From 9599d63f455607d7dc5713411b4872e978775e4f Mon Sep 17 00:00:00 2001
From: Alexander Batalov <alex.batalov@gmail.com>
Date: Tue, 20 Dec 2022 15:09:01 +0300
Subject: [PATCH] Review roof_fill_off

---
 src/tile.cc | 45 ++++++++++++++++++++-------------------------
 1 file changed, 20 insertions(+), 25 deletions(-)

diff --git a/src/tile.cc b/src/tile.cc
index 16682db..e3165a6 100644
--- a/src/tile.cc
+++ b/src/tile.cc
@@ -52,7 +52,7 @@ static void tileSetBorder(int windowWidth, int windowHeight, int hexGridWidth, i
 static void tileRefreshMapper(Rect* rect, int elevation);
 static void tileRefreshGame(Rect* rect, int elevation);
 static void roof_fill_on(int x, int y, int elevation);
-static void sub_4B23DC(int x, int y, int elevation);
+static void roof_fill_off(int x, int y, int elevation);
 static void tileRenderRoof(int fid, int x, int y, Rect* rect, int light);
 static void _draw_grid(int tile, int elevation, Rect* rect);
 static void tileRenderFloor(int fid, int x, int y, Rect* rect);
@@ -1271,37 +1271,32 @@ void _tile_fill_roof(int a1, int a2, int elevation, int a4)
     if (a4) {
         roof_fill_on(a1, a2, elevation);
     } else {
-        sub_4B23DC(a1, a2, elevation);
+        roof_fill_off(a1, a2, elevation);
     }
 }
 
 // 0x4B23DC
-static void sub_4B23DC(int a1, int a2, int elevation)
+static void roof_fill_off(int x, int y, int elevation)
 {
-    while ((a1 >= 0 && a1 < gSquareGridWidth) && (a2 >= 0 && a2 < gSquareGridHeight)) {
-        int squareTile = gSquareGridWidth * a2 + a1;
-        int value = gTileSquares[elevation]->field_0[squareTile];
-        int upper = (value >> 16) & 0xFFFF;
+    if (x >= 0 && x < gSquareGridWidth && y >= 0 && y < gSquareGridHeight) {
+        int squareTileIndex = gSquareGridWidth * y + x;
+        int squareTile = gTileSquares[elevation]->field_0[squareTileIndex];
+        int roof = (squareTile >> 16) & 0xFFFF;
 
-        int id = upper & 0xFFF;
-        if (buildFid(OBJ_TYPE_TILE, id, 0, 0, 0) == buildFid(OBJ_TYPE_TILE, 1, 0, 0, 0)) {
-            break;
+        int id = roof & 0xFFF;
+        if (buildFid(OBJ_TYPE_TILE, id, 0, 0, 0) != buildFid(OBJ_TYPE_TILE, 1, 0, 0, 0)) {
+            int flag = (roof & 0xF000) >> 12;
+            if ((flag & 0x03) == 0) {
+                flag |= 0x01;
+
+                gTileSquares[elevation]->field_0[squareTileIndex] = (squareTile & 0xFFFF) | (((flag << 12) | id) << 16);
+
+                roof_fill_off(x - 1, y, elevation);
+                roof_fill_off(x + 1, y, elevation);
+                roof_fill_off(x, y - 1, elevation);
+                roof_fill_off(x, y + 1, elevation);
+            }
         }
-
-        int flag = (upper & 0xF000) >> 12;
-        if ((flag & 0x03) != 0) {
-            break;
-        }
-
-        flag |= 0x01;
-
-        gTileSquares[elevation]->field_0[squareTile] = (value & 0xFFFF) | (((flag << 12) | id) << 16);
-
-        sub_4B23DC(a1 - 1, a2, elevation);
-        sub_4B23DC(a1 + 1, a2, elevation);
-        sub_4B23DC(a1, a2 - 1, elevation);
-
-        a2++;
     }
 }