Documentation pass on WaterBox code (#1860)

* Documentation pass on WaterBox code

* format

* vtx flags, fix comments

* format

* Add function documentation comment

50 files changed, 285 insertions, 225 deletions

diff --git a/src/code/z_actor.c b/src/code/z_actor.c
index 73a292d41..8fde0ed4a 100644
--- a/src/code/z_actor.c
+++ b/src/code/z_actor.c
@@ -1729,7 +1729,8 @@ void Actor_UpdateBgCheckInfo(PlayState* play, Actor* actor, f32 wallCheckHeight,
         func_800B7678(play, actor, &pos, updBgCheckInfoFlags);
         y = actor->world.pos.y;
 
-        if (WaterBox_GetSurface1(play, &play->colCtx, actor->world.pos.x, actor->world.pos.z, &y, &waterbox)) {
+        if (BgCheck_GetWaterSurfaceNoBgIdAlt(play, &play->colCtx, actor->world.pos.x, actor->world.pos.z, &y,
+                                             &waterbox)) {
             actor->depthInWater = y - actor->world.pos.y;
             if (actor->depthInWater <= 0.0f) {
                 actor->bgCheckFlags &= ~(BGCHECKFLAG_WATER | BGCHECKFLAG_WATER_TOUCH);
@@ -1759,7 +1760,8 @@ void Actor_UpdateBgCheckInfo(PlayState* play, Actor* actor, f32 wallCheckHeight,
         WaterBox* waterbox;
         f32 y = actor->world.pos.y;
 
-        if (WaterBox_GetSurface1(play, &play->colCtx, actor->world.pos.x, actor->world.pos.z, &y, &waterbox)) {
+        if (BgCheck_GetWaterSurfaceNoBgIdAlt(play, &play->colCtx, actor->world.pos.x, actor->world.pos.z, &y,
+                                             &waterbox)) {
             actor->depthInWater = y - actor->world.pos.y;
 
             if (actor->depthInWater < 0.0f) {
diff --git a/src/code/z_bgcheck.c b/src/code/z_bgcheck.c
index 4271927fb..c24c8e0dc 100644
--- a/src/code/z_bgcheck.c
+++ b/src/code/z_bgcheck.c
@@ -561,8 +561,8 @@ f32 BgCheck_RaycastFloorStaticList(CollisionContext* colCtx, u16 xpFlags, SSList
 
         if (((flags & 1) && (colPoly->normal.y < 0)) ||
             ((arg9 & 0x20) && ((colCtx->colHeader->surfaceTypeList[colPoly->type].data[0] >> 0x1E) & 1)) ||
-            COLPOLY_VIA_FLAG_TEST(colPoly->flags_vIA, xpFlags) ||
-            (COLPOLY_VIA_FLAG_TEST(colPoly->flags_vIB, 4) &&
+            COLPOLY_VTX_CHECK_FLAGS_ANY(colPoly->flags_vIA, xpFlags) ||
+            (COLPOLY_VTX_CHECK_FLAGS_ANY(colPoly->flags_vIB, COLPOLY_VIB_FLAG_4) &&
              (((actor != NULL) && (actor->category != ACTORCAT_PLAYER)) ||
               ((actor == NULL) && (xpFlags != COLPOLY_IGNORE_CAMERA))))) {
             if (curNode->next == SS_NULL) {
@@ -712,8 +712,8 @@ s32 BgCheck_SphVsStaticWall(StaticLookup* lookup, CollisionContext* colCtx, u16
         nz = COLPOLY_GET_NORMAL(curPoly->normal.z);
         normalXZ = sqrtf(SQ(nx) + SQ(nz));
         planeDist = Math3D_DistPlaneToPos(nx, ny, nz, curPoly->dist, &resultPos);
-        if (radius < fabsf(planeDist) || COLPOLY_VIA_FLAG_TEST(curPoly->flags_vIA, xpFlags) ||
-            (COLPOLY_VIA_FLAG_TEST(curPoly->flags_vIB, 4) &&
+        if (radius < fabsf(planeDist) || COLPOLY_VTX_CHECK_FLAGS_ANY(curPoly->flags_vIA, xpFlags) ||
+            (COLPOLY_VTX_CHECK_FLAGS_ANY(curPoly->flags_vIB, COLPOLY_VIB_FLAG_4) &&
              (((actor != NULL) && (actor->category != ACTORCAT_PLAYER)) ||
               ((actor == NULL) && (xpFlags != COLPOLY_IGNORE_CAMERA))))) {
             if (curNode->next == SS_NULL) {
@@ -800,8 +800,8 @@ s32 BgCheck_SphVsStaticWall(StaticLookup* lookup, CollisionContext* colCtx, u16
         nz = COLPOLY_GET_NORMAL(curPoly->normal.z);
         normalXZ = sqrtf(SQ(nx) + SQ(nz));
         planeDist = Math3D_DistPlaneToPos(nx, ny, nz, curPoly->dist, &resultPos);
-        if (radius < fabsf(planeDist) || COLPOLY_VIA_FLAG_TEST(curPoly->flags_vIA, xpFlags) ||
-            (COLPOLY_VIA_FLAG_TEST(curPoly->flags_vIB, 4) &&
+        if (radius < fabsf(planeDist) || COLPOLY_VTX_CHECK_FLAGS_ANY(curPoly->flags_vIA, xpFlags) ||
+            (COLPOLY_VTX_CHECK_FLAGS_ANY(curPoly->flags_vIB, COLPOLY_VIB_FLAG_4) &&
              (((actor != NULL) && (actor->category != ACTORCAT_PLAYER)) ||
               ((actor == NULL) && (xpFlags != COLPOLY_IGNORE_CAMERA))))) {
             if (curNode->next == SS_NULL) {
@@ -907,8 +907,8 @@ s32 BgCheck_CheckStaticCeiling(StaticLookup* lookup, u16 xpFlags, CollisionConte
 
         curPolyId = curNode->polyId;
         curPoly = &polyList[curPolyId];
-        if (COLPOLY_VIA_FLAG_TEST(colCtx->colHeader->polyList[curPolyId].flags_vIA, xpFlags) ||
-            (COLPOLY_VIA_FLAG_TEST(colCtx->colHeader->polyList[curPolyId].flags_vIB, 4) &&
+        if (COLPOLY_VTX_CHECK_FLAGS_ANY(colCtx->colHeader->polyList[curPolyId].flags_vIA, xpFlags) ||
+            (COLPOLY_VTX_CHECK_FLAGS_ANY(colCtx->colHeader->polyList[curPolyId].flags_vIB, COLPOLY_VIB_FLAG_4) &&
              (((actor != NULL) && (actor->category != ACTORCAT_PLAYER)) ||
               ((actor == NULL) && (xpFlags != COLPOLY_IGNORE_CAMERA))))) {
             if (curNode->next == SS_NULL) {
@@ -976,9 +976,9 @@ s32 BgCheck_CheckLineAgainstSSList(StaticLineTest* arg0) {
         checkedPoly = &arg0->colCtx->polyNodes.polyCheckTbl[polyId];
 
         if ((*checkedPoly == true) ||
-            ((arg0->xpFlags2 != 0) && !COLPOLY_VIA_FLAG_TEST(test.poly->flags_vIA, arg0->xpFlags2)) ||
-            COLPOLY_VIA_FLAG_TEST(test.poly->flags_vIA, arg0->xpFlags1) ||
-            (COLPOLY_VIA_FLAG_TEST(test.poly->flags_vIB, 4) &&
+            ((arg0->xpFlags2 != 0) && !COLPOLY_VTX_CHECK_FLAGS_ANY(test.poly->flags_vIA, arg0->xpFlags2)) ||
+            COLPOLY_VTX_CHECK_FLAGS_ANY(test.poly->flags_vIA, arg0->xpFlags1) ||
+            (COLPOLY_VTX_CHECK_FLAGS_ANY(test.poly->flags_vIB, COLPOLY_VIB_FLAG_4) &&
              (((arg0->actor != NULL) && (arg0->actor->category != ACTORCAT_PLAYER)) ||
               ((arg0->actor == NULL) && (arg0->xpFlags1 != COLPOLY_IGNORE_CAMERA))))) {
             if (curNode->next == SS_NULL) {
@@ -1063,8 +1063,8 @@ s32 BgCheck_SphVsFirstStaticPolyList(SSNode* node, u16 xpFlags, CollisionContext
     while (true) {
         curPolyId = node->polyId;
         curPoly = &polyList[curPolyId];
-        if (COLPOLY_VIA_FLAG_TEST(colCtx->colHeader->polyList[curPolyId].flags_vIA, xpFlags) ||
-            (COLPOLY_VIA_FLAG_TEST(colCtx->colHeader->polyList[curPolyId].flags_vIB, 4) &&
+        if (COLPOLY_VTX_CHECK_FLAGS_ANY(colCtx->colHeader->polyList[curPolyId].flags_vIA, xpFlags) ||
+            (COLPOLY_VTX_CHECK_FLAGS_ANY(colCtx->colHeader->polyList[curPolyId].flags_vIB, COLPOLY_VIB_FLAG_4) &&
              (((actor != NULL) && (actor->category != ACTORCAT_PLAYER)) ||
               ((actor == NULL) && (xpFlags != COLPOLY_IGNORE_CAMERA))))) {
             if (node->next != SS_NULL) {
@@ -2999,8 +2999,8 @@ void DynaPoly_AddBgActorToLookup(PlayState* play, DynaCollisionContext* dyna, s3
             vIB = (COLPOLY_VTX_INDEX(newPoly->flags_vIB) + *vtxStartIndex);
             vIC = newPoly->vIC + *vtxStartIndex;
 
-            newPoly->flags_vIA = vIA | (newPoly->flags_vIA & 0xE000);
-            newPoly->flags_vIB = vIB | (newPoly->flags_vIB & 0xE000);
+            newPoly->flags_vIA = vIA | COLPOLY_VTX_FLAGS_MASKED(newPoly->flags_vIA);
+            newPoly->flags_vIB = vIB | COLPOLY_VTX_FLAGS_MASKED(newPoly->flags_vIB);
             newPoly->vIC = vIC;
             dVtxList = dyna->vtxList;
             vtxA.x = dVtxList[vIA].x;
@@ -3187,8 +3187,8 @@ f32 BgCheck_RaycastFloorDynaList(DynaRaycast* dynaRaycast, u32 listType) {
 
     while (true) {
         id = curNode->polyId;
-        if (COLPOLY_VIA_FLAG_TEST(polyList[id].flags_vIA, dynaRaycast->xpFlags) ||
-            (COLPOLY_VIA_FLAG_TEST(polyList[id].flags_vIB, 4) &&
+        if (COLPOLY_VTX_CHECK_FLAGS_ANY(polyList[id].flags_vIA, dynaRaycast->xpFlags) ||
+            (COLPOLY_VTX_CHECK_FLAGS_ANY(polyList[id].flags_vIB, COLPOLY_VIB_FLAG_4) &&
              (((dynaRaycast->actor != NULL) && (dynaRaycast->actor->category != ACTORCAT_PLAYER)) ||
               ((dynaRaycast->actor == NULL) && (dynaRaycast->xpFlags != COLPOLY_IGNORE_CAMERA)))) ||
             ((dynaRaycast->unk_24 & 0x20) &&
@@ -3394,9 +3394,10 @@ s32 BgCheck_SphVsDynaWallInBgActor(CollisionContext* colCtx, u16 xpFlags, DynaCo
         normalXZ = sqrtf(SQ(nx) + SQ(nz));
 
         planeDist = Math3D_DistPlaneToPos(nx, ny, nz, poly->dist, &resultPos);
-        if (radius < fabsf(planeDist) || COLPOLY_VIA_FLAG_TEST(poly->flags_vIA, xpFlags) ||
-            (COLPOLY_VIA_FLAG_TEST(poly->flags_vIB, 4) && (((actor != NULL) && (actor->category != ACTORCAT_PLAYER)) ||
-                                                           ((actor == NULL) && (xpFlags != COLPOLY_IGNORE_CAMERA))))) {
+        if (radius < fabsf(planeDist) || COLPOLY_VTX_CHECK_FLAGS_ANY(poly->flags_vIA, xpFlags) ||
+            (COLPOLY_VTX_CHECK_FLAGS_ANY(poly->flags_vIB, COLPOLY_VIB_FLAG_4) &&
+             (((actor != NULL) && (actor->category != ACTORCAT_PLAYER)) ||
+              ((actor == NULL) && (xpFlags != COLPOLY_IGNORE_CAMERA))))) {
             if (curNode->next == SS_NULL) {
                 break;
             } else {
@@ -3470,9 +3471,10 @@ s32 BgCheck_SphVsDynaWallInBgActor(CollisionContext* colCtx, u16 xpFlags, DynaCo
         normalXZ = sqrtf(SQ(nx) + SQ(nz));
 
