Mapgen: Add global 'decorations' flag

Flag is set by default in MapgenParams
The global 'trees' flag remains but is now
undocumented and unset by default in MapgenParams
Add mgv6_spflag 'trees' set by default in
defaultsettings.cpp to affect new worlds only
This is automatically backwards
compatible for existing worlds

11 files changed, 37 insertions, 26 deletions

diff --git a/builtin/settingtypes.txt b/builtin/settingtypes.txt
index bf452915a..cb38ec118 100644
--- a/builtin/settingtypes.txt
+++ b/builtin/settingtypes.txt
@@ -829,10 +829,11 @@ max_block_generate_distance (Max block generate distance) int 6
 map_generation_limit (Map generation limit) int 31000 0 31000
 
 #    Global map generation attributes.
-#    The 'trees' flag only has effect in mgv6.
+#    In Mapgen v6 the 'decorations' flag controls all decorations except trees
+#    and junglegrass, in all other mapgens this flag controls all decorations.
 #    Flags that are not specified in the flag string are not modified from the default.
 #    Flags starting with "no" are used to explicitly disable them.
-mg_flags (Mapgen flags) flags trees,caves,dungeons,light trees,caves,dungeons,light,notrees,nocaves,nodungeons,nolight
+mg_flags (Mapgen flags) flags caves,dungeons,light,decorations caves,dungeons,light,decorations,nocaves,nodungeons,nolight,nodecorations
 
 [**Advanced]
 
@@ -889,7 +890,7 @@ mgv5_np_cave2 (Mapgen v5 cave2 noise parameters) noise_params 0, 12, (50, 50, 50
 #    When snowbiomes are enabled jungles are enabled and the jungles flag is ignored.
 #    Flags that are not specified in the flag string are not modified from the default.
 #    Flags starting with "no" are used to explicitly disable them.
-mgv6_spflags (Mapgen v6 flags) flags jungles,biomeblend,mudflow,snowbiomes jungles,biomeblend,mudflow,snowbiomes,flat,nojungles,nobiomeblend,nomudflow,nosnowbiomes,noflat
+mgv6_spflags (Mapgen v6 flags) flags jungles,biomeblend,mudflow,snowbiomes,trees jungles,biomeblend,mudflow,snowbiomes,flat,trees,nojungles,nobiomeblend,nomudflow,nosnowbiomes,noflat,notrees
 
 #    Controls size of deserts and beaches in Mapgen v6.
 #    When snowbiomes are enabled 'mgv6_freq_desert' is ignored.
diff --git a/minetest.conf.example b/minetest.conf.example
index 39f80bf68..d8534a0f5 100644
--- a/minetest.conf.example
+++ b/minetest.conf.example
@@ -1021,11 +1021,12 @@
 # map_generation_limit = 31000
 
 #    Global map generation attributes.
-#    The 'trees' flag only has effect in mgv6.
+#    In Mapgen v6 the 'decorations' flag controls all decorations except trees
+#    and junglegrass, in all other mapgens this flag controls all decorations.
 #    Flags that are not specified in the flag string are not modified from the default.
 #    Flags starting with "no" are used to explicitly disable them.
-#    type: flags possible values: trees, caves, dungeons, light, notrees, nocaves, nodungeons, nolight
-# mg_flags = trees,caves,dungeons,light
+#    type: flags possible values: caves, dungeons, light, decorations, nocaves, nodungeons, nolight, nodecorations
+# mg_flags = caves,dungeons,light,decorations
 
 ### Advanced
 
@@ -1093,8 +1094,8 @@
 #    When snowbiomes are enabled jungles are enabled and the jungles flag is ignored.
 #    Flags that are not specified in the flag string are not modified from the default.
 #    Flags starting with "no" are used to explicitly disable them.
-#    type: flags possible values: jungles, biomeblend, mudflow, snowbiomes, flat, nojungles, nobiomeblend, nomudflow, nosnowbiomes, noflat
-# mgv6_spflags = jungles,biomeblend,mudflow,snowbiomes
+#    type: flags possible values: jungles, biomeblend, mudflow, snowbiomes, flat, trees, nojungles, nobiomeblend, nomudflow, nosnowbiomes, noflat, notrees
+# mgv6_spflags = jungles,biomeblend,mudflow,snowbiomes,trees
 
