Add support for NoiseParams in minetest.get_perlin() and add docs on …

…NoiseParams to lua_api.txt

doc/lua_api.txt

@@ -482,34 +482,77 @@ A box of a regular node would look like:
 
 type = "leveled" is same as "fixed", but y2 will be automatically set to level from param2
 
+
 Meshes
 -----------
 If drawtype "mesh" is used tiles should hold model materials textures.
 Only static meshes are implemented.
 For supported model formats see Irrlicht engine documentation.
-
+
+
+Noise Parameters
+--------------------
+Noise Parameters, or commonly called NoiseParams, define the properties of perlin noise.
+ - offset
+ Offset that the noise is translated by (i.e. added) after calculation.
+ - scale
+ Factor that the noise is scaled by (i.e. multiplied) after calculation.
+ - spread
+ Vector containing values by which each coordinate is divided by before calculation.
+ Higher spread values result in larger noise features.
+ A value of {x=250, y=250, z=250} is common.
+ - seed
+ Random seed for the noise. Add the world seed to a seed offset for world-unique noise.
+ In the case of minetest.get_perlin(), this value has the world seed automatically added.
+ - octaves
+ Number of times the noise gradient is accumulated into the noise.
+ Increase this number to increase the amount of detail in the resulting noise.
+ A value of 6 is common.
+ - persistence
+ Factor by which the effect of the noise gradient function changes with each successive octave.
+ Values less than 1 make the details of successive octaves' noise diminish, while values
+ greater than 1 make successive octaves stronger.
+ A value of 0.6 is common.
+ - lacunarity
+ Factor by which the noise feature sizes change with each successive octave.
+ A value of 2.0 is common.
+ - flags
+ Leave this field unset for no special handling.
+ Currently supported are:
+ - defaults
+ Specify this if you would like to keep auto-selection of eased/not-eased while specifying
+ some other flags.
+ - eased
+ Maps noise gradient values onto a quintic S-curve before performing interpolation.
+ This results in smooth, rolling noise. Disable this for sharp-looking noise.
+ If no flags are specified (or defaults is), 2D noise is eased and 3D noise is not eased.
+ - absvalue
+ Accumulates the absolute value of each noise gradient result.
+
+
 Ore types
 ---------------
 These tell in what manner the ore is generated.
 All default ores are of the uniformly-distributed scatter type.
 
-- scatter
+ - scatter
  Randomly chooses a location and generates a cluster of ore.
  If noise_params is specified, the ore will be placed if the 3d perlin noise at
  that point is greater than the noise_threshold, giving the ability to create a non-equal
  distribution of ore.
-- sheet
+ - sheet
  Creates a sheet of ore in a blob shape according to the 2d perlin noise described by noise_params.
  The relative height of the sheet can be controlled by the same perlin noise as well, by specifying
  a non-zero 'scale' parameter in noise_params. IMPORTANT: The noise is not transformed by offset or
  scale when comparing against the noise threshold, but scale is used to determine relative height.
  The height of the blob is randomly scattered, with a maximum height of clust_size.
  clust_scarcity and clust_num_ores are ignored.
  This is essentially an improved version of the so-called "stratus" ore seen in some unofficial mods.
-- claylike - NOT YET IMPLEMENTED
+ - claylike - NOT YET IMPLEMENTED
  Places ore if there are no more than clust_scarcity number of specified nodes within a Von Neumann
  neighborhood of clust_size radius.
 
+
 Ore attributes
 -------------------
 See section Flag Specifier Format.
@@ -534,6 +577,7 @@ The default value is simple, and is currently the only type supported.
  probability of a node randomly appearing when placed. This decoration type is intended to be used
  for multi-node sized discrete structures, such as trees, cave spikes, rocks, and so on.
 
+
 Schematic specifier
 --------------------
  A schematic specifier identifies a schematic by either a filename to a Minetest Schematic file (.mts)
@@ -552,6 +596,7 @@ When passed to minetest.create_schematic, probability is an integer value rangin
 
 Important note: Node aliases cannot be used for a raw schematic provided when registering as a decoration.
 
+
 Schematic attributes
 ---------------------
 See section Flag Specifier Format.
@@ -563,6 +608,7 @@ Currently supported flags: place_center_x, place_center_y, place_center_z
  - place_center_z
  Placement of this decoration is centered along the Z axis.
 
+
 HUD element types
 -------------------
 The position field is used for all element types.
@@ -1529,6 +1575,7 @@ minetest.find_node_near(pos, radius, nodenames) -> pos or nil
 ^ nodenames: e.g. {"ignore", "group:tree"} or "default:dirt"
 minetest.find_nodes_in_area(minp, maxp, nodenames) -> list of positions
 ^ nodenames: e.g. {"ignore", "group:tree"} or "default:dirt"
+minetest.get_perlin(noiseparams)
 minetest.get_perlin(seeddiff, octaves, persistence, scale)
 ^ Return world-specific perlin noise (int(worldseed)+seeddiff)
 minetest.get_voxel_manip()
@@ -2109,8 +2156,8 @@ methods:
  implementation making bad distribution otherwise.
 
