New math mapgen with fractal based worlds

minetest.conf.example

@@ -325,7 +325,7 @@
 # Mapgen stuff
 #
 
-# Name of map generator to be used.  Currently v6, indev and singlenode are supported.
+# Name of map generator to be used.  Currently supported: v6, indev, singlenode, math
 #mg_name = v6
 # Water level of map.
 #water_level = 1
@@ -368,6 +368,9 @@
 # Float islands starts from height, 0 to disable
 #mgindev_float_islands = 500
 
+# Math mapgen generator: sphere, mandelbox, mengersponge      dont forget to lower water_level = -30000
+#mgmath_generator = mandelbox
+
 # Enable/disable IPv6
 #enable_ipv6 = true
 # Enable/disable running an IPv6 server.  An IPv6 server may be restricted

src/CMakeLists.txt

@@ -233,6 +233,7 @@ set(common_SRCS
 	mapgen_v7.cpp
 	mapgen_indev.cpp
 	mapgen_singlenode.cpp
+	mapgen_math.cpp
 	treegen.cpp
 	dungeongen.cpp
 	cavegen.cpp

src/defaultsettings.cpp

@@ -252,6 +252,8 @@ void set_default_settings(Settings *settings)
 	settings->setDefault("mgindev_np_biome",          "0,    1,   (250, 250, 250), 9130,  3, 0.50, 1,   10");
 	settings->setDefault("mgindev_float_islands", "500");
 
+	settings->setDefault("mgmath_generator", "mandelbox");
+
 	// IPv6
 	settings->setDefault("enable_ipv6", "true");
 	settings->setDefault("ipv6_server", "false");

src/emerge.cpp

@@ -42,6 +42,7 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 #include "mapgen_v7.h"
 #include "mapgen_indev.h"
 #include "mapgen_singlenode.h"
+#include "mapgen_math.h"
 
 
 /////////////////////////////// Emerge Manager ////////////////////////////////
@@ -52,6 +53,7 @@ EmergeManager::EmergeManager(IGameDef *gamedef) {
 	registerMapgen("v7", new MapgenFactoryV7());
 	registerMapgen("indev", new MapgenFactoryIndev());
 	registerMapgen("singlenode", new MapgenFactorySinglenode());
+	registerMapgen("math", new MapgenFactoryMath());
 
 	this->ndef     = gamedef->getNodeDefManager();
 	this->biomedef = new BiomeDefManager();

