minetest/src/scriptapi_noise.cpp

/*
Minetest
Copyright (C) 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 "scriptapi.h"
#include "scriptapi_noise.h"
#include "scriptapi_types.h"
#include "script.h"

// garbage collector
int LuaPerlinNoise::gc_object(lua_State *L)
{
	LuaPerlinNoise *o = *(LuaPerlinNoise **)(lua_touserdata(L, 1));
	delete o;
	return 0;
}

int LuaPerlinNoise::l_get2d(lua_State *L)
{
	LuaPerlinNoise *o = checkobject(L, 1);
	v2f pos2d = read_v2f(L,2);
	lua_Number val = noise2d_perlin(pos2d.X/o->scale, pos2d.Y/o->scale, o->seed, o->octaves, o->persistence);
	lua_pushnumber(L, val);
	return 1;
}
int LuaPerlinNoise::l_get3d(lua_State *L)
{
	LuaPerlinNoise *o = checkobject(L, 1);
	v3f pos3d = read_v3f(L,2);
	lua_Number val = noise3d_perlin(pos3d.X/o->scale, pos3d.Y/o->scale, pos3d.Z/o->scale, o->seed, o->octaves, o->persistence);
	lua_pushnumber(L, val);
	return 1;
}


LuaPerlinNoise::LuaPerlinNoise(int a_seed, int a_octaves, float a_persistence,
		float a_scale):
	seed(a_seed),
	octaves(a_octaves),
	persistence(a_persistence),
	scale(a_scale)
{
}

LuaPerlinNoise::~LuaPerlinNoise()
{
}

// LuaPerlinNoise(seed, octaves, persistence, scale)
// Creates an LuaPerlinNoise and leaves it on top of stack
int LuaPerlinNoise::create_object(lua_State *L)
{
	int seed = luaL_checkint(L, 1);
	int octaves = luaL_checkint(L, 2);
	float persistence = luaL_checknumber(L, 3);
	float scale = luaL_checknumber(L, 4);
	LuaPerlinNoise *o = new LuaPerlinNoise(seed, octaves, persistence, scale);
	*(void **)(lua_newuserdata(L, sizeof(void *))) = o;
	luaL_getmetatable(L, className);
	lua_setmetatable(L, -2);
	return 1;
}

LuaPerlinNoise* LuaPerlinNoise::checkobject(lua_State *L, int narg)
{
	luaL_checktype(L, narg, LUA_TUSERDATA);
	void *ud = luaL_checkudata(L, narg, className);
	if(!ud) luaL_typerror(L, narg, className);
	return *(LuaPerlinNoise**)ud;  // unbox pointer
}

void LuaPerlinNoise::Register(lua_State *L)
{
	lua_newtable(L);
	int methodtable = lua_gettop(L);
	luaL_newmetatable(L, className);
	int metatable = lua_gettop(L);

	lua_pushliteral(L, "__metatable");
	lua_pushvalue(L, methodtable);
	lua_settable(L, metatable);  // hide metatable from Lua getmetatable()

	lua_pushliteral(L, "__index");
	lua_pushvalue(L, methodtable);
	lua_settable(L, metatable);

	lua_pushliteral(L, "__gc");
	lua_pushcfunction(L, gc_object);
	lua_settable(L, metatable);

	lua_pop(L, 1);  // drop metatable

	luaL_openlib(L, 0, methods, 0);  // fill methodtable
	lua_pop(L, 1);  // drop methodtable

	// Can be created from Lua (PerlinNoise(seed, octaves, persistence)
	lua_register(L, className, create_object);
}

const char LuaPerlinNoise::className[] = "PerlinNoise";
const luaL_reg LuaPerlinNoise::methods[] = {
	luamethod(LuaPerlinNoise, get2d),
	luamethod(LuaPerlinNoise, get3d),
	{0,0}
};

/*
  PerlinNoiseMap
 */


int LuaPerlinNoiseMap::gc_object(lua_State *L)
{
	LuaPerlinNoiseMap *o = *(LuaPerlinNoiseMap **)(lua_touserdata(L, 1));
	delete o;
	return 0;
}

int LuaPerlinNoiseMap::l_get2dMap(lua_State *L)
{
	int i = 0;

