From 3af226cb0644e0a9b93a6892642470a308367da0 Mon Sep 17 00:00:00 2001
From: sfan5 <sfan5@live.de>
Date: Fri, 6 Sep 2024 11:30:10 +0200
Subject: [PATCH] Refactor "Cavegen y biome check"
---
src/mapgen/cavegen.cpp | 16 +++++-----------
src/mapgen/mapgen.cpp | 15 ++-------------
src/mapgen/mg_biome.cpp | 35 ++++++++++++-----------------------
src/mapgen/mg_biome.h | 14 ++++++++++----
4 files changed, 29 insertions(+), 51 deletions(-)
diff --git a/src/mapgen/cavegen.cpp b/src/mapgen/cavegen.cpp
index 47272142f..e6ab66980 100644
--- a/src/mapgen/cavegen.cpp
+++ b/src/mapgen/cavegen.cpp
@@ -82,8 +82,6 @@ void CavesNoiseIntersection::generateCaves(MMVManip *vm,
const v3s16 &em = vm->m_area.getExtent();
u32 index2d = 0; // Biomemap index
- s16 *biome_transitions = m_bmgn->getBiomeTransitions();
-
for (s16 z = nmin.Z; z <= nmax.Z; z++)
for (s16 x = nmin.X; x <= nmax.X; x++, index2d++) {
bool column_is_open = false; // Is column open to overground
@@ -101,8 +99,7 @@ void CavesNoiseIntersection::generateCaves(MMVManip *vm,
u16 depth_riverbed = biome->depth_riverbed;
u16 nplaced = 0;
- int cur_biome_depth = 0;
- s16 biome_y_min = biome_transitions[cur_biome_depth];
+ s16 biome_y_min = m_bmgn->getNextTransitionY(nmax.Y);
// Don't excavate the overgenerated stone at nmax.Y + 1,
// this creates a 'roof' over the tunnel, preventing light in
@@ -114,15 +111,12 @@ void CavesNoiseIntersection::generateCaves(MMVManip *vm,
// We need this check to make sure that biomes don't generate too far down
if (y < biome_y_min) {
biome = m_bmgn->getBiomeAtIndex(index2d, v3s16(x, y, z));
+ biome_y_min = m_bmgn->getNextTransitionY(y);
- // Finding the height of the next biome
- // On first iteration this may loop a couple times after than it should just run once
- while (y < biome_y_min) {
- biome_y_min = biome_transitions[++cur_biome_depth];
+ if (x == nmin.X && z == nmin.Z && false) {
+ dstream << "cavegen: biome at " << y << " is " << biome->name
+ << ", next at " << biome_y_min << std::endl;
}
-
- /*if (x == nmin.X && z == nmin.Z)
- printf("Cave: check @ %i -> %s -> again at %i\n", y, biome->name.c_str(), biome_y_min);*/
}
content_t c = vm->m_data[vi].getContent();
diff --git a/src/mapgen/mapgen.cpp b/src/mapgen/mapgen.cpp
index 80ffebc9e..0b821e02e 100644
--- a/src/mapgen/mapgen.cpp
+++ b/src/mapgen/mapgen.cpp
@@ -649,8 +649,6 @@ void MapgenBasic::generateBiomes()
noise_filler_depth->perlinMap2D(node_min.X, node_min.Z);
- s16 *biome_transitions = biomegen->getBiomeTransitions();
-
for (s16 z = node_min.Z; z <= node_max.Z; z++)
for (s16 x = node_min.X; x <= node_max.X; x++, index++) {
Biome *biome = NULL;
@@ -661,8 +659,7 @@ void MapgenBasic::generateBiomes()
u16 depth_riverbed = 0;
u32 vi = vm->m_area.index(x, node_max.Y, z);
- int cur_biome_depth = 0;
- s16 biome_y_min = biome_transitions[cur_biome_depth];
+ s16 biome_y_min = biomegen->getNextTransitionY(node_max.Y);
// Check node at base of mapchunk above, either a node of a previously
// generated mapchunk or if not, a node of overgenerated base terrain.