         planeDist = Math3D_DistPlaneToPos(nx, ny, nz, poly->dist, &resultPos);
-        if (radius < fabsf(planeDist) || COLPOLY_VIA_FLAG_TEST(poly->flags_vIA, xpFlags) ||
-            (COLPOLY_VIA_FLAG_TEST(poly->flags_vIB, 4) && (((actor != NULL) && (actor->category != ACTORCAT_PLAYER)) ||
-                                                           ((actor == NULL) && (xpFlags != COLPOLY_IGNORE_CAMERA))))) {
+        if (radius < fabsf(planeDist) || COLPOLY_VTX_CHECK_FLAGS_ANY(poly->flags_vIA, xpFlags) ||
+            (COLPOLY_VTX_CHECK_FLAGS_ANY(poly->flags_vIB, COLPOLY_VIB_FLAG_4) &&
+             (((actor != NULL) && (actor->category != ACTORCAT_PLAYER)) ||
+              ((actor == NULL) && (xpFlags != COLPOLY_IGNORE_CAMERA))))) {
             if (curNode->next == SS_NULL) {
                 break;
             } else {
@@ -3630,9 +3632,10 @@ s32 BgCheck_CheckDynaCeilingList(CollisionContext* colCtx, u16 xpFlags, DynaColl
     while (true) {
         polyId = curNode->polyId;
         poly = &dyna->polyList[polyId];
-        if (COLPOLY_VIA_FLAG_TEST(poly->flags_vIA, xpFlags) ||
-            (COLPOLY_VIA_FLAG_TEST(poly->flags_vIB, 4) && (((actor != NULL) && (actor->category != ACTORCAT_PLAYER)) ||
-                                                           ((actor == NULL) && (xpFlags != COLPOLY_IGNORE_CAMERA))))) {
+        if (COLPOLY_VTX_CHECK_FLAGS_ANY(poly->flags_vIA, xpFlags) ||
+            (COLPOLY_VTX_CHECK_FLAGS_ANY(poly->flags_vIB, COLPOLY_VIB_FLAG_4) &&
+             (((actor != NULL) && (actor->category != ACTORCAT_PLAYER)) ||
+              ((actor == NULL) && (xpFlags != COLPOLY_IGNORE_CAMERA))))) {
             if (curNode->next == SS_NULL) {
                 break;
             } else {
@@ -3738,8 +3741,8 @@ s32 BgCheck_CheckLineAgainstBgActorSSList(DynaLineTest* dynaLineTest) {
     while (true) {
         polyId = curNode->polyId;
         test.poly = &dynaLineTest->dyna->polyList[polyId];
-        if (COLPOLY_VIA_FLAG_TEST(test.poly->flags_vIA, dynaLineTest->xpFlags) ||
-            (COLPOLY_VIA_FLAG_TEST(test.poly->flags_vIB, 4) &&
+        if (COLPOLY_VTX_CHECK_FLAGS_ANY(test.poly->flags_vIA, dynaLineTest->xpFlags) ||
+            (COLPOLY_VTX_CHECK_FLAGS_ANY(test.poly->flags_vIB, COLPOLY_VIB_FLAG_4) &&
              (((dynaLineTest->actor != NULL) && (dynaLineTest->actor->category != ACTORCAT_PLAYER)) ||
               ((dynaLineTest->actor == NULL) && (dynaLineTest->xpFlags != COLPOLY_IGNORE_CAMERA))))) {
             if (curNode->next == SS_NULL) {
@@ -3878,8 +3881,8 @@ s32 BgCheck_SphVsFirstDynaPolyList(CollisionContext* colCtx, u16 xpFlags, Collis
     while (true) {
         curPolyId = curNode->polyId;
         curPoly = &dyna->polyList[curPolyId];
-        if (COLPOLY_VIA_FLAG_TEST(curPoly->flags_vIA, xpFlags) ||
-            (COLPOLY_VIA_FLAG_TEST(curPoly->flags_vIB, 4) &&
+        if (COLPOLY_VTX_CHECK_FLAGS_ANY(curPoly->flags_vIA, xpFlags) ||
+            (COLPOLY_VTX_CHECK_FLAGS_ANY(curPoly->flags_vIB, COLPOLY_VIB_FLAG_4) &&
              (((actor != NULL) && (actor->category != ACTORCAT_PLAYER)) ||
               ((actor == NULL) && (xpFlags != COLPOLY_IGNORE_CAMERA))))) {
             if (curNode->next == SS_NULL) {
@@ -4308,17 +4311,22 @@ s32 SurfaceType_IsFloorConveyor(CollisionContext* colCtx, CollisionPoly* poly, s
     if (poly == NULL) {
         return false;
     }
-    flags = poly->flags_vIB & 0x2000;
+    flags = COLPOLY_VTX_CHECK_FLAGS_ANY(poly->flags_vIB, COLPOLY_IS_FLOOR_CONVEYOR);
     return !!flags;
 }
 
-s32 func_800C9DDC(CollisionContext* colCtx, CollisionPoly* poly, s32 bgId) {
+/**
+ * Checks if poly is a dive spot for Deku Link
+ *
+ * Returns true if the floor is a dive spot, else false
+ */
+s32 SurfaceType_IsFloorDekuFlower(CollisionContext* colCtx, CollisionPoly* poly, s32 bgId) {
     u32 flags;
 
     if (BgCheck_GetCollisionHeader(colCtx, bgId) == NULL) {
         return true;
     }
-    flags = poly->flags_vIB & 0x4000;
+    flags = COLPOLY_VTX_CHECK_FLAGS_ANY(poly->flags_vIB, COLPOLY_IS_FLOOR_DEKU_FLOWER);
     return !!flags;
 }
 
@@ -4345,35 +4353,43 @@ u32 SurfaceType_IsWallDamage(CollisionContext* colCtx, CollisionPoly* poly, s32
 }
 
 /**
- * Internal. Get the water surface at point (`x`, `ySurface`, `z`). `ySurface` doubles as position y input
- * returns true if point is within the xz boundaries of an active water box, else false
- * `ySurface` returns the water box's surface, while `outWaterBox` returns a pointer to the WaterBox
+ * Get the water surface at point (`x`, `z`).
+ * returns true if point is within the xz boundaries of an active WaterBox, else false
+ * `outWaterSurface` returns the WaterBox's surface
+ * `outWaterBox` returns a pointer to the WaterBox
+ * `outBgId` returns the owner of the WaterBox
+ *
+ * The search performed assumes waterboxes cannot overlap, as water has effectively infinite depth
  */
-s32 WaterBox_GetSurfaceImpl(PlayState* play, CollisionContext* colCtx, f32 x, f32 z, f32* ySurface,
-                            WaterBox** outWaterBox, s32* bgId) {
+s32 BgCheck_GetWaterSurface(PlayState* play, CollisionContext* colCtx, f32 x, f32 z, f32* outWaterSurface,
+                            WaterBox** outWaterBox, s32* outBgId) {
     CollisionHeader* colHeader;
     s32 room;
     s32 i;
     WaterBox* curWaterBox;
     BgActor* bgActor;
 
-    *bgId = BGCHECK_SCENE;
+    *outBgId = BGCHECK_SCENE;
     colHeader = colCtx->colHeader;
 
     if ((colHeader->numWaterBoxes != 0) && (colHeader->waterBoxes != NULL)) {
         for (curWaterBox = colHeader->waterBoxes; curWaterBox < colHeader->waterBoxes + colHeader->numWaterBoxes;
              curWaterBox++) {
-            room = 0x3F & (curWaterBox->properties >> 13);
-            if ((room == play->roomCtx.curRoom.num) || (room == 0x3F)) {
-                if (curWaterBox->properties & 0x80000) {
-                    continue;
-                }
-                if ((curWaterBox->minPos.x < x) && (x < curWaterBox->minPos.x + curWaterBox->xLength)) {
-                    if ((curWaterBox->minPos.z < z) && (z < curWaterBox->minPos.z + curWaterBox->zLength)) {
-                        *outWaterBox = curWaterBox;
-                        *ySurface = curWaterBox->minPos.y;
-                        return true;
-                    }
+            room = (s32)WATERBOX_ROOM(curWaterBox->properties);
+            if ((room != play->roomCtx.curRoom.num) && (room != WATERBOX_ROOM_ALL)) {
+                continue;
+            }
+            if (curWaterBox->properties & WATERBOX_IS_DISABLED) {
+                continue;
+            }
+            //! @bug: WaterBox bounds check issue. This range check excludes all points falling exactly on the border of
+            //! the WaterBox. Thus, when two waterboxes are flush against each other, a seam will exist between them
+            //! where no water is detected.
+            if ((curWaterBox->minPos.x < x) && (x < curWaterBox->minPos.x + curWaterBox->xLength)) {
+                if ((curWaterBox->minPos.z < z) && (z < curWaterBox->minPos.z + curWaterBox->zLength)) {
+                    *outWaterBox = curWaterBox;
+                    *outWaterSurface = curWaterBox->minPos.y;
+                    return true;
                 }
             }
         }
@@ -4390,14 +4406,15 @@ s32 WaterBox_GetSurfaceImpl(PlayState* play, CollisionContext* colCtx, f32 x, f3
                  curWaterBox <
                  colCtx->dyna.waterBoxList.boxes + bgActor->waterboxesStartIndex + bgActor->colHeader->numWaterBoxes;
                  curWaterBox++) {
-                if (curWaterBox->properties & 0x80000) {
+                if (curWaterBox->properties & WATERBOX_IS_DISABLED) {
                     continue;
                 }
+                //! @bug: WaterBox bounds check issue.
                 if ((curWaterBox->minPos.x < x) && (x < curWaterBox->minPos.x + curWaterBox->xLength)) {
                     if ((curWaterBox->minPos.z < z) && (z < curWaterBox->minPos.z + curWaterBox->zLength)) {
                         *outWaterBox = curWaterBox;
-                        *ySurface = curWaterBox->minPos.y;
-                        *bgId = i;
+                        *outWaterSurface = curWaterBox->minPos.y;
+                        *outBgId = i;
                         return true;
                     }
                 }
@@ -4407,34 +4424,49 @@ s32 WaterBox_GetSurfaceImpl(PlayState* play, CollisionContext* colCtx, f32 x, f3
     return false;
 }
 
-// boolean
-s32 WaterBox_GetSurface1(PlayState* play, CollisionContext* colCtx, f32 x, f32 z, f32* ySurface,
-                         WaterBox** outWaterBox) {
-    return WaterBox_GetSurface1_2(play, colCtx, x, z, ySurface, outWaterBox);
+/**
+ * Get the water surface at point (`x`, `z`).
+ * returns true if point is within the xz boundaries of an active WaterBox, else false
+ * `outWaterSurface` returns the WaterBox's surface
+ * `outWaterBox` returns a pointer to the WaterBox
+ *
+ * The search performed assumes waterboxes cannot overlap, as water has effectively infinite depth
+ */
+s32 BgCheck_GetWaterSurfaceNoBgIdAlt(PlayState* play, CollisionContext* colCtx, f32 x, f32 z, f32* outWaterSurface,
+                                     WaterBox** outWaterBox) {
+    return BgCheck_GetWaterSurfaceNoBgId(play, colCtx, x, z, outWaterSurface, outWaterBox);
 }
 
-// boolean
-s32 WaterBox_GetSurface1_2(PlayState* play, CollisionContext* colCtx, f32 x, f32 z, f32* ySurface,
-                           WaterBox** outWaterBox) {
+/**
+ * Get the water surface at point (`x`, `z`).
+ * returns true if point is within the xz boundaries of an active WaterBox, else false
+ * `outWaterSurface` returns the WaterBox's surface
+ * `outWaterBox` returns a pointer to the WaterBox
+ *
+ * The search performed assumes waterboxes cannot overlap, as water has effectively infinite depth
+ */
+s32 BgCheck_GetWaterSurfaceNoBgId(PlayState* play, CollisionContext* colCtx, f32 x, f32 z, f32* outWaterSurface,
+                                  WaterBox** outWaterBox) {
     s32 bgId;
-    return WaterBox_GetSurfaceImpl(play, colCtx, x, z, ySurface, outWaterBox, &bgId);
+    return BgCheck_GetWaterSurface(play, colCtx, x, z, outWaterSurface, outWaterBox, &bgId);
 }
 
 /**
- * Gets the first active WaterBox at `pos` where WaterBox.properties & 0x80000 == 0
+ * Gets the first active WaterBox at `pos`
  * `surfaceCheckDist` is the absolute y distance from the water surface to check
- * returns the index of the waterbox found, or -1 if no waterbox is found
- * `outWaterBox` returns the pointer to the waterbox found, or NULL if none is found
+ * returns the index of the WaterBox found, or -1 if no WaterBox is found
+ * `outWaterBox` returns the pointer to the WaterBox found, or NULL if none is found
+ * `outBgId` returns the owner of the WaterBox
  */
-s32 WaterBox_GetSurface2(PlayState* play, CollisionContext* colCtx, Vec3f* pos, f32 surfaceCheckDist,
-                         WaterBox** outWaterBox, s32* bgId) {
+s32 BgCheck_FindWaterBox(PlayState* play, CollisionContext* colCtx, Vec3f* pos, f32 surfaceCheckDist,
+                         WaterBox** outWaterBox, s32* outBgId) {
     CollisionHeader* colHeader;
     s32 room;
     s32 i;
     WaterBox* waterBox;
     BgActor* bgActor;
 
