Initial commit.

README.md

@@ -0,0 +1,60 @@
+#Voronoi Biomes Patch
+
+
+##Place biomes to match their Voronoi diagram
+
+This is a patch for minetest that allows creating worlds with biomes
+arranged in the standard Voronoi pattern. Heat (or temperature) on the x-axis and humidity
+on the z-axis.
+
+![Screenshot 1](default_biomes.jpeg "Default Voronoi world")
+
+![Screenshot 2](ethereal_biomes.jpeg "Ethereal Voronoi world")
+
+**This is a proof of concept that is intended for people who are experienced compiling minetest themselves.**
+
+
+** Cautions **
+
+- Once this patch is applied, there is no way to set it back to normal functionality without reverting the patch and recompiling.
+- Therefore, make this change to a separate copy of minetest, and use the `RUN_IN_PLACE` option to keep this version's files completely separate from your regular minetest version.
+
+
+**Compile minetest with this patch**
+
+- Download minetest source code to new directory and compile regularly. I used commit dde0628976… from Oct 5, 2019.
+- Patch `src/mapgen/mg_biome.cpp` with included patch file, and recompile.  In Linux you can use something like:
+>       patch mg_biome.cpp /path/to/voronoi_biomes.patch
+
+
+**Source code options**
+
+- By default the patch creates Voronoi maps with sides of 500 nodes.
+- It maps x=-250 to heat=0 and x=+250 to heat=100. The corresponding values for humidity are mapped from z=-250 to z=+250.
+- This can be changed by updating the following value in the patched version of mg_biome.cpp before recompiling:
+>       #define W_Voronoi 500
+
+
+**Further customizations can be done in minetest.conf:**
+
+- Biomes are still blended, but this can be disabled or reduced by changing the values of `mg_biome_np_heat_blend` and `mg_biome_np_humidity_blend`.
+- To get a small world like shown in the screenshot above, I set `mapgen_limit = 300`.
+
+It's more difficult when the biomes change with elevation.
+
+- Multiple runs can be done with different base levels—carpathian and flat mapgens have easy options to do this.
+- Otherwise, use different mapgens and seeds to find what works. I've used amidst-minetest, but keep in mind that the biomes that program shows will be completely overridden.
+
+
+**License of source code:  LGPL-2.1**
+
+This library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version.
+
+This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public License along with this library; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+
+
+**License of media (images):  CC-BY-SA-4.0**
+
+This work is licensed under the Creative Commons Attribution-ShareAlike 4.0 International License. To view a copy of this license, visit http://creativecommons.org/licenses/by-sa/4.0/ or send a letter to Creative Commons, PO Box 1866, Mountain View, CA 94042, USA.

voronoi_biomes.patch

@@ -0,0 +1,74 @@
+--- mg_biome.cpp.orig	2019-09-14 09:04:44.522429758 -0700
++++ mg_biome.cpp	2019-10-06 15:31:13.478110742 -0700
+@@ -18,6 +18,10 @@
+ 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+ 
++// Modified by David G (kestral246@gmail.com)
++// 2019-10-05
++// Hack to give Voronoi biome distribution. 
++
+ #include "mg_biome.h"
+ #include "mg_decoration.h"
+ #include "emerge.h"
+@@ -31,6 +35,8 @@
+ 
+ ///////////////////////////////////////////////////////////////////////////////
+ 
++// Length of side of full Voronoi biome map, centered about (0,0)
++#define W_Voronoi 500.0
+ 
+ BiomeManager::BiomeManager(Server *server) :
+ 	ObjDefManager(server, OBJDEF_BIOME)
+@@ -97,7 +103,8 @@
+ 	NoiseParams &np_heat_blend, u64 seed)
+ {
+ 	return
+-		NoisePerlin2D(&np_heat,       pos.X, pos.Z, seed) +
++		//NoisePerlin2D(&np_heat,       pos.X, pos.Z, seed) +
++		(W_Voronoi/2 + pos.X) * 100/W_Voronoi +
+ 		NoisePerlin2D(&np_heat_blend, pos.X, pos.Z, seed);
+ }
+ 
+@@ -107,7 +114,8 @@
+ 	NoiseParams &np_humidity_blend, u64 seed)
+ {
+ 	return
+-		NoisePerlin2D(&np_humidity,       pos.X, pos.Z, seed) +
++		//NoisePerlin2D(&np_humidity,       pos.X, pos.Z, seed) +
++		(W_Voronoi/2 + pos.Z) * 100/W_Voronoi +
+ 		NoisePerlin2D(&np_humidity_blend, pos.X, pos.Z, seed);
+ }
+ 
+@@ -215,10 +223,12 @@
+ Biome *BiomeGenOriginal::calcBiomeAtPoint(v3s16 pos) const
+ {
+ 	float heat =
+-		NoisePerlin2D(&m_params->np_heat,       pos.X, pos.Z, m_params->seed) +
++		//NoisePerlin2D(&m_params->np_heat,       pos.X, pos.Z, m_params->seed) +
++		(W_Voronoi/2 + pos.X) * 100/W_Voronoi +
+ 		NoisePerlin2D(&m_params->np_heat_blend, pos.X, pos.Z, m_params->seed);
+ 	float humidity =
+-		NoisePerlin2D(&m_params->np_humidity,       pos.X, pos.Z, m_params->seed) +
++		//NoisePerlin2D(&m_params->np_humidity,       pos.X, pos.Z, m_params->seed) +
++		(W_Voronoi/2 + pos.Z) * 100/W_Voronoi +
+ 		NoisePerlin2D(&m_params->np_humidity_blend, pos.X, pos.Z, m_params->seed);
+ 
+ 	return calcBiomeFromNoise(heat, humidity, pos);
+@@ -234,6 +244,11 @@
+ 	noise_heat_blend->perlinMap2D(pmin.X, pmin.Z);
+ 	noise_humidity_blend->perlinMap2D(pmin.X, pmin.Z);
+ 
++	for (s32 i = 0; i < m_csize.X; i++)
++		for (s32 j = 0; j < m_csize.Z; j++) {
++			noise_heat->result[i + j*m_csize.X] = (W_Voronoi/2 + pmin.X + i) * 100/W_Voronoi;
++			noise_humidity->result[i + j*m_csize.X] = (W_Voronoi/2 + pmin.Z + j) * 100/W_Voronoi;
++		}
+ 	for (s32 i = 0; i < m_csize.X * m_csize.Z; i++) {
+ 		noise_heat->result[i]     += noise_heat_blend->result[i];
+ 		noise_humidity->result[i] += noise_humidity_blend->result[i];
+@@ -336,3 +351,4 @@
+ 	getIdFromNrBacklog(&c_dungeon_alt,   "ignore",                    CONTENT_IGNORE, false);
+ 	getIdFromNrBacklog(&c_dungeon_stair, "ignore",                    CONTENT_IGNORE, false);
+ }
++