *prop, Gfx *gdl, bool xlupass)
 		gSPClearGeometryMode(gdl++, G_CULL_BOTH | G_FOG);
 		gSPMatrix(gdl++, osVirtualToPhysical(camGetOrthogonalMtxL()), G_MTX_NOPUSH | G_MTX_LOAD | G_MTX_PROJECTION);
 
-		gdl = roomPushMtx(gdl, roomnum);
+		gdl = roomApplyMtx(gdl, roomnum);
 
 		gSPDisplayList(gdl++, g_TexGdl2);
 
diff --git a/src/game/game_006900.c b/src/game/game_006900.c
index 490967176..cdc523269 100644
--- a/src/game/game_006900.c
+++ b/src/game/game_006900.c
@@ -61,7 +61,7 @@ void menuTickTimers(void)
 #if PIRACYCHECKS
 	{
 		u32 *ptr = (u32 *)&mtxGetObfuscatedRomBase;
-		u32 *end = (u32 *)&mtx00016054;
+		u32 *end = (u32 *)&mtxF2L;
 		u32 checksum = 0;
 
 		while (ptr < end) {
diff --git a/src/game/game_13c510.c b/src/game/game_13c510.c
index e383236eb..d221c82af 100644
--- a/src/game/game_13c510.c
+++ b/src/game/game_13c510.c
@@ -141,7 +141,7 @@ void artifactsCalculateGlaresForRoom(s32 roomnum)
 			roomlights = (struct light *)&g_BgLightsFileData[g_Rooms[roomnum].gfxdata->lightsindex * 0x22];
 			s1 = &var800a41a0[g_Rooms[roomnum].gfxdata->lightsindex * 3];
 
-			room0f166a6c(&sp138, roomnum);
+			roomPopulateMtx(&sp138, roomnum);
 			mtx00015f88(currentPlayerGetScaleBg2Gfx(), &sp138);
 			mtx4MultMtx4(camGetMtxF006c(), &sp138, &spf8);
 
diff --git a/src/game/gunfx.c b/src/game/gunfx.c
index bf0550380..85ddf5c3e 100644
--- a/src/game/gunfx.c
+++ b/src/game/gunfx.c
@@ -247,7 +247,7 @@ Gfx *beamRenderGeneric(Gfx *gdl, struct textureconfig *texconfig,
 
 	mtx00015f04(1.0f / arg2, &sp84);
 	mtx00015be0(worldtoscreenmtx, &sp84);
-	mtx00016054(&sp84, spc8);
+	mtxF2L(&sp84, spc8);
 
 	mult = arg5 * arg2;
 
@@ -788,7 +788,7 @@ glabel var7f1accf4
 /*  f0ad1e4:	00001025 */ 	or	$v0,$zero,$zero
 /*  f0ad1e8:	1100026e */ 	beqz	$t0,.L0f0adba4
 /*  f0ad1ec:	27a40148 */ 	addiu	$a0,$sp,0x148
-/*  f0ad1f0:	0c005815 */ 	jal	mtx00016054
+/*  f0ad1f0:	0c005815 */ 	jal	mtxF2L
 /*  f0ad1f4:	8fa50188 */ 	lw	$a1,0x188($sp)
 /*  f0ad1f8:	82230001 */ 	lb	$v1,0x1($s1)
 /*  f0ad1fc:	2401fffe */ 	addiu	$at,$zero,-2
@@ -1585,7 +1585,7 @@ Gfx *beamRender(Gfx *gdl, struct beam *beam, bool arg2, u8 arg3)
 			}
 
 			if (spd8) {
-				mtx00016054(&sp148, sp188);
+				mtxF2L(&sp148, sp188);
 
 				if (beam->weaponnum);
 
@@ -2239,7 +2239,7 @@ Gfx *lasersightRenderDot(Gfx *gdl)
 	mtx00015f88(0.2f, &sp1b0);
 
 	mtx = gfxAllocateMatrix();
-	mtx00016054(&sp1b0, mtx);
+	mtxF2L(&sp1b0, mtx);
 
 	gSPMatrix(gdl++, osVirtualToPhysical(mtx), G_MTX_NOPUSH | G_MTX_LOAD | G_MTX_MODELVIEW);
 
@@ -2425,7 +2425,7 @@ Gfx *lasersightRenderBeam(Gfx *gdl)
 
 	mtx00015f88(0.2f, &sp198);
 	mtx = gfxAllocateMatrix();
-	mtx00016054(&sp198, mtx);
+	mtxF2L(&sp198, mtx);
 
 	gSPMatrix(gdl++, osVirtualToPhysical(mtx), G_MTX_NOPUSH | G_MTX_LOAD | G_MTX_MODELVIEW);
 
diff --git a/src/game/menu.c b/src/game/menu.c
index effdb0f1a..1537c156c 100644
--- a/src/game/menu.c
+++ b/src/game/menu.c
@@ -2326,7 +2326,7 @@ Gfx *menuRenderModels(Gfx *gdl, struct menu840 *thing, s32 arg2)
 		for (i = 0; i < thing->bodymodeldef->nummatrices; i++) {
 			Mtxf sp70;
 			mtx4Copy((Mtxf *)((u32)thing->bodymodel.matrices + i * sizeof(Mtxf)), &sp70);
-			mtx00016054(&sp70, &thing->bodymodel.matrices[i]);
+			mtxF2L(&sp70, &thing->bodymodel.matrices[i]);
 		}
 
 		mtx00016784();
diff --git a/src/game/menugfx.c b/src/game/menugfx.c
index e885ddea9..5b0a22a7a 100644
--- a/src/game/menugfx.c
+++ b/src/game/menugfx.c
@@ -1845,7 +1845,7 @@ Gfx *menugfxRenderBgSuccess(Gfx *gdl)
 
 	modelmtx = gfxAllocateMatrix();
 