 #    Controls size of deserts and beaches in Mapgen v6.
 #    When snowbiomes are enabled 'mgv6_freq_desert' is ignored.
diff --git a/src/defaultsettings.cpp b/src/defaultsettings.cpp
index 3315f4aaa..42eddb8ce 100644
--- a/src/defaultsettings.cpp
+++ b/src/defaultsettings.cpp
@@ -313,7 +313,7 @@ void set_default_settings(Settings *settings)
 	settings->setDefault("water_level", "1");
 	settings->setDefault("chunksize", "5");
 	settings->setDefault("mg_flags", "dungeons");
-	settings->setDefault("mgv6_spflags", "jungles, snowbiomes");
+	settings->setDefault("mgv6_spflags", "jungles, snowbiomes, trees");
 
 	// IPv6
 	settings->setDefault("enable_ipv6", "true");
diff --git a/src/mapgen.cpp b/src/mapgen.cpp
index 8a77000fa..5a209eddd 100644
--- a/src/mapgen.cpp
+++ b/src/mapgen.cpp
@@ -41,11 +41,12 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 #include "log.h"
 
 FlagDesc flagdesc_mapgen[] = {
-	{"trees",    MG_TREES},
-	{"caves",    MG_CAVES},
-	{"dungeons", MG_DUNGEONS},
-	{"flat",     MG_FLAT},
-	{"light",    MG_LIGHT},
+	{"trees",       MG_TREES},
+	{"caves",       MG_CAVES},
+	{"dungeons",    MG_DUNGEONS},
+	{"flat",        MG_FLAT},
+	{"light",       MG_LIGHT},
+	{"decorations", MG_DECORATIONS},
 	{NULL,       0}
 };
 
diff --git a/src/mapgen.h b/src/mapgen.h
index 57e995847..31cf7dc11 100644
--- a/src/mapgen.h
+++ b/src/mapgen.h
@@ -29,11 +29,12 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 #define DEFAULT_MAPGEN "v6"
 
 /////////////////// Mapgen flags
-#define MG_TREES         0x01
-#define MG_CAVES         0x02
-#define MG_DUNGEONS      0x04
-#define MG_FLAT          0x08
-#define MG_LIGHT         0x10
+#define MG_TREES       0x01
+#define MG_CAVES       0x02
+#define MG_DUNGEONS    0x04
+#define MG_FLAT        0x08
+#define MG_LIGHT       0x10
+#define MG_DECORATIONS 0x20
 
 class Settings;
 class MMVManip;
@@ -126,7 +127,7 @@ struct MapgenParams {
 		chunksize(5),
 		seed(0),
 		water_level(1),
-		flags(MG_TREES | MG_CAVES | MG_LIGHT),
+		flags(MG_CAVES | MG_LIGHT | MG_DECORATIONS),
 		np_biome_heat(NoiseParams(50, 50, v3f(750.0, 750.0, 750.0), 5349, 3, 0.5, 2.0)),
 		np_biome_heat_blend(NoiseParams(0, 1.5, v3f(8.0, 8.0, 8.0), 13, 2, 1.0, 2.0)),
 		np_biome_humidity(NoiseParams(50, 50, v3f(750.0, 750.0, 750.0), 842, 3, 0.5, 2.0)),
diff --git a/src/mapgen_flat.cpp b/src/mapgen_flat.cpp
index 7a8fe18a6..1b41d0acf 100644
--- a/src/mapgen_flat.cpp
+++ b/src/mapgen_flat.cpp
@@ -296,7 +296,8 @@ void MapgenFlat::makeChunk(BlockMakeData *data)
 	}
 
 	// Generate the registered decorations
-	m_emerge->decomgr->placeAllDecos(this, blockseed, node_min, node_max);
+	if (flags & MG_DECORATIONS)
+		m_emerge->decomgr->placeAllDecos(this, blockseed, node_min, node_max);
 
