src/loader/Interpreter.cpp

   1 #include "Interpreter.h"
   2
   3 #include "ParsedSource.h"
   4 #include "TypeDescription.h"
   5 #include "../battle/Hero.h"
   6 #include "../battle/Monster.h"
   7 #include "../battle/PartyLayout.h"
   8 #include "../battle/Resources.h"
   9 #include "../common/Ikari.h"
  10 #include "../common/Item.h"
  11 #include "../common/Script.h"
  12 #include "../common/Spell.h"
  13 #include "../common/Stats.h"
  14 #include "../common/TargetingMode.h"
  15 #include "../graphics/ComplexAnimation.h"
  16 #include "../graphics/Font.h"
  17 #include "../graphics/Frame.h"
  18 #include "../graphics/Gauge.h"
  19 #include "../graphics/Menu.h"
  20 #include "../graphics/SimpleAnimation.h"
  21 #include "../graphics/Sprite.h"
  22
  23 #include <algorithm>
  24 #include <cstring>
  25 #include <SDL_image.h>
  26
  27 using battle::Hero;
  28 using battle::Monster;
  29 using battle::PartyLayout;
  30 using common::Ikari;
  31 using common::Item;
  32 using common::Script;
  33 using common::Spell;
  34 using common::Stats;
  35 using common::TargetingMode;
  36 using graphics::Animation;
  37 using graphics::Color;
  38 using graphics::Font;
  39 using graphics::Frame;
  40 using graphics::Gauge;
  41 using graphics::ComplexAnimation;
  42 using graphics::SimpleAnimation;
  43 using graphics::Sprite;
  44 using math::Vector;
  45 using std::make_pair;
  46 using std::set;
  47 using std::string;
  48 using std::vector;
  49
  50 namespace loader {
  51
  52 Interpreter::~Interpreter() {
  53         for (std::map<string, SDL_Surface *>::const_iterator i(imageCache.begin()), end(imageCache.end()); i != end; ++i) {
  54                 SDL_FreeSurface(i->second);
  55         }
  56 }
  57
  58
  59 const Interpreter::ParsedDefinition &Interpreter::GetDefinition(const string &identifier) {
  60         std::map<string, ParsedDefinition>::const_iterator i(parsedDefinitions.find(identifier));
  61         if (i != parsedDefinitions.end()) {
  62                 return i->second;
  63         } else if (source.IsDefined(identifier)) {
  64                 ReadDefinition(source.GetDefinition(identifier));
  65                 return parsedDefinitions.at(identifier);
  66         } else {
  67                 throw Error("access to undefined object " + identifier);
  68         }
  69 }
  70
  71 const Interpreter::ParsedDefinition &Interpreter::GetDefinition(const string &identifier) const {
  72         std::map<string, ParsedDefinition>::const_iterator i(parsedDefinitions.find(identifier));
  73         if (i != parsedDefinitions.end()) {
  74                 return i->second;
  75         } else {
  76                 throw Error("access to undefined object " + identifier);
  77         }
  78 }
  79
  80
  81 void *Interpreter::GetObject(
  82                 int typeId,
  83                 const std::string &name) {
  84         std::map<string, ParsedDefinition>::const_iterator
  85                         i(parsedDefinitions.find(name));
  86         if (i != parsedDefinitions.end()) {
  87                 const TypeDescription &requested =
  88                                 TypeDescription::Get(typeId);
  89                 const TypeDescription &actual =
  90                                 TypeDescription::Get(i->second.type);
  91                 if (requested.TypeId() == actual.TypeId()) {
  92                         return values[actual.TypeId()][i->second.id];
  93                 } else if (actual.IsSubtypeOf(requested)) {
  94                         char *sub = reinterpret_cast<char *>(
  95                                         values[actual.TypeId()][i->second.id]);
  96                         std::ptrdiff_t offset =
  97                                         actual.SupertypeOffset(requested);
  98                         return sub - offset;
  99                 } else {
 100                         throw Error("cannot cast " + actual.TypeName()
 101                                         + " to " + requested.TypeName());
 102                 }
 103         } else {
 104                 throw Error("access to undefined object " + name);
 105         }
 106 }
 107
 108 const void *Interpreter::GetObject(
 109                 int typeId,
 110                 const std::string &name) const {
 111         std::map<string, ParsedDefinition>::const_iterator
 112                         i(parsedDefinitions.find(name));
 113         if (i != parsedDefinitions.end()) {
 114                 const TypeDescription &requested =
 115                                 TypeDescription::Get(typeId);
 116                 const TypeDescription &actual =
 117                                 TypeDescription::Get(i->second.type);
 118                 if (requested.TypeId() == actual.TypeId()) {
 119                         return values.at(actual.TypeId()).at(i->second.id);
 120                 } else if (actual.IsSubtypeOf(requested)) {
 121                         char *sub = reinterpret_cast<char *>(
 122                                         values.at(actual.TypeId()).at(i->second.id));
 123                         std::ptrdiff_t offset =
 124                                         actual.SupertypeOffset(requested);
 125                         return sub - offset;
 126                 } else {
 127                         throw Error("cannot cast " + actual.TypeName()
 128                                         + " to " + requested.TypeName());
 129                 }
 130         } else {
 131                 throw Error("access to undefined object " + name);
 132         }
 133 }
 134
 135