	LuaPerlinNoiseMap *o = checkobject(L, 1);
	v2f p = read_v2f(L, 2);

	Noise *n = o->noise;
	n->perlinMap2D(p.X, p.Y);

	lua_newtable(L);
	for (int y = 0; y != n->sy; y++) {
		lua_newtable(L);
		for (int x = 0; x != n->sx; x++) {
			float noiseval = n->np->offset + n->np->scale * n->result[i++];
			lua_pushnumber(L, noiseval);
			lua_rawseti(L, -2, x + 1);
		}
		lua_rawseti(L, -2, y + 1);
	}
	return 1;
}

int LuaPerlinNoiseMap::l_get3dMap(lua_State *L)
{
	int i = 0;

	LuaPerlinNoiseMap *o = checkobject(L, 1);
	v3f p = read_v3f(L, 2);

	Noise *n = o->noise;
	n->perlinMap3D(p.X, p.Y, p.Z);

	lua_newtable(L);
	for (int z = 0; z != n->sz; z++) {
		lua_newtable(L);
		for (int y = 0; y != n->sy; y++) {
			lua_newtable(L);
			for (int x = 0; x != n->sx; x++) {
				lua_pushnumber(L, n->np->offset + n->np->scale * n->result[i++]);
				lua_rawseti(L, -2, x + 1);
			}
			lua_rawseti(L, -2, y + 1);
		}
		lua_rawseti(L, -2, z + 1);
	}
	return 1;
}

LuaPerlinNoiseMap::LuaPerlinNoiseMap(NoiseParams *np, int seed, v3s16 size) {
	noise = new Noise(np, seed, size.X, size.Y, size.Z);
}

LuaPerlinNoiseMap::~LuaPerlinNoiseMap()
{
	delete noise->np;
	delete noise;
}

// LuaPerlinNoiseMap(np, size)
// Creates an LuaPerlinNoiseMap and leaves it on top of stack
int LuaPerlinNoiseMap::create_object(lua_State *L)
{
	NoiseParams *np = read_noiseparams(L, 1);
	if (!np)
		return 0;
	v3s16 size = read_v3s16(L, 2);

	LuaPerlinNoiseMap *o = new LuaPerlinNoiseMap(np, 0, size);
	*(void **)(lua_newuserdata(L, sizeof(void *))) = o;
	luaL_getmetatable(L, className);
	lua_setmetatable(L, -2);
	return 1;
}

LuaPerlinNoiseMap* LuaPerlinNoiseMap::checkobject(lua_State *L, int narg)
{
	luaL_checktype(L, narg, LUA_TUSERDATA);

	void *ud = luaL_checkudata(L, narg, className);
	if (!ud)
		luaL_typerror(L, narg, className);

	return *(LuaPerlinNoiseMap **)ud;  // unbox pointer
}

void LuaPerlinNoiseMap::Register(lua_State *L)
{
	lua_newtable(L);
	int methodtable = lua_gettop(L);
	luaL_newmetatable(L, className);
	int metatable = lua_gettop(L);

	lua_pushliteral(L, "__metatable");
	lua_pushvalue(L, methodtable);
	lua_settable(L, metatable);  // hide metatable from Lua getmetatable()

	lua_pushliteral(L, "__index");
	lua_pushvalue(L, methodtable);
	lua_settable(L, metatable);

	lua_pushliteral(L, "__gc");
	lua_pushcfunction(L, gc_object);
	lua_settable(L, metatable);

	lua_pop(L, 1);  // drop metatable

	luaL_openlib(L, 0, methods, 0);  // fill methodtable
	lua_pop(L, 1);  // drop methodtable

	// Can be created from Lua (PerlinNoiseMap(np, size)
	lua_register(L, className, create_object);
}

const char LuaPerlinNoiseMap::className[] = "PerlinNoiseMap";
const luaL_reg LuaPerlinNoiseMap::methods[] = {
	luamethod(LuaPerlinNoiseMap, get2dMap),
	luamethod(LuaPerlinNoiseMap, get3dMap),
	{0,0}
};

/*
	NoiseParams
*/
NoiseParams *read_noiseparams(lua_State *L, int index)
{
	if (index < 0)
		index = lua_gettop(L) + 1 + index;

	if (!lua_istable(L, index))
		return NULL;

