From a89d2cf9c91d9490fd554198f9417bf7424051a1 Mon Sep 17 00:00:00 2001
From: Cubitect <cubitect@gmail.com>
Date: Sun, 14 Aug 2022 18:00:23 +0200
Subject: [PATCH] More expressive dimensions

---
 finders.c   |  6 +++---
 generator.c | 18 +++++++++---------
 layers.c    |  9 +++++++++
 layers.h    |  9 +++++++++
 4 files changed, 30 insertions(+), 12 deletions(-)

diff --git a/finders.c b/finders.c
index 702d537..c108494 100644
--- a/finders.c
+++ b/finders.c
@@ -1854,7 +1854,7 @@ int isViableStructurePos(int structureType, Generator *g, int x, int z, uint32_t
     int id;
 
 
-    if (g->dim == -1) // Nether
+    if (g->dim == DIM_NETHER)
     {
         if (structureType == Fortress && g->mc <= MC_1_17)
             return 1;
@@ -1893,7 +1893,7 @@ int isViableStructurePos(int structureType, Generator *g, int x, int z, uint32_t
         id = getBiomeAt(g, 4, sampleX, sampleY, sampleZ);
         return isViableFeatureBiome(g->mc, structureType, id);
     }
-    else if (g->dim == +1) // End
+    else if (g->dim == DIM_END)
     {
         switch (structureType)
         {
@@ -2978,7 +2978,7 @@ int checkForBiomes(
         return 0;
     int i, j, k, ret;
 
-    if (g->mc <= MC_1_17 && dim == 0)
+    if (g->mc <= MC_1_17 && dim == DIM_OVERWORLD)
     {
         Layer *entry = (Layer*) getLayerForScale(g, r.scale);
         ret = checkForBiomesAtLayer(&g->ls, entry, cache, seed,
diff --git a/generator.c b/generator.c
index 8893b8b..ecb9a4a 100644
--- a/generator.c
+++ b/generator.c
@@ -62,7 +62,7 @@ int mapOceanMixMod(const Layer * l, int * out, int x, int z, int w, int h)
 void setupGenerator(Generator *g, int mc, uint32_t flags)
 {
     g->mc = mc;
-    g->dim = 1000; // not initialized
+    g->dim = DIM_UNDEF;
     g->flags = flags;
     g->seed = 0;
     g->sha = 0;
@@ -98,24 +98,24 @@ void applySeed(Generator *g, int dim, uint64_t seed)
     g->seed = seed;
     g->sha = 0;
 
-    if (dim == 0)
+    if (dim == DIM_OVERWORLD)
     {
         if (g->mc <= MC_1_17)
             setLayerSeed(g->entry ? g->entry : g->ls.entry_1, seed);
         else
             setBiomeSeed(&g->bn, seed, g->flags & LARGE_BIOMES);
     }
-    else if (dim == -1 && g->mc >= MC_1_16)
+    else if (dim == DIM_NETHER && g->mc >= MC_1_16)
     {
         setNetherSeed(&g->nn, seed);
     }
-    else if (dim == +1 && g->mc >= MC_1_9)
+    else if (dim == DIM_END && g->mc >= MC_1_9)
     {
         setEndSeed(&g->en, seed);
     }
     if (g->mc >= MC_1_15)
     {
-        if (g->mc <= MC_1_17 && dim == 0 && !g->entry)
+        if (g->mc <= MC_1_17 && dim == DIM_OVERWORLD && !g->entry)
             g->sha = g->ls.entry_1->startSalt;
         else
             g->sha = getVoronoiSHA(seed);
@@ -129,7 +129,7 @@ size_t getMinCacheSize(const Generator *g, int scale, int sx, int sy, int sz)
         sy = 1;
 
     size_t len = (size_t)sx * sz * sy;
-    if (g->mc <= MC_1_17 && g->dim == 0)
+    if (g->mc <= MC_1_17 && g->dim == DIM_OVERWORLD)
     {   // recursively check the layer stack for the max buffer
         const Layer *entry = getLayerForScale(g, scale);
         if (!entry) {
@@ -161,7 +161,7 @@ int genBiomes(const Generator *g, int *cache, Range r)
     int err = 1;
     int i, k;
 
-    if (g->dim == 0)
+    if (g->dim == DIM_OVERWORLD)
     {
         if (g->mc <= MC_1_17)
         {
@@ -181,11 +181,11 @@ int genBiomes(const Generator *g, int *cache, Range r)
             return genBiomeNoiseScaled(&g->bn, cache, r, g->mc, g->sha);
         }
     }
-    else if (g->dim == -1)
+    else if (g->dim == DIM_NETHER)
     {
         return genNetherScaled(&g->nn, cache, r, g->mc, g->sha);
     }
-    else if (g->dim == +1)
+    else if (g->dim == DIM_END)
     {
         return genEndScaled(&g->en, cache, r, g->mc, g->sha);
     }
diff --git a/layers.c b/layers.c
index 24b20d0..daf707a 100644
--- a/layers.c
+++ b/layers.c
@@ -158,6 +158,15 @@ int isOverworld(int mc, int id)
     return 1;
 }
 
+int getDimension(int id)
+{
+    if (id >= small_end_islands && id <= end_barrens) return DIM_END;
+    if (id >= soul_sand_valley && id <= basalt_deltas) return DIM_NETHER;
+    if (id == the_end) return DIM_END;
+    if (id == nether_wastes) return DIM_NETHER;
+    return DIM_OVERWORLD;
+}
+
 int getMutated(int mc, int id)
 {
     switch (id)
diff --git a/layers.h b/layers.h
index 2e7424f..621b005 100644
--- a/layers.h
+++ b/layers.h
@@ -17,6 +17,14 @@ enum MCVersion
     MC_1_19, MC_NEWEST = MC_1_19,
 };
 
+enum Dimension
+{
+    DIM_NETHER      =   -1,
+    DIM_OVERWORLD   =    0,
+    DIM_END         =   +1,
+    DIM_UNDEF       = 1000,
+};
+
 enum BiomeID
 {
     none = -1,
@@ -489,6 +497,7 @@ int genBiomeNoiseScaled(const BiomeNoise *bn, int *out, Range r, int mc, uint64_
 
 int biomeExists(int mc, int id);
 int isOverworld(int mc, int id);
+int getDimension(int id);
 int getMutated(int mc, int id);
 int getCategory(int mc, int id);
 int areSimilar(int mc, int id1, int id2);