 136 void Interpreter::ReadSource() {
 137         for (set<string>::const_iterator i(source.Exports().begin()), end(source.Exports().end()); i != end; ++i) {
 138                 ReadDefinition(source.GetDefinition(*i));
 139         }
 140 }
 141
 142 void Interpreter::ReadDefinition(const Definition &dfn) {
 143         if (parsedDefinitions.find(dfn.Identifier()) != parsedDefinitions.end()) {
 144                 return;
 145         }
 146         if (dfn.HasLiteralValue()) {
 147                 ReadLiteral(dfn);
 148         } else {
 149                 ReadObject(dfn);
 150         }
 151 }
 152
 153 void Interpreter::ReadLiteral(const Definition &dfn) {
 154         const string &typeName(dfn.GetLiteral()->IsArray() ? "Array" : dfn.GetLiteral()->GetTypeName());
 155         int typeId(TypeDescription::GetTypeId(typeName));
 156         int id(values[typeId].size());
 157         const TypeDescription &td(TypeDescription::Get(typeId));
 158         int size(
 159                         (dfn.GetLiteral()->GetType() == Literal::PATH
 160                                         || dfn.GetLiteral()->GetType() == Literal::STRING)
 161                         ? dfn.GetLiteral()->GetString().size() : td.Size());
 162         char *object(alloc.Alloc(size));
 163         values[typeId].push_back(object);
 164         parsedDefinitions.insert(make_pair(dfn.Identifier(), ParsedDefinition(&dfn, typeId, id)));
 165         if (dfn.GetLiteral()->GetType() == Literal::OBJECT) {
 166                 ReadObject(typeId, id, object, *dfn.GetLiteral()->GetProperties());
 167         } else {
 168                 ReadLiteral(typeId, id, object, *dfn.GetLiteral());
 169         }
 170 }
 171
 172 void Interpreter::ReadLiteral(int typeId, int id, char *object, const Literal &literal) {
 173         switch (literal.GetType()) {
 174                 case Literal::ARRAY_VALUES:
 175                 case Literal::ARRAY_PROPS:
 176                 case Literal::ARRAY_IDENTS:
 177                         throw Error("named arrays are not supported, sorry");
 178                         break;
 179                 case Literal::BOOLEAN:
 180                         new (object) bool(literal.GetBoolean());
 181                         break;
 182                 case Literal::COLOR:
 183                         new (object) Color(literal.GetRed(), literal.GetGreen(), literal.GetBlue(), literal.GetAlpha());
 184                         break;
 185                 case Literal::NUMBER:
 186                         new (object) int(literal.GetNumber());
 187                         break;
 188                 case Literal::PATH:
 189                         std::memcpy(object, literal.GetString().c_str(), literal.GetString().size());
 190                         object[literal.GetString().size()] = '\0';
 191                         break;
 192                 case Literal::SCRIPT:
 193                         new (object) Script;
 194                         ReadScript(literal.GetScript(), reinterpret_cast<Script *>(object));
 195                         break;
 196                 case Literal::STRING:
 197                         std::memcpy(object, literal.GetString().c_str(), literal.GetString().size());
 198                         object[literal.GetString().size()] = '\0';
 199                         break;
 200                 case Literal::VECTOR:
 201                         new (object) Vector<int>(literal.GetX(), literal.GetY());
 202                         break;
 203                 case Literal::OBJECT:
 204                         throw Error("illogical branch: read literal object as non-object literal");
 205         }
 206 }
 207
 208
 209 void *Interpreter::GetObject(int typeId, const Value &v) {
 210         if (v.IsLiteral()) {
 211                 if (v.GetLiteral().IsObject()) {
 212                         int typeId(TypeDescription::GetTypeId(v.GetLiteral().GetTypeName()));
 213                         const TypeDescription &td(TypeDescription::Get(typeId));
 214                         char *object(alloc.Alloc(td.Size()));
 215                         td.Construct(object);
 216                         int id(values[typeId].size());
 217                         values[typeId].push_back(object);
 218                         ReadObject(typeId, id, object, *v.GetLiteral().GetProperties());
 219                         return object;
 220                 } else {
 221                         int typeId(0), id(0);
 222                         switch (v.GetLiteral().GetType()) {
 223                                 case Literal::ARRAY_VALUES:
 224                                 case Literal::ARRAY_PROPS:
 225                                 case Literal::ARRAY_IDENTS:
 226                                         throw Error("cannot copy arrays, sorry");
 227                                         break;
 228                                 case Literal::BOOLEAN:
 229                                         {
 230                                                 typeId = TypeDescription::GetTypeId("Boolean");
 231                                                 id = values[typeId].size();
 232                                                 const TypeDescription &td(TypeDescription::Get(typeId));
 233                                                 char *object(alloc.Alloc(td.Size()));
 234                                                 values[typeId].push_back(new (object) bool(v.GetLiteral().GetBoolean()));
 235                                         }
 236                                         break;
