Add macros for metatile manipulation

10 files changed, 59 insertions, 57 deletions

diff --git a/src/battle_pyramid.c b/src/battle_pyramid.c
index 340c17c59..92ff257b0 100644
--- a/src/battle_pyramid.c
+++ b/src/battle_pyramid.c
@@ -1267,7 +1267,7 @@ static u8 GetPostBattleDirectionHintTextIndex(int *hintType, u8 minDistanceForEx
     {
         for (x = 0; x < 32; x++)
         {
-            if ((map[x] & 0x3FF) == FLOOR_EXIT_METATILE)
+            if ((map[x] & MAP_METATILE_ID_MASK) == FLOOR_EXIT_METATILE)
             {
                 x += 7 - gEventObjects[gSelectedEventObject].initialCoords.x;
                 y += 7 - gEventObjects[gSelectedEventObject].initialCoords.y;
@@ -1568,7 +1568,7 @@ void GenerateBattlePyramidFloorLayout(u16 *backupMapData, bool8 setPlayerPositio
         {
             for (x = 0; x < mapLayout->width; x++)
             {
-                if ((layoutMap[x] & 0x3FF) != FLOOR_EXIT_METATILE)
+                if ((layoutMap[x] & MAP_METATILE_ID_MASK) != FLOOR_EXIT_METATILE)
                 {
                     map[x] = layoutMap[x];
                 }
diff --git a/src/bg.c b/src/bg.c
index f73f5998d..571518650 100644
--- a/src/bg.c
+++ b/src/bg.c
@@ -1056,7 +1056,7 @@ void WriteSequenceToBgTilemapBuffer(u8 bg, u16 firstTileNum, u8 x, u8 y, u8 widt
                 for (x16 = x; x16 < (x + width); x16++)
                 {
                     CopyTileMapEntry(&firstTileNum, &((u16*)sGpuBgConfigs2[bg].tilemap)[(u16)GetTileMapIndexFromCoords(x16, y16, attribute, mode, mode2)], paletteSlot, 0, 0);
-                    firstTileNum = (firstTileNum & 0xFC00) + ((firstTileNum + tileNumDelta) & 0x3FF);
+                    firstTileNum = (firstTileNum & 0xFC00) + ((firstTileNum + tileNumDelta) & MAP_METATILE_ID_MASK);
                 }
             }
             break;
@@ -1067,7 +1067,7 @@ void WriteSequenceToBgTilemapBuffer(u8 bg, u16 firstTileNum, u8 x, u8 y, u8 widt
                 for (x16 = x; x16 < (x + width); x16++)
                 {
                     ((u8*)sGpuBgConfigs2[bg].tilemap)[(y16 * mode3) + x16] = firstTileNum;
-                    firstTileNum = (firstTileNum & 0xFC00) + ((firstTileNum + tileNumDelta) & 0x3FF);
+                    firstTileNum = (firstTileNum & 0xFC00) + ((firstTileNum + tileNumDelta) & MAP_METATILE_ID_MASK);
                 }
             }
             break;
diff --git a/src/decoration.c b/src/decoration.c
index 2ac49b98c..e5f3b6d46 100644
--- a/src/decoration.c
+++ b/src/decoration.c
@@ -1158,7 +1158,7 @@ void sub_8127B90(u16 mapX, u16 mapY, u8 decWidth, u8 decHeight, u16 decor)
     u16 i;
     u16 j;
     u16 behavior;
-    u16 flags;
+    u16 impassableFlag;
     u16 v0;
     u16 v1;
     s16 decLeft;
@@ -1173,11 +1173,11 @@ void sub_8127B90(u16 mapX, u16 mapY, u8 decWidth, u8 decHeight, u16 decor)
             behavior = GetBehaviorByMetatileId(0x200 + gDecorations[decor].tiles[i * decWidth + j]);
             if (MetatileBehavior_IsSecretBaseImpassable(behavior) == TRUE || (gDecorations[decor].permission != DECORPERM_PASS_FLOOR && (behavior >> 12)))
             {
-                flags = 0xc00;
+                impassableFlag = MAP_IMPASSABLE_MASK;
             }
             else
             {
-                flags = 0x000;
+                impassableFlag = 0x000;
             }
             if (gDecorations[decor].permission != DECORPERM_NA_WALL && MetatileBehavior_IsSecretBaseNorthWall(MapGridGetMetatileBehaviorAt(decLeft, decBottom)) == TRUE)
             {
@@ -1190,11 +1190,11 @@ void sub_8127B90(u16 mapX, u16 mapY, u8 decWidth, u8 decHeight, u16 decor)
             v1 = sub_8127B54(gDecorations[decor].id, i * decWidth + j);
             if (v1 != 0xFFFF)
             {
-                MapGridSetMetatileEntryAt(decLeft, decBottom, (gDecorations[decor].tiles[i * decWidth + j] + (0x200 | v0)) | flags | v1);
+                MapGridSetMetatileEntryAt(decLeft, decBottom, (gDecorations[decor].tiles[i * decWidth + j] + (0x200 | v0)) | impassableFlag | v1);
             }
             else
             {
-                MapGridSetMetatileIdAt(decLeft, decBottom, (gDecorations[decor].tiles[i * decWidth + j] + (0x200 | v0)) | flags);
+                MapGridSetMetatileIdAt(decLeft, decBottom, (gDecorations[decor].tiles[i * decWidth + j] + (0x200 | v0)) | impassableFlag);
             }
         }
     }
@@ -1502,7 +1502,7 @@ bool8 sub_812853C(u8 taskId, const struct Decoration *decoration)
                 {
                     curX = gTasks[taskId].data[0] + j;
                     behaviorAt = MapGridGetMetatileBehaviorAt(curX, curY);
-                    behaviorBy = GetBehaviorByMetatileId(0x200 + decoration->tiles[(mapY - 1 - i) * mapX + j]) & 0xf000;
+                    behaviorBy = GetBehaviorByMetatileId(0x200 + decoration->tiles[(mapY - 1 - i) * mapX + j]) & MAP_TILE_ELEVATION_MASK;
                     if (!sub_81284F4(behaviorAt, decoration))
                     {
                         return FALSE;
@@ -1527,7 +1527,7 @@ bool8 sub_812853C(u8 taskId, const struct Decoration *decoration)
                 {
                     curX = gTasks[taskId].data[0] + j;
                     behaviorAt = MapGridGetMetatileBehaviorAt(curX, curY);
-                    behaviorBy = GetBehaviorByMetatileId(0x200 + decoration->tiles[(mapY - 1 - i) * mapX + j]) & 0xf000;
+                    behaviorBy = GetBehaviorByMetatileId(0x200 + decoration->tiles[(mapY - 1 - i) * mapX + j]) & MAP_TILE_ELEVATION_MASK;
                     if (!MetatileBehavior_IsNormal(behaviorAt) && !sub_8128484(behaviorAt, behaviorBy))
                     {
                         return FALSE;
@@ -1547,7 +1547,7 @@ bool8 sub_812853C(u8 taskId, const struct Decoration *decoration)
             {
                 curX = gTasks[taskId].data[0] + j;
                 behaviorAt = MapGridGetMetatileBehaviorAt(curX, curY);
-                behaviorBy = GetBehaviorByMetatileId(0x200 + decoration->tiles[j]) & 0xf000;
+                behaviorBy = GetBehaviorByMetatileId(0x200 + decoration->tiles[j]) & MAP_TILE_ELEVATION_MASK;
                 if (!MetatileBehavior_IsNormal(behaviorAt) && !MetatileBehavior_IsSecretBaseNorthWall(behaviorAt))
                 {
                     return FALSE;
diff --git a/src/field_effect.c b/src/field_effect.c
index e7c0b39b9..07a7f9caf 100644
--- a/src/field_effect.c
+++ b/src/field_effect.c
@@ -2620,7 +2620,7 @@ static void sub_80B8874(u16 offs)
     dest = (u16 *)(VRAM + 0x140 + offs);
     for (i = 0; i < 0x140; i++, dest++)
     {
-        *dest = gFieldMoveStreaksTilemap[i] | 0xf000;
+        *dest = gFieldMoveStreaksTilemap[i] | MAP_TILE_ELEVATION_MASK;
     }
 }
 