src/mapgen_math.cpp

@@ -0,0 +1,366 @@
+/*
+Minetest
+Copyright (C) 2010-2013 celeron55, Perttu Ahola <celeron55@gmail.com>
+
+This program 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 program 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 program; if not, write to the Free Software Foundation, Inc.,
+51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+*/
+
+#include <cmath>
+#include "mapgen_math.h"
+#include "voxel.h"
+#include "mapblock.h"
+#include "mapnode.h"
+#include "map.h"
+#include "nodedef.h"
+#include "voxelalgorithms.h"
+#include "profiler.h"
+#include "settings.h" // For g_settings
+#include "main.h" // For g_profiler
+#include "emerge.h"
+#include "biome.h"
+
+// can use ported lib from http://mandelbulber.googlecode.com/svn/trunk/src
+//#include "mandelbulber/fractal.h"
+//#include "mandelbulber/fractal.cpp"
+
+double mandelbox(double x, double y, double z, double d, int nn = 10) {
+	int s = 7;
+	x *= s;
+	y *= s;
+	z *= s;
+	d *= s;
+
+	double posX = x;
+	double posY = y;
+	double posZ = z;
+
+	double dr = 1.0;
+	double r = 0.0;
+
+	double scale = 2;
+
+	double minRadius2 = 0.25;
+	double fixedRadius2 = 1;
+
+	for (int n = 0; n < nn; n++) {
+		// Reflect
+		if (x > 1.0)
+			x = 2.0 - x;
+		else if (x < -1.0)
+			x = -2.0 - x;
+		if (y > 1.0)
+			y = 2.0 - y;
+		else if (y < -1.0)
+			y = -2.0 - y;
+		if (z > 1.0)
+			z = 2.0 - z;
+		else if (z < -1.0)
+			z = -2.0 - z;
+
+		// Sphere Inversion
+		double r2 = x * x + y * y + z * z;
+
+		if (r2 < minRadius2) {
+			x = x * fixedRadius2 / minRadius2;
+			y = y * fixedRadius2 / minRadius2;
+			z = z * fixedRadius2 / minRadius2;
+			dr = dr * fixedRadius2 / minRadius2;
+		} else if (r2 < fixedRadius2) {
+			x = x * fixedRadius2 / r2;
+			y = y * fixedRadius2 / r2;
+			z = z * fixedRadius2 / r2;
+			fixedRadius2 *= fixedRadius2 / r2;
+		}
+
+		x = x * scale + posX;
+		y = y * scale + posY;
+		z = z * scale + posZ;
+		dr *= scale;
+	}
+	r = sqrt(x * x + y * y + z * z);
+	return ((r / fabs(dr)) < d);
+
+}
+
+double mengersponge(double x, double y, double z, double d, int MI = 10) {
+
+	double r = x * x + y * y + z * z;
+	double scale = 3;
+	int i = 0;
+
+
+	for (i = 0; i < MI && r < 9; i++) {
+
+
+		x = fabs(x);
+		y = fabs(y);
+		z = fabs(z);
+
+
+		if (x - y < 0) {
+			double x1 = y;
+			y = x;
+			x = x1;
+		}
+		if (x - z < 0) {
+			double x1 = z;
+			z = x;
+			x = x1;
+		}
+		if (y - z < 0) {
+			double y1 = z;
+			z = y;
+			y = y1;
+		}
+
+
+		x = scale * x - 1 * (scale - 1);
+		y = scale * y - 1 * (scale - 1);
+		z = scale * z;
+
+
+		if (z > 0.5 * 1 * (scale - 1))
+			z -= 1 * (scale - 1);
+
+
+		r = x * x + y * y + z * z;
+	}
+	return ((sqrt(r)) * pow(scale, (-i)) < d);
+}
+
+double sphere(double x, double y, double z, double d, int ITR = 1) {
+	return v3f(x, y, z).getLength() < d;
+}
+
+
+//////////////////////// Mapgen Singlenode parameter read/write
+
+bool MapgenMathParams::readParams(Settings *settings) {
+	//params = settings->getJson("mg_math");
+	// can be counfigured from here.
+	std::string value = "{}";
+	Json::Reader reader;
+	if (!reader.parse( value, params ) ) {
+		errorstream  << "Failed to parse json conf var ='" << value << "' : " << reader.getFormattedErrorMessages();
+	}
+
+	if (params["generator"].empty()) params["generator"] = settings->get("mgmath_generator");
+
+	return true;
+}
+
+
+void MapgenMathParams::writeParams(Settings *settings) {
+	//settings->setJson("mg_math", params);
+	settings->set("mgmath_generator", params["generator"].asString());
+}
+
+///////////////////////////////////////////////////////////////////////////////
+
+MapgenMath::MapgenMath(int mapgenid, MapgenMathParams *params_, EmergeManager *emerge) : MapgenV7(mapgenid, params_, emerge) {
+	mg_params = params_;
