Mgv6/treegen: (Re)Add fallback nodes for compatibility with subgames

src/mapgen_v6.cpp

@@ -108,6 +108,14 @@ MapgenV6::MapgenV6(int mapgenid, MapgenParams *params, EmergeManager *emerge)
 		c_mossycobble = c_cobble;
 	if (c_stair_cobble == CONTENT_IGNORE)
 		c_stair_cobble = c_cobble;
+	if (c_dirt_with_snow == CONTENT_IGNORE)
+		c_dirt_with_snow = c_dirt_with_grass;
+	if (c_snow == CONTENT_IGNORE)
+		c_snow = CONTENT_AIR;
+	if (c_snowblock == CONTENT_IGNORE)
+		c_snowblock = c_dirt_with_grass;
+	if (c_ice == CONTENT_IGNORE)
+		c_ice = c_water_source;
 }
 
 

src/treegen.cpp

@@ -656,8 +656,15 @@ void make_jungletree(MMVManip &vmanip, v3s16 p0, INodeDefManager *ndef, int seed
 		and in games that have saplings; both are deprecated but not
 		replaced yet
 	*/
-	MapNode treenode(ndef->getId("mapgen_jungletree"));
-	MapNode leavesnode(ndef->getId("mapgen_jungleleaves"));
+	content_t c_tree   = ndef->getId("mapgen_jungletree");
+	content_t c_leaves = ndef->getId("mapgen_jungleleaves");
+	if (c_tree == CONTENT_IGNORE)
+		c_tree = ndef->getId("mapgen_tree");
+	if (c_leaves == CONTENT_IGNORE)
+		c_leaves = ndef->getId("mapgen_leaves");
+
+	MapNode treenode(c_tree);
+	MapNode leavesnode(c_leaves);
 
 	PseudoRandom pr(seed);
 	for (s16 x= -1; x <= 1; x++)
@@ -748,9 +755,19 @@ void make_pine_tree(MMVManip &vmanip, v3s16 p0, INodeDefManager *ndef, int seed)
 		and in games that have saplings; both are deprecated but not
 		replaced yet
 	*/
-	MapNode treenode(ndef->getId("mapgen_pinetree"));
-	MapNode leavesnode(ndef->getId("mapgen_pine_needles"));
-	MapNode snownode(ndef->getId("mapgen_snow"));
+	content_t c_tree   = ndef->getId("mapgen_pinetree");
+	content_t c_leaves = ndef->getId("mapgen_pine_needles");
+	content_t c_snow = ndef->getId("mapgen_snow");
+	if (c_tree == CONTENT_IGNORE)
+		c_tree = ndef->getId("mapgen_tree");
+	if (c_leaves == CONTENT_IGNORE)
+		c_leaves = ndef->getId("mapgen_leaves");
+	if (c_snow == CONTENT_IGNORE)
+		c_snow = CONTENT_AIR;
+
+	MapNode treenode(c_tree);
+	MapNode leavesnode(c_leaves);
+	MapNode snownode(c_snow);
 
 	PseudoRandom pr(seed);
 	s16 trunk_h = pr.range(9, 13);