-	mtx00016054(&sp110, modelmtx);
+	mtxF2L(&sp110, modelmtx);
 
 	gSPMatrix(gdl++, osVirtualToPhysical(modelmtx), G_MTX_NOPUSH | G_MTX_LOAD | G_MTX_MODELVIEW);
 
diff --git a/src/game/nbomb.c b/src/game/nbomb.c
index 1bb7706b6..db8f0325c 100644
--- a/src/game/nbomb.c
+++ b/src/game/nbomb.c
@@ -136,7 +136,7 @@ Gfx *func0f0073ac(Gfx *gdl, struct coord *pos, f32 arg2)
 	mtx4LoadIdentity(&sp104);
 	mtx4LoadTranslation(pos, &sp104);
 	mtx00015be0(camGetWorldToScreenMtxf(), &sp104);
-	mtx00016054(&sp104, modelmtx);
+	mtxF2L(&sp104, modelmtx);
 
 	gSPMatrix(gdl++, osVirtualToPhysical(modelmtx), G_MTX_NOPUSH | G_MTX_LOAD | G_MTX_MODELVIEW);
 
@@ -397,7 +397,7 @@ Gfx *nbombRender(Gfx *gdl, struct nbomb *nbomb, Gfx *subgdl)
 	mtx4MultMtx4(&sp48, &sp88, &spc8);
 
 	mtx00015be0(camGetWorldToScreenMtxf(), &spc8);
-	mtx00016054(&spc8, mtx);
+	mtxF2L(&spc8, mtx);
 
 	gSPMatrix(gdl++, osVirtualToPhysical(mtx), G_MTX_NOPUSH | G_MTX_LOAD | G_MTX_MODELVIEW);
 
diff --git a/src/game/player.c b/src/game/player.c
index f31a669de..91c58fcd6 100644
--- a/src/game/player.c
+++ b/src/game/player.c
@@ -2676,7 +2676,7 @@ Gfx *playerRenderHealthBar(Gfx *gdl)
 	Mtxf *addr = gfxAllocateMatrix();
 
 	mtx00016ae4(&matrix, 0, 370, 0, 0, 0, 0, 0, 0, -1);
-	mtx00016054(&matrix, addr);
+	mtxF2L(&matrix, addr);
 
 	gSPMatrix(gdl++, osVirtualToPhysical((void *)addr), G_MTX_NOPUSH | G_MTX_LOAD | G_MTX_MODELVIEW);
 	gDPPipeSync(gdl++);
@@ -4180,7 +4180,7 @@ struct var80070ba4 var80070ba4[4][7] = { // [wieldmode][turnmode]
 
 void playerSetGlobalDrawWorldOffset(s32 room)
 {
-	room0f166df0(room, &g_Vars.currentplayer->globaldrawworldoffset);
+	roomGetPos(room, &g_Vars.currentplayer->globaldrawworldoffset);
 
 	g_Vars.currentplayer->globaldrawworldbgoffset.x = g_Vars.currentplayer->globaldrawworldoffset.x;
 	g_Vars.currentplayer->globaldrawworldbgoffset.y = g_Vars.currentplayer->globaldrawworldoffset.y;
@@ -5709,6 +5709,6 @@ void player0f0c3320(Mtxf *matrices, s32 count)
 		sp40.m[3][1] -= g_Vars.currentplayer->globaldrawworldoffset.y;
 		sp40.m[3][2] -= g_Vars.currentplayer->globaldrawworldoffset.z;
 
-		mtx00016054(&sp40, matrices + i);
+		mtxF2L(&sp40, matrices + i);
 	}
 }
diff --git a/src/game/propobj.c b/src/game/propobj.c
index 6d82fd7d6..f67d65a8a 100644
--- a/src/game/propobj.c
+++ b/src/game/propobj.c
@@ -13487,7 +13487,7 @@ Gfx *gfxRenderRadialShadow(Gfx *gdl, f32 x, f32 y, f32 z, f32 angle, f32 radius,
 	mtx = gfxAllocateMatrix();
 	mtx4LoadYRotationWithTranslation(&pos, angle, &spc0);
 	mtx4MultMtx4(camGetWorldToScreenMtxf(), &spc0, &sp80);
-	mtx00016054(&sp80, mtx);
+	mtxF2L(&sp80, mtx);
 
 	for (i = 0; i < 4; i++) {
 		vertices[i].y = 0;
diff --git a/src/game/room.c b/src/game/room.c
index 63166ab33..8354a4446 100644
--- a/src/game/room.c
+++ b/src/game/room.c
@@ -6,48 +6,88 @@
 #include "data.h"
 #include "types.h"
 