diff --git a/src/field_specials.c b/src/field_specials.c
index 307f81399..c7d1f4367 100644
--- a/src/field_specials.c
+++ b/src/field_specials.c
@@ -887,8 +887,8 @@ static void PetalburgGymFunc(u8 a0, u16 a1)
     }
     for (i = 0; i < nDoors; i++)
     {
-        MapGridSetMetatileIdAt(x[i] + 7, y[i] + 7, a1 | 0xc00);
-        MapGridSetMetatileIdAt(x[i] + 7, y[i] + 8, (a1 + 8) | 0xc00);
+        MapGridSetMetatileIdAt(x[i] + 7, y[i] + 7, a1 | MAP_IMPASSABLE_MASK);
+        MapGridSetMetatileIdAt(x[i] + 7, y[i] + 8, (a1 + 8) | MAP_IMPASSABLE_MASK);
     }
     DrawWholeMapView();
 }
@@ -1100,7 +1100,7 @@ static void PCTurnOnEffect_1(s16 flag, s8 dx, s8 dy)
             tileId = 0x27e;
         }
     }
-    MapGridSetMetatileIdAt(gSaveBlock1Ptr->pos.x + dx + 7, gSaveBlock1Ptr->pos.y + dy + 7, tileId | 0xc00);
+    MapGridSetMetatileIdAt(gSaveBlock1Ptr->pos.x + dx + 7, gSaveBlock1Ptr->pos.y + dy + 7, tileId | MAP_IMPASSABLE_MASK);
 }
 
