src/script/common/c_content.cpp

   1 /*
   2 Minetest
   3 Copyright (C) 2013 celeron55, Perttu Ahola <celeron55@gmail.com>
   4
   5 This program is free software; you can redistribute it and/or modify
   6 it under the terms of the GNU Lesser General Public License as published by
   7 the Free Software Foundation; either version 2.1 of the License, or
   8 (at your option) any later version.
   9
  10 This program is distributed in the hope that it will be useful,
  11 but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 GNU Lesser General Public License for more details.
  14
  15 You should have received a copy of the GNU Lesser General Public License along
  16 with this program; if not, write to the Free Software Foundation, Inc.,
  17 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  18 */
  19 #include "common/c_content.h"
  20 #include "common/c_converter.h"
  21 #include "common/c_types.h"
  22 #include "nodedef.h"
  23 #include "itemdef.h"
  24 #include "object_properties.h"
  25 #include "cpp_api/s_node.h"
  26 #include "lua_api/l_object.h"
  27 #include "lua_api/l_item.h"
  28 #include "common/c_internal.h"
  29 #include "server.h"
  30 #include "log.h"
  31 #include "tool.h"
  32 #include "serverobject.h"
  33 #include "porting.h"
  34 #include "mg_schematic.h"
  35 #include "noise.h"
  36 #include "json/json.h"
  37
  38 struct EnumString es_TileAnimationType[] =
  39 {
  40         {TAT_NONE, "none"},
  41         {TAT_VERTICAL_FRAMES, "vertical_frames"},
  42         {0, NULL},
  43 };
  44
  45 /******************************************************************************/
  46 ItemDefinition read_item_definition(lua_State* L,int index,
  47                 ItemDefinition default_def)
  48 {
  49         if(index < 0)
  50                 index = lua_gettop(L) + 1 + index;
  51
  52         // Read the item definition
  53         ItemDefinition def = default_def;
  54
  55         def.type = (ItemType)getenumfield(L, index, "type",
  56                         es_ItemType, ITEM_NONE);
  57         getstringfield(L, index, "name", def.name);
  58         getstringfield(L, index, "description", def.description);
  59         getstringfield(L, index, "inventory_image", def.inventory_image);
  60         getstringfield(L, index, "wield_image", def.wield_image);
  61
  62         lua_getfield(L, index, "wield_scale");
  63         if(lua_istable(L, -1)){
  64                 def.wield_scale = check_v3f(L, -1);
  65         }
  66         lua_pop(L, 1);
  67
  68         def.stack_max = getintfield_default(L, index, "stack_max", def.stack_max);
  69         if(def.stack_max == 0)
  70                 def.stack_max = 1;
  71
  72         lua_getfield(L, index, "on_use");
  73         def.usable = lua_isfunction(L, -1);
  74         lua_pop(L, 1);
  75
  76         getboolfield(L, index, "liquids_pointable", def.liquids_pointable);
  77
  78         warn_if_field_exists(L, index, "tool_digging_properties",
  79                         "deprecated: use tool_capabilities");
  80
  81         lua_getfield(L, index, "tool_capabilities");
  82         if(lua_istable(L, -1)){
  83                 def.tool_capabilities = new ToolCapabilities(
  84                                 read_tool_capabilities(L, -1));
  85         }
  86
  87         // If name is "" (hand), ensure there are ToolCapabilities
  88         // because it will be looked up there whenever any other item has
  89         // no ToolCapabilities
  90         if(def.name == "" && def.tool_capabilities == NULL){
  91                 def.tool_capabilities = new ToolCapabilities();
  92         }
  93
  94         lua_getfield(L, index, "groups");
  95         read_groups(L, -1, def.groups);
  96         lua_pop(L, 1);
  97
  98         lua_getfield(L, index, "sounds");
  99         if(lua_istable(L, -1)){
 100                 lua_getfield(L, -1, "place");
 101                 read_soundspec(L, -1, def.sound_place);
 102                 lua_pop(L, 1);
 103         }
 104         lua_pop(L, 1);
 105
 106         def.range = getfloatfield_default(L, index, "range", def.range);
 107
 108         // Client shall immediately place this node when player places the item.
 109         // Server will update the precise end result a moment later.
 110         // "" = no prediction
 111         getstringfield(L, index, "node_placement_prediction",
 112                         def.node_placement_prediction);
 113
 114         return def;
 115 }
 116
 117 /******************************************************************************/
 118 void read_object_properties(lua_State *L, int index,
 119                 ObjectProperties *prop)
 120 {
 121         if(index < 0)
 122                 index = lua_gettop(L) + 1 + index;
 123         if(!lua_istable(L, index))
 124                 return;
 125
 126         prop->hp_max = getintfield_default(L, -1, "hp_max", 10);
 127
 128         getboolfield(L, -1, "physical", prop->physical);
 129         getboolfield(L, -1, "collide_with_objects", prop->collideWithObjects);
 130
 131         getfloatfield(L, -1, "weight", prop->weight);
 132
 133         lua_getfield(L, -1, "collisionbox");
 134         if(lua_istable(L, -1))
 135                 prop->collisionbox = read_aabb3f(L, -1, 1.0);
 136         lua_pop(L, 1);
 137
 138         getstringfield(L, -1, "visual", prop->visual);
 139
 140         getstringfield(L, -1, "mesh", prop->mesh);
 141
 142         lua_getfield(L, -1, "visual_size");
 143         if(lua_istable(L, -1))
 144                 prop->visual_size = read_v2f(L, -1);
 145         lua_pop(L, 1);
 146
 147         lua_getfield(L, -1, "textures");
 148         if(lua_istable(L, -1)){
 149                 prop->textures.clear();
 150                 int table = lua_gettop(L);
 151                 lua_pushnil(L);
 152                 while(lua_next(L, table) != 0){