-u8 *var800a6660;
-s16 *var800a6664; // room numbers
-s16 *var800a6668;
-f32 *var800a666c;
-Mtxf *var800a6670;
+/**
+ * Room matrices
+ *
+ * Each room that is rendered needs to have a modelview matrix. The matrix can
+ * be pushed onto the displaylist multiple times per frame, even in single player.
+ *
+ * A simple approach would be to allocate these matrices out of graphics memory
+ * as needed, populating and converting them to the RSP's matrix format each time.
+ *
+ * The solution used here keeps a cache of these matrices. This allows the same
+ * matrix to be reused instead of having to allocate, calculate and convert them
+ * each time which saves CPU time and memory. However, the game has to spend
+ * CPU time keeping track of cache usage so it can free slots, and the cache
+ * allocation uses more total memory than on-demand allocations would require,
+ * so this system is perhaps not as beneficial as it seems.
+ *
+ * The cache is implemented using 5 parallel arrays:
+ *
+ * g_RoomMtxAges
+ *  - The number of frames since each cache slot was last used.
+ *  - When it reaches 2 the slot is freed.
+ * g_RoomMtxLinkedRooms
+ *  - The linked room number per cache slot, or -1 if free.
+ * g_RoomMtxBaseRooms
+ *  - The room that each matrix's position is relative to.
+ *  - This is the player's room, as the world is drawn relative to this.
+ * g_RoomMtxScales
+ *  - The scale that is applied to the matrix. Usually 1.
+ * g_RoomMtxMatrices
+ *  - The matrices themselves, in the RSP's matrix format.
+ *
+ * Each room can have at most one matrix slot. When multiplayer is in use, the
+ * same room matrix can be used for both players, but only if they have the same
+ * global draw offset (ie. are in the same room).
+ *
+ * When players are not in the same room but can see the same rooms, each
+ * player's matrix cache invalidates the other's until they move into the same
+ * room or stop looking at each other's rooms.
+ */
 
-s32 var80082050 = 0;
+u8 *g_RoomMtxAges;
+s16 *g_RoomMtxLinkedRooms;
+s16 *g_RoomMtxBaseRooms;
+f32 *g_RoomMtxScales;
+Mtxf *g_RoomMtxMatrices;
+
+s32 g_RoomMtxNumSlots = 0;
 
 void roomSetLastForOffset(s32 room)
 {
 	g_Vars.currentplayer->lastroomforoffset = room;
 }
 
-void room0f1668f0(s32 index, s32 roomnum)
+void roomLinkMtx(s32 index, s32 roomnum)
 {
-	g_Rooms[roomnum].unk10 = index;
-	var800a6664[index] = roomnum;
+	g_Rooms[roomnum].roommtxindex = index;
+	g_RoomMtxLinkedRooms[index] = roomnum;
 }
 
-void room0f16692c(s32 index, s32 roomnum)
+void roomUnlinkMtx(s32 index, s32 roomnum)
 {
-	g_Rooms[roomnum].unk10 = -1;
-	var800a6664[index] = -1;
+	g_Rooms[roomnum].roommtxindex = -1;
+	g_RoomMtxLinkedRooms[index] = -1;
 }
 
-void room0f16696c(s32 index)
+void roomFreeMtx(s32 index)
 {
-	if (var800a6664[index] != -1) {
-		room0f16692c(index, var800a6664[index]);
+	if (g_RoomMtxLinkedRooms[index] != -1) {
+		roomUnlinkMtx(index, g_RoomMtxLinkedRooms[index]);
 	}
 
-	var800a6660[index] = 2;
-	var800a6668[index] = -1;
-	var800a666c[index] = 1;
+	g_RoomMtxAges[index] = 2;
+	g_RoomMtxBaseRooms[index] = -1;
+	g_RoomMtxScales[index] = 1;
 }
 
-s32 room0f1669fc(void)
+s32 roomAllocateMtx(void)
 {
 	s32 i;
 
-	for (i = 0; i < var80082050; i++) {
-		if (var800a6660[i] > 1 && var800a6668[i] == -1) {
+	for (i = 0; i < g_RoomMtxNumSlots; i++) {
+		if (g_RoomMtxAges[i] >= 2 && g_RoomMtxBaseRooms[i] == -1) {
 			return i;
 		}
 	}
@@ -55,7 +95,7 @@ s32 room0f1669fc(void)
 	return 0;
 }
 
-void room0f166a6c(Mtxf *mtx, s32 roomnum)
+void roomPopulateMtx(Mtxf *mtx, s32 roomnum)
 {
 	s32 stagenum = g_Vars.stagenum;
 
@@ -88,53 +128,67 @@ void room0f166a6c(Mtxf *mtx, s32 roomnum)
 	}
 }
 
-s32 room0f166c20(s32 roomnum)
+/**
+ * "Touch" a room's modelview matrix in the cache.
+ *
+ * The function is named after Unix's touch command, which creates a file if
+ * missing and updates the modification time. The function creates the cache
+ * entry if missing and resets the cache entry's age to 0.
+ */
+s32 roomTouchMtx(s32 roomnum)
 {
-	s32 index = g_Rooms[roomnum].unk10;
+	s32 index = g_Rooms[roomnum].roommtxindex;
 	Mtxf mtx;
 
 	if (index == -1
-			|| g_Vars.currentplayer->lastroomforoffset != var800a6668[index]
-			|| var800a666c[index] != var8005ef10[0]) {
+			|| g_Vars.currentplayer->lastroomforoffset != g_RoomMtxBaseRooms[index]
+			|| g_RoomMtxScales[index] != var8005ef10[0]) {
+		// There's no cache for this room or it's invalid.
+		// Unlink the old cache item if any and create a new one.
 		if (index != -1) {
-			room0f16692c(index, roomnum);
+			roomUnlinkMtx(index, roomnum);
 		}
 
-		index = room0f1669fc();
+		index = roomAllocateMtx();
 
-		room0f1668f0(index, roomnum);
-		var800a6660[index] = 0;
+		roomLinkMtx(index, roomnum);
+		g_RoomMtxAges[index] = 0;
 	} else {
-		var800a6660[index] = 0;
+		// The room has an existing, valid cache entry.
+		g_RoomMtxAges[index] = 0;
 		return index;
 	}
 