-    *bgId = BGCHECK_SCENE;
+    *outBgId = BGCHECK_SCENE;
     colHeader = colCtx->colHeader;
 
     //! @bug: check skips testing BgActor waterboxes
@@ -4446,14 +4478,15 @@ s32 WaterBox_GetSurface2(PlayState* play, CollisionContext* colCtx, Vec3f* pos,
     for (i = 0; i < colHeader->numWaterBoxes; i++) {
         waterBox = &colHeader->waterBoxes[i];
 
-        room = WATERBOX_ROOM(waterBox->properties);
-        if ((room != play->roomCtx.curRoom.num) && (room != 0x3F)) {
+        room = WATERBOX_ROOM((s32)waterBox->properties);
+        if ((room != play->roomCtx.curRoom.num) && (room != WATERBOX_ROOM_ALL)) {
             continue;
         }
-        if ((waterBox->properties & 0x80000)) {
+        if (waterBox->properties & WATERBOX_IS_DISABLED) {
             continue;
         }
-        if (((waterBox->minPos.x < pos->x) && (pos->x < waterBox->minPos.x + waterBox->xLength))) {
+        //! @bug: WaterBox bounds check issue. See BgCheck_GetWaterSurface for more details.
+        if ((waterBox->minPos.x < pos->x) && (pos->x < waterBox->minPos.x + waterBox->xLength)) {
             if ((waterBox->minPos.z < pos->z) && (pos->z < waterBox->minPos.z + waterBox->zLength)) {
                 if ((pos->y - surfaceCheckDist < waterBox->minPos.y) &&
                     (waterBox->minPos.y < pos->y + surfaceCheckDist)) {
@@ -4475,14 +4508,15 @@ s32 WaterBox_GetSurface2(PlayState* play, CollisionContext* colCtx, Vec3f* pos,
              waterBox <
              colCtx->dyna.waterBoxList.boxes + bgActor->waterboxesStartIndex + bgActor->colHeader->numWaterBoxes;
              waterBox++) {
-            if (waterBox->properties & 0x80000) {
+            if (waterBox->properties & WATERBOX_IS_DISABLED) {
                 continue;
             }
+            //! @bug: WaterBox bounds check issue. See BgCheck_GetWaterSurface for more details.
             if ((waterBox->minPos.x < pos->x) && (pos->x < waterBox->minPos.x + waterBox->xLength)) {
                 if ((waterBox->minPos.z < pos->z) && (pos->z < waterBox->minPos.z + waterBox->zLength)) {
                     if ((pos->y - surfaceCheckDist < waterBox->minPos.y) &&
                         (waterBox->minPos.y < pos->y + surfaceCheckDist)) {
-                        *bgId = i;
+                        *outBgId = i;
                         *outWaterBox = waterBox;
                         return i;
                     }
@@ -4495,7 +4529,7 @@ s32 WaterBox_GetSurface2(PlayState* play, CollisionContext* colCtx, Vec3f* pos,
     return -1;
 }
 
-f32 func_800CA568(CollisionContext* colCtx, s32 waterBoxId, s32 bgId) {
+f32 WaterBox_GetSurface(CollisionContext* colCtx, s32 waterBoxId, s32 bgId) {
     CollisionHeader* colHeader;
 
     colHeader = BgCheck_GetCollisionHeader(colCtx, bgId);
@@ -4561,13 +4595,16 @@ u32 WaterBox_GetLightSettingIndex(CollisionContext* colCtx, WaterBox* waterBox)
 }
 
 /**
- * Get the water surface at point (`x`, `ySurface`, `z`). `ySurface` doubles as position y input
- * same as WaterBox_GetSurfaceImpl, but tests if WaterBox properties & 0x80000 != 0
- * returns true if point is within the xz boundaries of an active water box, else false
- * `ySurface` returns the water box's surface, while `outWaterBox` returns a pointer to the WaterBox
+ * Unused. Gets the water surface? at point (`x`, `z`) for disabled? waterboxes only.
+ * returns true if point is within the xz boundaries of a disabled? WaterBox, else false
+ * `outWaterSurface` returns the WaterBox's surface
+ * `outWaterBox` returns a pointer to the WaterBox
+ * `outBgId` returns the WaterBox's owner
+ *
+ * The search performed assumes waterboxes cannot overlap.
  */
-s32 func_800CA6F0(PlayState* play, CollisionContext* colCtx, f32 x, f32 z, f32* ySurface, WaterBox** outWaterBox,
-                  s32* bgId) {
+s32 func_800CA6F0(PlayState* play, CollisionContext* colCtx, f32 x, f32 z, f32* outWaterSurface, WaterBox** outWaterBox,
+                  s32* outBgId) {
     CollisionHeader* colHeader;
     s32 i;
     WaterBox* curWaterBox;
@@ -4575,26 +4612,28 @@ s32 func_800CA6F0(PlayState* play, CollisionContext* colCtx, f32 x, f32 z, f32*
     s32 room;
 
     *outWaterBox = NULL;
-    *bgId = BGCHECK_SCENE;
+    *outBgId = BGCHECK_SCENE;
     colHeader = colCtx->colHeader;
 
+    //! @bug: check skips testing BgActor waterboxes
     if ((colHeader->numWaterBoxes == 0) || (colHeader->waterBoxes == NULL)) {
         return false;
     }
     for (curWaterBox = colHeader->waterBoxes; curWaterBox < colHeader->waterBoxes + colHeader->numWaterBoxes;
          curWaterBox++) {
-        room = WATERBOX_ROOM(curWaterBox->properties);
+        room = WATERBOX_ROOM((s32)curWaterBox->properties);
 
-        if ((room != play->roomCtx.curRoom.num) && (room != 0x3F)) {
+        if ((room != play->roomCtx.curRoom.num) && (room != WATERBOX_ROOM_ALL)) {
             continue;
         }
-        if (!(curWaterBox->properties & 0x80000)) {
+        if (!(curWaterBox->properties & WATERBOX_IS_DISABLED)) {
             continue;
         }
+        //! @bug: WaterBox bounds check issue. See BgCheck_GetWaterSurface for more details.
         if ((curWaterBox->minPos.x < x) && (x < curWaterBox->minPos.x + curWaterBox->xLength)) {
             if ((curWaterBox->minPos.z < z) && (z < curWaterBox->minPos.z + curWaterBox->zLength)) {
                 *outWaterBox = curWaterBox;
-                *ySurface = curWaterBox->minPos.y;
+                *outWaterSurface = curWaterBox->minPos.y;
                 return true;
             }
         }
@@ -4609,14 +4648,15 @@ s32 func_800CA6F0(PlayState* play, CollisionContext* colCtx, f32 x, f32 z, f32*
              curWaterBox <
              colCtx->dyna.waterBoxList.boxes + bgActor->waterboxesStartIndex + bgActor->colHeader->numWaterBoxes;
              curWaterBox++) {
-            if (!(curWaterBox->properties & 0x80000)) {
+            if (!(curWaterBox->properties & WATERBOX_IS_DISABLED)) {
                 continue;
             }
+            //! @bug: WaterBox bounds check issue. See BgCheck_GetWaterSurface for more details.
             if ((curWaterBox->minPos.x < x) && (x < curWaterBox->minPos.x + curWaterBox->xLength)) {
                 if ((curWaterBox->minPos.z < z) && (z < curWaterBox->minPos.z + curWaterBox->zLength)) {
                     *outWaterBox = curWaterBox;
-                    *ySurface = curWaterBox->minPos.y;
-                    *bgId = i;
+                    *outWaterSurface = curWaterBox->minPos.y;
+                    *outBgId = i;
                     return true;
                 }
             }
@@ -4625,10 +4665,19 @@ s32 func_800CA6F0(PlayState* play, CollisionContext* colCtx, f32 x, f32 z, f32*
     return false;
 }
 
-s32 func_800CA9D0(PlayState* play, CollisionContext* colCtx, f32 x, f32 z, f32* ySurface, WaterBox** outWaterBox) {
+/**
+ * Unused. Gets the water surface? at point (`x`, `z`) for disabled? waterboxes only.
+ * returns true if point is within the xz boundaries of a disabled? WaterBox, else false
+ * `outWaterSurface` returns the WaterBox's surface
+ * `outWaterBox` returns a pointer to the WaterBox
+ *
+ * The search performed assumes waterboxes cannot overlap.
+ */
+s32 func_800CA9D0(PlayState* play, CollisionContext* colCtx, f32 x, f32 z, f32* outWaterSurface,
+                  WaterBox** outWaterBox) {
     s32 bgId;
 
-    return func_800CA6F0(play, colCtx, x, z, ySurface, outWaterBox, &bgId);
+    return func_800CA6F0(play, colCtx, x, z, outWaterSurface, outWaterBox, &bgId);
 }
 
 /**
diff --git a/src/code/z_camera.c b/src/code/z_camera.c
index fb732b65e..57cc02e5c 100644
--- a/src/code/z_camera.c
+++ b/src/code/z_camera.c
@@ -820,7 +820,7 @@ s32 Camera_GetWaterBoxBgCamSetting(Camera* camera, f32* waterY) {
     playerPosShape = Actor_GetWorldPosShapeRot(camera->focalActor);
     *waterY = playerPosShape.pos.y;
 
-    if (!WaterBox_GetSurfaceImpl(camera->play, &camera->play->colCtx, playerPosShape.pos.x, playerPosShape.pos.z,
+    if (!BgCheck_GetWaterSurface(camera->play, &camera->play->colCtx, playerPosShape.pos.x, playerPosShape.pos.z,
                                  waterY, &waterBox, &bgId)) {
         // player's position is not in a waterbox
         *waterY = playerPosShape.pos.y;
diff --git a/src/code/z_fireobj.c b/src/code/z_fireobj.c
index fea019079..a3274b9f3 100644
--- a/src/code/z_fireobj.c
+++ b/src/code/z_fireobj.c
@@ -108,7 +108,7 @@ void FireObj_UpdateStateTransitions(PlayState* play, FireObj* fire) {
     }
 
     if ((fire->flags & FIRE_FLAG_WATER_EXTINGUISHABLE) && (fire->state != FIRE_STATE_NOT_LIT) &&
-        WaterBox_GetSurface1_2(play, &play->colCtx, fire->position.x, fire->position.z, &waterY, &waterBox) &&
+        BgCheck_GetWaterSurfaceNoBgId(play, &play->colCtx, fire->position.x, fire->position.z, &waterY, &waterBox) &&
         ((waterY - fire->position.y) > (6500.0f * fire->yScale))) {
         FireObj_SetState(fire, fire->dynamicSizeStep, FIRE_STATE_NOT_LIT);
     }
diff --git a/src/code/z_kankyo.c b/src/code/z_kankyo.c
index b04139ba8..5e5e288ac 100644
--- a/src/code/z_kankyo.c
+++ b/src/code/z_kankyo.c
@@ -1119,7 +1119,7 @@ void Environment_UpdateSkybox(u8 skyboxId, EnvironmentContext* envCtx, SkyboxCon
 }
 
 void Environment_EnableUnderwaterLights(PlayState* play, s32 waterLightsIndex) {
-    if (waterLightsIndex == 0x1F) {
+    if (waterLightsIndex == WATERBOX_LIGHT_INDEX_NONE) {
         waterLightsIndex = 0;
     }
 
diff --git a/src/code/z_play.c b/src/code/z_play.c
index 01f25afaf..dc076fcc2 100644
--- a/src/code/z_play.c
+++ b/src/code/z_play.c
@@ -499,7 +499,7 @@ f32 Play_GetWaterSurface(PlayState* this, Vec3f* pos, s32* lightIndex) {
     WaterBox* waterBox;
     s32 bgId;
 
-    if (!WaterBox_GetSurfaceImpl(this, &this->colCtx, pos->x, pos->z, &waterSurfaceY, &waterBox, &bgId)) {
+    if (!BgCheck_GetWaterSurface(this, &this->colCtx, pos->x, pos->z, &waterSurfaceY, &waterBox, &bgId)) {
         return BGCHECK_Y_MIN;
     }
 
@@ -1998,8 +1998,8 @@ s32 Play_IsUnderwater(PlayState* this, Vec3f* pos) {
 
     waterSurfacePos = *pos;
 
-    if ((WaterBox_GetSurface1(this, &this->colCtx, waterSurfacePos.x, waterSurfacePos.z, &waterSurfacePos.y,
-                              &waterBox) == true) &&
+    if ((BgCheck_GetWaterSurfaceNoBgIdAlt(this, &this->colCtx, waterSurfacePos.x, waterSurfacePos.z, &waterSurfacePos.y,
+                                          &waterBox) == true) &&
         (pos->y < waterSurfacePos.y) &&
         (BgCheck_EntityRaycastFloor3(&this->colCtx, &poly, &bgId, &waterSurfacePos) != BGCHECK_Y_MIN)) {
         return true;
diff --git a/src/overlays/actors/ovl_Bg_Dblue_Balance/z_bg_dblue_balance.c b/src/overlays/actors/ovl_Bg_Dblue_Balance/z_bg_dblue_balance.c
index a1fa4b52e..9d97123d6 100644
--- a/src/overlays/actors/ovl_Bg_Dblue_Balance/z_bg_dblue_balance.c
+++ b/src/overlays/actors/ovl_Bg_Dblue_Balance/z_bg_dblue_balance.c
@@ -172,12 +172,12 @@ s32 func_80B82454(BgDblueBalance* this, PlayState* play) {
 void func_80B8259C(BgDblueBalance* this, PlayState* play) {
     s32 pad;
     WaterBox* waterBox;
-    f32 sp2C;
+    f32 waterSurface;
 