 153                         // key at index -2 and value at index -1
 154                         if(lua_isstring(L, -1))
 155                                 prop->textures.push_back(lua_tostring(L, -1));
 156                         else
 157                                 prop->textures.push_back("");
 158                         // removes value, keeps key for next iteration
 159                         lua_pop(L, 1);
 160                 }
 161         }
 162         lua_pop(L, 1);
 163
 164         lua_getfield(L, -1, "colors");
 165         if (lua_istable(L, -1)) {
 166                 int table = lua_gettop(L);
 167                 prop->colors.clear();
 168                 for (lua_pushnil(L); lua_next(L, table); lua_pop(L, 1)) {
 169                         video::SColor color(255, 255, 255, 255);
 170                         read_color(L, -1, &color);
 171                         prop->colors.push_back(color);
 172                 }
 173         }
 174         lua_pop(L, 1);
 175
 176         lua_getfield(L, -1, "spritediv");
 177         if(lua_istable(L, -1))
 178                 prop->spritediv = read_v2s16(L, -1);
 179         lua_pop(L, 1);
 180
 181         lua_getfield(L, -1, "initial_sprite_basepos");
 182         if(lua_istable(L, -1))
 183                 prop->initial_sprite_basepos = read_v2s16(L, -1);
 184         lua_pop(L, 1);
 185
 186         getboolfield(L, -1, "is_visible", prop->is_visible);
 187         getboolfield(L, -1, "makes_footstep_sound", prop->makes_footstep_sound);
 188         getfloatfield(L, -1, "automatic_rotate", prop->automatic_rotate);
 189         if (getfloatfield(L, -1, "stepheight", prop->stepheight))
 190                 prop->stepheight *= BS;
 191         lua_getfield(L, -1, "automatic_face_movement_dir");
 192         if (lua_isnumber(L, -1)) {
 193                 prop->automatic_face_movement_dir = true;
 194                 prop->automatic_face_movement_dir_offset = luaL_checknumber(L, -1);
 195         } else if (lua_isboolean(L, -1)) {
 196                 prop->automatic_face_movement_dir = lua_toboolean(L, -1);
 197                 prop->automatic_face_movement_dir_offset = 0.0;
 198         }
 199         lua_pop(L, 1);
 200 }
 201
 202 /******************************************************************************/
 203 void push_object_properties(lua_State *L, ObjectProperties *prop)
 204 {
 205         lua_newtable(L);
 206         lua_pushnumber(L, prop->hp_max);
 207         lua_setfield(L, -2, "hp_max");
 208         lua_pushboolean(L, prop->physical);
 209         lua_setfield(L, -2, "physical");
 210         lua_pushboolean(L, prop->collideWithObjects);
 211         lua_setfield(L, -2, "collide_with_objects");
 212         lua_pushnumber(L, prop->weight);
 213         lua_setfield(L, -2, "weight");
 214         push_aabb3f(L, prop->collisionbox);
 215         lua_setfield(L, -2, "collisionbox");
 216         lua_pushlstring(L, prop->visual.c_str(), prop->visual.size());
 217         lua_setfield(L, -2, "visual");
 218         lua_pushlstring(L, prop->mesh.c_str(), prop->mesh.size());
 219         lua_setfield(L, -2, "mesh");
 220         push_v2f(L, prop->visual_size);
 221         lua_setfield(L, -2, "visual_size");
 222
 223         lua_newtable(L);
 224         u16 i = 1;
 225         for (std::vector<std::string>::iterator it = prop->textures.begin();
 226                         it != prop->textures.end(); ++it) {
 227                 lua_pushlstring(L, it->c_str(), it->size());
 228                 lua_rawseti(L, -2, i);
 229         }
 230         lua_setfield(L, -2, "textures");
 231
 232         lua_newtable(L);
 233         i = 1;
 234         for (std::vector<video::SColor>::iterator it = prop->colors.begin();
 235                         it != prop->colors.end(); ++it) {
 236                 push_ARGB8(L, *it);
 237                 lua_rawseti(L, -2, i);
 238         }
 239         lua_setfield(L, -2, "colors");
 240
 241         push_v2s16(L, prop->spritediv);
 242         lua_setfield(L, -2, "spritediv");
 243         push_v2s16(L, prop->initial_sprite_basepos);
 244         lua_setfield(L, -2, "initial_sprite_basepos");
 245         lua_pushboolean(L, prop->is_visible);
 246         lua_setfield(L, -2, "is_visible");
 247         lua_pushboolean(L, prop->makes_footstep_sound);
 248         lua_setfield(L, -2, "makes_footstep_sound");
 249         lua_pushnumber(L, prop->automatic_rotate);
 250         lua_setfield(L, -2, "automatic_rotate");
 251         lua_pushnumber(L, prop->stepheight / BS);
 252         lua_setfield(L, -2, "stepheight");
 253         if (prop->automatic_face_movement_dir)
 254                 lua_pushnumber(L, prop->automatic_face_movement_dir_offset);
 255         else
 256                 lua_pushboolean(L, false);
 257         lua_setfield(L, -2, "automatic_face_movement_dir");
 258 }
 259
 260 /******************************************************************************/
 261 TileDef read_tiledef(lua_State *L, int index, u8 drawtype)
 262 {
 263         if(index < 0)
 264                 index = lua_gettop(L) + 1 + index;
 265
 266         TileDef tiledef;
 267         bool default_tiling = (drawtype == NDT_PLANTLIKE || drawtype == NDT_FIRELIKE)
 268                 ? false : true;
 269         // key at index -2 and value at index
 270         if(lua_isstring(L, index)){
 271                 // "default_lava.png"
 272                 tiledef.name = lua_tostring(L, index);
 273                 tiledef.tileable_vertical = default_tiling;
 274                 tiledef.tileable_horizontal = default_tiling;
 275         }
 276         else if(lua_istable(L, index))
 277         {
 278                 // {name="default_lava.png", animation={}}
 279                 tiledef.name = "";
 280                 getstringfield(L, index, "name", tiledef.name);
 281                 getstringfield(L, index, "image", tiledef.name); // MaterialSpec compat.