-	var800a6668[index] = g_Vars.currentplayer->lastroomforoffset;
-	var800a666c[index] = var8005ef10[0];
+	g_RoomMtxBaseRooms[index] = g_Vars.currentplayer->lastroomforoffset;
+	g_RoomMtxScales[index] = var8005ef10[0];
 
-	room0f166a6c(&mtx, roomnum);
-	mtx00016054(&mtx, &var800a6670[index]);
+	roomPopulateMtx(&mtx, roomnum);
+	mtxF2L(&mtx, &g_RoomMtxMatrices[index]);
 
 	return index;
 }
 
-Gfx *roomPushMtx(Gfx *gdl, s32 roomnum)
+/**
+ * Retrieve a room's modelview matrix from cache, or create a new one and cache
+ * it, and apply it to the displaylist.
+ */
+Gfx *roomApplyMtx(Gfx *gdl, s32 roomnum)
 {
-	s32 index = room0f166c20(roomnum);
+	s32 index = roomTouchMtx(roomnum);
 
-	gSPMatrix(gdl++, &var800a6670[index], G_MTX_NOPUSH | G_MTX_LOAD | G_MTX_MODELVIEW);
+	gSPMatrix(gdl++, &g_RoomMtxMatrices[index], G_MTX_NOPUSH | G_MTX_LOAD | G_MTX_MODELVIEW);
 
 	return gdl;
 }
 
-struct coord *roomGetPos(s32 room)
+struct coord *roomGetPosPtr(s32 room)
 {
 	return &g_BgRooms[room].pos;
 }
 
-void room0f166df0(s32 room, struct coord *globaldrawworldoffset)
+void roomGetPos(s32 room, struct coord *pos)
 {
-	globaldrawworldoffset->x = g_BgRooms[room].pos.x;
-	globaldrawworldoffset->y = g_BgRooms[room].pos.y;
-	globaldrawworldoffset->z = g_BgRooms[room].pos.z;
+	pos->x = g_BgRooms[room].pos.x;
+	pos->y = g_BgRooms[room].pos.y;
+	pos->z = g_BgRooms[room].pos.z;
 }
diff --git a/src/game/roomreset.c b/src/game/roomreset.c
index c506b0aec..dd5ab8c01 100644
--- a/src/game/roomreset.c
+++ b/src/game/roomreset.c
@@ -12,26 +12,26 @@ void roomsReset(void)
 {
 	s32 i;
 
-	var80082050 = PLAYERCOUNT() >= 2 ? 200 : 120;
+	g_RoomMtxNumSlots = PLAYERCOUNT() >= 2 ? 200 : 120;
 
-	var800a6660 = mempAlloc(ALIGN16(var80082050), MEMPOOL_STAGE);
-	var800a6664 = mempAlloc(ALIGN16(var80082050 * sizeof(s16)), MEMPOOL_STAGE);
-	var800a6668 = mempAlloc(ALIGN16(var80082050 * sizeof(s16)), MEMPOOL_STAGE);
-	var800a666c = mempAlloc(ALIGN16(var80082050 * sizeof(f32)), MEMPOOL_STAGE);
-	var800a6670 = mempAlloc(ALIGN16(var80082050 * sizeof(Mtxf)), MEMPOOL_STAGE);
+	g_RoomMtxAges = mempAlloc(ALIGN16(g_RoomMtxNumSlots), MEMPOOL_STAGE);
+	g_RoomMtxLinkedRooms = mempAlloc(ALIGN16(g_RoomMtxNumSlots * sizeof(s16)), MEMPOOL_STAGE);
+	g_RoomMtxBaseRooms = mempAlloc(ALIGN16(g_RoomMtxNumSlots * sizeof(s16)), MEMPOOL_STAGE);
+	g_RoomMtxScales = mempAlloc(ALIGN16(g_RoomMtxNumSlots * sizeof(f32)), MEMPOOL_STAGE);
+	g_RoomMtxMatrices = mempAlloc(ALIGN16(g_RoomMtxNumSlots * sizeof(Mtxf)), MEMPOOL_STAGE);
 
 	for (i = 0; i < PLAYERCOUNT(); i++) {
 		g_Vars.players[i]->lastroomforoffset = -1;
 	}
 
-	for (i = 0; i < var80082050; i++) {
-		var800a6664[i] = -1;
-		var800a6660[i] = 2;
-		var800a6668[i] = -1;
-		var800a666c[i] = 1;
+	for (i = 0; i < g_RoomMtxNumSlots; i++) {
+		g_RoomMtxLinkedRooms[i] = -1;
+		g_RoomMtxAges[i] = 2;
+		g_RoomMtxBaseRooms[i] = -1;
+		g_RoomMtxScales[i] = 1;
 	}
 
 	for (i = 0; i < g_Vars.roomcount; i++) {
-		g_Rooms[i].unk10 = -1;
+		g_Rooms[i].roommtxindex = -1;
 	}
 }
diff --git a/src/game/roomtick.c b/src/game/roomtick.c
index 4b3415585..d99c166fa 100644
--- a/src/game/roomtick.c
+++ b/src/game/roomtick.c
@@ -9,12 +9,12 @@ void roomsTick(void)
 {
 	s32 i;
 