 void DoPCTurnOffEffect(void)
@@ -1141,7 +1141,7 @@ static void PCTurnOffEffect(void)
     {
         tileId = 0x259;
     }
-    MapGridSetMetatileIdAt(gSaveBlock1Ptr->pos.x + dx + 7, gSaveBlock1Ptr->pos.y + dy + 7, tileId | 0xc00);
+    MapGridSetMetatileIdAt(gSaveBlock1Ptr->pos.x + dx + 7, gSaveBlock1Ptr->pos.y + dy + 7, tileId | MAP_IMPASSABLE_MASK);
     DrawWholeMapView();
 }
 
@@ -1892,7 +1892,7 @@ static void sub_8139C80(u8 taskId)
             {
                 for (x = 0; x < 3; x++)
                 {
-                    MapGridSetMetatileIdAt(x + 8, y + 7, gUnknown_085B2BF4[y][data[0] % 3] | 0xC00);
+                    MapGridSetMetatileIdAt(x + 8, y + 7, gUnknown_085B2BF4[y][data[0] % 3] | MAP_IMPASSABLE_MASK);
                 }
             }
         }
@@ -1902,7 +1902,7 @@ static void sub_8139C80(u8 taskId)
             {
                 for (x = 0; x < 3; x++)
                 {
-                    MapGridSetMetatileIdAt(x + 8, y + 7, gUnknown_085B2C06[y][data[0] % 3] | 0xC00);
+                    MapGridSetMetatileIdAt(x + 8, y + 7, gUnknown_085B2C06[y][data[0] % 3] | MAP_IMPASSABLE_MASK);
                 }
             }
         }
diff --git a/src/fieldmap.c b/src/fieldmap.c
index cf5f0356e..8131fb01b 100644
--- a/src/fieldmap.c
+++ b/src/fieldmap.c
@@ -383,15 +383,15 @@ u8 MapGridGetZCoordAt(int x, int y)
         i = (x + 1) & 1;
         i += ((y + 1) & 1) * 2;
         block = gMapHeader.mapLayout->border[i];
-        block |= 0xc00;
+        block |= MAP_IMPASSABLE_MASK;
     }
 
-    if (block == 0x3ff)
+    if (block == MAP_UNDEFINED_METATILE_ID)
     {
         return 0;
     }
 
-    return block >> 12;
+    return block >> MAP_TILE_ELEVATION_SHIFT;
 }
 
 u8 MapGridIsImpassableAt(int x, int y)
@@ -411,13 +411,13 @@ u8 MapGridIsImpassableAt(int x, int y)
         i = (x + 1) & 1;
         i += ((y + 1) & 1) * 2;
         block = gMapHeader.mapLayout->border[i];
-        block |= 0xc00;
+        block |= MAP_IMPASSABLE_MASK;
     }
-    if (block == 0x3ff)
+    if (block == MAP_UNDEFINED_METATILE_ID)
     {
         return 1;
     }
-    return (block & 0xc00) >> 10;
+    return (block & MAP_IMPASSABLE_MASK) >> MAP_IMPASSABLE_SHIFT;
 }
 