 282                 tiledef.backface_culling = getboolfield_default(
 283                         L, index, "backface_culling", true);
 284                 tiledef.tileable_horizontal = getboolfield_default(
 285                         L, index, "tileable_horizontal", default_tiling);
 286                 tiledef.tileable_vertical = getboolfield_default(
 287                         L, index, "tileable_vertical", default_tiling);
 288                 // animation = {}
 289                 lua_getfield(L, index, "animation");
 290                 if(lua_istable(L, -1)){
 291                         // {type="vertical_frames", aspect_w=16, aspect_h=16, length=2.0}
 292                         tiledef.animation.type = (TileAnimationType)
 293                                 getenumfield(L, -1, "type", es_TileAnimationType,
 294                                 TAT_NONE);
 295                         tiledef.animation.aspect_w =
 296                                 getintfield_default(L, -1, "aspect_w", 16);
 297                         tiledef.animation.aspect_h =
 298                                 getintfield_default(L, -1, "aspect_h", 16);
 299                         tiledef.animation.length =
 300                                 getfloatfield_default(L, -1, "length", 1.0);
 301                 }
 302                 lua_pop(L, 1);
 303         }
 304
 305         return tiledef;
 306 }
 307
 308 /******************************************************************************/
 309 ContentFeatures read_content_features(lua_State *L, int index)
 310 {
 311         if(index < 0)
 312                 index = lua_gettop(L) + 1 + index;
 313
 314         ContentFeatures f;
 315
 316         /* Cache existence of some callbacks */
 317         lua_getfield(L, index, "on_construct");
 318         if(!lua_isnil(L, -1)) f.has_on_construct = true;
 319         lua_pop(L, 1);
 320         lua_getfield(L, index, "on_destruct");
 321         if(!lua_isnil(L, -1)) f.has_on_destruct = true;
 322         lua_pop(L, 1);
 323         lua_getfield(L, index, "after_destruct");
 324         if(!lua_isnil(L, -1)) f.has_after_destruct = true;
 325         lua_pop(L, 1);
 326
 327         lua_getfield(L, index, "on_rightclick");
 328         f.rightclickable = lua_isfunction(L, -1);
 329         lua_pop(L, 1);
 330
 331         /* Name */
 332         getstringfield(L, index, "name", f.name);
 333
 334         /* Groups */
 335         lua_getfield(L, index, "groups");
 336         read_groups(L, -1, f.groups);
 337         lua_pop(L, 1);
 338
 339         /* Visual definition */
 340
 341         f.drawtype = (NodeDrawType)getenumfield(L, index, "drawtype",
 342                         ScriptApiNode::es_DrawType,NDT_NORMAL);
 343         getfloatfield(L, index, "visual_scale", f.visual_scale);
 344
 345         /* Meshnode model filename */
 346         getstringfield(L, index, "mesh", f.mesh);
 347
 348         // tiles = {}
 349         lua_getfield(L, index, "tiles");
 350         // If nil, try the deprecated name "tile_images" instead
 351         if(lua_isnil(L, -1)){
 352                 lua_pop(L, 1);
 353                 warn_if_field_exists(L, index, "tile_images",
 354                                 "Deprecated; new name is \"tiles\".");
 355                 lua_getfield(L, index, "tile_images");
 356         }
 357         if(lua_istable(L, -1)){
 358                 int table = lua_gettop(L);
 359                 lua_pushnil(L);
 360                 int i = 0;
 361                 while(lua_next(L, table) != 0){
 362                         // Read tiledef from value
 363                         f.tiledef[i] = read_tiledef(L, -1, f.drawtype);
 364                         // removes value, keeps key for next iteration
 365                         lua_pop(L, 1);
 366                         i++;
 367                         if(i==6){
 368                                 lua_pop(L, 1);
 369                                 break;
 370                         }
 371                 }
 372                 // Copy last value to all remaining textures
 373                 if(i >= 1){
 374                         TileDef lasttile = f.tiledef[i-1];
 375                         while(i < 6){
 376                                 f.tiledef[i] = lasttile;
 377                                 i++;
 378                         }
 379                 }
 380         }
 381         lua_pop(L, 1);
 382
 383         // special_tiles = {}
 384         lua_getfield(L, index, "special_tiles");
 385         // If nil, try the deprecated name "special_materials" instead
 386         if(lua_isnil(L, -1)){
 387                 lua_pop(L, 1);
 388                 warn_if_field_exists(L, index, "special_materials",
 389                                 "Deprecated; new name is \"special_tiles\".");
 390                 lua_getfield(L, index, "special_materials");
 391         }
 392         if(lua_istable(L, -1)){
 393                 int table = lua_gettop(L);
 394                 lua_pushnil(L);
 395                 int i = 0;
 396                 while(lua_next(L, table) != 0){
 397                         // Read tiledef from value
 398                         f.tiledef_special[i] = read_tiledef(L, -1, f.drawtype);
 399                         // removes value, keeps key for next iteration
 400                         lua_pop(L, 1);
 401                         i++;
 402                         if(i==CF_SPECIAL_COUNT){
 403                                 lua_pop(L, 1);
 404                                 break;
 405                         }
 406                 }
 407         }
 408         lua_pop(L, 1);
 409
 410         f.alpha = getintfield_default(L, index, "alpha", 255);
 411
 412         bool usealpha = getboolfield_default(L, index,
 413                         "use_texture_alpha", false);
 414         if (usealpha)
 415                 f.alpha = 0;
 416
 417         /* Other stuff */
 418
 419         lua_getfield(L, index, "post_effect_color");
 420         read_color(L, -1, &f.post_effect_color);
 421         lua_pop(L, 1);
 422
 423         f.param_type = (ContentParamType)getenumfield(L, index, "paramtype",
 424                         ScriptApiNode::es_ContentParamType, CPT_NONE);
 425         f.param_type_2 = (ContentParamType2)getenumfield(L, index, "paramtype2",
 426                         ScriptApiNode::es_ContentParamType2, CPT2_NONE);
 427
 428         // Warn about some deprecated fields
 429         warn_if_field_exists(L, index, "wall_mounted",
 430                         "deprecated: use paramtype2 = 'wallmounted'");
 431         warn_if_field_exists(L, index, "light_propagates",
 432                         "deprecated: determined from paramtype");
 433         warn_if_field_exists(L, index, "dug_item",
 434                         "deprecated: use 'drop' field");
 435         warn_if_field_exists(L, index, "extra_dug_item",
 436                         "deprecated: use 'drop' field");
 437         warn_if_field_exists(L, index, "extra_dug_item_rarity",
 438                         "deprecated: use 'drop' field");
 439         warn_if_field_exists(L, index, "metadata_name",
 440                         "deprecated: use on_add and metadata callbacks");
 441
 442         // True for all ground-like things like stone and mud, false for eg. trees
 443         getboolfield(L, index, "is_ground_content", f.is_ground_content);
 444         f.light_propagates = (f.param_type == CPT_LIGHT);
 445         getboolfield(L, index, "sunlight_propagates", f.sunlight_propagates);
 446         // This is used for collision detection.
 447         // Also for general solidness queries.