 PerlinNoise: A perlin noise generator
-- Can be created via PerlinNoise(seed, octaves, persistence, scale)
-- Also minetest.get_perlin(seeddiff, octaves, persistence, scale)
+- Can be created via PerlinNoise(seed, octaves, persistence, scale) or PerlinNoise(noiseparams)
+- Also minetest.get_perlin(seeddiff, octaves, persistence, scale) or minetest.get_perlin(noiseparams)
 methods:
 - get2d(pos) -> 2d noise value at pos={x=,y=}
 - get3d(pos) -> 3d noise value at pos={x=,y=,z=}

src/script/lua_api/l_env.cpp

@@ -590,12 +590,20 @@ int ModApiEnvMod::l_get_perlin(lua_State *L)
 {
  GET_ENV_PTR;
 
- int seeddiff = luaL_checkint(L, 1);
- int octaves = luaL_checkint(L, 2);
- float persistence = luaL_checknumber(L, 3);
- float scale = luaL_checknumber(L, 4);
+ NoiseParams params;
 
- LuaPerlinNoise *n = new LuaPerlinNoise(seeddiff + int(env->getServerMap().getSeed()), octaves, persistence, scale);
+ if (lua_istable(L, 1)) {
+ read_noiseparams(L, 1, &params);
+ } else {
+ params.seed = luaL_checkint(L, 1);
+ params.octaves = luaL_checkint(L, 2);
+ params.persist = luaL_checknumber(L, 3);
+ params.spread = v3f(1, 1, 1) * luaL_checknumber(L, 4);
+ }
+
+ params.seed += (int)env->getServerMap().getSeed();
+
+ LuaPerlinNoise *n = new LuaPerlinNoise(&params);
  *(void **)(lua_newuserdata(L, sizeof(void *))) = n;
  luaL_getmetatable(L, "PerlinNoise");
  lua_setmetatable(L, -2);

src/script/lua_api/l_noise.cpp

@@ -36,8 +36,8 @@ int LuaPerlinNoise::l_get2d(lua_State *L)
 {
  NO_MAP_LOCK_REQUIRED;
  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);
+ v2f p = read_v2f(L, 2);
+ lua_Number val = NoisePerlin2D(&o->np, p.X, p.Y, 0);
  lua_pushnumber(L, val);
  return 1;
 }
@@ -47,23 +47,30 @@ int LuaPerlinNoise::l_get3d(lua_State *L)
 {
  NO_MAP_LOCK_REQUIRED;
  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);
+ v3f p = read_v3f(L, 2);
+ lua_Number val = NoisePerlin3D(&o->np, p.X, p.Y, p.Z, 0);
  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(NoiseParams *params) :
+ np(*params)
 {
 }
 
 
+/*
+LuaPerlinNoise::LuaPerlinNoise(int a_seed, int a_octaves,
+ float a_persistence, float a_scale)
+{
+ np.seed = a_seed;
+ np.octaves = a_octaves;
+ np.persist = a_persistence;
+ np.spread = v3f(a_scale, a_scale, a_scale);
+}
+*/
+
 LuaPerlinNoise::~LuaPerlinNoise()
 {
 }
@@ -74,11 +81,20 @@ LuaPerlinNoise::~LuaPerlinNoise()
 int LuaPerlinNoise::create_object(lua_State *L)
 {
  NO_MAP_LOCK_REQUIRED;
- 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);
+
+ NoiseParams params;
+
+ if (lua_istable(L, 1)) {
+ read_noiseparams(L, 1, &params);
+ } else {
+ params.seed = luaL_checkint(L, 1);
+ params.octaves = luaL_checkint(L, 2);
+ params.persist = luaL_checknumber(L, 3);
+ params.spread = v3f(1, 1, 1) * luaL_checknumber(L, 4);
+ }
+
+ LuaPerlinNoise *o = new LuaPerlinNoise(&params);
+
  *(void **)(lua_newuserdata(L, sizeof(void *))) = o;
  luaL_getmetatable(L, className);
  lua_setmetatable(L, -2);

src/script/lua_api/l_noise.h

@@ -29,10 +29,8 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 */
 class LuaPerlinNoise : public ModApiBase {
 private:
- int seed;
- int octaves;
- float persistence;
- float scale;
+ NoiseParams np;
+
  static const char className[];
  static const luaL_reg methods[];
 
@@ -45,9 +43,7 @@ class LuaPerlinNoise : public ModApiBase {
  static int l_get3d(lua_State *L);
 
 public:
- LuaPerlinNoise(int a_seed, int a_octaves, float a_persistence,
- float a_scale);
-
+ LuaPerlinNoise(NoiseParams *params);
  ~LuaPerlinNoise();
 
  // LuaPerlinNoise(seed, octaves, persistence, scale)