 237                                 case Literal::COLOR:
 238                                         {
 239                                                 typeId = TypeDescription::GetTypeId("Color");
 240                                                 id = values[typeId].size();
 241                                                 const TypeDescription &td(TypeDescription::Get(typeId));
 242                                                 char *object(alloc.Alloc(td.Size()));
 243                                                 values[typeId].push_back(new (object) Color(v.GetLiteral().GetRed(), v.GetLiteral().GetGreen(), v.GetLiteral().GetBlue(), v.GetLiteral().GetAlpha()));
 244                                         }
 245                                         break;
 246                                 case Literal::NUMBER:
 247                                         {
 248                                                 typeId = TypeDescription::GetTypeId("Number");
 249                                                 id = values[typeId].size();
 250                                                 const TypeDescription &td(TypeDescription::Get(typeId));
 251                                                 char *object(alloc.Alloc(td.Size()));
 252                                                 values[typeId].push_back(new (object) int(v.GetLiteral().GetNumber()));
 253                                         }
 254                                         break;
 255                                 case Literal::PATH:
 256                                         {
 257                                                 typeId = TypeDescription::GetTypeId("Path");
 258                                                 id = values[typeId].size();
 259                                                 char *str(alloc.Alloc(v.GetLiteral().GetString().size() + 1));
 260                                                 std::memcpy(str, v.GetLiteral().GetString().c_str(), v.GetLiteral().GetString().size());
 261                                                 str[v.GetLiteral().GetString().size()] = '\0';
 262                                                 values[typeId].push_back(str);
 263                                         }
 264                                         break;
 265                                 case Literal::SCRIPT:
 266                                         {
 267                                                 typeId = TypeDescription::GetTypeId("Script");
 268                                                 char *script(ReadScript(v.GetLiteral().GetScript()));
 269                                                 id = values[typeId].size();
 270                                                 values[typeId].push_back(script);
 271                                         }
 272                                         break;
 273                                 case Literal::STRING:
 274                                         {
 275                                                 typeId = TypeDescription::GetTypeId("String");
 276                                                 id = values[typeId].size();
 277                                                 char *str(alloc.Alloc(v.GetLiteral().GetString().size() + 1));
 278                                                 std::memcpy(str, v.GetLiteral().GetString().c_str(), v.GetLiteral().GetString().size());
 279                                                 str[v.GetLiteral().GetString().size()] = '\0';
 280                                                 values[typeId].push_back(str);
 281                                         }
 282                                         break;
 283                                 case Literal::VECTOR:
 284                                         {
 285                                                 typeId = TypeDescription::GetTypeId("Vector");
 286                                                 id = values[typeId].size();
 287                                                 const TypeDescription &td(TypeDescription::Get(typeId));
 288                                                 char *object(alloc.Alloc(td.Size()));
 289                                                 values[typeId].push_back(new (object) Vector<int>(v.GetLiteral().GetX(), v.GetLiteral().GetY()));
 290                                         }
 291                                         break;
 292                                 case Literal::OBJECT:
 293                                         {
 294                                                 typeId = TypeDescription::GetTypeId(v.GetLiteral().GetTypeName());
 295                                                 const TypeDescription &td(TypeDescription::Get(typeId));
 296                                                 id = values[typeId].size();
 297                                                 char *object(alloc.Alloc(td.Size()));
 298                                                 td.Construct(object);
 299                                                 ReadObject(typeId, id, object, *v.GetLiteral().GetProperties());
 300                                         }
 301                                         break;
 302                         }
 303                         return values[typeId][id];
 304                 }
 305         } else {
 306                 ReadDefinition(source.GetDefinition(v.GetIdentifier()));
 307                 return GetObject(typeId, v.GetIdentifier());
 308         }
 309 }
 310
 311
 312 void Interpreter::ReadObject(const Definition &dfn) {