 448         getboolfield(L, index, "walkable", f.walkable);
 449         // Player can point to these
 450         getboolfield(L, index, "pointable", f.pointable);
 451         // Player can dig these
 452         getboolfield(L, index, "diggable", f.diggable);
 453         // Player can climb these
 454         getboolfield(L, index, "climbable", f.climbable);
 455         // Player can build on these
 456         getboolfield(L, index, "buildable_to", f.buildable_to);
 457         // Whether the node is non-liquid, source liquid or flowing liquid
 458         f.liquid_type = (LiquidType)getenumfield(L, index, "liquidtype",
 459                         ScriptApiNode::es_LiquidType, LIQUID_NONE);
 460         // If the content is liquid, this is the flowing version of the liquid.
 461         getstringfield(L, index, "liquid_alternative_flowing",
 462                         f.liquid_alternative_flowing);
 463         // If the content is liquid, this is the source version of the liquid.
 464         getstringfield(L, index, "liquid_alternative_source",
 465                         f.liquid_alternative_source);
 466         // Viscosity for fluid flow, ranging from 1 to 7, with
 467         // 1 giving almost instantaneous propagation and 7 being
 468         // the slowest possible
 469         f.liquid_viscosity = getintfield_default(L, index,
 470                         "liquid_viscosity", f.liquid_viscosity);
 471         f.liquid_range = getintfield_default(L, index,
 472                         "liquid_range", f.liquid_range);
 473         f.leveled = getintfield_default(L, index, "leveled", f.leveled);
 474
 475         getboolfield(L, index, "liquid_renewable", f.liquid_renewable);
 476         f.drowning = getintfield_default(L, index,
 477                         "drowning", f.drowning);
 478         // Amount of light the node emits
 479         f.light_source = getintfield_default(L, index,
 480                         "light_source", f.light_source);
 481         f.damage_per_second = getintfield_default(L, index,
 482                         "damage_per_second", f.damage_per_second);
 483
 484         lua_getfield(L, index, "node_box");
 485         if(lua_istable(L, -1))
 486                 f.node_box = read_nodebox(L, -1);
 487         lua_pop(L, 1);
 488
 489         lua_getfield(L, index, "selection_box");
 490         if(lua_istable(L, -1))
 491                 f.selection_box = read_nodebox(L, -1);
 492         lua_pop(L, 1);
 493
 494         lua_getfield(L, index, "collision_box");
 495         if(lua_istable(L, -1))
 496                 f.collision_box = read_nodebox(L, -1);
 497         lua_pop(L, 1);
 498
 499         f.waving = getintfield_default(L, index,
 500                         "waving", f.waving);
 501
 502         // Set to true if paramtype used to be 'facedir_simple'
 503         getboolfield(L, index, "legacy_facedir_simple", f.legacy_facedir_simple);
 504         // Set to true if wall_mounted used to be set to true
 505         getboolfield(L, index, "legacy_wallmounted", f.legacy_wallmounted);
 506
 507         // Sound table
 508         lua_getfield(L, index, "sounds");
 509         if(lua_istable(L, -1)){
 510                 lua_getfield(L, -1, "footstep");
 511                 read_soundspec(L, -1, f.sound_footstep);
 512                 lua_pop(L, 1);
 513                 lua_getfield(L, -1, "dig");
 514                 read_soundspec(L, -1, f.sound_dig);
 515                 lua_pop(L, 1);
 516                 lua_getfield(L, -1, "dug");
 517                 read_soundspec(L, -1, f.sound_dug);
 518                 lua_pop(L, 1);
 519         }
 520         lua_pop(L, 1);
 521
 522         return f;
 523 }
 524
 525 /******************************************************************************/
 526 void read_server_sound_params(lua_State *L, int index,
 527                 ServerSoundParams &params)
 528 {
 529         if(index < 0)
 530                 index = lua_gettop(L) + 1 + index;
 531         // Clear
 532         params = ServerSoundParams();
 533         if(lua_istable(L, index)){
 534                 getfloatfield(L, index, "gain", params.gain);
 535                 getstringfield(L, index, "to_player", params.to_player);
 536                 lua_getfield(L, index, "pos");
 537                 if(!lua_isnil(L, -1)){
 538                         v3f p = read_v3f(L, -1)*BS;
 539                         params.pos = p;
 540                         params.type = ServerSoundParams::SSP_POSITIONAL;
 541                 }
 542                 lua_pop(L, 1);
 543                 lua_getfield(L, index, "object");
 544                 if(!lua_isnil(L, -1)){
 545                         ObjectRef *ref = ObjectRef::checkobject(L, -1);
 546                         ServerActiveObject *sao = ObjectRef::getobject(ref);
 547                         if(sao){
 548                                 params.object = sao->getId();
 549                                 params.type = ServerSoundParams::SSP_OBJECT;
 550                         }
 551                 }
 552                 lua_pop(L, 1);
 553                 params.max_hear_distance = BS*getfloatfield_default(L, index,
 554                                 "max_hear_distance", params.max_hear_distance/BS);
 555                 getboolfield(L, index, "loop", params.loop);
 556         }
 557 }
 558
 559 /******************************************************************************/
 560 void read_soundspec(lua_State *L, int index, SimpleSoundSpec &spec)
 561 {
 562         if(index < 0)
 563                 index = lua_gettop(L) + 1 + index;
 564         if(lua_isnil(L, index)){
 565         } else if(lua_istable(L, index)){
 566                 getstringfield(L, index, "name", spec.name);
 567                 getfloatfield(L, index, "gain", spec.gain);
 568         } else if(lua_isstring(L, index)){
 569                 spec.name = lua_tostring(L, index);
 570         }
 571 }
 572
 573 /******************************************************************************/
 574 NodeBox read_nodebox(lua_State *L, int index)
 575 {
 576         NodeBox nodebox;
 577         if(lua_istable(L, -1)){
 578                 nodebox.type = (NodeBoxType)getenumfield(L, index, "type",
 579                                 ScriptApiNode::es_NodeBoxType, NODEBOX_REGULAR);
 580
 581                 lua_getfield(L, index, "fixed");
 582                 if(lua_istable(L, -1))
 583                         nodebox.fixed = read_aabb3f_vector(L, -1, BS);
 584                 lua_pop(L, 1);
 585
 586                 lua_getfield(L, index, "wall_top");
 587                 if(lua_istable(L, -1))
 588                         nodebox.wall_top = read_aabb3f(L, -1, BS);
 589                 lua_pop(L, 1);
 590
 591                 lua_getfield(L, index, "wall_bottom");
 592                 if(lua_istable(L, -1))
 593                         nodebox.wall_bottom = read_aabb3f(L, -1, BS);
 594                 lua_pop(L, 1);
 595
 596                 lua_getfield(L, index, "wall_side");
 597                 if(lua_istable(L, -1))
 598                         nodebox.wall_side = read_aabb3f(L, -1, BS);