+
+	Json::Value & params = mg_params->params;
+	invert = params["invert"].empty() ? 1 : params["invert"].asBool(); //params["invert"].empty()?1:params["invert"].asBool();
+	size = params["size"].empty() ? 0 : params["size"].asDouble(); // = max_r
+	scale = params["scale"].empty() ? 0 : params["scale"].asDouble(); //(double)1 / size;
+	if(!params["center"].empty()) center = v3f(params["center"]["x"].asFloat(), params["center"]["y"].asFloat(), params["center"]["z"].asFloat()); //v3f(5, -size - 5, 5);
+	iterations = params["iterations"].empty() ? 0 : params["iterations"].asInt(); //10;
+	distance = params["distance"].empty() ? 0 : params["distance"].asDouble(); // = 1/size;
+
+	func = &sphere;
+
+	if (params["generator"].empty()) params["generator"] = "mandelbox";
+	if (params["generator"].asString() == "mengersponge") {
+		if (!size) size = (MAP_GENERATION_LIMIT - 1000) / 2;
+		if (!iterations) iterations = 10;
+		if (!distance) distance = 0.0003;
+		//if (!scale) scale = (double)0.1 / size;
+		//if (!distance) distance = 0.01; //10/size;//sqrt3 * bd4;
+		//if (!scale) scale = 0.01; //10/size;//sqrt3 * bd4;
+		//center=v3f(-size/3,-size/3+(-2*-invert),2);
+		center = v3f(-size, -size, -size);
+		func = &mengersponge;
+	} else if (params["generator"].asString() == "mandelbox") {
+		/*
+			size = MAP_GENERATION_LIMIT - 1000;
+			//size = 1000;
+			distance = 0.01; //100/size; //0.01;
+			iterations = 10;
+			center = v3f(1, 1, 1); // *size/6;
+		*/
+
+		//mandelbox
+		if (!size) size = 1000;
+		if (!distance) distance = 0.01;
+		if(params["invert"].empty()) invert = 0;
+		//center=v3f(2,-size/4,2);
+		//size = 10000;
+		//center=v3f(size/2,-size*0.9,size/2);
+		if(params["center"].empty())center = v3f(size * 0.3, -size * 0.6, size * 0.5);
+		func = &mandelbox;
+	} else if (params["generator"].asString() == "sphere") {
+		if(params["invert"].empty()) invert = 0;
+		if (!size) size = 100;
+		if (!distance) distance = size;
+		func = &sphere;
+		if (!scale) scale = 1;
+		//sphere
+		//size = 1000;scale = 1;center = v3f(2,-size-2,2);
+	}
+
+	if (!iterations) iterations = 10;
+	if (!size) size = 1000;
+	if (!scale) scale = (double)1 / size;
+	if (!distance)  distance = scale;
+	if (params["center"].empty() && !center.getLength()) center = v3f(3, -size + (-5 - (-invert * 10)), 3);
+	//size ||= params["size"].empty()?1000:params["size"].asDouble(); // = max_r
+
+}
+
+
+MapgenMath::~MapgenMath() {
+}
+
+//////////////////////// Map generator
+
+void MapgenMath::generateTerrain() {
+
+	MapNode n_air(CONTENT_AIR), n_water_source(c_water_source, LIGHT_SUN);
+	MapNode n_stone(c_stone, LIGHT_SUN);
+	u32 index = 0;
+	v3s16 em = vm->m_area.getExtent();
+
+#if 1
+
+	/* debug
+	v3f vec0 = (v3f(node_min.X, node_min.Y, node_min.Z) - center) * scale ;
+	errorstream << " X=" << node_min.X << " Y=" << node_min.Y << " Z=" << node_min.Z
+	            //<< " N="<< mengersponge(vec0.X, vec0.Y, vec0.Z, distance, iterations)
+	            << " N=" << (*func)(vec0.X, vec0.Y, vec0.Z, distance, iterations)
+	            << " Sc=" << scale << " gen=" << params["generator"].asString() << " J=" << Json::FastWriter().write(params) << std::endl;
+	*/
+	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 = bmgr->biomes[biomemap[index]];
+			u32 i = vm->m_area.index(x, node_min.Y, z);
+			for (s16 y = node_min.Y; y <= node_max.Y; y++) {
+				v3f vec = (v3f(x, y, z) - center) * scale ;
+				double d = (*func)(vec.X, vec.Y, vec.Z, distance, iterations);
+				if ((!invert && d > 0) || (invert && d == 0)  ) {
+					if (vm->m_data[i].getContent() == CONTENT_IGNORE)
+						vm->m_data[i] = (y > water_level + biome->filler_height) ?
+						                MapNode(biome->c_filler) : n_stone;
+				} else if (y <= water_level) {
