Adjust baseline for arctic snowline dynamic width setting to lower value

src/landscape.cpp

@@ -106,7 +106,6 @@ byte _cached_snowline = 0;
 byte _cached_highest_snowline = 0;
 byte _cached_lowest_snowline = 0;
 byte _cached_tree_placement_highest_snowline = 0;
-byte _cached_tree_placement_lowest_snowline = 0;
 
 /**
  * Map 2D viewport or smallmap coordinate to 3D world or tile coordinate.
@@ -690,9 +689,8 @@ void UpdateCachedSnowLineBounds()
 	_cached_highest_snowline = _snow_line == nullptr ? _settings_game.game_creation.snow_line_height : _snow_line->highest_value;
 	_cached_lowest_snowline = _snow_line == nullptr ? _settings_game.game_creation.snow_line_height : _snow_line->lowest_value;
 
-	uint snowline_delta = (((100 - _settings_game.construction.trees_around_snow_line_dynamic_range) * (HighestSnowLine() - LowestSnowLine())) + 50) / 100;
-	_cached_tree_placement_highest_snowline = HighestSnowLine() - ((snowline_delta + 1) / 2);
-	_cached_tree_placement_lowest_snowline = LowestSnowLine() + (snowline_delta / 2);
+	uint snowline_range = ((_settings_game.construction.trees_around_snow_line_dynamic_range * (HighestSnowLine() - LowestSnowLine())) + 50) / 100;
+	_cached_tree_placement_highest_snowline = LowestSnowLine() + snowline_range;
 }
 
 /**

src/landscape.h

@@ -59,8 +59,7 @@ inline byte HighestTreePlacementSnowLine()
 
 inline byte LowestTreePlacementSnowLine()
 {
-	extern byte _cached_tree_placement_lowest_snowline;
-	return _cached_tree_placement_lowest_snowline;
+	return LowestSnowLine();
 }
 
 int GetSlopeZInCorner(Slope tileh, Corner corner);

src/lang/english.txt

@@ -2205,7 +2205,7 @@ STR_CONFIG_SETTING_TREES_AROUND_SNOWLINE_HELPTEXT               :Adjust placemen
 STR_CONFIG_SETTING_TREES_AROUND_SNOWLINE_RANGE                  :Arctic tree range: {STRING2}
 STR_CONFIG_SETTING_TREES_AROUND_SNOWLINE_RANGE_HELPTEXT         :Approximate range of arctic trees around snow line
 STR_CONFIG_SETTING_TREES_AROUND_SNOWLINE_DYNAMIC_RANGE          :Seasonal snow line width for arctic trees: {STRING2}
-STR_CONFIG_SETTING_TREES_AROUND_SNOWLINE_DYNAMIC_RANGE_HELPTEXT :When using a seasonally variable snow line, what percentage of the snow line variation to use as the snow line for arctic tree placement. 0% uses the mid-point between summer and winter snow lines, 100% uses the whole range between the summer and winter snow lines.
+STR_CONFIG_SETTING_TREES_AROUND_SNOWLINE_DYNAMIC_RANGE_HELPTEXT :When using a seasonally variable snow line, what percentage of the snow line variation to use as the snow line for arctic tree placement. 0% uses the lower (winter) snow line, 100% uses the whole range between the summer and winter snow lines.
 
 STR_CONFIG_SETTING_BUILD_PUBLIC_ROADS                           :Build public roads connecting towns: {STRING2}
 STR_CONFIG_SETTING_BUILD_PUBLIC_ROADS_HELPTEXT                  :Generates public roads which connect the towns. Takes a bit of time on bigger maps. 'Build and avoid' generates roads which avoid curves and result in very grid-like connections.