 313         int typeId(TypeDescription::GetTypeId(dfn.TypeName()));
 314         const TypeDescription &td(TypeDescription::Get(typeId));
 315         int id(values[typeId].size());
 316         char *object(alloc.Alloc(td.Size()));
 317         td.Construct(object);
 318         values[typeId].push_back(object);
 319         parsedDefinitions.insert(make_pair(dfn.Identifier(), ParsedDefinition(&dfn, typeId, id)));
 320         ReadObject(typeId, id, object, *dfn.GetProperties());
 321 }
 322
 323
 324 void Interpreter::ReadObject(int typeId, int id, char *object, const PropertyList &props) {
 325         const TypeDescription &td(TypeDescription::Get(typeId));
 326         for (PropertyList::ConstIterator i(props.Begin()), end(props.End()); i != end; ++i) {
 327                 const FieldDescription &fd(td.GetField(i->first));
 328                 const TypeDescription &fieldType(TypeDescription::Get(fd.TypeId()));
 329                 if (CanLink(*i->second)) {
 330                         char *dest(object + fd.Offset());
 331                         if (fd.IsAggregate()) {
 332                                 int arraySize(i->second->GetLiteral().ArraySize());
 333                                 size_t memberSize = fd.IsReferenced() ? sizeof(char *) : fieldType.Size();
 334                                 Array array;
 335                                 array.size = arraySize * memberSize;
 336                                 array.data = alloc.Alloc(array.size);
 337                                 array.ref = fd.IsReferenced();
 338                                 arrays.push_back(array);
 339                                 char *iter = reinterpret_cast<char *>(array.data);
 340                                 if (i->second->GetLiteral().GetType() == Literal::ARRAY_PROPS) {
 341                                         const vector<PropertyList *> &list(i->second->GetLiteral().GetPropertyLists());
 342                                         for (vector<PropertyList *>::const_iterator
 343                                                         j(list.begin()), end(list.end());
 344                                                         j != end; ++j, iter += memberSize) {
 345                                                 char *member;
 346                                                 if (fd.IsReferenced()) {
 347                                                         member = alloc.Alloc(fieldType.Size());
 348                                                         *reinterpret_cast<char **>(iter) = member;
 349                                                 } else {
 350                                                         member = iter;
 351                                                 }
 352                                                 fieldType.Construct(member);
 353                                                 ReadObject(fieldType.TypeId(), -1, member, **j);
 354                                         }
 355                                 } else if (i->second->GetLiteral().GetType() == Literal::ARRAY_VALUES) {
 356                                         const vector<Value *> &list(i->second->GetLiteral().GetValues());
 357                                         for (vector<Value *>::const_iterator j(list.begin()), end(list.end());
 358                                                         j != end; ++j, iter += memberSize) {
 359                                                 char *member;
 360                                                 if (fd.IsReferenced()) {
 361                                                         member = alloc.Alloc(fieldType.Size());
 362                                                         *reinterpret_cast<char **>(iter) = member;
 363                                                 } else {
 364                                                         member = iter;
 365                                                 }
 366                                                 fieldType.Construct(member);
 367                                                 ReadLiteral(fieldType.TypeId(), -1, member, (*j)->GetLiteral());
 368                                         }
 369                                 } else {
 370                                         if (!fd.IsReferenced()) {
 371                                                 // TODO: implement inline identifier arrays
 372                                                 throw std::runtime_error("inline identifier arrays not implemented (yet)");
 373                                         }
 374                                         const vector<string> &list(i->second->GetLiteral().GetIdentifiers());
 375                                         for (vector<string>::const_iterator j(list.begin()), end(list.end());
 376                                                         j != end; ++j, iter += memberSize) {
 377                                                 if (source.IsDefined(*j)) {
 378                                                         *reinterpret_cast<void **>(iter)
 379                                                                         = GetObject(fd.TypeId(), *j);
 380                                                 } else {
 381                                                         Postpone(reinterpret_cast<char *>(array.data),
 382                                                                         iter, *j, fd.TypeId(), false);
 383                                                 }
 384                                         }
 385                                 }