-	for (i = 0; i < var80082050; i++) {
-		if (var800a6668[i] >= 0) {
-			var800a6660[i]++;
+	for (i = 0; i < g_RoomMtxNumSlots; i++) {
+		if (g_RoomMtxBaseRooms[i] >= 0) {
+			g_RoomMtxAges[i]++;
 
-			if (var800a6660[i] > 1) {
-				room0f16696c(i);
+			if (g_RoomMtxAges[i] > 1) {
+				roomFreeMtx(i);
 			}
 		}
 	}
diff --git a/src/game/savebuffer.c b/src/game/savebuffer.c
index 3e8877c04..2947370a2 100644
--- a/src/game/savebuffer.c
+++ b/src/game/savebuffer.c
@@ -64,7 +64,7 @@ Gfx *func0f0d479c(Gfx *gdl)
 
 	mtx00016760();
 	func0f0d475c(&mtx);
-	mtx00016054(&mtx, mtx2);
+	mtxF2L(&mtx, mtx2);
 	mtx4LoadIdentity(&mtx);
 
 	guFrustumF(mtx.m,
@@ -72,7 +72,7 @@ Gfx *func0f0d479c(Gfx *gdl)
 			-(f32) viGetHeight() * 0.5f, viGetHeight() * 0.5f,
 			10, 10000, 1);
 
-	mtx00016054(&mtx, mtx1);
+	mtxF2L(&mtx, mtx1);
 	mtx00016784();
 
 	gSPMatrix(gdl++, osVirtualToPhysical(mtx2), G_MTX_NOPUSH | G_MTX_LOAD | G_MTX_MODELVIEW);
@@ -160,7 +160,7 @@ Gfx *func0f0d4a3c(Gfx *gdl, s32 arg1)
 	gDPSetTexturePersp(gdl++, G_TP_PERSP);
 
 	func0f0d4690(&mtx);
-	mtx00016054(&mtx, mtxptr);
+	mtxF2L(&mtx, mtxptr);
 
 	gSPMatrix(gdl++, osVirtualToPhysical(mtxptr), G_MTX_NOPUSH | G_MTX_LOAD | G_MTX_MODELVIEW);
 
@@ -175,7 +175,7 @@ Gfx *func0f0d4c80(Gfx *gdl)
 	func0f0d4690(&mtx);
 	mtx00015df0(0.1f, &mtx);
 	mtx00015e4c(0.1f, &mtx);
-	mtx00016054(&mtx, mtxptr);
+	mtxF2L(&mtx, mtxptr);
 
 	gSPMatrix(gdl++, osVirtualToPhysical(mtxptr), G_MTX_NOPUSH | G_MTX_LOAD | G_MTX_MODELVIEW);
 
diff --git a/src/game/shards.c b/src/game/shards.c
index 0abc5d8f4..905b9c3df 100644
--- a/src/game/shards.c
+++ b/src/game/shards.c
@@ -267,7 +267,7 @@ Gfx *shardsRenderWood(Gfx *gdl)
 							&& shardmtx.m[3][2] < 10000 && shardmtx.m[3][2] > -10000)
 #endif
 					{
-						mtx00016054(&shardmtx, mtx);
+						mtxF2L(&shardmtx, mtx);
 
 						gSPMatrix(gdl++, osVirtualToPhysical(mtx), G_MTX_NOPUSH | G_MTX_LOAD | G_MTX_MODELVIEW);
 
@@ -389,7 +389,7 @@ Gfx *shardsRenderGlass(Gfx *gdl)
 							&& shardmtx.m[3][2] < 10000 && shardmtx.m[3][2] > -10000)
 #endif
 					{
-						mtx00016054(&shardmtx, mtx);
+						mtxF2L(&shardmtx, mtx);
 
 						gSPMatrix(gdl++, osVirtualToPhysical(mtx), G_MTX_NOPUSH | G_MTX_LOAD | G_MTX_MODELVIEW);
 
diff --git a/src/game/smoke.c b/src/game/smoke.c
index b077040b3..36df567ac 100644
--- a/src/game/smoke.c
+++ b/src/game/smoke.c
@@ -632,9 +632,9 @@ Gfx *smokeRender(struct prop *prop, Gfx *gdl, bool xlupass)
 	}
 
 	if (roomnum != -1) {
-		coord = roomGetPos(roomnum);
+		coord = roomGetPosPtr(roomnum);
 
-		room0f166df0(roomnum, &worldoffset);
+		roomGetPos(roomnum, &worldoffset);
 
 		if (smoke->parts[0].size > 0) {
 			f32 x = smoke->parts[0].pos.x - worldoffset.x;
@@ -655,7 +655,7 @@ Gfx *smokeRender(struct prop *prop, Gfx *gdl, bool xlupass)
 		gSPClearGeometryMode(gdl++, G_CULL_BOTH | G_FOG);
 		gSPMatrix(gdl++, osVirtualToPhysical(camGetOrthogonalMtxL()), G_MTX_NOPUSH | G_MTX_LOAD | G_MTX_PROJECTION);
 