 u32 MapGridGetMetatileIdAt(int x, int y)
@@ -439,18 +439,19 @@ u32 MapGridGetMetatileIdAt(int x, int y)
         mapLayout = gMapHeader.mapLayout;
         i = (x + 1) & 1;
         i += ((y + 1) & 1) * 2;
-        block = mapLayout->border[i] | 0xc00;
+        block = mapLayout->border[i] | MAP_IMPASSABLE_MASK;
     }
-    if (block == 0x3ff)
+    if (block == MAP_UNDEFINED_METATILE_ID)
     {
         border = gMapHeader.mapLayout->border;
         j = (x + 1) & 1;
         j += ((y + 1) & 1) * 2;
         block2 = gMapHeader.mapLayout->border[j];
-        block2 |= 0xc00;
-        return block2 & block;
+        // This OR is completely pointless.
+        block2 |= MAP_IMPASSABLE_MASK;
+        return block2 & MAP_METATILE_ID_MASK;
     }
-    return block & 0x3ff;
+    return block & MAP_METATILE_ID_MASK;
 }
 
 u32 MapGridGetMetatileBehaviorAt(int x, int y)
@@ -464,7 +465,7 @@ u8 MapGridGetMetatileLayerTypeAt(int x, int y)
 {
     u16 metatile;
     metatile = MapGridGetMetatileIdAt(x, y);
-    return (GetBehaviorByMetatileId(metatile) & 0xf000) >> 12;
+    return (GetBehaviorByMetatileId(metatile) & MAP_TILE_ELEVATION_MASK) >> MAP_TILE_ELEVATION_SHIFT;
 }
 
 void MapGridSetMetatileIdAt(int x, int y, u16 metatile)
@@ -474,7 +475,7 @@ void MapGridSetMetatileIdAt(int x, int y, u16 metatile)
      && y >= 0 && y < gBackupMapLayout.height)
     {
         i = x + y * gBackupMapLayout.width;
-        gBackupMapLayout.map[i] = (gBackupMapLayout.map[i] & 0xf000) | (metatile & 0xfff);
+        gBackupMapLayout.map[i] = (gBackupMapLayout.map[i] & MAP_TILE_ELEVATION_MASK) | (metatile & ~MAP_TILE_ELEVATION_MASK);
     }
 }
 
@@ -654,7 +655,7 @@ int GetMapBorderIdAt(int x, int y)
         i = gBackupMapLayout.width;
         i *= y;
         block = gBackupMapLayout.map[x + i];
-        if (block == 0x3ff)
+        if (block == MAP_UNDEFINED_METATILE_ID)
         {
             goto fail;
         }
@@ -664,8 +665,8 @@ int GetMapBorderIdAt(int x, int y)
         mapLayout = gMapHeader.mapLayout;
         j = (x + 1) & 1;
         j += ((y + 1) & 1) * 2;
-        block2 = 0xc00 | mapLayout->border[j];
-        if (block2 == 0x3ff)
+        block2 = MAP_IMPASSABLE_MASK | mapLayout->border[j];
+        if (block2 == MAP_UNDEFINED_METATILE_ID)
         {
             goto fail;
         }
@@ -921,7 +922,7 @@ void sub_8088B94(int x, int y, int a2)
     if (x >= 0 && x < gBackupMapLayout.width && y >= 0 && y < gBackupMapLayout.height)
     {
         if (a2 != 0)
-            gBackupMapLayout.map[x + gBackupMapLayout.width * y] |= 0xC00;
+            gBackupMapLayout.map[x + gBackupMapLayout.width * y] |= MAP_IMPASSABLE_MASK;
         else
             gBackupMapLayout.map[x + gBackupMapLayout.width * y] &= 0xF3FF;
     }
@@ -937,7 +938,7 @@ static bool8 SkipCopyingMetatileFromSavedMap(u16* mapMetatilePtr, u16 mapWidth,
     else
         mapMetatilePtr += mapWidth;
 
-    if (sub_80FADE4(*mapMetatilePtr & 0x3FF, yMode) == 1)
+    if (sub_80FADE4(*mapMetatilePtr & MAP_METATILE_ID_MASK, yMode) == 1)
         return TRUE;
     return FALSE;
 }
diff --git a/src/fldeff_escalator.c b/src/fldeff_escalator.c
index 3d00fb162..4a1fb0fd5 100644
--- a/src/fldeff_escalator.c
+++ b/src/fldeff_escalator.c
@@ -7,7 +7,7 @@
 
 static EWRAM_DATA u8 sEscalatorAnim_TaskId = 0;
 