 599                 lua_pop(L, 1);
 600         }
 601         return nodebox;
 602 }
 603
 604 /******************************************************************************/
 605 MapNode readnode(lua_State *L, int index, INodeDefManager *ndef)
 606 {
 607         lua_getfield(L, index, "name");
 608         if (!lua_isstring(L, -1))
 609                 throw LuaError("Node name is not set or is not a string!");
 610         const char *name = lua_tostring(L, -1);
 611         lua_pop(L, 1);
 612
 613         u8 param1 = 0;
 614         lua_getfield(L, index, "param1");
 615         if (!lua_isnil(L, -1))
 616                 param1 = lua_tonumber(L, -1);
 617         lua_pop(L, 1);
 618
 619         u8 param2 = 0;
 620         lua_getfield(L, index, "param2");
 621         if (!lua_isnil(L, -1))
 622                 param2 = lua_tonumber(L, -1);
 623         lua_pop(L, 1);
 624
 625         return MapNode(ndef, name, param1, param2);
 626 }
 627
 628 /******************************************************************************/
 629 void pushnode(lua_State *L, const MapNode &n, INodeDefManager *ndef)
 630 {
 631         lua_newtable(L);
 632         lua_pushstring(L, ndef->get(n).name.c_str());
 633         lua_setfield(L, -2, "name");
 634         lua_pushnumber(L, n.getParam1());
 635         lua_setfield(L, -2, "param1");
 636         lua_pushnumber(L, n.getParam2());
 637         lua_setfield(L, -2, "param2");
 638 }
 639
 640 /******************************************************************************/
 641 void warn_if_field_exists(lua_State *L, int table,
 642                 const char *fieldname, const std::string &message)
 643 {
 644         lua_getfield(L, table, fieldname);
 645         if(!lua_isnil(L, -1)){
 646 //TODO find way to access backtrace fct from here
 647                 //              infostream<<script_get_backtrace(L)<<std::endl;
 648                 infostream<<"WARNING: field \""<<fieldname<<"\": "
 649                                 <<message<<std::endl;
 650         }
 651         lua_pop(L, 1);
 652 }
 653
 654 /******************************************************************************/
 655 int getenumfield(lua_State *L, int table,
 656                 const char *fieldname, const EnumString *spec, int default_)
 657 {
 658         int result = default_;
 659         string_to_enum(spec, result,
 660                         getstringfield_default(L, table, fieldname, ""));
 661         return result;
 662 }
 663
 664 /******************************************************************************/
 665 bool string_to_enum(const EnumString *spec, int &result,
 666                 const std::string &str)
 667 {
 668         const EnumString *esp = spec;
 669         while(esp->str){
 670                 if(str == std::string(esp->str)){
 671                         result = esp->num;
 672                         return true;
 673                 }
 674                 esp++;
 675         }
 676         return false;
 677 }
 678
 679 /******************************************************************************/
 680 ItemStack read_item(lua_State* L, int index,Server* srv)
 681 {
 682         if(index < 0)
 683                 index = lua_gettop(L) + 1 + index;
 684
 685         if(lua_isnil(L, index))
 686         {
 687                 return ItemStack();
 688         }
 689         else if(lua_isuserdata(L, index))
 690         {
 691                 // Convert from LuaItemStack
 692                 LuaItemStack *o = LuaItemStack::checkobject(L, index);
 693                 return o->getItem();
 694         }
 695         else if(lua_isstring(L, index))
 696         {
 697                 // Convert from itemstring
 698                 std::string itemstring = lua_tostring(L, index);
 699                 IItemDefManager *idef = srv->idef();
 700                 try
 701                 {
 702                         ItemStack item;
 703                         item.deSerialize(itemstring, idef);
 704                         return item;
 705                 }
 706                 catch(SerializationError &e)
 707                 {
 708                         infostream<<"WARNING: unable to create item from itemstring"
 709                                         <<": "<<itemstring<<std::endl;
 710                         return ItemStack();
 711                 }
 712         }
 713         else if(lua_istable(L, index))
 714         {
 715                 // Convert from table
 716                 IItemDefManager *idef = srv->idef();
 717                 std::string name = getstringfield_default(L, index, "name", "");
 718                 int count = getintfield_default(L, index, "count", 1);
 719                 int wear = getintfield_default(L, index, "wear", 0);
 720                 std::string metadata = getstringfield_default(L, index, "metadata", "");
 721                 return ItemStack(name, count, wear, metadata, idef);
 722         }
 723         else
 724         {
 725                 throw LuaError("Expecting itemstack, itemstring, table or nil");
 726         }
 727 }
 728
 729 /******************************************************************************/
 730 void push_tool_capabilities(lua_State *L,
 731                 const ToolCapabilities &toolcap)
 732 {
 733         lua_newtable(L);
 734         setfloatfield(L, -1, "full_punch_interval", toolcap.full_punch_interval);
 735                 setintfield(L, -1, "max_drop_level", toolcap.max_drop_level);
 736                 // Create groupcaps table
 737                 lua_newtable(L);
 738                 // For each groupcap
 739                 for(std::map<std::string, ToolGroupCap>::const_iterator
 740                                 i = toolcap.groupcaps.begin(); i != toolcap.groupcaps.end(); i++){
 741                         // Create groupcap table
 742                         lua_newtable(L);
 743                         const std::string &name = i->first;
 744                         const ToolGroupCap &groupcap = i->second;
 745                         // Create subtable "times"
 746                         lua_newtable(L);
 747                         for(std::map<int, float>::const_iterator
 748                                         i = groupcap.times.begin(); i != groupcap.times.end(); i++){
 749                                 int rating = i->first;
 750                                 float time = i->second;
 751                                 lua_pushinteger(L, rating);
 752                                 lua_pushnumber(L, time);
 753                                 lua_settable(L, -3);
 754                         }
 755                         // Set subtable "times"
 756                         lua_setfield(L, -2, "times");
 757                         // Set simple parameters
 758                         setintfield(L, -1, "maxlevel", groupcap.maxlevel);
 759                         setintfield(L, -1, "uses", groupcap.uses);
 760                         // Insert groupcap table into groupcaps table
 761                         lua_setfield(L, -2, name.c_str());
 762                 }
 763                 // Set groupcaps table