-    if (WaterBox_GetSurface1_2(play, &play->colCtx, this->dyna.actor.world.pos.x, this->dyna.actor.world.pos.z, &sp2C,
-                               &waterBox)) {
-        this->dyna.actor.depthInWater = sp2C - this->dyna.actor.world.pos.y;
-        this->unk_228 = sp2C;
+    if (BgCheck_GetWaterSurfaceNoBgId(play, &play->colCtx, this->dyna.actor.world.pos.x, this->dyna.actor.world.pos.z,
+                                      &waterSurface, &waterBox)) {
+        this->dyna.actor.depthInWater = waterSurface - this->dyna.actor.world.pos.y;
+        this->unk_228 = waterSurface;
         if ((this->dyna.actor.depthInWater < 150.0f) && (this->dyna.actor.depthInWater > -150.0f)) {
             this->unk_182 = true;
         } else {
diff --git a/src/overlays/actors/ovl_Bg_Dblue_Elevator/z_bg_dblue_elevator.c b/src/overlays/actors/ovl_Bg_Dblue_Elevator/z_bg_dblue_elevator.c
index 7f836fb6a..8f0d1bfb1 100644
--- a/src/overlays/actors/ovl_Bg_Dblue_Elevator/z_bg_dblue_elevator.c
+++ b/src/overlays/actors/ovl_Bg_Dblue_Elevator/z_bg_dblue_elevator.c
@@ -63,7 +63,7 @@ void BgDblueElevator_CheckWaterBoxInfo(BgDblueElevator* this, PlayState* play2)
     s32 bgId;
 
     this->isWithinWaterBoxXZ =
-        WaterBox_GetSurfaceImpl(play, &play->colCtx, this->dyna.actor.world.pos.x, this->dyna.actor.world.pos.z,
+        BgCheck_GetWaterSurface(play, &play->colCtx, this->dyna.actor.world.pos.x, this->dyna.actor.world.pos.z,
                                 &this->waterSurfacePosY, &waterBox, &bgId);
 }
 
diff --git a/src/overlays/actors/ovl_Bg_Dblue_Waterfall/z_bg_dblue_waterfall.c b/src/overlays/actors/ovl_Bg_Dblue_Waterfall/z_bg_dblue_waterfall.c
index 1df2be89c..df7addd78 100644
--- a/src/overlays/actors/ovl_Bg_Dblue_Waterfall/z_bg_dblue_waterfall.c
+++ b/src/overlays/actors/ovl_Bg_Dblue_Waterfall/z_bg_dblue_waterfall.c
@@ -271,14 +271,14 @@ void func_80B84568(BgDblueWaterfall* this, PlayState* play) {
     WaterBox* waterBox;
     s32 bgId;
     f32 sp34 = BgCheck_EntityRaycastFloor5(&play->colCtx, &sp40, &bgId, &this->actor, &this->actor.world.pos);
-    f32 sp30;
+    f32 waterSurface;
 
-    if (WaterBox_GetSurface1_2(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z, &sp30,
-                               &waterBox)) {
-        if (sp30 < sp34) {
+    if (BgCheck_GetWaterSurfaceNoBgId(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z,
+                                      &waterSurface, &waterBox)) {
+        if (waterSurface < sp34) {
             this->unk_198 = sp34;
         } else {
-            this->unk_198 = sp30;
+            this->unk_198 = waterSurface;
         }
     } else {
         this->unk_198 = sp34;
diff --git a/src/overlays/actors/ovl_Bg_Goron_Oyu/z_bg_goron_oyu.c b/src/overlays/actors/ovl_Bg_Goron_Oyu/z_bg_goron_oyu.c
index d66a8216d..9531790c6 100644
--- a/src/overlays/actors/ovl_Bg_Goron_Oyu/z_bg_goron_oyu.c
+++ b/src/overlays/actors/ovl_Bg_Goron_Oyu/z_bg_goron_oyu.c
@@ -98,8 +98,8 @@ void BgGoronOyu_UpdateWaterBoxInfo(BgGoronOyu* this, PlayState* play) {
     WaterBox* waterBox;
     f32 ySurface;
 
-    if (WaterBox_GetSurface1(play, &play->colCtx, this->dyna.actor.world.pos.x, this->dyna.actor.world.pos.z, &ySurface,
-                             &waterBox)) {
+    if (BgCheck_GetWaterSurfaceNoBgIdAlt(play, &play->colCtx, this->dyna.actor.world.pos.x,
+                                         this->dyna.actor.world.pos.z, &ySurface, &waterBox)) {
         Math_Vec3s_ToVec3f(&this->waterBoxPos, &waterBox->minPos);
         this->waterBoxXLength = waterBox->xLength;
         this->waterBoxZLength = waterBox->zLength;
diff --git a/src/overlays/actors/ovl_Bg_Icefloe/z_bg_icefloe.c b/src/overlays/actors/ovl_Bg_Icefloe/z_bg_icefloe.c
index df88ac783..ca95b7498 100644
--- a/src/overlays/actors/ovl_Bg_Icefloe/z_bg_icefloe.c
+++ b/src/overlays/actors/ovl_Bg_Icefloe/z_bg_icefloe.c
@@ -120,8 +120,8 @@ void func_80AC4C34(BgIcefloe* this, PlayState* play) {
 
     this->timer--;
     if ((this->timer == 0) ||
-        !WaterBox_GetSurface1_2(play, &play->colCtx, this->dyna.actor.world.pos.x, this->dyna.actor.world.pos.z,
-                                &this->dyna.actor.home.pos.y, &waterBox)) {
+        !BgCheck_GetWaterSurfaceNoBgId(play, &play->colCtx, this->dyna.actor.world.pos.x, this->dyna.actor.world.pos.z,
+                                       &this->dyna.actor.home.pos.y, &waterBox)) {
         func_80AC4CF0(this);
     } else {
         this->dyna.actor.world.pos.y =
diff --git a/src/overlays/actors/ovl_Bg_Lotus/z_bg_lotus.c b/src/overlays/actors/ovl_Bg_Lotus/z_bg_lotus.c
index 7115fa8ca..012ff5192 100644
--- a/src/overlays/actors/ovl_Bg_Lotus/z_bg_lotus.c
+++ b/src/overlays/actors/ovl_Bg_Lotus/z_bg_lotus.c
@@ -148,8 +148,8 @@ void BgLotus_Update(Actor* thisx, PlayState* play) {
     s32 pad;
     WaterBox* waterBox;
 
-    WaterBox_GetSurface1_2(play, &play->colCtx, this->dyna.actor.world.pos.x, this->dyna.actor.world.pos.z,
-                           &this->unk160, &waterBox);
+    BgCheck_GetWaterSurfaceNoBgId(play, &play->colCtx, this->dyna.actor.world.pos.x, this->dyna.actor.world.pos.z,
+                                  &this->unk160, &waterBox);
     this->actionFunc(this, play);
 }
 
diff --git a/src/overlays/actors/ovl_En_Arrow/z_en_arrow.c b/src/overlays/actors/ovl_En_Arrow/z_en_arrow.c
index 7fd853d0a..a0f31e1bb 100644
--- a/src/overlays/actors/ovl_En_Arrow/z_en_arrow.c
+++ b/src/overlays/actors/ovl_En_Arrow/z_en_arrow.c
@@ -319,7 +319,8 @@ void func_8088AA98(EnArrow* this, PlayState* play) {
     Vec3f sp44;
     f32 temp_f0;
 
-    if (WaterBox_GetSurface1(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z, &sp50, &waterBox) &&
+    if (BgCheck_GetWaterSurfaceNoBgIdAlt(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z, &sp50,
+                                         &waterBox) &&
         (this->actor.world.pos.y < sp50) && !(this->actor.bgCheckFlags & BGCHECKFLAG_WATER)) {
         this->actor.bgCheckFlags |= BGCHECKFLAG_WATER;
 
diff --git a/src/overlays/actors/ovl_En_Bigokuta/z_en_bigokuta.c b/src/overlays/actors/ovl_En_Bigokuta/z_en_bigokuta.c
index f45b87d03..220e46a4f 100644
--- a/src/overlays/actors/ovl_En_Bigokuta/z_en_bigokuta.c
+++ b/src/overlays/actors/ovl_En_Bigokuta/z_en_bigokuta.c
@@ -189,8 +189,8 @@ s32 EnBigokuta_IsInWater(EnBigokuta* this, PlayState* play) {
 
     this->picto.actor.floorHeight = BgCheck_EntityRaycastFloor5(&play->colCtx, &this->picto.actor.floorPoly, &bgId,
                                                                 &this->picto.actor, &this->picto.actor.world.pos);
-    if (!WaterBox_GetSurface1_2(play, &play->colCtx, this->picto.actor.world.pos.x, this->picto.actor.world.pos.z,
-                                &this->picto.actor.home.pos.y, &waterBox) ||
+    if (!BgCheck_GetWaterSurfaceNoBgId(play, &play->colCtx, this->picto.actor.world.pos.x,
+                                       this->picto.actor.world.pos.z, &this->picto.actor.home.pos.y, &waterBox) ||
         (this->picto.actor.home.pos.y <= this->picto.actor.floorHeight)) {
         return false;
     } else {
diff --git a/src/overlays/actors/ovl_En_Bigpamet/z_en_bigpamet.c b/src/overlays/actors/ovl_En_Bigpamet/z_en_bigpamet.c
index ae207cf20..bfab700db 100644
--- a/src/overlays/actors/ovl_En_Bigpamet/z_en_bigpamet.c
+++ b/src/overlays/actors/ovl_En_Bigpamet/z_en_bigpamet.c
@@ -372,12 +372,12 @@ void func_80A281B4(EnBigpamet* this) {
 
 void func_80A281DC(EnBigpamet* this, PlayState* play) {
     WaterBox* waterBox;
-    f32 sp28;
+    f32 waterSurface;
 
     if (this->actor.parent->params == GEKKO_GET_SNAPPER) {
-        if (WaterBox_GetSurface1(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z, &sp28,
-                                 &waterBox)) {
-            this->actor.depthInWater = sp28 - this->actor.world.pos.y;
+        if (BgCheck_GetWaterSurfaceNoBgIdAlt(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z,
+                                             &waterSurface, &waterBox)) {
+            this->actor.depthInWater = waterSurface - this->actor.world.pos.y;
         } else {
             this->actor.depthInWater = this->actor.world.pos.y;
         }
diff --git a/src/overlays/actors/ovl_En_Bom_Chu/z_en_bom_chu.c b/src/overlays/actors/ovl_En_Bom_Chu/z_en_bom_chu.c
index 0030bc0a5..3c1fe7a85 100644
--- a/src/overlays/actors/ovl_En_Bom_Chu/z_en_bom_chu.c
+++ b/src/overlays/actors/ovl_En_Bom_Chu/z_en_bom_chu.c
@@ -516,8 +516,8 @@ void EnBomChu_Update(Actor* thisx, PlayState* play) {
 
         waterY = this->actor.world.pos.y;
 
-        if (WaterBox_GetSurface1(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z, &waterY,
-                                 &waterBox)) {
+        if (BgCheck_GetWaterSurfaceNoBgIdAlt(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z,
+                                             &waterY, &waterBox)) {
             this->actor.depthInWater = waterY - this->actor.world.pos.y;
 
             if (this->actor.depthInWater < 0.0f) {
diff --git a/src/overlays/actors/ovl_En_Boom/z_en_boom.c b/src/overlays/actors/ovl_En_Boom/z_en_boom.c
index 5fd8c3b36..e3803f748 100644
--- a/src/overlays/actors/ovl_En_Boom/z_en_boom.c
+++ b/src/overlays/actors/ovl_En_Boom/z_en_boom.c
@@ -63,7 +63,8 @@ void func_808A24DC(EnBoom* this, PlayState* play) {
     f32 sp50 = this->actor.world.pos.y;
     u16 sp4E = this->actor.bgCheckFlags & BGCHECKFLAG_WATER;
 