	NoiseParams *np = new NoiseParams;

	np->offset  = getfloatfield_default(L, index, "offset", 0.0);
	np->scale   = getfloatfield_default(L, index, "scale", 0.0);
	lua_getfield(L, index, "spread");
	np->spread  = read_v3f(L, -1);
	lua_pop(L, 1);
	np->seed    = getintfield_default(L, index, "seed", 0);
	np->octaves = getintfield_default(L, index, "octaves", 0);
	np->persist = getfloatfield_default(L, index, "persist", 0.0);

	return np;
}


/*
	LuaPseudoRandom
*/

// garbage collector
int LuaPseudoRandom::gc_object(lua_State *L)
{
	LuaPseudoRandom *o = *(LuaPseudoRandom **)(lua_touserdata(L, 1));
	delete o;
	return 0;
}

// next(self, min=0, max=32767) -> get next value
int LuaPseudoRandom::l_next(lua_State *L)
{
	LuaPseudoRandom *o = checkobject(L, 1);
	int min = 0;
	int max = 32767;
	lua_settop(L, 3); // Fill 2 and 3 with nil if they don't exist
	if(!lua_isnil(L, 2))
		min = luaL_checkinteger(L, 2);
	if(!lua_isnil(L, 3))
		max = luaL_checkinteger(L, 3);
	if(max < min){
		errorstream<<"PseudoRandom.next(): max="<<max<<" min="<<min<<std::endl;
		throw LuaError(L, "PseudoRandom.next(): max < min");
	}
	if(max - min != 32767 && max - min > 32767/5)
		throw LuaError(L, "PseudoRandom.next() max-min is not 32767 and is > 32768/5. This is disallowed due to the bad random distribution the implementation would otherwise make.");
	PseudoRandom &pseudo = o->m_pseudo;
	int val = pseudo.next();
	val = (val % (max-min+1)) + min;
	lua_pushinteger(L, val);
	return 1;
}


LuaPseudoRandom::LuaPseudoRandom(int seed):
	m_pseudo(seed)
{
}

LuaPseudoRandom::~LuaPseudoRandom()
{
}

const PseudoRandom& LuaPseudoRandom::getItem() const
{
	return m_pseudo;
}
PseudoRandom& LuaPseudoRandom::getItem()
{
	return m_pseudo;
}

// LuaPseudoRandom(seed)
// Creates an LuaPseudoRandom and leaves it on top of stack
int LuaPseudoRandom::create_object(lua_State *L)
{
	int seed = luaL_checknumber(L, 1);
	LuaPseudoRandom *o = new LuaPseudoRandom(seed);
	*(void **)(lua_newuserdata(L, sizeof(void *))) = o;
	luaL_getmetatable(L, className);
	lua_setmetatable(L, -2);
	return 1;
}

LuaPseudoRandom* LuaPseudoRandom::checkobject(lua_State *L, int narg)
{
	luaL_checktype(L, narg, LUA_TUSERDATA);
	void *ud = luaL_checkudata(L, narg, className);
	if(!ud) luaL_typerror(L, narg, className);
	return *(LuaPseudoRandom**)ud;  // unbox pointer
}

void LuaPseudoRandom::Register(lua_State *L)
{
	lua_newtable(L);
	int methodtable = lua_gettop(L);
	luaL_newmetatable(L, className);
	int metatable = lua_gettop(L);

	lua_pushliteral(L, "__metatable");
	lua_pushvalue(L, methodtable);
	lua_settable(L, metatable);  // hide metatable from Lua getmetatable()

	lua_pushliteral(L, "__index");
	lua_pushvalue(L, methodtable);
	lua_settable(L, metatable);

	lua_pushliteral(L, "__gc");
	lua_pushcfunction(L, gc_object);
	lua_settable(L, metatable);

	lua_pop(L, 1);  // drop metatable

	luaL_openlib(L, 0, methods, 0);  // fill methodtable
	lua_pop(L, 1);  // drop methodtable

	// Can be created from Lua (LuaPseudoRandom(seed))
	lua_register(L, className, create_object);
}

const char LuaPseudoRandom::className[] = "PseudoRandom";
const luaL_reg LuaPseudoRandom::methods[] = {
	luamethod(LuaPseudoRandom, next),
	{0,0}
};