 764                 lua_setfield(L, -2, "groupcaps");
 765                 //Create damage_groups table
 766                 lua_newtable(L);
 767                 // For each damage group
 768                 for(std::map<std::string, s16>::const_iterator
 769                                 i = toolcap.damageGroups.begin(); i != toolcap.damageGroups.end(); i++){
 770                         // Create damage group table
 771                         lua_pushinteger(L, i->second);
 772                         lua_setfield(L, -2, i->first.c_str());
 773                 }
 774                 lua_setfield(L, -2, "damage_groups");
 775 }
 776
 777 /******************************************************************************/
 778 void push_inventory_list(lua_State *L, Inventory *inv, const char *name)
 779 {
 780         InventoryList *invlist = inv->getList(name);
 781         if(invlist == NULL){
 782                 lua_pushnil(L);
 783                 return;
 784         }
 785         std::vector<ItemStack> items;
 786         for(u32 i=0; i<invlist->getSize(); i++)
 787                 items.push_back(invlist->getItem(i));
 788         push_items(L, items);
 789 }
 790
 791 /******************************************************************************/
 792 void read_inventory_list(lua_State *L, int tableindex,
 793                 Inventory *inv, const char *name, Server* srv, int forcesize)
 794 {
 795         if(tableindex < 0)
 796                 tableindex = lua_gettop(L) + 1 + tableindex;
 797         // If nil, delete list
 798         if(lua_isnil(L, tableindex)){
 799                 inv->deleteList(name);
 800                 return;
 801         }
 802         // Otherwise set list
 803         std::vector<ItemStack> items = read_items(L, tableindex,srv);
 804         int listsize = (forcesize != -1) ? forcesize : items.size();
 805         InventoryList *invlist = inv->addList(name, listsize);
 806         int index = 0;
 807         for(std::vector<ItemStack>::const_iterator
 808                         i = items.begin(); i != items.end(); i++){
 809                 if(forcesize != -1 && index == forcesize)
 810                         break;
 811                 invlist->changeItem(index, *i);
 812                 index++;
 813         }
 814         while(forcesize != -1 && index < forcesize){
 815                 invlist->deleteItem(index);
 816                 index++;
 817         }
 818 }
 819
 820 /******************************************************************************/
 821 ToolCapabilities read_tool_capabilities(
 822                 lua_State *L, int table)
 823 {
 824         ToolCapabilities toolcap;
 825         getfloatfield(L, table, "full_punch_interval", toolcap.full_punch_interval);
 826         getintfield(L, table, "max_drop_level", toolcap.max_drop_level);
 827         lua_getfield(L, table, "groupcaps");
 828         if(lua_istable(L, -1)){
 829                 int table_groupcaps = lua_gettop(L);
 830                 lua_pushnil(L);
 831                 while(lua_next(L, table_groupcaps) != 0){
 832                         // key at index -2 and value at index -1
 833                         std::string groupname = luaL_checkstring(L, -2);
 834                         if(lua_istable(L, -1)){
 835                                 int table_groupcap = lua_gettop(L);
 836                                 // This will be created
 837                                 ToolGroupCap groupcap;
 838                                 // Read simple parameters
 839                                 getintfield(L, table_groupcap, "maxlevel", groupcap.maxlevel);
 840                                 getintfield(L, table_groupcap, "uses", groupcap.uses);
 841                                 // DEPRECATED: maxwear
 842                                 float maxwear = 0;
 843                                 if(getfloatfield(L, table_groupcap, "maxwear", maxwear)){
 844                                         if(maxwear != 0)
 845                                                 groupcap.uses = 1.0/maxwear;
 846                                         else
 847                                                 groupcap.uses = 0;
 848                                         infostream<<script_get_backtrace(L)<<std::endl;
 849                                         infostream<<"WARNING: field \"maxwear\" is deprecated; "
 850                                                         <<"should replace with uses=1/maxwear"<<std::endl;
 851                                 }
 852                                 // Read "times" table
 853                                 lua_getfield(L, table_groupcap, "times");
 854                                 if(lua_istable(L, -1)){
 855                                         int table_times = lua_gettop(L);
 856                                         lua_pushnil(L);
 857                                         while(lua_next(L, table_times) != 0){
 858                                                 // key at index -2 and value at index -1
 859                                                 int rating = luaL_checkinteger(L, -2);
 860                                                 float time = luaL_checknumber(L, -1);
 861                                                 groupcap.times[rating] = time;
 862                                                 // removes value, keeps key for next iteration
 863                                                 lua_pop(L, 1);
 864                                         }
 865                                 }
 866                                 lua_pop(L, 1);
 867                                 // Insert groupcap into toolcap
 868                                 toolcap.groupcaps[groupname] = groupcap;
 869                         }
 870                         // removes value, keeps key for next iteration
 871                         lua_pop(L, 1);
 872                 }
 873         }
 874         lua_pop(L, 1);
 875
 876         lua_getfield(L, table, "damage_groups");
 877         if(lua_istable(L, -1)){
 878                 int table_damage_groups = lua_gettop(L);
 879                 lua_pushnil(L);
 880                 while(lua_next(L, table_damage_groups) != 0){
 881                         // key at index -2 and value at index -1
 882                         std::string groupname = luaL_checkstring(L, -2);
 883                         u16 value = luaL_checkinteger(L, -1);
 884                         toolcap.damageGroups[groupname] = value;
 885                         // removes value, keeps key for next iteration
 886                         lua_pop(L, 1);
 887                 }
 888         }
 889         lua_pop(L, 1);
 890         return toolcap;
 891 }
 892
 893 /******************************************************************************/
 894 void push_dig_params(lua_State *L,const DigParams &params)
 895 {
 896         lua_newtable(L);
 897         setboolfield(L, -1, "diggable", params.diggable);
 898         setfloatfield(L, -1, "time", params.time);
 899         setintfield(L, -1, "wear", params.wear);
 900 }
 901
 902 /******************************************************************************/