-    if (WaterBox_GetSurface1(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z, &sp50, &waterBox) &&
+    if (BgCheck_GetWaterSurfaceNoBgIdAlt(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z, &sp50,
+                                         &waterBox) &&
         (this->actor.world.pos.y < sp50)) {
         Vec3f sp40;
 
diff --git a/src/overlays/actors/ovl_En_Box/z_en_box.c b/src/overlays/actors/ovl_En_Box/z_en_box.c
index 0d8784cb4..2e376073b 100644
--- a/src/overlays/actors/ovl_En_Box/z_en_box.c
+++ b/src/overlays/actors/ovl_En_Box/z_en_box.c
@@ -564,7 +564,7 @@ void EnBox_Open(EnBox* this, PlayState* play) {
                 this->unk_1A8 = 1.0f;
             }
         }
-        if (WaterBox_GetSurfaceImpl(play, &play->colCtx, this->dyna.actor.world.pos.x, this->dyna.actor.world.pos.z,
+        if (BgCheck_GetWaterSurface(play, &play->colCtx, this->dyna.actor.world.pos.x, this->dyna.actor.world.pos.z,
                                     &waterSurface, &waterBox, &bgId) &&
             (this->dyna.actor.floorHeight < waterSurface)) {
             EffectSsBubble_Spawn(play, &this->dyna.actor.world.pos, 5.0f, 2.0f, 20.0f, 0.3f);
diff --git a/src/overlays/actors/ovl_En_Clear_Tag/z_en_clear_tag.c b/src/overlays/actors/ovl_En_Clear_Tag/z_en_clear_tag.c
index bee6ead5a..c12bedb03 100644
--- a/src/overlays/actors/ovl_En_Clear_Tag/z_en_clear_tag.c
+++ b/src/overlays/actors/ovl_En_Clear_Tag/z_en_clear_tag.c
@@ -999,8 +999,8 @@ void EnClearTag_DrawEffects(Actor* thisx, PlayState* play) {
                  * `ySurface` returns the water box's surface, while `outWaterBox` returns a pointer to the WaterBox
                  */
                 ySurface = effect->pos.y;
-                if (WaterBox_GetSurface1(play, &play->colCtx, effect->pos.x + vec.x, effect->pos.z + vec.z, &ySurface,
-                                         &waterBox)) {
+                if (BgCheck_GetWaterSurfaceNoBgIdAlt(play, &play->colCtx, effect->pos.x + vec.x, effect->pos.z + vec.z,
+                                                     &ySurface, &waterBox)) {
                     if ((effect->pos.y - ySurface) < 200.0f) {
                         // Draw the splash effect.
                         Matrix_Translate(effect->pos.x + vec.x, ySurface, effect->pos.z + vec.z, MTXMODE_NEW);
diff --git a/src/overlays/actors/ovl_En_Dg/z_en_dg.c b/src/overlays/actors/ovl_En_Dg/z_en_dg.c
index 1679d8eaa..4a23870b7 100644
--- a/src/overlays/actors/ovl_En_Dg/z_en_dg.c
+++ b/src/overlays/actors/ovl_En_Dg/z_en_dg.c
@@ -1168,7 +1168,7 @@ void EnDg_Swim(EnDg* this, PlayState* play) {
     // this code will make the dog "skip" along the water's surface, assuming the floor
     // height is low enough to make it try to jump out.
     if (this->actor.bgCheckFlags & BGCHECKFLAG_WALL) {
-        if (!WaterBox_GetSurface1(play, &play->colCtx, pos.x, pos.z, &waterSurface, &waterBox)) {
+        if (!BgCheck_GetWaterSurfaceNoBgIdAlt(play, &play->colCtx, pos.x, pos.z, &waterSurface, &waterBox)) {
             if (floorHeight > -100.0f) {
                 this->dogFlags &= ~DOG_FLAG_SWIMMING;
                 this->actionFunc = EnDg_JumpOutOfWater;
diff --git a/src/overlays/actors/ovl_En_Fish2/z_en_fish2.c b/src/overlays/actors/ovl_En_Fish2/z_en_fish2.c
index ea99f42dc..2fc63e5ce 100644
--- a/src/overlays/actors/ovl_En_Fish2/z_en_fish2.c
+++ b/src/overlays/actors/ovl_En_Fish2/z_en_fish2.c
@@ -311,8 +311,8 @@ void func_80B289DC(EnFish2* this, PlayState* play) {
                 this->actor.velocity.y = 0.0f;
                 this->actor.gravity = 0.0f;
             }
-        } else if (WaterBox_GetSurface1(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z,
-                                        &this->unk_334, &waterBox)) {
+        } else if (BgCheck_GetWaterSurfaceNoBgIdAlt(play, &play->colCtx, this->actor.world.pos.x,
+                                                    this->actor.world.pos.z, &this->unk_334, &waterBox)) {
             if ((this->unk_334 != BGCHECK_Y_MIN) && (this->actor.world.pos.y < (this->unk_334 - this->unk_2D8))) {
                 this->actor.velocity.y = this->actor.world.rot.x * 0.001f * -0.1f;
                 if (this->actionFunc == func_80B297FC) {
@@ -390,8 +390,9 @@ void func_80B28C14(EnFish2* this, PlayState* play) {
         }
     }
 
-    if ((this->unk_334 == BGCHECK_Y_MIN) && !WaterBox_GetSurface1(play, &play->colCtx, this->actor.world.pos.x,
-                                                                  this->actor.world.pos.z, &this->unk_334, &waterbox)) {
+    if ((this->unk_334 == BGCHECK_Y_MIN) &&
+        !BgCheck_GetWaterSurfaceNoBgIdAlt(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z,
+                                          &this->unk_334, &waterbox)) {
         this->unk_334 = this->actor.world.pos.y;
     }
 
@@ -922,8 +923,8 @@ void func_80B2A498(EnFish2* this, PlayState* play) {
         (Animation_OnFrame(&this->skelAnime, 13.0f) || Animation_OnFrame(&this->skelAnime, 31.0f))) {
         WaterBox* waterBox;
 
-        if (WaterBox_GetSurface1(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z, &this->unk_334,
-                                 &waterBox)) {
+        if (BgCheck_GetWaterSurfaceNoBgIdAlt(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z,
+                                             &this->unk_334, &waterBox)) {
             Vec3f sp6C;
             s32 i;
 
@@ -1016,8 +1017,8 @@ void EnFish2_Update(Actor* thisx, PlayState* play2) {
                 this->actor.world.pos.y = this->unk_2D4 + 0.1f;
             }
 
-            if (WaterBox_GetSurface1(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z,
-                                     &this->unk_334, &sp6C)) {
+            if (BgCheck_GetWaterSurfaceNoBgIdAlt(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z,
+                                                 &this->unk_334, &sp6C)) {
                 if ((this->unk_334 != BGCHECK_Y_MIN) && (this->unk_334 - this->unk_2D8 < this->actor.world.pos.y)) {
                     this->actor.world.pos.y = this->unk_334 - this->unk_2D8;
                 }
@@ -1029,8 +1030,8 @@ void EnFish2_Update(Actor* thisx, PlayState* play2) {
                 f32 phi_f20 = 0;
                 WaterBox* sp4C;
 
-                if (WaterBox_GetSurface1(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z,
-                                         &this->unk_334, &sp4C)) {
+                if (BgCheck_GetWaterSurfaceNoBgIdAlt(play, &play->colCtx, this->actor.world.pos.x,
+                                                     this->actor.world.pos.z, &this->unk_334, &sp4C)) {
                     phi_f20 = D_80B2B3A8[temp_s0_2] + (this->unk_334 - this->unk_2D8);
                     phi_f2 = D_80B2B3A8[temp_s0_2 + 1] + this->unk_2D4;
                 }
@@ -1152,7 +1153,8 @@ void func_80B2AF80(EnFish2* this, PlayState* play) {
                 ptr->unk_04.y += 1.0f + ((Rand_ZeroOne() - 0.3f) * 1.2f);
                 ptr->unk_04.z += (0.3f + (Rand_ZeroOne() * 0.5f)) - 0.55f;
                 sp8C = ptr->unk_04.y;
-                if (!WaterBox_GetSurface1(play, &play->colCtx, ptr->unk_04.x, ptr->unk_04.z, &sp8C, &waterBox)) {
+                if (!BgCheck_GetWaterSurfaceNoBgIdAlt(play, &play->colCtx, ptr->unk_04.x, ptr->unk_04.z, &sp8C,
+                                                      &waterBox)) {
                     ptr->unk_00 = 0;
                 } else if (sp8C < ptr->unk_04.y) {
                     Vec3f sp7C;
diff --git a/src/overlays/actors/ovl_En_Goroiwa/z_en_goroiwa.c b/src/overlays/actors/ovl_En_Goroiwa/z_en_goroiwa.c
index a3cddbd2b..b208fcc35 100644
--- a/src/overlays/actors/ovl_En_Goroiwa/z_en_goroiwa.c
+++ b/src/overlays/actors/ovl_En_Goroiwa/z_en_goroiwa.c
@@ -500,18 +500,18 @@ s32 func_8093F6F8(EnGoroiwa* this, PlayState* play) {
 
     if (this->unk_1CA == 0) {
         WaterBox* waterBox;
-        f32 sp40;
+        f32 waterSurface;
 
-        if (WaterBox_GetSurface1_2(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z, &sp40,
-                                   &waterBox)) {
-            if ((this->actor.world.pos.y + this->unk_1DC) <= sp40) {
+        if (BgCheck_GetWaterSurfaceNoBgId(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z,
+                                          &waterSurface, &waterBox)) {
+            if ((this->actor.world.pos.y + this->unk_1DC) <= waterSurface) {
                 this->unk_1E5 |= 0x20;
-                if (sp40 < (this->unk_1DC + sp78)) {
+                if (waterSurface < (this->unk_1DC + sp78)) {
                     if (this->actor.flags & ACTOR_FLAG_INSIDE_CULLING_VOLUME) {
                         Vec3f sp34;
 
                         sp34.x = this->actor.world.pos.x;
-                        sp34.y = sp40;
+                        sp34.y = waterSurface;
                         sp34.z = this->actor.world.pos.z;
                         func_8093F198(play, &sp34, this->actor.scale.x);
                     }
diff --git a/src/overlays/actors/ovl_En_Grasshopper/z_en_grasshopper.c b/src/overlays/actors/ovl_En_Grasshopper/z_en_grasshopper.c
index c2840cc08..b105b283f 100644
--- a/src/overlays/actors/ovl_En_Grasshopper/z_en_grasshopper.c
+++ b/src/overlays/actors/ovl_En_Grasshopper/z_en_grasshopper.c
@@ -650,8 +650,8 @@ void EnGrasshopper_ApproachPlayer(EnGrasshopper* this, PlayState* play) {
     Math_ApproachF(&this->actor.world.pos.z, this->targetApproachPos.z, 0.3f, this->approachSpeed);
     Math_ApproachF(&this->approachSpeed, 7.0f, 0.3f, 1.0f);
 
-    if (WaterBox_GetSurface1(play, &play->colCtx, this->tailTipPos.x, this->tailTipPos.z, &this->waterSurface,
-                             &waterBox)) {
+    if (BgCheck_GetWaterSurfaceNoBgIdAlt(play, &play->colCtx, this->tailTipPos.x, this->tailTipPos.z,
+                                         &this->waterSurface, &waterBox)) {
         if (this->tailTipPos.y < this->waterSurface) {
             if ((this->splashCount < 3) || !(play->gameplayFrames % 8)) {
                 this->splashCount++;
@@ -700,8 +700,8 @@ void EnGrasshopper_Attack(EnGrasshopper* this, PlayState* play) {
         EnGrasshopper_InitializeEffect(this, &this->tailTipPos);
     }
 
-    if (WaterBox_GetSurface1(play, &play->colCtx, this->tailTipPos.x, this->tailTipPos.z, &this->waterSurface,
-                             &waterBox)) {
+    if (BgCheck_GetWaterSurfaceNoBgIdAlt(play, &play->colCtx, this->tailTipPos.x, this->tailTipPos.z,
+                                         &this->waterSurface, &waterBox)) {
         if (this->tailTipPos.y < this->waterSurface) {
             if ((this->splashCount < 3) || !(play->gameplayFrames % 8)) {
                 this->splashCount++;
@@ -861,8 +861,8 @@ void EnGrasshopper_Fall(EnGrasshopper* this, PlayState* play) {
         return;
     }
 
-    if (WaterBox_GetSurface1(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z, &waterSurface,
-                             &waterBox)) {
+    if (BgCheck_GetWaterSurfaceNoBgIdAlt(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z,
+                                         &waterSurface, &waterBox)) {
         if (this->actor.world.pos.y < waterSurface) {
             Vec3f splashPos;
             s32 i;
@@ -902,8 +902,8 @@ void EnGrasshopper_Fall(EnGrasshopper* this, PlayState* play) {
             firePos.x += Rand_CenteredFloat(30.0f);
             if (!isUnderWater) {
                 firePos.y = this->actor.floorHeight;
-            } else if (WaterBox_GetSurface1(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z,
-                                            &waterSurface, &waterBox)) {
+            } else if (BgCheck_GetWaterSurfaceNoBgIdAlt(play, &play->colCtx, this->actor.world.pos.x,
+                                                        this->actor.world.pos.z, &waterSurface, &waterBox)) {
                 firePos.y = waterSurface;
             }
 
diff --git a/src/overlays/actors/ovl_En_Hidden_Nuts/z_en_hidden_nuts.c b/src/overlays/actors/ovl_En_Hidden_Nuts/z_en_hidden_nuts.c
index 28c02d66f..3a0d8a2c6 100644
--- a/src/overlays/actors/ovl_En_Hidden_Nuts/z_en_hidden_nuts.c
+++ b/src/overlays/actors/ovl_En_Hidden_Nuts/z_en_hidden_nuts.c
@@ -354,15 +354,16 @@ void func_80BDBB48(EnHiddenNuts* this, PlayState* play) {
     s32 pad[3];
     f32 curFrame = this->skelAnime.curFrame;
     WaterBox* waterBox;
-    f32 sp50;
+    f32 waterSurface;
     s16 sp4E = false;
     Vec3f sp40;
 
