Codechange: use unique_ptr over CallocT and avoid copying table

src/landscape.cpp

@@ -93,7 +93,7 @@ static const uint TILE_UPDATE_FREQUENCY = 1 << TILE_UPDATE_FREQUENCY_LOG;  ///<
  * @ingroup SnowLineGroup
  * @see GetSnowLine() GameCreationSettings
  */
-static SnowLine *_snow_line = nullptr;
+static std::unique_ptr<SnowLine> _snow_line;
 
 /**
  * Map 2D viewport or smallmap coordinate to 3D world or tile coordinate.
@@ -584,21 +584,12 @@ bool IsSnowLineSet()
 
 /**
  * Set a variable snow line, as loaded from a newgrf file.
- * @param table the 12 * 32 byte table containing the snowline for each day
+ * @param snow_line The new snow line configuration.
  * @ingroup SnowLineGroup
  */
-void SetSnowLine(uint8_t table[SNOW_LINE_MONTHS][SNOW_LINE_DAYS])
+void SetSnowLine(std::unique_ptr<SnowLine> &&snow_line)
 {
-	_snow_line = CallocT<SnowLine>(1);
+	_snow_line = std::move(snow_line);
-	_snow_line->lowest_value = 0xFF;
-	memcpy(_snow_line->table, table, sizeof(_snow_line->table));
-
-	for (uint i = 0; i < SNOW_LINE_MONTHS; i++) {
-		for (uint j = 0; j < SNOW_LINE_DAYS; j++) {
-			_snow_line->highest_value = std::max(_snow_line->highest_value, table[i][j]);
-			_snow_line->lowest_value = std::min(_snow_line->lowest_value, table[i][j]);
-		}
-	}
 }
 
 /**
@@ -640,7 +631,6 @@ uint8_t LowestSnowLine()
  */
 void ClearSnowLine()
 {
-	free(_snow_line);
 	_snow_line = nullptr;
 }
 

src/landscape.h

@@ -22,12 +22,12 @@ static const uint SNOW_LINE_DAYS   = 32; ///< Number of days in each month in th
  */
 struct SnowLine {
 	uint8_t table[SNOW_LINE_MONTHS][SNOW_LINE_DAYS]; ///< Height of the snow line each day of the year
-	uint8_t highest_value; ///< Highest snow line of the year
+	uint8_t highest_value = 0; ///< Highest snow line of the year
-	uint8_t lowest_value;  ///< Lowest snow line of the year
+	uint8_t lowest_value = UINT8_MAX; ///< Lowest snow line of the year
 };
 
 bool IsSnowLineSet();
-void SetSnowLine(uint8_t table[SNOW_LINE_MONTHS][SNOW_LINE_DAYS]);
+void SetSnowLine(std::unique_ptr<SnowLine> &&snow_line);
 uint8_t GetSnowLine();
 uint8_t HighestSnowLine();
 uint8_t LowestSnowLine();

src/newgrf.cpp

@@ -2873,24 +2873,28 @@ static ChangeInfoResult GlobalVarChangeInfo(uint gvid, int numinfo, int prop, By
 				} else if (buf.Remaining() < SNOW_LINE_MONTHS * SNOW_LINE_DAYS) {
 					GrfMsg(1, "GlobalVarChangeInfo: Not enough entries set in the snowline table ({})", buf.Remaining());
 				} else {
-					uint8_t table[SNOW_LINE_MONTHS][SNOW_LINE_DAYS];
+					auto snow_line = std::make_unique<SnowLine>();
 
 					for (uint i = 0; i < SNOW_LINE_MONTHS; i++) {
 						for (uint j = 0; j < SNOW_LINE_DAYS; j++) {
-							table[i][j] = buf.ReadByte();
+							uint8_t &level = snow_line->table[i][j];
+							level = buf.ReadByte();
 							if (_cur.grffile->grf_version >= 8) {
-								if (table[i][j] != 0xFF) table[i][j] = table[i][j] * (1 + _settings_game.construction.map_height_limit) / 256;
+								if (level != 0xFF) level = level * (1 + _settings_game.construction.map_height_limit) / 256;
 							} else {
-								if (table[i][j] >= 128) {
+								if (level >= 128) {
 									/* no snow */
-									table[i][j] = 0xFF;
+									level = 0xFF;
 								} else {
-									table[i][j] = table[i][j] * (1 + _settings_game.construction.map_height_limit) / 128;
+									level = level * (1 + _settings_game.construction.map_height_limit) / 128;
 								}
 							}
+
+							snow_line->highest_value = std::max(snow_line->highest_value, level);
+							snow_line->lowest_value = std::min(snow_line->lowest_value, level);
 						}
 					}
-					SetSnowLine(table);
+					SetSnowLine(std::move(snow_line));
 				}
 				break;