Mapgen caves: Re-order generation to fix cavern bug

Previously, caverns confused tunnel generation causing biome top and filler
nodes to appear in caverns.
Split 'generateCaves()' into 2 functions to separate tunnel and large
randomwalk cave generation.
In each mapgen re-order cave generation to generate tunnels before caverns.

1 files changed, 12 insertions, 7 deletions

diff --git a/src/mapgen/mapgen_v7.cpp b/src/mapgen/mapgen_v7.cpp
index c83a5105d..23e8dbdd2 100644
--- a/src/mapgen/mapgen_v7.cpp
+++ b/src/mapgen/mapgen_v7.cpp
@@ -313,20 +313,25 @@ void MapgenV7::makeChunk(BlockMakeData *data)
 	biomegen->calcBiomeNoise(node_min);
 	generateBiomes();
 
-	// Generate caverns, tunnels and classic caves
+	// Generate tunnels, caverns and large randomwalk caves
 	if (flags & MG_CAVES) {
-		bool near_cavern = false;
+		// Generate tunnels first as caverns confuse them
+		generateCavesNoiseIntersection(stone_surface_max_y);
+
 		// Generate caverns
+		bool near_cavern = false;
 		if (spflags & MGV7_CAVERNS)
-			near_cavern = generateCaverns(stone_surface_max_y);
-		// Generate tunnels and classic caves
+			near_cavern = generateCavernsNoise(stone_surface_max_y);
+
+		// Generate large randomwalk caves
 		if (near_cavern)
-			// Disable classic caves in this mapchunk by setting
+			// Disable large randomwalk caves in this mapchunk by setting
 			// 'large cave depth' to world base. Avoids excessive liquid in
 			// large caverns and floating blobs of overgenerated liquid.
-			generateCaves(stone_surface_max_y, -MAX_MAP_GENERATION_LIMIT);
+			generateCavesRandomWalk(stone_surface_max_y,
+				-MAX_MAP_GENERATION_LIMIT);
 		else
-			generateCaves(stone_surface_max_y, large_cave_depth);
+			generateCavesRandomWalk(stone_surface_max_y, large_cave_depth);
 	}
 
 	// Generate dungeons