-    if (WaterBox_GetSurface1(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z, &sp50, &waterBox) &&
-        (this->actor.world.pos.y < sp50)) {
+    if (BgCheck_GetWaterSurfaceNoBgIdAlt(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z,
+                                         &waterSurface, &waterBox) &&
+        (this->actor.world.pos.y < waterSurface)) {
         this->actor.velocity.y = 0.0f;
         Math_Vec3f_Copy(&sp40, &this->actor.world.pos);
-        sp40.y = sp50;
+        sp40.y = waterSurface;
         this->actor.gravity = 0.0f;
 
         if ((play->gameplayFrames % 8) == 0) {
diff --git a/src/overlays/actors/ovl_En_Horse/z_en_horse.c b/src/overlays/actors/ovl_En_Horse/z_en_horse.c
index b5ff9a88e..7591c1eab 100644
--- a/src/overlays/actors/ovl_En_Horse/z_en_horse.c
+++ b/src/overlays/actors/ovl_En_Horse/z_en_horse.c
@@ -3484,7 +3484,7 @@ s32 EnHorse_CalcFloorHeight(EnHorse* this, PlayState* play, Vec3f* pos, Collisio
         return 1; // No floor
     }
 
-    if ((WaterBox_GetSurface1_2(play, &play->colCtx, pos->x, pos->z, &waterY, &waterbox) == 1) &&
+    if ((BgCheck_GetWaterSurfaceNoBgId(play, &play->colCtx, pos->x, pos->z, &waterY, &waterbox) == true) &&
         (*floorHeight < waterY)) {
         return 2; // Water
     }
@@ -3563,8 +3563,8 @@ void EnHorse_CheckFloors(EnHorse* this, PlayState* play) {
     WaterBox* waterbox;
     f32 dist;
 
-    if ((WaterBox_GetSurface1_2(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z, &waterHeight,
-                                &waterbox) == true) &&
+    if ((BgCheck_GetWaterSurfaceNoBgId(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z,
+                                       &waterHeight, &waterbox) == true) &&
         (this->actor.floorHeight < waterHeight)) {
         EnHorse_ObstructMovement(this, play, 1, galloping);
         return;
diff --git a/src/overlays/actors/ovl_En_Ishi/z_en_ishi.c b/src/overlays/actors/ovl_En_Ishi/z_en_ishi.c
index 483ae5d60..3735a10a7 100644
--- a/src/overlays/actors/ovl_En_Ishi/z_en_ishi.c
+++ b/src/overlays/actors/ovl_En_Ishi/z_en_ishi.c
@@ -395,7 +395,7 @@ s32 EnIshi_IsUnderwater(EnIshi* this, PlayState* play) {
     f32 waterSurface;
     s32 bgId;
 
-    if (WaterBox_GetSurfaceImpl(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z, &waterSurface,
+    if (BgCheck_GetWaterSurface(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z, &waterSurface,
                                 &waterBox, &bgId) &&
         (this->actor.world.pos.y < waterSurface)) {
         return true;
diff --git a/src/overlays/actors/ovl_En_Kusa/z_en_kusa.c b/src/overlays/actors/ovl_En_Kusa/z_en_kusa.c
index 003fbc751..00a7a8334 100644
--- a/src/overlays/actors/ovl_En_Kusa/z_en_kusa.c
+++ b/src/overlays/actors/ovl_En_Kusa/z_en_kusa.c
@@ -341,7 +341,7 @@ s32 EnKusa_IsUnderwater(EnKusa* this, PlayState* play) {
     f32 waterSurface;
     s32 bgId;
 
-    if (WaterBox_GetSurfaceImpl(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z, &waterSurface,
+    if (BgCheck_GetWaterSurface(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z, &waterSurface,
                                 &waterBox, &bgId) &&
         (this->actor.world.pos.y < waterSurface)) {
         return true;
diff --git a/src/overlays/actors/ovl_En_Mushi2/z_en_mushi2.c b/src/overlays/actors/ovl_En_Mushi2/z_en_mushi2.c
index 8e59bfb55..5464c5bea 100644
--- a/src/overlays/actors/ovl_En_Mushi2/z_en_mushi2.c
+++ b/src/overlays/actors/ovl_En_Mushi2/z_en_mushi2.c
@@ -127,14 +127,14 @@ s32 func_80A68860(EnMushi2* this, PlayState* play) {
     CollisionPoly* sp3C;
     f32 temp_f0 = BgCheck_EntityRaycastFloor5(&play->colCtx, &sp3C, &bgId, &this->actor, &this->actor.world.pos);
     WaterBox* waterBox;
-    f32 sp30;
+    f32 waterSurface;
 
     if ((temp_f0 > (BGCHECK_Y_MIN + 1)) && ((this->actor.world.pos.y - 150.0f) < temp_f0)) {
         return true;
     }
 
-    return WaterBox_GetSurface1_2(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z, &sp30,
-                                  &waterBox);
+    return BgCheck_GetWaterSurfaceNoBgId(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z,
+                                         &waterSurface, &waterBox);
 }
 
 s32 func_80A68910(EnMushi2* this, PlayState* play) {
@@ -528,16 +528,16 @@ void func_80A697C4(EnMushi2* this, PlayState* play) {
 
     if (!(this->unk_30C & (0x10 | 0x4))) {
         WaterBox* waterBox;
-        f32 sp2C;
+        f32 waterSurface;
 
         this->unk_30C &= ~(0x40 | 0x8 | 0x2);
         if (!func_80A69468(this, play) && !func_80A6958C(this, play)) {
             func_80A6969C(this, play);
         }
 
-        if (WaterBox_GetSurface1_2(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z, &sp2C,
-                                   &waterBox)) {
-            this->actor.depthInWater = sp2C - this->actor.world.pos.y;
+        if (BgCheck_GetWaterSurfaceNoBgId(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z,
+                                          &waterSurface, &waterBox)) {
+            this->actor.depthInWater = waterSurface - this->actor.world.pos.y;
             if (this->actor.depthInWater >= 1.0f) {
                 this->unk_30C |= 0x20;
             } else {
@@ -577,14 +577,14 @@ void func_80A697C4(EnMushi2* this, PlayState* play) {
 s32 func_80A699E4(EnMushi2* this, PlayState* play) {
     s32 pad;
     WaterBox* waterBox;
-    f32 sp3C;
+    f32 waterSurface;
 
     if (this->unk_328.y < 0.0f) {
         f32 x = (2.0f * this->unk_328.x) + this->actor.world.pos.x;
         f32 y = (2.0f * this->unk_328.y) + this->actor.world.pos.y;
         f32 z = (2.0f * this->unk_328.z) + this->actor.world.pos.z;
 
-        if (WaterBox_GetSurface1_2(play, &play->colCtx, x, z, &sp3C, &waterBox) && (y <= sp3C)) {
+        if (BgCheck_GetWaterSurfaceNoBgId(play, &play->colCtx, x, z, &waterSurface, &waterBox) && (y <= waterSurface)) {
             return true;
         }
     }
@@ -680,7 +680,7 @@ s32 EnMushi2_IsUnderwater(EnMushi2* this, PlayState* play) {
     f32 waterSurface;
     s32 bgId;
 
-    if (WaterBox_GetSurfaceImpl(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z, &waterSurface,
+    if (BgCheck_GetWaterSurface(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z, &waterSurface,
                                 &waterBox, &bgId) &&
         (this->actor.world.pos.y < waterSurface)) {
         return true;
diff --git a/src/overlays/actors/ovl_En_Okuta/z_en_okuta.c b/src/overlays/actors/ovl_En_Okuta/z_en_okuta.c
index 8c5744f6c..b0fe9cf41 100644
--- a/src/overlays/actors/ovl_En_Okuta/z_en_okuta.c
+++ b/src/overlays/actors/ovl_En_Okuta/z_en_okuta.c
@@ -166,8 +166,8 @@ void EnOkuta_Init(Actor* thisx, PlayState* play2) {
         thisx->floorHeight =
             BgCheck_EntityRaycastFloor5(&play->colCtx, &thisx->floorPoly, &bgId, thisx, &thisx->world.pos);
 
-        if (!WaterBox_GetSurface1_2(play, &play->colCtx, thisx->world.pos.x, thisx->world.pos.z, &waterSurface,
-                                    &waterBox) ||
+        if (!BgCheck_GetWaterSurfaceNoBgId(play, &play->colCtx, thisx->world.pos.x, thisx->world.pos.z, &waterSurface,
+                                           &waterBox) ||
             waterSurface <= thisx->floorHeight) {
             Actor_Kill(thisx);
         } else {
diff --git a/src/overlays/actors/ovl_En_Pp/z_en_pp.c b/src/overlays/actors/ovl_En_Pp/z_en_pp.c
index f71bb2921..aa40aba7e 100644
--- a/src/overlays/actors/ovl_En_Pp/z_en_pp.c
+++ b/src/overlays/actors/ovl_En_Pp/z_en_pp.c
@@ -1050,8 +1050,8 @@ void EnPp_Dead(EnPp* this, PlayState* play) {
 
     isUnderWater = false;
     if ((this->action == EN_PP_ACTION_DEAD) &&
-        (WaterBox_GetSurface1(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z, &waterSurface,
-                              &waterBox))) {
+        (BgCheck_GetWaterSurfaceNoBgIdAlt(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z,
+                                          &waterSurface, &waterBox))) {
         if (this->actor.world.pos.y < waterSurface) {
             for (i = 0; i < 5; i++) {
                 Math_Vec3f_Copy(&splashPos, &this->actor.world.pos);
@@ -1218,8 +1218,8 @@ void EnPp_Fragment_Move(EnPp* this, PlayState* play) {
         this->actor.shape.rot.z += this->fragmentAngularVelocity.z;
     }
 
-    if (WaterBox_GetSurface1(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z, &waterSurface,
-                             &waterBox) &&
+    if (BgCheck_GetWaterSurfaceNoBgIdAlt(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z,
+                                         &waterSurface, &waterBox) &&
         (this->actor.world.pos.y < (waterSurface + 5.0f))) {
         this->timer = 0;
         if (EN_PP_GET_TYPE(&this->actor) == EN_PP_TYPE_FRAGMENT_BODY) {
@@ -1418,8 +1418,8 @@ void EnPp_Update(Actor* thisx, PlayState* play) {
     }
 
     if ((this->action < EN_PP_ACTION_DEAD) &&
-        (WaterBox_GetSurface1(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z, &waterSurface,
-                              &waterBox)) &&
+        (BgCheck_GetWaterSurfaceNoBgIdAlt(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z,
+                                          &waterSurface, &waterBox)) &&
         (this->actor.world.pos.y < waterSurface)) {
         EnPp_SetupDead(this, play);
         return;
diff --git a/src/overlays/actors/ovl_En_Pr/z_en_pr.c b/src/overlays/actors/ovl_En_Pr/z_en_pr.c
index 2bfb008f6..c3003b850 100644
--- a/src/overlays/actors/ovl_En_Pr/z_en_pr.c
+++ b/src/overlays/actors/ovl_En_Pr/z_en_pr.c
@@ -221,8 +221,8 @@ s32 func_80A324E0(EnPr* this, PlayState* play) {
         return 1;
     }
 
-    if (WaterBox_GetSurface1(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z, &this->unk_2B4,
-                             &waterBox)) {
+    if (BgCheck_GetWaterSurfaceNoBgIdAlt(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z,
+                                         &this->unk_2B4, &waterBox)) {
         if ((this->unk_2B4 - 30.0f) < this->actor.world.pos.y) {
             this->unk_2B8 = this->unk_2B4 - 30.0f;
             return 2;
@@ -341,8 +341,8 @@ void func_80A32A40(EnPr* this, PlayState* play) {
     Math_Vec3f_Copy(&sp34, &this->actor.world.pos);
     sp34.y = Rand_CenteredFloat(50.0f) + this->actor.home.pos.y;
 
-    if (WaterBox_GetSurface1(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z, &this->unk_2B4,
-                             &waterBox)) {
+    if (BgCheck_GetWaterSurfaceNoBgIdAlt(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z,
+                                         &this->unk_2B4, &waterBox)) {
         if (sp34.y < (this->unk_2B4 - 30.0f)) {
             this->unk_2B8 = sp34.y;
         } else {
@@ -448,8 +448,8 @@ void func_80A32F48(EnPr* this, PlayState* play) {
         this->unk_208 = 0;
     }
 
