Feature: auto-detect map height limit based on generated map

This opens up the true power of the TGP terrain generator, as it
is no longer constrainted by an arbitrary low map height limit,
especially for extreme terrain types.

In other words: on a 1kx1k map with "Alpinist" terrain type, the
map is now really hilly with default settings.

People can still manually limit the map height if they so wish,
and after the terrain generation the limit is stored in the
savegame as if the user set it.

Cheats still allow you to change this value.

1 files changed, 15 insertions, 0 deletions

diff --git a/src/genworld.cpp b/src/genworld.cpp
index 0bd64f896..d357a1516 100644
--- a/src/genworld.cpp
+++ b/src/genworld.cpp
@@ -33,6 +33,7 @@
 #include "game/game_instance.hpp"
 #include "string_func.h"
 #include "thread.h"
+#include "tgp.h"
 
 #include "safeguards.h"
 
@@ -285,6 +286,20 @@ void GenerateWorld(GenWorldMode mode, uint size_x, uint size_y, bool reset_setti
 	InitializeGame(_gw.size_x, _gw.size_y, true, reset_settings);
 	PrepareGenerateWorldProgress();
 
+	if (_settings_game.construction.map_height_limit == 0) {
+		uint estimated_height = 0;
+
+		if (_gw.mode == GWM_EMPTY && _game_mode != GM_MENU) {
+			estimated_height = _settings_game.game_creation.se_flat_world_height;
+		} else if (_settings_game.game_creation.land_generator == LG_TERRAGENESIS) {
+			estimated_height = GetEstimationTGPMapHeight();
+		} else {
+			estimated_height = 0;
+		}
+
+		_settings_game.construction.map_height_limit = std::max(MAP_HEIGHT_LIMIT_AUTO_MINIMUM, std::min(MAX_MAP_HEIGHT_LIMIT, estimated_height + MAP_HEIGHT_LIMIT_AUTO_CEILING_ROOM));
+	}
+
 	/* Load the right landscape stuff, and the NewGRFs! */
 	GfxLoadSprites();
 	LoadStringWidthTable();