-		gdl = roomPushMtx(gdl, roomnum);
+		gdl = roomApplyMtx(gdl, roomnum);
 
 		if (near) {
 			gSPMatrix(gdl++, osVirtualToPhysical(&var800a3448), G_MTX_NOPUSH | G_MTX_MUL | G_MTX_MODELVIEW);
diff --git a/src/game/sparks.c b/src/game/sparks.c
index 603b9ad09..87f56c482 100644
--- a/src/game/sparks.c
+++ b/src/game/sparks.c
@@ -437,7 +437,7 @@ Gfx *sparksRender(Gfx *gdl)
 					mtx00015be0(camGetWorldToScreenMtxf(), &spd4);
 
 					mtx = gfxAllocateMatrix();
-					mtx00016054(&spd4, mtx);
+					mtxF2L(&spd4, mtx);
 
 					gSPMatrix(gdl++, osVirtualToPhysical(mtx), G_MTX_NOPUSH | G_MTX_LOAD | G_MTX_MODELVIEW);
 
diff --git a/src/game/title.c b/src/game/title.c
index 4f582a59d..9aabf9621 100644
--- a/src/game/title.c
+++ b/src/game/title.c
@@ -898,7 +898,7 @@ Gfx *titleRenderPdLogoModel(Gfx *gdl, struct model *model, bool arg2, f32 arg3,
 
 	for (j = 0, k = 0; j < model->filedata->nummatrices; j++, k += sizeof(Mtxf)) {
 		mtx4Copy((Mtxf *)((u32)model->matrices + k), &sp6c);
-		mtx00016054(&sp6c, model->matrices + j);
+		mtxF2L(&sp6c, model->matrices + j);
 	}
 
 	return gdl;
@@ -2560,7 +2560,7 @@ glabel var7f1a8ff4jf
 /*  f01952c:	27a40158 */ 	addiu	$a0,$sp,0x158
 /*  f019530:	8dd9000c */ 	lw	$t9,0xc($t6)
 /*  f019534:	0002c180 */ 	sll	$t8,$v0,0x6
-/*  f019538:	0c0057fd */ 	jal	mtx00016054
+/*  f019538:	0c0057fd */ 	jal	mtxF2L
 /*  f01953c:	03382821 */ 	addu	$a1,$t9,$t8
 /*  f019540:	3c038006 */ 	lui	$v1,%hi(g_TitleModelJpnLogo2)
 /*  f019544:	8c6323f8 */ 	lw	$v1,%lo(g_TitleModelJpnLogo2)($v1)
@@ -2862,7 +2862,7 @@ glabel var7f1a8ff4jf
 /*  f0199a0:	27a400f4 */ 	addiu	$a0,$sp,0xf4
 /*  f0199a4:	8dd9000c */ 	lw	$t9,0xc($t6)
 /*  f0199a8:	0002c180 */ 	sll	$t8,$v0,0x6
-/*  f0199ac:	0c0057fd */ 	jal	mtx00016054
+/*  f0199ac:	0c0057fd */ 	jal	mtxF2L
 /*  f0199b0:	03382821 */ 	addu	$a1,$t9,$t8
 /*  f0199b4:	3c038006 */ 	lui	$v1,%hi(g_TitleModelJpnPd)
 /*  f0199b8:	8c6323fc */ 	lw	$v1,%lo(g_TitleModelJpnPd)($v1)
@@ -2966,7 +2966,7 @@ glabel var7f1a8ff4jf
 /*  f019b38:	27a4005c */ 	addiu	$a0,$sp,0x5c
 /*  f019b3c:	8dee000c */ 	lw	$t6,0xc($t7)
 /*  f019b40:	0002c980 */ 	sll	$t9,$v0,0x6
-/*  f019b44:	0c0057fd */ 	jal	mtx00016054
+/*  f019b44:	0c0057fd */ 	jal	mtxF2L
 /*  f019b48:	01d92821 */ 	addu	$a1,$t6,$t9
 /*  f019b4c:	3c038006 */ 	lui	$v1,%hi(g_TitleModelJpnLogo1)
 /*  f019b50:	8c6323f4 */ 	lw	$v1,%lo(g_TitleModelJpnLogo1)($v1)
@@ -7589,7 +7589,7 @@ Gfx *titleRenderPdLogo(Gfx *gdl)
 
 					for (sp19c = 0, j = 0; sp19c < g_TitleModelJpnLogo2->filedata->nummatrices; sp19c++, j += sizeof(Mtxf)) {
 						mtx4Copy((Mtxf *)((u32)g_TitleModelJpnLogo2->matrices + j), &sp158);
-						mtx00016054(&sp158, g_TitleModelJpnLogo2->matrices + sp19c);
+						mtxF2L(&sp158, g_TitleModelJpnLogo2->matrices + sp19c);
 					}
 				}
 
@@ -7650,7 +7650,7 @@ Gfx *titleRenderPdLogo(Gfx *gdl)
 
 				for (sp14c = 0, j = 0; sp14c < g_TitleModelJpnPd->filedata->nummatrices; sp14c++, j += sizeof(Mtxf)) {
 					mtx4Copy((Mtxf *)((u32)g_TitleModelJpnPd->matrices + j), &spf4);
-					mtx00016054(&spf4, g_TitleModelJpnPd->matrices + sp14c);
+					mtxF2L(&spf4, g_TitleModelJpnPd->matrices + sp14c);
 				}
 			}
 
@@ -7684,7 +7684,7 @@ Gfx *titleRenderPdLogo(Gfx *gdl)
 
 				for (sp9c = 0, j = 0; sp9c < g_TitleModelJpnLogo1->filedata->nummatrices; sp9c++, j += sizeof(Mtxf)) {
 					mtx4Copy((Mtxf *)((u32)g_TitleModelJpnLogo1->matrices + j), &sp5c);
-					mtx00016054(&sp5c, g_TitleModelJpnLogo1->matrices + sp9c);
+					mtxF2L(&sp5c, g_TitleModelJpnLogo1->matrices + sp9c);
 				}
 			}
 		}
@@ -8010,7 +8010,7 @@ Gfx *titleRenderNintendoLogo(Gfx *gdl)
 
 		for (i = 0, j = 0; i < g_TitleModel->filedata->nummatrices; i++, j += sizeof(Mtxf)) {
 			mtx4Copy((Mtxf *)((u32)g_TitleModel->matrices + j), &sp54);
-			mtx00016054(&sp54, g_TitleModel->matrices + i);
+			mtxF2L(&sp54, g_TitleModel->matrices + i);
 		}
 	}
 