-static void sub_80E12E8(u8 taskId, const s16 *list, u16 c)
+static void sub_80E12E8(u8 taskId, const s16 *list, u16 isImpassableFlag)
 {
     s16 r5 = gTasks[taskId].data[4] - 1;
     s16 r3 = gTasks[taskId].data[5] - 1;
@@ -26,9 +26,9 @@ static void sub_80E12E8(u8 taskId, const s16 *list, u16 c)
                 if (list[r4] == metatileId)
                 {
                     if (r4 != 2)
-                        MapGridSetMetatileIdAt(r5 + x, r3 + y, c | list[r4 + 1]);
+                        MapGridSetMetatileIdAt(r5 + x, r3 + y, isImpassableFlag | list[r4 + 1]);
                     else
-                        MapGridSetMetatileIdAt(r5 + x, r3 + y, c | list[0]);
+                        MapGridSetMetatileIdAt(r5 + x, r3 + y, isImpassableFlag | list[0]);
                 }
             }
         }
@@ -44,9 +44,9 @@ static void sub_80E12E8(u8 taskId, const s16 *list, u16 c)
                 if (list[2 - r4] == metatileId)
                 {
                     if (r4 != 2)
-                        MapGridSetMetatileIdAt(r5 + x, r3 + y, c | list[1 - r4]);
+                        MapGridSetMetatileIdAt(r5 + x, r3 + y, isImpassableFlag | list[1 - r4]);
                     else
-                        MapGridSetMetatileIdAt(r5 + x, r3 + y, c | list[2]);
+                        MapGridSetMetatileIdAt(r5 + x, r3 + y, isImpassableFlag | list[2]);
                 }
             }
         }
@@ -76,13 +76,13 @@ static void sub_80E1444(u8 taskId)
             sub_80E12E8(taskId, gUnknown_08589AC0, 0);
             break;
         case 2:
-            sub_80E12E8(taskId, gUnknown_08589AC6, 0xC00);
+            sub_80E12E8(taskId, gUnknown_08589AC6, MAP_IMPASSABLE_MASK);
             break;
         case 3:
             sub_80E12E8(taskId, gUnknown_08589ACC, 0);
             break;
         case 4:
-            sub_80E12E8(taskId, gUnknown_08589AD2, 0xC00);
+            sub_80E12E8(taskId, gUnknown_08589AD2, MAP_IMPASSABLE_MASK);
             break;
         case 5:
             sub_80E12E8(taskId, gUnknown_08589AD8, 0);
diff --git a/src/scrcmd.c b/src/scrcmd.c
index 51d96ff2e..9bafac41a 100644
--- a/src/scrcmd.c
+++ b/src/scrcmd.c
@@ -2028,14 +2028,14 @@ bool8 ScrCmd_setmetatile(struct ScriptContext *ctx)
     u16 x = VarGet(ScriptReadHalfword(ctx));
     u16 y = VarGet(ScriptReadHalfword(ctx));
     u16 tileId = VarGet(ScriptReadHalfword(ctx));
-    u16 v8 = VarGet(ScriptReadHalfword(ctx));
+    u16 isImpassable = VarGet(ScriptReadHalfword(ctx));
 
     x += 7;
     y += 7;
-    if (!v8)
+    if (!isImpassable)
         MapGridSetMetatileIdAt(x, y, tileId);
     else
-        MapGridSetMetatileIdAt(x, y, tileId | 0xC00);
+        MapGridSetMetatileIdAt(x, y, tileId | MAP_IMPASSABLE_MASK);
     return FALSE;
 }
 