-    if (WaterBox_GetSurface1(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z, &this->unk_2B4,
-                             &waterBox)) {
+    if (BgCheck_GetWaterSurfaceNoBgIdAlt(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z,
+                                         &this->unk_2B4, &waterBox)) {
         if ((this->unk_2B4 - 100.0f) < this->actor.world.pos.y) {
             this->unk_212 += 0xBB8;
             this->unk_2C4 = 2.0f * Math_SinS(this->unk_212);
diff --git a/src/overlays/actors/ovl_En_Pr2/z_en_pr2.c b/src/overlays/actors/ovl_En_Pr2/z_en_pr2.c
index 57bb0a65b..d71646bba 100644
--- a/src/overlays/actors/ovl_En_Pr2/z_en_pr2.c
+++ b/src/overlays/actors/ovl_En_Pr2/z_en_pr2.c
@@ -522,8 +522,8 @@ void EnPr2_Attack(EnPr2* this, PlayState* play) {
             Math_Vec3f_Copy(&this->newHome, &this->actor.world.pos);
         }
 
-        if (WaterBox_GetSurface1(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z,
-                                 &this->waterSurfaceHeight, &waterBox)) {
+        if (BgCheck_GetWaterSurfaceNoBgIdAlt(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z,
+                                             &this->waterSurfaceHeight, &waterBox)) {
             if (this->waypointPos.y > (this->waterSurfaceHeight - 40.0f)) {
                 this->waypointPos.y = this->waterSurfaceHeight - 40.0f;
             }
@@ -609,8 +609,8 @@ void EnPr2_Die(EnPr2* this, PlayState* play) {
             this->bubbleToggle = true;
         }
 
-        if (WaterBox_GetSurface1(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z,
-                                 &this->waterSurfaceHeight, &waterBox)) {
+        if (BgCheck_GetWaterSurfaceNoBgIdAlt(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z,
+                                             &this->waterSurfaceHeight, &waterBox)) {
             if (this->actor.world.pos.y >= (this->waterSurfaceHeight - 15.0f)) {
                 nearSurface = true;
             } else {
diff --git a/src/overlays/actors/ovl_En_Prz/z_en_prz.c b/src/overlays/actors/ovl_En_Prz/z_en_prz.c
index 83d882dd4..b11346a61 100644
--- a/src/overlays/actors/ovl_En_Prz/z_en_prz.c
+++ b/src/overlays/actors/ovl_En_Prz/z_en_prz.c
@@ -158,8 +158,8 @@ s32 func_80A75FA4(EnPrz* this, PlayState* play) {
     WaterBox* waterBox;
     f32 temp_f0;
 
-    if (WaterBox_GetSurface1(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z, &this->unk_210,
-                             &waterBox)) {
+    if (BgCheck_GetWaterSurfaceNoBgIdAlt(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z,
+                                         &this->unk_210, &waterBox)) {
         temp_f0 = BREG(10) + (this->unk_210 - 10.0f);
         if (temp_f0 < this->actor.world.pos.y) {
             this->unk_1D8.y = temp_f0;
@@ -407,8 +407,8 @@ void func_80A76B14(EnPrz* this, PlayState* play) {
     Math_SmoothStepToS(&this->actor.shape.rot.z, this->unk_1FC, 5, 0x2710, 0x3E8);
     Math_SmoothStepToS(&this->actor.shape.rot.y, this->unk_1FE, 5, 0x2710, 0x3E8);
 
-    if (WaterBox_GetSurface1(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z, &this->unk_210,
-                             &waterBox)) {
+    if (BgCheck_GetWaterSurfaceNoBgIdAlt(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z,
+                                         &this->unk_210, &waterBox)) {
         if ((this->unk_210 - 15.0f) <= this->actor.world.pos.y) {
             phi_s0 = true;
         } else {
diff --git a/src/overlays/actors/ovl_En_Raf/z_en_raf.c b/src/overlays/actors/ovl_En_Raf/z_en_raf.c
index e0e11bf69..f66468c0e 100644
--- a/src/overlays/actors/ovl_En_Raf/z_en_raf.c
+++ b/src/overlays/actors/ovl_En_Raf/z_en_raf.c
@@ -739,8 +739,8 @@ void EnRaf_Update(Actor* thisx, PlayState* play) {
 
     if (this->mainType != CARNIVOROUS_LILY_TYPE_NO_WATER_INTERACTIONS) {
         ySurface = BREG(60) + (this->dyna.actor.world.pos.y - 60.0f);
-        if (WaterBox_GetSurface1(play, &play->colCtx, this->dyna.actor.world.pos.x, this->dyna.actor.world.pos.z,
-                                 &ySurface, &waterBox)) {
+        if (BgCheck_GetWaterSurfaceNoBgIdAlt(play, &play->colCtx, this->dyna.actor.world.pos.x,
+                                             this->dyna.actor.world.pos.z, &ySurface, &waterBox)) {
             ySurface -= this->bobOffset + BREG(59);
             Math_ApproachF(&this->dyna.actor.world.pos.y, this->heightDiffFromPlayer + ySurface, 0.5f, 40.0f);
             if (this->rippleTimer == 0) {
diff --git a/src/overlays/actors/ovl_En_Rat/z_en_rat.c b/src/overlays/actors/ovl_En_Rat/z_en_rat.c
index 12f91d131..4c6bbd842 100644
--- a/src/overlays/actors/ovl_En_Rat/z_en_rat.c
+++ b/src/overlays/actors/ovl_En_Rat/z_en_rat.c
@@ -356,7 +356,7 @@ s32 EnRat_IsOnCollisionPoly(PlayState* play, Vec3f* posA, Vec3f* posB, Vec3f* po
     s32 isOnWater;
     f32 waterSurface;
 
-    if (WaterBox_GetSurface1(play, &play->colCtx, posB->x, posB->z, &waterSurface, &waterBox) &&
+    if (BgCheck_GetWaterSurfaceNoBgIdAlt(play, &play->colCtx, posB->x, posB->z, &waterSurface, &waterBox) &&
         (waterSurface <= posA->y) && (posB->y <= waterSurface)) {
         isOnWater = true;
     } else {
diff --git a/src/overlays/actors/ovl_En_Syateki_Okuta/z_en_syateki_okuta.c b/src/overlays/actors/ovl_En_Syateki_Okuta/z_en_syateki_okuta.c
index 41032de1f..8b64c2f97 100644
--- a/src/overlays/actors/ovl_En_Syateki_Okuta/z_en_syateki_okuta.c
+++ b/src/overlays/actors/ovl_En_Syateki_Okuta/z_en_syateki_okuta.c
@@ -100,8 +100,8 @@ void EnSyatekiOkuta_Init(Actor* thisx, PlayState* play) {
     this->actor.floorHeight =
         BgCheck_EntityRaycastFloor5(&play->colCtx, &this->actor.floorPoly, &bgId, &this->actor, &this->actor.world.pos);
 
-    if (!WaterBox_GetSurface1_2(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z, &ySurface,
-                                &waterbox) ||
+    if (!BgCheck_GetWaterSurfaceNoBgId(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z, &ySurface,
+                                       &waterbox) ||
         (ySurface <= this->actor.floorHeight)) {
         Actor_Kill(&this->actor);
     } else {
diff --git a/src/overlays/actors/ovl_En_Tanron1/z_en_tanron1.c b/src/overlays/actors/ovl_En_Tanron1/z_en_tanron1.c
index 79941fe4b..301a11d73 100644
--- a/src/overlays/actors/ovl_En_Tanron1/z_en_tanron1.c
+++ b/src/overlays/actors/ovl_En_Tanron1/z_en_tanron1.c
@@ -343,7 +343,8 @@ void func_80BB5318(EnTanron1* this, PlayState* play) {
                             }
                             ptr->unk_3C = BgCheck_EntityRaycastFloor1(&play->colCtx, &sp98, &ptr->unk_00);
                             sp9C = ptr->unk_00.y;
-                            WaterBox_GetSurface1(play, &play->colCtx, ptr->unk_00.x, ptr->unk_00.z, &sp9C, &waterBox);
+                            BgCheck_GetWaterSurfaceNoBgIdAlt(play, &play->colCtx, ptr->unk_00.x, ptr->unk_00.z, &sp9C,
+                                                             &waterBox);
                             if ((sp9C < ptr->unk_00.y) && (ptr->unk_3C < sp9C)) {
                                 ptr->unk_3C = sp9C;
                             }
diff --git a/src/overlays/actors/ovl_En_Test5/z_en_test5.c b/src/overlays/actors/ovl_En_Test5/z_en_test5.c
index cdc9c2e19..70eaf23b7 100644
--- a/src/overlays/actors/ovl_En_Test5/z_en_test5.c
+++ b/src/overlays/actors/ovl_En_Test5/z_en_test5.c
@@ -37,8 +37,8 @@ void EnTest5_Init(Actor* thisx, PlayState* play2) {
     f32 ySurface;
 
     // If not spawned above a water source, immediately despawn
-    if (!WaterBox_GetSurface1(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z, &ySurface,
-                              &waterBox)) {
+    if (!BgCheck_GetWaterSurfaceNoBgIdAlt(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z,
+                                          &ySurface, &waterBox)) {
         Actor_Kill(&this->actor);
         return;
     }
diff --git a/src/overlays/actors/ovl_En_Zog/z_en_zog.c b/src/overlays/actors/ovl_En_Zog/z_en_zog.c
index 5a66eb475..af25ebfdc 100644
--- a/src/overlays/actors/ovl_En_Zog/z_en_zog.c
+++ b/src/overlays/actors/ovl_En_Zog/z_en_zog.c
@@ -897,7 +897,7 @@ void func_80B94E34(EnZog* this, PlayState* play) {
             sp38.x += Rand_CenteredFloat(30.0f);
             sp38.y += 20.0f;
             sp38.z += Rand_CenteredFloat(30.0f);
-            if (WaterBox_GetSurface1(play, &play->colCtx, sp38.x, sp38.z, &sp38.y, &waterBox) &&
+            if (BgCheck_GetWaterSurfaceNoBgIdAlt(play, &play->colCtx, sp38.x, sp38.z, &sp38.y, &waterBox) &&
                 (this->actor.world.pos.y < sp38.y)) {
                 EffectSsGSplash_Spawn(play, &sp38, NULL, NULL, 1,
                                       Rand_ZeroFloat(this->actor.speed * 40.0f) + (this->actor.speed * 60.0f));
diff --git a/src/overlays/actors/ovl_En_Zoraegg/z_en_zoraegg.c b/src/overlays/actors/ovl_En_Zoraegg/z_en_zoraegg.c
index 3220b4823..c28d51bd4 100644
--- a/src/overlays/actors/ovl_En_Zoraegg/z_en_zoraegg.c
+++ b/src/overlays/actors/ovl_En_Zoraegg/z_en_zoraegg.c
@@ -598,7 +598,8 @@ void func_80B32C34(EnZoraegg* this, PlayState* play) {
     this->actor.focus.pos.y += 10.0f;
     sp30 = this->actor.world.pos.y;
 
-    if (WaterBox_GetSurface1(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z, &sp30, &waterBox)) {
+    if (BgCheck_GetWaterSurfaceNoBgIdAlt(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z, &sp30,
+                                         &waterBox)) {
         if ((this->actor.world.pos.y + 50.0f) < sp30) {
             this->actionFunc = func_80B32BB8;
         }
@@ -619,7 +620,8 @@ void func_80B32D08(EnZoraegg* this, PlayState* play) {
     this->actor.focus.pos.y += 10.0f;
     sp40 = this->actor.world.pos.y;
 
-    if (WaterBox_GetSurface1(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z, &sp40, &waterBox)) {
+    if (BgCheck_GetWaterSurfaceNoBgIdAlt(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z, &sp40,
+                                         &waterBox)) {
         if (this->actor.world.pos.y < sp40) {
             sp34.x = this->actor.world.pos.x;
             sp34.y = sp40;
diff --git a/src/overlays/actors/ovl_Obj_Aqua/z_obj_aqua.c b/src/overlays/actors/ovl_Obj_Aqua/z_obj_aqua.c
index 7deb602c8..158921a47 100644
--- a/src/overlays/actors/ovl_Obj_Aqua/z_obj_aqua.c
+++ b/src/overlays/actors/ovl_Obj_Aqua/z_obj_aqua.c
@@ -133,7 +133,7 @@ s32 ObjAqua_IsUnderwater(ObjAqua* this, PlayState* play) {
     f32 waterSurface;
     s32 bgId;
 
-    if (WaterBox_GetSurfaceImpl(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z, &waterSurface,
+    if (BgCheck_GetWaterSurface(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z, &waterSurface,
                                 &waterBox, &bgId) &&
         (this->actor.world.pos.y < waterSurface)) {
         return true;
diff --git a/src/overlays/actors/ovl_Obj_Bombiwa/z_obj_bombiwa.c b/src/overlays/actors/ovl_Obj_Bombiwa/z_obj_bombiwa.c
index fc63831c0..fe561cc77 100644
--- a/src/overlays/actors/ovl_Obj_Bombiwa/z_obj_bombiwa.c
+++ b/src/overlays/actors/ovl_Obj_Bombiwa/z_obj_bombiwa.c
@@ -150,7 +150,7 @@ s32 ObjBombiwa_IsUnderwater(ObjBombiwa* this, PlayState* play) {
     f32 waterSurface;
     s32 bgId;
 