 903 void push_hit_params(lua_State *L,const HitParams &params)
 904 {
 905         lua_newtable(L);
 906         setintfield(L, -1, "hp", params.hp);
 907         setintfield(L, -1, "wear", params.wear);
 908 }
 909
 910 /******************************************************************************/
 911
 912 bool getflagsfield(lua_State *L, int table, const char *fieldname,
 913         FlagDesc *flagdesc, u32 *flags, u32 *flagmask)
 914 {
 915         lua_getfield(L, table, fieldname);
 916
 917         bool success = read_flags(L, -1, flagdesc, flags, flagmask);
 918
 919         lua_pop(L, 1);
 920
 921         return success;
 922 }
 923
 924 bool read_flags(lua_State *L, int index, FlagDesc *flagdesc,
 925         u32 *flags, u32 *flagmask)
 926 {
 927         if (lua_isstring(L, index)) {
 928                 std::string flagstr = lua_tostring(L, index);
 929                 *flags = readFlagString(flagstr, flagdesc, flagmask);
 930         } else if (lua_istable(L, index)) {
 931                 *flags = read_flags_table(L, index, flagdesc, flagmask);
 932         } else {
 933                 return false;
 934         }
 935
 936         return true;
 937 }
 938
 939 u32 read_flags_table(lua_State *L, int table, FlagDesc *flagdesc, u32 *flagmask)
 940 {
 941         u32 flags = 0, mask = 0;
 942         char fnamebuf[64] = "no";
 943
 944         for (int i = 0; flagdesc[i].name; i++) {
 945                 bool result;
 946
 947                 if (getboolfield(L, table, flagdesc[i].name, result)) {
 948                         mask |= flagdesc[i].flag;
 949                         if (result)
 950                                 flags |= flagdesc[i].flag;
 951                 }
 952
 953                 strlcpy(fnamebuf + 2, flagdesc[i].name, sizeof(fnamebuf) - 2);
 954                 if (getboolfield(L, table, fnamebuf, result))
 955                         mask |= flagdesc[i].flag;
 956         }
 957
 958         if (flagmask)
 959                 *flagmask = mask;
 960
 961         return flags;
 962 }
 963
 964 void push_flags_string(lua_State *L, FlagDesc *flagdesc, u32 flags, u32 flagmask)
 965 {
 966         std::string flagstring = writeFlagString(flags, flagdesc, flagmask);
 967         lua_pushlstring(L, flagstring.c_str(), flagstring.size());
 968 }
 969
 970 /******************************************************************************/
 971 /* Lua Stored data!                                                           */
 972 /******************************************************************************/
 973
 974 /******************************************************************************/
 975 void read_groups(lua_State *L, int index,
 976                 std::map<std::string, int> &result)
 977 {
 978         if (!lua_istable(L,index))
 979                 return;
 980         result.clear();
 981         lua_pushnil(L);
 982         if(index < 0)
 983                 index -= 1;
 984         while(lua_next(L, index) != 0){
 985                 // key at index -2 and value at index -1
 986                 std::string name = luaL_checkstring(L, -2);
 987                 int rating = luaL_checkinteger(L, -1);
 988                 result[name] = rating;
 989                 // removes value, keeps key for next iteration
 990                 lua_pop(L, 1);
 991         }
 992 }
 993
 994 /******************************************************************************/
 995 void push_groups(lua_State *L, const std::map<std::string, int> &groups)
 996 {
 997         lua_newtable(L);
 998         std::map<std::string, int>::const_iterator it;
 999         for (it = groups.begin(); it != groups.end(); ++it) {
1000                 lua_pushnumber(L, it->second);
1001                 lua_setfield(L, -2, it->first.c_str());
1002         }
1003 }
1004
1005 /******************************************************************************/
1006 void push_items(lua_State *L, const std::vector<ItemStack> &items)
1007 {
1008         lua_createtable(L, items.size(), 0);
1009         for (u32 i = 0; i != items.size(); i++) {
1010                 LuaItemStack::create(L, items[i]);
1011                 lua_rawseti(L, -2, i + 1);
1012         }
1013 }
1014
1015 /******************************************************************************/
1016 std::vector<ItemStack> read_items(lua_State *L, int index, Server *srv)
1017 {
1018         if(index < 0)
1019                 index = lua_gettop(L) + 1 + index;
1020
1021         std::vector<ItemStack> items;
1022         luaL_checktype(L, index, LUA_TTABLE);
1023         lua_pushnil(L);
1024         while (lua_next(L, index)) {
1025                 s32 key = luaL_checkinteger(L, -2);
1026                 if (key < 1) {
1027                         throw LuaError("Invalid inventory list index");
1028                 }
1029                 if (items.size() < (u32) key) {
1030                         items.resize(key);
1031                 }
1032                 items[key - 1] = read_item(L, -1, srv);
1033                 lua_pop(L, 1);
1034         }
1035         return items;
1036 }
1037
1038 /******************************************************************************/
1039 void luaentity_get(lua_State *L, u16 id)
1040 {
1041         // Get luaentities[i]
1042         lua_getglobal(L, "core");
1043         lua_getfield(L, -1, "luaentities");
1044         luaL_checktype(L, -1, LUA_TTABLE);
1045         lua_pushnumber(L, id);
1046         lua_gettable(L, -2);
1047         lua_remove(L, -2); // Remove luaentities
1048         lua_remove(L, -2); // Remove core
1049 }
1050
1051 /******************************************************************************/
1052 bool read_noiseparams(lua_State *L, int index, NoiseParams *np)
1053 {
1054         if (index < 0)
1055                 index = lua_gettop(L) + 1 + index;
1056
1057         if (!lua_istable(L, index))
1058                 return false;
1059
1060         getfloatfield(L, index, "offset",      np->offset);
1061         getfloatfield(L, index, "scale",       np->scale);
1062         getfloatfield(L, index, "persist",     np->persist);
1063         getfloatfield(L, index, "persistence", np->persist);
1064         getfloatfield(L, index, "lacunarity",  np->lacunarity);
1065         getintfield(L,   index, "seed",        np->seed);
1066         getintfield(L,   index, "octaves",     np->octaves);
1067
1068         u32 flags    = 0;
1069         u32 flagmask = 0;
1070         np->flags = getflagsfield(L, index, "flags", flagdesc_noiseparams,
1071                 &flags, &flagmask) ? flags : NOISE_FLAG_DEFAULTS;
1072
1073         lua_getfield(L, index, "spread");
1074         np->spread  = read_v3f(L, -1);
1075         lua_pop(L, 1);
1076
1077         return true;
1078 }
1079
1080 void push_noiseparams(lua_State *L, NoiseParams *np)
1081 {
1082         lua_newtable(L);
1083         lua_pushnumber(L, np->offset);
1084         lua_setfield(L, -2, "offset");
1085         lua_pushnumber(L, np->scale);
1086         lua_setfield(L, -2, "scale");
1087         lua_pushnumber(L, np->persist);
1088         lua_setfield(L, -2, "persistence");
