overhaul worldgen

src/worldgen.h

@@ -3,7 +3,12 @@
 
 #include <stdint.h>
 
+// For best performance, chunk_size should be a power of 2
 #define chunk_size 8
+// Terrain low point - should start a bit below sea level for rivers/lakes
+#define terrain_base_height 60
+// Center point of cave generation
+#define cave_base_depth 24
 
 uint32_t getChunkHash (short x, short z);
 int getHeightAt (int rx, int rz, int _x, int _z, uint32_t chunk_hash);