Fix MapgenV6::generateCaves possible division by 0 and misc. cosmetic fixes

src/mapgen_v6.cpp

@@ -928,20 +928,20 @@ void MapgenV6::growGrass() {
 
 void MapgenV6::defineCave(Cave &cave, PseudoRandom ps,
 						 v3s16 node_min, bool large_cave) {
-		cave.min_tunnel_diameter = 2;
+	cave.min_tunnel_diameter = 2;
-		cave.max_tunnel_diameter = ps.range(2,6);
+	cave.max_tunnel_diameter = ps.range(2,6);
-		cave.dswitchint = ps.range(1,14);
+	cave.dswitchint = ps.range(1,14);
-		cave.flooded = true; //large_cave && ps.range(0,4);
+	cave.flooded = true; //large_cave && ps.range(0,4);
-		if(large_cave){
+	if (large_cave){
-			cave.part_max_length_rs = ps.range(2,4);
+		cave.part_max_length_rs = ps.range(2,4);
-			cave.tunnel_routepoints = ps.range(5, ps.range(15,30));
+		cave.tunnel_routepoints = ps.range(5, ps.range(15,30));
-			cave.min_tunnel_diameter = 5;
+		cave.min_tunnel_diameter = 5;
-			cave.max_tunnel_diameter = ps.range(7, ps.range(8,24));
+		cave.max_tunnel_diameter = ps.range(7, ps.range(8,24));
-		} else {
+	} else {
-			cave.part_max_length_rs = ps.range(2,9);
+		cave.part_max_length_rs = ps.range(2,9);
-			cave.tunnel_routepoints = ps.range(10, ps.range(15,30));
+		cave.tunnel_routepoints = ps.range(10, ps.range(15,30));
-		}
+	}
-		cave.large_cave_is_flat = (ps.range(0,1) == 0);
+	cave.large_cave_is_flat = (ps.range(0,1) == 0);
 }
 
 
@@ -1120,7 +1120,13 @@ void MapgenV6::generateCaves(int max_stone_y) {
 				rp.Z = ar.Z-1;
 			vec = rp - orp;
 
-			for(float f=0; f<1.0; f+=1.0/vec.getLength())
+			float veclen = vec.getLength();
+			// As odd as it sounds, veclen is *exactly*
+			// 0.0 sometimes, causing a FPE
+			if (veclen == 0.0)
+				veclen = 1.0;
+
+			for(float f=0; f<1.0; f+=1.0/veclen)
 			{
 				v3f fp = orp + vec * f;
 				fp.X += 0.1*ps.range(-10,10);

src/nodedef.cpp

@@ -822,6 +822,7 @@ private:
 	std::map<std::string, content_t> m_name_id_mapping_with_aliases;
 	// A mapping from groups to a list of content_ts (and their levels)
 	// that belong to it.  Necessary for a direct lookup in getIds().
+	// Note: Not serialized.
 	std::map<std::string, GroupItems> m_group_to_items;
 };
 

src/scriptapi.cpp

@@ -727,7 +727,7 @@ static int l_register_ore(lua_State *L)
 	
 	if (ore->clust_scarcity <= 0 || ore->clust_num_ores <= 0) {
 		errorstream << "register_ore: clust_scarcity and clust_num_ores"
-			"must be greater than 0";
+			" must be greater than 0" << std::endl;
 		delete ore;
 		return 0;
 	}