-    if (WaterBox_GetSurfaceImpl(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z, &waterSurface,
+    if (BgCheck_GetWaterSurface(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z, &waterSurface,
                                 &waterBox, &bgId) &&
         (this->actor.world.pos.y < waterSurface)) {
         return true;
diff --git a/src/overlays/actors/ovl_Obj_Grass_Unit/z_obj_grass_unit.c b/src/overlays/actors/ovl_Obj_Grass_Unit/z_obj_grass_unit.c
index a8d31172a..66c285eb4 100644
--- a/src/overlays/actors/ovl_Obj_Grass_Unit/z_obj_grass_unit.c
+++ b/src/overlays/actors/ovl_Obj_Grass_Unit/z_obj_grass_unit.c
@@ -92,7 +92,7 @@ s32 ObjGrassUnit_IsUnderwater(PlayState* play, Vec3f* pos) {
     f32 waterSurface;
     s32 bgId;
 
-    if (WaterBox_GetSurfaceImpl(play, &play->colCtx, pos->x, pos->z, &waterSurface, &waterBox, &bgId) &&
+    if (BgCheck_GetWaterSurface(play, &play->colCtx, pos->x, pos->z, &waterSurface, &waterBox, &bgId) &&
         (pos->y < waterSurface)) {
         return true;
     }
diff --git a/src/overlays/actors/ovl_Obj_Hamishi/z_obj_hamishi.c b/src/overlays/actors/ovl_Obj_Hamishi/z_obj_hamishi.c
index 69a4a3eea..fe64a9bcc 100644
--- a/src/overlays/actors/ovl_Obj_Hamishi/z_obj_hamishi.c
+++ b/src/overlays/actors/ovl_Obj_Hamishi/z_obj_hamishi.c
@@ -150,7 +150,7 @@ s32 ObjHamishi_IsUnderwater(ObjHamishi* this, PlayState* play) {
     f32 waterSurface;
     s32 bgId;
 
-    if (WaterBox_GetSurfaceImpl(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z, &waterSurface,
+    if (BgCheck_GetWaterSurface(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z, &waterSurface,
                                 &waterBox, &bgId) &&
         (this->actor.world.pos.y < waterSurface)) {
         return true;
diff --git a/src/overlays/actors/ovl_Obj_Iceblock/z_obj_iceblock.c b/src/overlays/actors/ovl_Obj_Iceblock/z_obj_iceblock.c
index ccf0b491e..265ec2894 100644
--- a/src/overlays/actors/ovl_Obj_Iceblock/z_obj_iceblock.c
+++ b/src/overlays/actors/ovl_Obj_Iceblock/z_obj_iceblock.c
@@ -347,7 +347,7 @@ s32 func_80A23D08(ObjIceblock* this, PlayState* play) {
             }
         }
 
-        if (WaterBox_GetSurface1_2(play, &play->colCtx, spA4.x, spA4.z, &ptr->unk_0C, &waterBox)) {
+        if (BgCheck_GetWaterSurfaceNoBgId(play, &play->colCtx, spA4.x, spA4.z, &ptr->unk_0C, &waterBox)) {
             if (phi_f20 < ptr->unk_0C) {
                 spB8 = i;
                 phi_f20 = ptr->unk_0C;
diff --git a/src/overlays/actors/ovl_Obj_Syokudai/z_obj_syokudai.c b/src/overlays/actors/ovl_Obj_Syokudai/z_obj_syokudai.c
index cac6a4bcd..6557b08ac 100644
--- a/src/overlays/actors/ovl_Obj_Syokudai/z_obj_syokudai.c
+++ b/src/overlays/actors/ovl_Obj_Syokudai/z_obj_syokudai.c
@@ -155,8 +155,8 @@ void ObjSyokudai_Update(Actor* thisx, PlayState* play2) {
             this->pendingAction = OBJ_SYOKUDAI_PENDING_ACTION_NONE;
         }
     } else {
-        if (WaterBox_GetSurface1_2(play, &play->colCtx, thisx->world.pos.x, thisx->world.pos.z, &waterSurface,
-                                   &waterBox) &&
+        if (BgCheck_GetWaterSurfaceNoBgId(play, &play->colCtx, thisx->world.pos.x, thisx->world.pos.z, &waterSurface,
+                                          &waterBox) &&
             ((waterSurface - thisx->world.pos.y) > OBJ_SYOKUDAI_FLAME_HEIGHT)) {
 
             this->snuffTimer = OBJ_SYOKUDAI_SNUFF_OUT;
diff --git a/src/overlays/actors/ovl_Obj_Wind/z_obj_wind.c b/src/overlays/actors/ovl_Obj_Wind/z_obj_wind.c
index 16b837755..bbc235383 100644
--- a/src/overlays/actors/ovl_Obj_Wind/z_obj_wind.c
+++ b/src/overlays/actors/ovl_Obj_Wind/z_obj_wind.c
@@ -39,8 +39,8 @@ void ObjWind_Init(Actor* thisx, PlayState* play) {
     f32 ySurface;
 
     Actor_ProcessInitChain(&this->actor, sInitChain);
-    if (WaterBox_GetSurface1(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z, &ySurface,
-                             &waterbox) &&
+    if (BgCheck_GetWaterSurfaceNoBgIdAlt(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z,
+                                         &ySurface, &waterbox) &&
         (this->actor.world.pos.y < ySurface)) {
         this->isUnderWater = true;
     }
diff --git a/src/overlays/actors/ovl_player_actor/z_player.c b/src/overlays/actors/ovl_player_actor/z_player.c
index 482fe7d8f..34d30a937 100644
--- a/src/overlays/actors/ovl_player_actor/z_player.c
+++ b/src/overlays/actors/ovl_player_actor/z_player.c
@@ -6977,7 +6977,7 @@ void func_80836D8C(Player* this) {
 }
 
 s32 func_80836DC0(PlayState* play, Player* this) {
-    if ((MREG(48) != 0) || func_800C9DDC(&play->colCtx, this->actor.floorPoly, this->actor.floorBgId)) {
+    if ((MREG(48) != 0) || SurfaceType_IsFloorDekuFlower(&play->colCtx, this->actor.floorPoly, this->actor.floorBgId)) {
         Player_SetAction(play, this, Player_Action_93, 0);
         this->stateFlags1 &= ~(PLAYER_STATE1_PARALLEL | PLAYER_STATE1_LOCK_ON_FORCED_TO_RELEASE);
         Player_Anim_PlayOnceMorph(play, this, &gPlayerAnim_pn_attack);
@@ -7231,7 +7231,7 @@ s32 func_80837730(PlayState* play, Player* this, f32 arg2, s32 scale) {
 
         Math_Vec3f_Copy(&pos, &this->bodyPartsPos[PLAYER_BODYPART_WAIST]);
         pos.y += 20.0f;
-        if (WaterBox_GetSurface1(play, &play->colCtx, pos.x, pos.z, &pos.y, &waterBox)) {
+        if (BgCheck_GetWaterSurfaceNoBgIdAlt(play, &play->colCtx, pos.x, pos.z, &pos.y, &waterBox)) {
             sp34 = pos.y - this->bodyPartsPos[PLAYER_BODYPART_LEFT_FOOT].y;
             if ((sp34 > -2.0f) && (sp34 < 100.0f)) {
                 EffectSsGSplash_Spawn(play, &pos, NULL, NULL,
@@ -7548,7 +7548,8 @@ void func_8083827C(Player* this, PlayState* play) {
                                 sp48 = func_80835CD8(play, this, &D_8085D154, &sp4C, &sp60, &sp5C);
                                 sp44 = this->actor.world.pos.y;
 
-                                if (WaterBox_GetSurface1(play, &play->colCtx, sp4C.x, sp4C.z, &sp44, &waterBox) &&
+                                if (BgCheck_GetWaterSurfaceNoBgIdAlt(play, &play->colCtx, sp4C.x, sp4C.z, &sp44,
+                                                                     &waterBox) &&
                                     ((sp44 - sp48) > 50.0f)) {
                                     func_80834DB8(this, &gPlayerAnim_link_normal_run_jump_water_fall, 6.0f, play);
                                     Player_SetAction(play, this, Player_Action_27, 0);
@@ -8532,8 +8533,8 @@ s32 func_8083A878(PlayState* play, Player* this, f32 arg2) {
     WaterBox* waterBox;
     f32 ySurface = this->actor.world.pos.y;
 
-    if (WaterBox_GetSurface1(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z, &ySurface,
-                             &waterBox)) {
+    if (BgCheck_GetWaterSurfaceNoBgIdAlt(play, &play->colCtx, this->actor.world.pos.x, this->actor.world.pos.z,
+                                         &ySurface, &waterBox)) {
         ySurface -= this->actor.world.pos.y;
         if (this->ageProperties->unk_24 <= ySurface) {
             Player_SetAction(play, this, Player_Action_55, 0);
@@ -11550,7 +11551,7 @@ void Player_UpdateInterface(PlayState* play, Player* this) {
                     (sp38 || ((this->stateFlags1 & PLAYER_STATE1_8000000) &&
                               !(this->actor.bgCheckFlags & BGCHECKFLAG_GROUND)))) ||
                    ((this->transformation == PLAYER_FORM_DEKU) && (this->actor.bgCheckFlags & BGCHECKFLAG_GROUND) &&
-                    func_800C9DDC(&play->colCtx, this->actor.floorPoly, this->actor.floorBgId))) {
+                    SurfaceType_IsFloorDekuFlower(&play->colCtx, this->actor.floorPoly, this->actor.floorBgId))) {
             doActionA = (this->transformation == PLAYER_FORM_ZORA) ? DO_ACTION_SWIM
                         : ((this->stateFlags1 & PLAYER_STATE1_8000000) && (interactRangeActor != NULL) &&
                            (interactRangeActor->id == ACTOR_EN_ZOG))
diff --git a/src/overlays/effects/ovl_Effect_Ss_Bubble/z_eff_ss_bubble.c b/src/overlays/effects/ovl_Effect_Ss_Bubble/z_eff_ss_bubble.c
index 8c6bfb721..fe0847c53 100644
--- a/src/overlays/effects/ovl_Effect_Ss_Bubble/z_eff_ss_bubble.c
+++ b/src/overlays/effects/ovl_Effect_Ss_Bubble/z_eff_ss_bubble.c
@@ -74,7 +74,7 @@ void EffectSsBubble_Update(PlayState* play2, u32 index, EffectSs* this) {
     Vec3f ripplePos;
     PlayState* play = play2;
 
-    if (!WaterBox_GetSurface1(play, &play->colCtx, this->pos.x, this->pos.z, &waterSurfaceY, &waterBox)) {
+    if (!BgCheck_GetWaterSurfaceNoBgIdAlt(play, &play->colCtx, this->pos.x, this->pos.z, &waterSurfaceY, &waterBox)) {
         this->life = -1;
         return;
     }
diff --git a/src/overlays/effects/ovl_Effect_Ss_G_Ripple/z_eff_ss_g_ripple.c b/src/overlays/effects/ovl_Effect_Ss_G_Ripple/z_eff_ss_g_ripple.c
index 918da4a77..54bd8d83c 100644
--- a/src/overlays/effects/ovl_Effect_Ss_G_Ripple/z_eff_ss_g_ripple.c
+++ b/src/overlays/effects/ovl_Effect_Ss_G_Ripple/z_eff_ss_g_ripple.c
@@ -57,7 +57,7 @@ u32 EffectSsGRipple_Init(PlayState* play, u32 index, EffectSs* this, void* initP
     this->rEnvColorG = 255;
     this->rEnvColorB = 255;
     this->rEnvColorA = 255;
-    this->rWaterBoxNum = WaterBox_GetSurface2(play, &play->colCtx, &initParams->pos, 3.0f, &waterBox, &bgId);
+    this->rWaterBoxNum = BgCheck_FindWaterBox(play, &play->colCtx, &initParams->pos, 3.0f, &waterBox, &bgId);
     this->rBgId = bgId;
 
     return 1;
@@ -80,7 +80,7 @@ void EffectSsGRipple_DrawRipple(PlayState* play2, EffectSs* this, TexturePtr tex
     colHeader = BgCheck_GetCollisionHeader(&play->colCtx, this->rBgId);
 
     if ((this->rWaterBoxNum != -1) && (colHeader != NULL) && (this->rWaterBoxNum < colHeader->numWaterBoxes)) {
-        yPos = func_800CA568(&play->colCtx, this->rWaterBoxNum, this->rBgId);
+        yPos = WaterBox_GetSurface(&play->colCtx, this->rWaterBoxNum, this->rBgId);
     } else {
         yPos = this->pos.y;
     }
@@ -118,7 +118,7 @@ void EffectSsGRipple_Update(PlayState* play, u32 index, EffectSs* this) {
     WaterBox* waterBox;
     s32 bgId;
 
-    this->rWaterBoxNum = WaterBox_GetSurface2(play, &play->colCtx, &this->pos, 3.0f, &waterBox, &bgId);
+    this->rWaterBoxNum = BgCheck_FindWaterBox(play, &play->colCtx, &this->pos, 3.0f, &waterBox, &bgId);
     this->rBgId = bgId;
 
     if (DECR(this->rLifespan) == 0) {