diff --git a/src/secret_base.c b/src/secret_base.c
index adcab9cbc..488f49377 100644
--- a/src/secret_base.c
+++ b/src/secret_base.c
@@ -259,7 +259,7 @@ void sub_80E8CB0(s16 *xPtr, s16 *yPtr, u16 tile)
     {
         for (x = 0; x < mapLayout->width; x ++)
         {
-            if ((mapLayout->map[y * mapLayout->width + x] & 0x3ff) == tile)
+            if ((mapLayout->map[y * mapLayout->width + x] & MAP_METATILE_ID_MASK) == tile)
             {
                 *xPtr = x;
                 *yPtr = y;
@@ -282,7 +282,7 @@ void sub_80E8D4C(void)
     {
         if (gUnknown_0858CFCC[i].tile1 == tile)
         {
-            MapGridSetMetatileIdAt(x, y, gUnknown_0858CFCC[i].tile2 | 0xC00);
+            MapGridSetMetatileIdAt(x, y, gUnknown_0858CFCC[i].tile2 | MAP_IMPASSABLE_MASK);
             CurrentMapDrawMetatileAt(x, y);
             return;
         }
@@ -291,7 +291,7 @@ void sub_80E8D4C(void)
     {
         if (gUnknown_0858CFCC[i].tile2 == tile)
         {
-            MapGridSetMetatileIdAt(x, y, gUnknown_0858CFCC[i].tile1 | 0xC00);
+            MapGridSetMetatileIdAt(x, y, gUnknown_0858CFCC[i].tile1 | MAP_IMPASSABLE_MASK);
             CurrentMapDrawMetatileAt(x, y);
             return;
         }
@@ -352,7 +352,7 @@ void sub_80E8EE0(struct MapEvents const *events)
                     {
                         if (gUnknown_0858CFCC[i].tile1 == tile_id)
                         {
-                            MapGridSetMetatileIdAt(x, y, gUnknown_0858CFCC[i].tile2 | 0xc00);
+                            MapGridSetMetatileIdAt(x, y, gUnknown_0858CFCC[i].tile2 | MAP_IMPASSABLE_MASK);
                             break;
                         }
                     }
@@ -434,7 +434,7 @@ void sub_80E9108(void)
     sub_80E8CB0(&x, &y, 0x220);
     x += 7;
     y += 7;
-    MapGridSetMetatileIdAt(x, y, 0x220 | 0xC00);
+    MapGridSetMetatileIdAt(x, y, 0x220 | MAP_IMPASSABLE_MASK);
     CurrentMapDrawMetatileAt(x, y);
     pal_fill_black();
     CreateTask(sub_80E90C8, 0);
@@ -492,12 +492,12 @@ void sub_80E9238(u8 flagIn)
         if (curBaseId != 0)
         {
             sub_80E8CB0(&x, &y, 0x220);
-            MapGridSetMetatileIdAt(x + 7, y + 7, 0x221 | 0xc00);
+            MapGridSetMetatileIdAt(x + 7, y + 7, 0x221 | MAP_IMPASSABLE_MASK);
         }
         else if (flagIn == 1 && VarGet(VAR_0x4089) == 1)
         {
             sub_80E8CB0(&x, &y, 0x220);
-            MapGridSetMetatileIdAt(x + 7, y + 7, 0x20a | 0xc00);
+            MapGridSetMetatileIdAt(x + 7, y + 7, 0x20a | MAP_IMPASSABLE_MASK);
         }
     }
 }
@@ -791,7 +791,7 @@ void sub_80E9AD0(void)
             {
                 if (gUnknown_0858CFCC[j].tile2 == tile)
                 {
-                    MapGridSetMetatileIdAt(events->bgEvents[i].x + 7, events->bgEvents[i].y + 7, gUnknown_0858CFCC[j].tile1 | 0xc00);
+                    MapGridSetMetatileIdAt(events->bgEvents[i].x + 7, events->bgEvents[i].y + 7, gUnknown_0858CFCC[j].tile1 | MAP_IMPASSABLE_MASK);
                     break;
                 }
             }
diff --git a/src/tv.c b/src/tv.c
index ee3614e83..6ab91ac07 100644
--- a/src/tv.c
+++ b/src/tv.c
@@ -39,6 +39,7 @@
 #include "tv.h"
 #include "data2.h"
 #include "constants/layouts.h"
+#include "constants/metatile_behaviors.h"
 
 // Static type declarations
 
@@ -853,9 +854,9 @@ void SetTVMetatilesOnMap(int width, int height, u16 tileId)
     {
         for (x = 0; x < width; x ++)
         {
-            if (MapGridGetMetatileBehaviorAt(x, y) == 0x86) // is this tile a TV?
+            if (MapGridGetMetatileBehaviorAt(x, y) == MB_TELEVISION)
             {
-                MapGridSetMetatileIdAt(x, y, tileId | 0xc00);
+                MapGridSetMetatileIdAt(x, y, tileId | MAP_IMPASSABLE_MASK);
             }
         }
     }