+					vm->m_data[i] = n_water_source;
+				} else {
+					vm->m_data[i] = n_air;
+				}
+				vm->m_area.add_y(em, i, 1);
+			}
+		}
+	}
+#endif
+
+
+#if 0
+// mandelbulber, unfinished but works
+	sFractal par;
+	par.doubles.N = 10;
+
+	par.doubles.power = 9.0;
+	par.doubles.foldingSphericalFixed =  1.0;
+	par.doubles.foldingSphericalMin = 0.5;
+	//no par.formula = smoothMandelbox; par.doubles.N = 40; invert = 0;//no
+	par.mandelbox.doubles.sharpness = 3.0;
+	par.mandelbox.doubles.scale = 1;
+	par.mandelbox.doubles.sharpness = 2;
+	par.mandelbox.doubles.foldingLimit = 1.0;
+	par.mandelbox.doubles.foldingValue = 2;
+
+//ok	par.formula = mandelboxVaryScale4D; par.doubles.N = 50; scale = 5; invert = 1; //ok
+	par.mandelbox.doubles.vary4D.scaleVary =  0.1;
+	par.mandelbox.doubles.vary4D.fold = 1;
+	par.mandelbox.doubles.vary4D.rPower = 1;
+	par.mandelbox.doubles.vary4D.minR = 0.5;
+	par.mandelbox.doubles.vary4D.wadd = 0;
+	par.doubles.constantFactor = 1.0;
+
+	par.formula = menger_sponge; par.doubles.N = 15; invert = 0; size = 30000; center = v3f(-size / 2, -size + (-2 * -invert), 2);  scale = (double)1 / size; //ok
+
+	//double tresh = 1.5;
+	//par.formula = mandelbulb2; par.doubles.N = 10; scale = (double)1/size; invert=1; center = v3f(5,-size-5,0); //ok
+	//par.formula = hypercomplex; par.doubles.N = 20; scale = 0.0001; invert=1; center = v3f(0,-10001,0); //(double)50 / max_r;
+
+	//no par.formula = trig_DE; par.doubles.N = 5;  scale = (double)10; invert=1;
+
+	//no par.formula = trig_optim; scale = (double)10;  par.doubles.N = 4;
+
+	//par.formula = mandelbulb2; scale = (double)1/10000; par.doubles.N = 10; invert = 1; center = v3f(1,-4201,1); //ok
+	// no par.formula = tglad;
+
+	//par.formula = xenodreambuie;  par.juliaMode = 1; par.doubles.julia.x = -1; par.doubles.power = 2.0; center=v3f(-size/2,-size/2-5,5); //ok
+
+	par.mandelbox.doubles.vary4D.scaleVary = 0.1;
+	par.mandelbox.doubles.vary4D.fold = 1;
+	par.mandelbox.doubles.vary4D.minR = 0.5;
+	par.mandelbox.doubles.vary4D.rPower = 1;
+	par.mandelbox.doubles.vary4D.wadd = 0;
+	//no par.formula = mandelboxVaryScale4D;
+	par.doubles.cadd = -1.3;
+	//par.formula = aexion; // ok but center
+	//par.formula = benesi; par.doubles.N = 10; center = v3f(0,0,0); invert = 0; //ok
+
+	// par.formula = bristorbrot; //ok
+
+	v3f vec0(node_min.X, node_min.Y, node_min.Z);
+	vec0 = (vec0 - center) * scale ;
+	errorstream << " X=" << node_min.X << " Y=" << node_min.Y << " Z=" << node_min.Z
+	            << " N=" << Compute<normal>(CVector3(vec0.X, vec0.Y, vec0.Z), par)
+	            //<<" F="<< Compute<fake_AO>(CVector3(node_min.X,node_min.Y,node_min.Z), par)
+	            //<<" L="<<node_min.getLength()<< " -="<<node_min.getLength() - Compute<normal>(CVector3(node_min.X,node_min.Y,node_min.Z), par)
+	            << " Sc=" << scale
+	            << std::endl;
+
+	for (s16 z = node_min.Z; z <= node_max.Z; z++)
+		for (s16 y = node_min.Y; y <= node_max.Y; y++) {
+			u32 i = vm->m_area.index(node_min.X, y, z);
+			for (s16 x = node_min.X; x <= node_max.X; x++) {
+				v3f vec(x, y, z);
+				vec = (vec - center) * scale ;
+				//double d = Compute<fake_AO>(CVector3(x,y,z), par);
+				double d = Compute<normal>(CVector3(vec.X, vec.Y, vec.Z), par);
+				//if (d>0)
+				// errorstream << " d=" << d  <<" v="<< vec.getLength()<< " -="<< vec.getLength() - d <<" yad="
+				//<< Compute<normal>(CVector3(x,y,z), par)
+				//<< std::endl;
+				if ((!invert && d > 0) || (invert && d == 0)/*&& vec.getLength() - d > tresh*/ ) {
+					if (vm->m_data[i].getContent() == CONTENT_IGNORE)
+						vm->m_data[i] = n_stone;
+				} else {
+					vm->m_data[i] = n_air;
+				}
+				i++;
+			}
+		}
+
+
+#endif
+
+}
+
+int MapgenMath::getGroundLevelAtPoint(v2s16 p) {
+	return 0;
+}