@@ -695,15 +692,7 @@ void MapgenBasic::generateBiomes()
if (!biome || y < biome_y_min) {
// (Re)calculate biome
biome = biomegen->getBiomeAtIndex(index, v3s16(x, y, z));
-
- // Finding the height of the next biome
- // On first iteration this may loop a couple times after than it should just run once
- while (y < biome_y_min) {
- biome_y_min = biome_transitions[++cur_biome_depth];
- }
-
- /*if (x == node_min.X && z == node_min.Z)
- printf("Map: check @ %i -> %s -> again at %i\n", y, biome->name.c_str(), biome_y_min);*/
+ biome_y_min = biomegen->getNextTransitionY(y);
}
// Add biome to biomemap at first stone surface detected
diff --git a/src/mapgen/mg_biome.cpp b/src/mapgen/mg_biome.cpp
index 83ecbd691..b270a5413 100644
--- a/src/mapgen/mg_biome.cpp
+++ b/src/mapgen/mg_biome.cpp
@@ -149,47 +149,36 @@ BiomeGenOriginal::BiomeGenOriginal(BiomeManager *biomemgr,
// is disabled.
memset(biomemap, 0, sizeof(biome_t) * m_csize.X * m_csize.Z);
- // Calculating the bounding position of each biome so we know when we might switch
- // First gathering all heights where we might switch
- std::vector<s16> temp_transition_heights;
- temp_transition_heights.reserve(m_bmgr->getNumObjects() * 2);
+ // Calculate cache of Y transition points
+ std::vector<s16> values;
+ values.reserve(m_bmgr->getNumObjects() * 2);
for (size_t i = 0; i < m_bmgr->getNumObjects(); i++) {
Biome *b = (Biome *)m_bmgr->getRaw(i);
- temp_transition_heights.push_back(b->max_pos.Y);
- temp_transition_heights.push_back(b->min_pos.Y);
+ values.push_back(b->max_pos.Y);
+ values.push_back(b->min_pos.Y);
}
- // Sorting the biome transition points
- std::sort(temp_transition_heights.begin(), temp_transition_heights.end(), std::greater<int>());
+ std::sort(values.begin(), values.end(), std::greater<>());
+ values.erase(std::unique(values.begin(), values.end()), values.end());
- // Getting rid of duplicate biome transition points
- s16 last = temp_transition_heights[0];
- size_t out_pos = 1;
- for (size_t i = 1; i < temp_transition_heights.size(); i++){
- if (temp_transition_heights[i] != last) {
- last = temp_transition_heights[i];
- temp_transition_heights[out_pos++] = last;
- }
- }
-
- biome_transitions = new s16[out_pos];
- memcpy(biome_transitions, temp_transition_heights.data(), sizeof(s16) * out_pos);
+ m_transitions_y = std::move(values);
}
BiomeGenOriginal::~BiomeGenOriginal()
{
delete []biomemap;
- delete []biome_transitions;
delete noise_heat;
delete noise_humidity;
delete noise_heat_blend;
delete noise_humidity_blend;
}
-s16* BiomeGenOriginal::getBiomeTransitions() const
+s16 BiomeGenOriginal::getNextTransitionY(s16 y) const
{
- return biome_transitions;
+ // Find first value that is less than y using binary search
+ auto it = std::lower_bound(m_transitions_y.begin(), m_transitions_y.end(), y, std::greater_equal<>());
+ return (it == m_transitions_y.end()) ? S16_MIN : *it;
}
BiomeGen *BiomeGenOriginal::clone(BiomeManager *biomemgr) const
diff --git a/src/mapgen/mg_biome.h b/src/mapgen/mg_biome.h
index 567a0fe81..389b36ee9 100644
--- a/src/mapgen/mg_biome.h
+++ b/src/mapgen/mg_biome.h
@@ -128,11 +128,14 @@ public:
// Same as above, but uses a raw numeric index correlating to the (x,z) position.
virtual Biome *getBiomeAtIndex(size_t index, v3s16 pos) const = 0;
- virtual s16 *getBiomeTransitions() const = 0;
+ // Returns the next lower y position at which the biome could change.
+ // You can use this to optimize calls to getBiomeAtIndex().
+ virtual s16 getNextTransitionY(s16 y) const {
+ return y == S16_MIN ? y : (y - 1);
+ };
// Result of calcBiomes bulk computation.
biome_t *biomemap = nullptr;
- s16 *biome_transitions = nullptr;
protected:
BiomeManager *m_bmgr = nullptr;
@@ -167,7 +170,7 @@ struct BiomeParamsOriginal : public BiomeParams {
NoiseParams np_humidity_blend;
};
-class BiomeGenOriginal : public BiomeGen {
+class BiomeGenOriginal final : public BiomeGen {
public:
BiomeGenOriginal(BiomeManager *biomemgr,
const BiomeParamsOriginal *params, v3s16 chunksize);
@@ -189,7 +192,7 @@ public:
Biome *getBiomeAtIndex(size_t index, v3s16 pos) const;
Biome *calcBiomeFromNoise(float heat, float humidity, v3s16 pos) const;
- s16 *getBiomeTransitions() const;
+ s16 getNextTransitionY(s16 y) const;
float *heatmap;
float *humidmap;
@@ -201,6 +204,9 @@ private:
Noise *noise_humidity;
Noise *noise_heat_blend;
Noise *noise_humidity_blend;
+
+ // ordered descending
+ std::vector<s16> m_transitions_y;
};