 386                                 std::memcpy(dest, &array.data, sizeof(char *));
 387                                 dest += sizeof(char *);
 388                                 std::memcpy(dest, &arraySize, sizeof(int));
 389                         } else if (i->second->IsLiteral() && !fd.IsReferenced()) {
 390                                 // inline literals
 391                                 if (i->second->GetLiteral().IsObject()) {
 392                                         ReadObject(fd.TypeId(), -1, dest, *i->second->GetLiteral().GetProperties());
 393                                 } else {
 394                                         ReadLiteral(fd.TypeId(), -1, dest, i->second->GetLiteral());
 395                                 }
 396                         } else {
 397                                 char *src(reinterpret_cast<char *>(GetObject(fd.TypeId(), *i->second)));
 398                                 if (fd.TypeId() == TypeDescription::GetTypeId("Image")) {
 399                                         src = reinterpret_cast<char *>(GetImage(src));
 400                                 }
 401                                 if (fd.IsReferenced()) {
 402                                         std::memcpy(dest, &src, sizeof(char *));
 403                                 } else {
 404                                         std::memcpy(dest, src, fieldType.Size());
 405                                 }
 406                         }
 407                 } else {
 408                         Postpone(object, object + fd.Offset(), i->second->GetIdentifier(), fd.TypeId(), !fd.IsReferenced(), fd.IsAggregate());
 409                 }
 410         }
 411         td.Load(object);
 412 }
 413
 414
 415 void Interpreter::ReadScript(const std::vector<ScriptToken *> &s, Script *script) {
 416         std::map<string, int> labels;
 417         int size(0);
 418         for (vector<ScriptToken *>::const_iterator i(s.begin()), end(s.end()); i != end; ++i) {
 419                 if ((*i)->GetType() == ScriptToken::LABEL) {
 420                         if (labels.count((*i)->Label())) {
 421                                 throw Error("duplicate label " + (*i)->Label());
 422                         } else {
 423                                 labels[(*i)->Label()] = size;
 424                         }
 425                 } else if ((*i)->GetType() != ScriptToken::COMMAND) {
 426                         throw Error("unexpected script token");
 427                 }
 428                 size += sizeof(Script::Code);
 429                 const string &cmd((*i)->CommandName());
 430                 if (cmd == "move") {
 431                         ++i;
 432                         if (i == end) {
 433                                 throw Error("unexpected script end after move");
 434                         }
 435                         const string &reg((*i)->RegisterName());
 436                         if (reg.size() != 2) {
 437                                 throw Error("invalid register name " + reg);
 438                         }
 439                         ++i;
 440                         if (i == end) {
 441                                 throw Error("unexpected script end after move");
 442                         }
 443                         if ((*i)->GetType() != ScriptToken::REGISTER) {
 444                                 switch (reg[0]) {
 445                                         case 'a':
 446                                                 size += sizeof(void *);
 447                                                 break;
 448                                         case 'i':
 449                                                 size += sizeof(int);
 450                                                 break;
 451                                         case 'v':
 452                                                 size += sizeof(Vector<int>);
 453                                                 break;
 454                                         default:
 455                                                 throw Error("unknown register " + reg);
 456                                 }
 457                         }
 458                 } else if (cmd == "add") {
 459                         ++i;
 460                         if (i == end) {
 461                                 throw Error("unexpected script end after add");
 462                         }
 463                         const string &reg((*i)->RegisterName());
 464                         if (reg.size() != 2) {
 465                                 throw Error("invalid register name " + reg);
 466                         }
 467                         ++i;
 468                         if (i == end) {
 469                                 throw Error("unexpected script end after add");
 470                         }
 471                         if ((*i)->GetType() != ScriptToken::REGISTER) {
 472                                 switch (reg[0]) {
 473                                         case 'i':
 474                                                 size += sizeof(int);
 475                                                 break;
 476                                         case 'v':
 477                                                 size += sizeof(Vector<int>);
 478                                                 break;
 479                                         default:
 480                                                 throw Error("expected register after add " + reg);
 481                                 }