1089         lua_pushnumber(L, np->lacunarity);
1090         lua_setfield(L, -2, "lacunarity");
1091         lua_pushnumber(L, np->seed);
1092         lua_setfield(L, -2, "seed");
1093         lua_pushnumber(L, np->octaves);
1094         lua_setfield(L, -2, "octaves");
1095
1096         push_flags_string(L, flagdesc_noiseparams, np->flags,
1097                 np->flags);
1098         lua_setfield(L, -2, "flags");
1099
1100         push_v3f(L, np->spread);
1101         lua_setfield(L, -2, "spread");
1102 }
1103
1104 /******************************************************************************/
1105 // Returns depth of json value tree
1106 static int push_json_value_getdepth(const Json::Value &value)
1107 {
1108         if (!value.isArray() && !value.isObject())
1109                 return 1;
1110
1111         int maxdepth = 0;
1112         for (Json::Value::const_iterator it = value.begin();
1113                         it != value.end(); ++it) {
1114                 int elemdepth = push_json_value_getdepth(*it);
1115                 if (elemdepth > maxdepth)
1116                         maxdepth = elemdepth;
1117         }
1118         return maxdepth + 1;
1119 }
1120 // Recursive function to convert JSON --> Lua table
1121 static bool push_json_value_helper(lua_State *L, const Json::Value &value,
1122                 int nullindex)
1123 {
1124         switch(value.type()) {
1125                 case Json::nullValue:
1126                 default:
1127                         lua_pushvalue(L, nullindex);
1128                         break;
1129                 case Json::intValue:
1130                         lua_pushinteger(L, value.asInt());
1131                         break;
1132                 case Json::uintValue:
1133                         lua_pushinteger(L, value.asUInt());
1134                         break;
1135                 case Json::realValue:
1136                         lua_pushnumber(L, value.asDouble());
1137                         break;
1138                 case Json::stringValue:
1139                         {
1140                                 const char *str = value.asCString();
1141                                 lua_pushstring(L, str ? str : "");
1142                         }
1143                         break;
1144                 case Json::booleanValue:
1145                         lua_pushboolean(L, value.asInt());
1146                         break;
1147                 case Json::arrayValue:
1148                         lua_newtable(L);
1149                         for (Json::Value::const_iterator it = value.begin();
1150                                         it != value.end(); ++it) {
1151                                 push_json_value_helper(L, *it, nullindex);
1152                                 lua_rawseti(L, -2, it.index() + 1);
1153                         }
1154                         break;
1155                 case Json::objectValue:
1156                         lua_newtable(L);
1157                         for (Json::Value::const_iterator it = value.begin();
1158                                         it != value.end(); ++it) {
1159                                 const char *str = it.memberName();
1160                                 lua_pushstring(L, str ? str : "");
1161                                 push_json_value_helper(L, *it, nullindex);
1162                                 lua_rawset(L, -3);
1163                         }
1164                         break;
1165         }
1166         return true;
1167 }
1168 // converts JSON --> Lua table; returns false if lua stack limit exceeded
1169 // nullindex: Lua stack index of value to use in place of JSON null
1170 bool push_json_value(lua_State *L, const Json::Value &value, int nullindex)
1171 {
1172         if(nullindex < 0)
1173                 nullindex = lua_gettop(L) + 1 + nullindex;
1174
1175         int depth = push_json_value_getdepth(value);
1176
1177         // The maximum number of Lua stack slots used at each recursion level
1178         // of push_json_value_helper is 2, so make sure there a depth * 2 slots
1179         if (lua_checkstack(L, depth * 2))
1180                 return push_json_value_helper(L, value, nullindex);
1181         else
1182                 return false;
1183 }
1184
1185 // Converts Lua table --> JSON
1186 void read_json_value(lua_State *L, Json::Value &root, int index, u8 recursion)
1187 {
1188         if (recursion > 16) {
1189                 throw SerializationError("Maximum recursion depth exceeded");
1190         }
1191         int type = lua_type(L, index);
1192         if (type == LUA_TBOOLEAN) {
1193                 root = (bool) lua_toboolean(L, index);
1194         } else if (type == LUA_TNUMBER) {
1195                 root = lua_tonumber(L, index);
1196         } else if (type == LUA_TSTRING) {
1197                 size_t len;
1198                 const char *str = lua_tolstring(L, index, &len);
1199                 root = std::string(str, len);
1200         } else if (type == LUA_TTABLE) {
1201                 lua_pushnil(L);
1202                 while (lua_next(L, index)) {
1203                         // Key is at -2 and value is at -1
1204                         Json::Value value;
1205                         read_json_value(L, value, lua_gettop(L), recursion + 1);
1206
1207                         Json::ValueType roottype = root.type();
1208                         int keytype = lua_type(L, -1);
1209                         if (keytype == LUA_TNUMBER) {
1210                                 lua_Number key = lua_tonumber(L, -1);
1211                                 if (roottype != Json::nullValue && roottype != Json::arrayValue) {
1212                                         throw SerializationError("Can't mix array and object values in JSON");
1213                                 } else if (key < 1) {
1214                                         throw SerializationError("Can't use zero-based or negative indexes in JSON");
1215                                 } else if (floor(key) != key) {
1216                                         throw SerializationError("Can't use indexes with a fractional part in JSON");
1217                                 }
1218                                 root[(Json::ArrayIndex) key - 1] = value;
1219                         } else if (keytype == LUA_TSTRING) {
1220                                 if (roottype != Json::nullValue && roottype != Json::objectValue) {
1221                                         throw SerializationError("Can't mix array and object values in JSON");
1222                                 }
1223                                 root[lua_tostring(L, -1)] = value;
1224                         } else {
1225                                 throw SerializationError("Lua key to convert to JSON is not a string or number");
1226                         }
1227                 }
1228         } else if (type == LUA_TNIL) {
1229                 root = Json::nullValue;
1230         } else {
1231                 throw SerializationError("Can only store booleans, numbers, strings, objects, arrays, and null in JSON");
1232         }
1233         lua_pop(L, 1); // Pop value
1234 }
1235