@@ -8257,7 +8257,7 @@ Gfx *titleRenderRareLogo(Gfx *gdl)
 		for (i = 0, j = 0; i < g_TitleModel->filedata->nummatrices; i++, j += sizeof(Mtxf)) {
 			Mtxf sp58;
 			mtx4Copy((Mtxf *)((u32)g_TitleModel->matrices + j), &sp58);
-			mtx00016054(&sp58, g_TitleModel->matrices + i);
+			mtxF2L(&sp58, g_TitleModel->matrices + i);
 		}
 	}
 
diff --git a/src/game/wallhit.c b/src/game/wallhit.c
index d69230720..53e21c633 100644
--- a/src/game/wallhit.c
+++ b/src/game/wallhit.c
@@ -1587,7 +1587,7 @@ void wallhitCreateWith20Args(struct coord *relpos, struct coord *arg1, struct co
 				obj->hidden2 |= OBJH2FLAG_HASOPA;
 			}
 		} else {
-			struct coord *roompos = roomGetPos(room);
+			struct coord *roompos = roomGetPosPtr(room);
 
 			if (arg2 != NULL) {
 				f32 xdist = arg2->x - relpos->x;
@@ -1841,7 +1841,7 @@ Gfx *wallhitRenderOpaBgHits(s32 roomnum, Gfx *gdl)
 	prevtexturenum = -1;
 	prev6b = -1;
 
-	gdl = roomPushMtx(gdl, roomnum);
+	gdl = roomApplyMtx(gdl, roomnum);
 
 	wallhit = g_Rooms[roomnum].opawallhits;
 
@@ -1903,7 +1903,7 @@ Gfx *wallhitRenderXluBgHits(s32 roomnum, Gfx *gdl)
 	prevtexturenum = -1;
 	prev6b = -1;
 
-	gdl = roomPushMtx(gdl, roomnum);
+	gdl = roomApplyMtx(gdl, roomnum);
 
 	wallhit = g_Rooms[roomnum].xluwallhits;
 
diff --git a/src/game/weather.c b/src/game/weather.c
index 8ec03eb0e..b6a51d3fb 100644
--- a/src/game/weather.c
+++ b/src/game/weather.c
@@ -967,7 +967,7 @@ glabel var7f1b5780
 /*  f1330a4:	e7b40200 */ 	swc1	$f20,0x200($sp)
 /*  f1330a8:	00408825 */ 	or	$s1,$v0,$zero
 /*  f1330ac:	02002025 */ 	or	$a0,$s0,$zero
-/*  f1330b0:	0c005815 */ 	jal	mtx00016054
+/*  f1330b0:	0c005815 */ 	jal	mtxF2L
 /*  f1330b4:	00402825 */ 	or	$a1,$v0,$zero
 /*  f1330b8:	8fb00de8 */ 	lw	$s0,0xde8($sp)
 /*  f1330bc:	3c0d0102 */ 	lui	$t5,0x102
@@ -2605,7 +2605,7 @@ Gfx *weatherRenderRain(Gfx *gdl, struct weatherdata *weather, s32 arg2)
 
 	mtx = gfxAllocateMatrix();
 
-	mtx00016054(&sp1c8, mtx);
+	mtxF2L(&sp1c8, mtx);
 
 	gSPMatrix(gdl++, osVirtualToPhysical(mtx), G_MTX_NOPUSH | G_MTX_LOAD | G_MTX_MODELVIEW);
 
@@ -3240,7 +3240,7 @@ glabel var7f1b5790
 /*  f1348ac:	e7b40204 */ 	swc1	$f20,0x204($sp)
 /*  f1348b0:	00408825 */ 	or	$s1,$v0,$zero
 /*  f1348b4:	02002025 */ 	or	$a0,$s0,$zero
-/*  f1348b8:	0c005815 */ 	jal	mtx00016054
+/*  f1348b8:	0c005815 */ 	jal	mtxF2L
 /*  f1348bc:	00402825 */ 	or	$a1,$v0,$zero
 /*  f1348c0:	8fb01398 */ 	lw	$s0,0x1398($sp)
 /*  f1348c4:	3c190102 */ 	lui	$t9,0x102
@@ -4660,7 +4660,7 @@ Gfx *weatherRenderSnow(Gfx *gdl, struct weatherdata *weather, s32 arg2)
 
 	mtx = gfxAllocateMatrix();
 