 482                         }
 483                 } else if (cmd == "mod") {
 484                         ++i;
 485                         if (i == end) {
 486                                 throw Error("unexpected script end after mod");
 487                         }
 488                         ++i;
 489                         if (i == end) {
 490                                 throw Error("unexpected script end after mod");
 491                         }
 492                         if ((*i)->GetType() != ScriptToken::REGISTER) {
 493                                 size += sizeof(int);
 494                         }
 495                 } else if (cmd == "rand") {
 496                         ++i;
 497                         if (i == end) {
 498                                 throw Error("unexpected script end after rand");
 499                         }
 500                 } else if (cmd == "cmp") {
 501                         ++i;
 502                         if (i == end) {
 503                                 throw Error("unexpected script end after cmp");
 504                         }
 505                         if ((*i)->GetType() != ScriptToken::REGISTER) {
 506                                 size += sizeof(int);
 507                         }
 508                         ++i;
 509                         if (i == end) {
 510                                 throw Error("unexpected script end after cmp");
 511                         }
 512                         if ((*i)->GetType() != ScriptToken::REGISTER) {
 513                                 size += sizeof(int);
 514                         }
 515                 } else if (cmd == "jmp") {
 516                         size += sizeof(int);
 517                         ++i;
 518                         if (i == end) {
 519                                 throw Error("unexpected script end after cmp");
 520                         }
 521                 } else if (cmd == "jeq") {
 522                         size += sizeof(int);
 523                         ++i;
 524                         if (i == end) {
 525                                 throw Error("unexpected script end after cmp");
 526                         }
 527                 } else if (cmd == "jne") {
 528                         size += sizeof(int);
 529                         ++i;
 530                         if (i == end) {
 531                                 throw Error("unexpected script end after cmp");
 532                         }
 533                 } else if (cmd == "jl") {
 534                         size += sizeof(int);
 535                         ++i;
 536                         if (i == end) {
 537                                 throw Error("unexpected script end after cmp");
 538                         }
 539                 } else if (cmd == "jle") {
 540                         size += sizeof(int);
 541                         ++i;
 542                         if (i == end) {
 543                                 throw Error("unexpected script end after cmp");
 544                         }
 545                 } else if (cmd == "jg") {
 546                         size += sizeof(int);
 547                         ++i;
 548                         if (i == end) {
 549                                 throw Error("unexpected script end after cmp");
 550                         }
 551                 } else if (cmd == "jge") {
 552                         size += sizeof(int);
 553                         ++i;
 554                         if (i == end) {
 555                                 throw Error("unexpected script end after cmp");
 556                         }
 557                 } else if (cmd == "sysc") {
 558
 559                 } else {
 560                         throw Error("unknown command " + cmd);
 561                 }
 562         }
 563
 564         char *text(alloc.Alloc(size));
 565         int cursor(0);
 566         for (vector<ScriptToken *>::const_iterator i(s.begin()), end(s.end()); i != end; ++i) {
 567                 if ((*i)->GetType() == ScriptToken::LABEL) {
 568                         continue;
 569                 }
 570                 if ((*i)->GetType() != ScriptToken::COMMAND) {
 571                         throw Error("unexpected script token");
 572                 }
 573                 const string &cmd((*i)->CommandName());
 574                 if (cmd == "move") {
 575                         Script::Code &code(CreateScriptCode(Script::COMMAND_MOVE, text + cursor));
 576                         cursor += sizeof(Script::Code);
 577                         code.numParams = 2;
 578                         ++i;
 579                         const string &reg((*i)->RegisterName());
 580                         switch (reg[0]) {
 581                                 case 'a':
 582                                         code.type = Script::TYPE_ADDRESS;
 583                                         break;
 584                                 case 'i':
 585                                         code.type = Script::TYPE_INTEGER;
 586                                         break;
 587                                 case 'v':
 588                                         code.type = Script::TYPE_VECTOR;
 589                                         break;
 590                                 default:
 591                                         throw Error("invalid register " + reg);
 592                         }
 593                         int regnum(reg[1] - '0');
 594                         if (regnum < 0 || regnum > 6) {