 	// Generate the registered ores
 	m_emerge->oremgr->placeAllOres(this, blockseed, node_min, node_max);
diff --git a/src/mapgen_fractal.cpp b/src/mapgen_fractal.cpp
index 89d4e53d3..26ebec353 100644
--- a/src/mapgen_fractal.cpp
+++ b/src/mapgen_fractal.cpp
@@ -310,7 +310,8 @@ void MapgenFractal::makeChunk(BlockMakeData *data)
 	}
 
 	// Generate the registered decorations
-	m_emerge->decomgr->placeAllDecos(this, blockseed, node_min, node_max);
+	if (flags & MG_DECORATIONS)
+		m_emerge->decomgr->placeAllDecos(this, blockseed, node_min, node_max);
 
 	// Generate the registered ores
 	m_emerge->oremgr->placeAllOres(this, blockseed, node_min, node_max);
diff --git a/src/mapgen_v5.cpp b/src/mapgen_v5.cpp
index 10e9f5e65..3d7e3bf83 100644
--- a/src/mapgen_v5.cpp
+++ b/src/mapgen_v5.cpp
@@ -296,7 +296,8 @@ void MapgenV5::makeChunk(BlockMakeData *data)
 	}
 
 	// Generate the registered decorations
-	m_emerge->decomgr->placeAllDecos(this, blockseed, node_min, node_max);
+	if (flags & MG_DECORATIONS)
+		m_emerge->decomgr->placeAllDecos(this, blockseed, node_min, node_max);
 
 	// Generate the registered ores
 	m_emerge->oremgr->placeAllOres(this, blockseed, node_min, node_max);
diff --git a/src/mapgen_v6.cpp b/src/mapgen_v6.cpp
index 3f3ccba4f..3b5915bd1 100644
--- a/src/mapgen_v6.cpp
+++ b/src/mapgen_v6.cpp
@@ -43,6 +43,7 @@ FlagDesc flagdesc_mapgen_v6[] = {
 	{"mudflow",    MGV6_MUDFLOW},
 	{"snowbiomes", MGV6_SNOWBIOMES},
 	{"flat",       MGV6_FLAT},
+	{"trees",      MGV6_TREES},
 	{NULL,         0}
 };
 
@@ -580,11 +581,12 @@ void MapgenV6::makeChunk(BlockMakeData *data)
 	growGrass();
 
 	// Generate some trees, and add grass, if a jungle
-	if (flags & MG_TREES)
+	if ((spflags & MGV6_TREES) || (flags & MG_TREES))
 		placeTreesAndJungleGrass();
 
 	// Generate the registered decorations
-	m_emerge->decomgr->placeAllDecos(this, blockseed, node_min, node_max);
+	if (flags & MG_DECORATIONS)
+		m_emerge->decomgr->placeAllDecos(this, blockseed, node_min, node_max);
 
 	// Generate the registered ores
 	m_emerge->oremgr->placeAllOres(this, blockseed, node_min, node_max);
diff --git a/src/mapgen_v6.h b/src/mapgen_v6.h
index dec92ab48..612e2322a 100644
--- a/src/mapgen_v6.h
+++ b/src/mapgen_v6.h
@@ -37,6 +37,7 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 #define MGV6_MUDFLOW    0x04
 #define MGV6_SNOWBIOMES 0x08
 #define MGV6_FLAT       0x10
+#define MGV6_TREES      0x20
 
 
 extern FlagDesc flagdesc_mapgen_v6[];
diff --git a/src/mapgen_v7.cpp b/src/mapgen_v7.cpp
index 77b9721c7..679d860dc 100644
--- a/src/mapgen_v7.cpp
+++ b/src/mapgen_v7.cpp
@@ -317,7 +317,8 @@ void MapgenV7::makeChunk(BlockMakeData *data)
 	}
 
 	// Generate the registered decorations
-	m_emerge->decomgr->placeAllDecos(this, blockseed, node_min, node_max);
+	if (flags & MG_DECORATIONS)
+		m_emerge->decomgr->placeAllDecos(this, blockseed, node_min, node_max);
 
 	// Generate the registered ores
 	m_emerge->oremgr->placeAllOres(this, blockseed, node_min, node_max);