-	mtx00016054(&sp1cc, mtx);
+	mtxF2L(&sp1cc, mtx);
 
 	gSPMatrix(gdl++, osVirtualToPhysical(mtx), G_MTX_NOPUSH | G_MTX_LOAD | G_MTX_MODELVIEW);
 
diff --git a/src/include/bss.h b/src/include/bss.h
index 3f5a9437c..2d8658c9f 100644
--- a/src/include/bss.h
+++ b/src/include/bss.h
@@ -231,11 +231,11 @@ extern s32 g_BgLightsOffsetChecksum;
 extern u32 g_FogEnabled;
 extern u32 var800a65e4;
 extern struct coord *var800a65e8;
-extern u8 *var800a6660;
-extern s16 *var800a6664;
-extern s16 *var800a6668;
-extern f32 *var800a666c;
-extern Mtxf *var800a6670;
+extern u8 *g_RoomMtxAges;
+extern s16 *g_RoomMtxLinkedRooms;
+extern s16 *g_RoomMtxBaseRooms;
+extern f32 *g_RoomMtxScales;
+extern Mtxf *g_RoomMtxMatrices;
 extern struct fileinfo g_FileInfo[NUM_FILES];
 extern u8 *g_VtxBuffers[3];
 extern u8 *g_GfxMemPos;
diff --git a/src/include/data.h b/src/include/data.h
index 1b63c97fb..2e0d01ec2 100644
--- a/src/include/data.h
+++ b/src/include/data.h
@@ -440,7 +440,7 @@ extern u16 var8007fc3c;
 extern s32 g_NumPortalThings;
 extern f32 var8007fcb4;
 extern struct stagetableentry g_Stages[61];
-extern s32 var80082050;
+extern s32 g_RoomMtxNumSlots;
 extern u32 g_GfxNumSwaps;
 extern s32 g_NumReasonsToEndMpMatch;
 extern s32 g_MusicEventQueueLength;
diff --git a/src/include/game/room.h b/src/include/game/room.h
index ae2c9c3dc..f94305dc7 100644
--- a/src/include/game/room.h
+++ b/src/include/game/room.h
@@ -9,14 +9,14 @@ void roomsReset(void);
 void roomsTick(void);
 
 void roomSetLastForOffset(s32 room);
-void room0f1668f0(s32 index, s32 roomnum);
-void room0f16692c(s32 index, s32 roomnum);
-void room0f16696c(s32 index);
-s32 room0f1669fc(void);
-void room0f166a6c(Mtxf *matrix, s32 roomnum);
-s32 room0f166c20(s32 roomnum);
-Gfx *roomPushMtx(Gfx *gdl, s32 roomnum);
-struct coord *roomGetPos(s32 room);
-void room0f166df0(s32 room, struct coord *globaldrawworldoffset);
+void roomLinkMtx(s32 index, s32 roomnum);
+void roomUnlinkMtx(s32 index, s32 roomnum);
+void roomFreeMtx(s32 index);
+s32 roomAllocateMtx(void);
+void roomPopulateMtx(Mtxf *matrix, s32 roomnum);
+s32 roomTouchMtx(s32 roomnum);
+Gfx *roomApplyMtx(Gfx *gdl, s32 roomnum);
+struct coord *roomGetPosPtr(s32 room);
+void roomGetPos(s32 room, struct coord *pos);
 
 #endif
diff --git a/src/include/lib/mtx.h b/src/include/lib/mtx.h
index faf780653..4b120b058 100644
--- a/src/include/lib/mtx.h
+++ b/src/include/lib/mtx.h
@@ -28,7 +28,7 @@ void mtx00015f04(f32 scale, Mtxf *arg1);
 void mtx00015f4c(f32 scale, Mtxf *arg1);
 void mtx00015f88(f32 arg0, Mtxf *arg1);
 u32 mtxGetObfuscatedRomBase(void);
-void mtx00016054(Mtxf *mtx, Mtxf *arg1);
+void mtxF2L(Mtxf *src, Mtxf *dst);
 void mtx00016110(f32 mtx1[3][3], f32 mtx2[3][3]);
 void mtx00016140(f32 mtx1[3][3], f32 mtx2[3][3], f32 dst[3][3]);
 void mtx000161b0(f32 arg0[3][3], f32 src[3], f32 dest[3]);
diff --git a/src/include/types.h b/src/include/types.h
index cb6fdc11f..2a2fdd033 100644
--- a/src/include/types.h
+++ b/src/include/types.h
@@ -3597,7 +3597,7 @@ struct room {
 	/*0x0a*/ u16 lightindex; // index of start of this room's lights in data file
 	/*0x0c*/ u16 firstwaypoint; // offset into g_Vars.waypoints
 	/*0x0e*/ s16 roomportallistoffset;
-	/*0x10*/ s16 unk10;
+	/*0x10*/ s16 roommtxindex;
 	/*0x14*/ struct roomgfxdata *gfxdata;
 	/*0x18*/ f32 bbmin[3];
 	/*0x24*/ f32 bbmax[3];
diff --git a/src/lib/mtxasm.s b/src/lib/mtxasm.s
index 4b9eb4b24..1e10d9ccb 100644
--- a/src/lib/mtxasm.s
+++ b/src/lib/mtxasm.s
@@ -500,7 +500,7 @@ glabel mtxGetObfuscatedRomBase
 	jr     $ra
 	addiu  $sp, $sp, 0x20
 
-glabel mtx00016054
+glabel mtxF2L
 	lui    $t2, %hi(var8005ef10)
 	addiu  $t2, $t2, %lo(var8005ef10)
 	addiu  $t0, $zero, 0x4
diff --git a/src/lib/mtxc.c b/src/lib/mtxc.c
index caa52d64d..cc0529b75 100644
--- a/src/lib/mtxc.c
+++ b/src/lib/mtxc.c
@@ -314,7 +314,7 @@ u32 mtxGetObfuscatedRomBase(void)
 	return value;
 }
 
-void mtx00016054(Mtxf *src, Mtxf *dst)
+void mtxF2L(Mtxf *src, Mtxf *dst)
 {
 	u32 src00 = (s32) (src->m[0][0] * var8005ef10[0]);
 	u32 src01 = (s32) (src->m[0][1] * var8005ef10[0]);