src/mapgen_math.h

@@ -0,0 +1,70 @@
+/*
+Minetest
+Copyright (C) 2010-2013 celeron55, Perttu Ahola <celeron55@gmail.com>
+
+This program 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 program 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 program; if not, write to the Free Software Foundation, Inc.,
+51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+*/
+
+#ifndef MAPGEN_MATH_HEADER
+#define MAPGEN_MATH_HEADER
+
+#include "mapgen.h"
+#include "mapgen_v7.h"
+#include "json/json.h"
+
+struct MapgenMathParams : public MapgenV7Params {
+
+	MapgenMathParams() {
+	}
+
+	Json::Value params;
+
+	bool readParams(Settings *settings);
+	void writeParams(Settings *settings);
+};
+
+class MapgenMath : public MapgenV7 {
+	public:
+		MapgenMathParams * mg_params;
+
+		MapgenMath(int mapgenid, MapgenMathParams *mg_params, EmergeManager *emerge);
+		~MapgenMath();
+
+
+		//void makeChunk(BlockMakeData *data);
+		void generateTerrain();
+		int getGroundLevelAtPoint(v2s16 p);
+
+		bool invert;
+		double size;
+		double scale;
+		v3f center;
+		int iterations;
+		double distance;
+		double (*func)(double, double, double, double, int);
+
+};
+
+struct MapgenFactoryMath : public MapgenFactory {
+	Mapgen *createMapgen(int mgid, MapgenParams *params, EmergeManager *emerge) {
+		return new MapgenMath(mgid, (MapgenMathParams *)params, emerge);
+	};
+
+	MapgenParams *createMapgenParams() {
+		return new MapgenMathParams();
+	};
+};
+
+#endif

src/mapgen_v7.h

@@ -94,7 +94,7 @@ public:
 	MapgenV7(int mapgenid, MapgenV7Params *params, EmergeManager *emerge);
 	~MapgenV7();
 	
-	void makeChunk(BlockMakeData *data);
+	virtual void makeChunk(BlockMakeData *data);
 	int getGroundLevelAtPoint(v2s16 p);
 	Biome *getBiomeAtPoint(v3s16 p);
 
@@ -103,7 +103,7 @@ public:
 	void calculateNoise();
 	int calcHeightMap();
 	
-	void generateTerrain();
+	virtual void generateTerrain();
 	void carveRidges();
 	//void carveRivers(); //experimental