 595                                 throw Error("invalid register " + reg);
 596                         }
 597                         code.reg1 = regnum;
 598                         ++i;
 599
 600                         if ((*i)->GetType() == ScriptToken::REGISTER) {
 601                                 string reg2((*i)->RegisterName());
 602                                 if (reg[0] != reg2[0]) {
 603                                         throw Error("mixed-type commands not allowed");
 604                                 }
 605                                 int reg2num(reg[1] - '0');
 606                                 if (reg2num < 0 || reg2num > 6) {
 607                                         throw Error("invalid register " + reg2);
 608                                 }
 609                                 code.reg2 = reg2num;
 610                         } else {
 611                                 code.reg2 = 7;
 612                                 switch (code.type) {
 613                                         case Script::TYPE_ADDRESS:
 614                                                 ReadScriptAddress(**i, text + cursor);
 615                                                 cursor += sizeof(void *);
 616                                                 break;
 617                                         case Script::TYPE_INTEGER:
 618                                                 ReadScriptInteger(**i, text + cursor);
 619                                                 cursor += sizeof(int);
 620                                                 break;
 621                                         case Script::TYPE_VECTOR:
 622                                                 ReadScriptVector(**i, text + cursor);
 623                                                 cursor += sizeof(Vector<int>);
 624                                                 break;
 625                                 }
 626                         }
 627                 } else if (cmd == "add") {
 628                         Script::Code &code(CreateScriptCode(Script::COMMAND_ADD, text + cursor));
 629                         cursor += sizeof(Script::Code);
 630                         code.numParams = 2;
 631                         ++i;
 632                         const string &reg((*i)->RegisterName());
 633                         switch (reg[0]) {
 634                                 case 'i':
 635                                         code.type = Script::TYPE_INTEGER;
 636                                         break;
 637                                 case 'v':
 638                                         code.type = Script::TYPE_VECTOR;
 639                                         break;
 640                                 default:
 641                                         throw Error("invalid register " + reg);
 642                         }
 643                         int regnum(reg[1] - '0');
 644                         if (regnum < 0 || regnum > 6) {
 645                                 throw Error("invalid register " + reg);
 646                         }
 647                         code.reg1 = regnum;
 648                         ++i;
 649
 650                         if ((*i)->GetType() == ScriptToken::REGISTER) {
 651                                 string reg2((*i)->RegisterName());
 652                                 if (reg[0] != reg2[0]) {
 653                                         throw Error("mixed-type commands not allowed");
 654                                 }
 655                                 int reg2num(reg[1] - '0');
 656                                 if (reg2num < 0 || reg2num > 6) {
 657                                         throw Error("invalid register name " + reg2);
 658                                 }
 659                                 code.reg2 = reg2num;
 660                         } else {
 661                                 code.reg2 = 7;
 662                                 switch (code.type) {
 663                                         case Script::TYPE_INTEGER:
 664                                                 ReadScriptInteger(**i, text + cursor);
 665                                                 cursor += sizeof(int);
 666                                                 break;
 667                                         case Script::TYPE_VECTOR:
 668                                                 ReadScriptVector(**i, text + cursor);
 669                                                 cursor += sizeof(Vector<int>);
 670                                                 break;
 671                                 }
 672                         }
 673                 } else if (cmd == "mod") {
 674                         Script::Code &code(CreateScriptCode(Script::COMMAND_MOD, text + cursor));
 675                         cursor += sizeof(Script::Code);
 676                         code.numParams = 2;
 677                         ++i;
 678                         const string &reg((*i)->RegisterName());
 679                         if (reg[0] != 'i') {
 680                                 throw Error("invalid register " + reg);
 681                         }
 682                         code.type = Script::TYPE_INTEGER;
 683                         int regnum(reg[1] - '0');
 684                         if (regnum < 0 || regnum > 6) {
 685                                 throw Error("invalid register " + reg);
 686                         }
 687                         code.reg1 = regnum;
 688                         ++i;
 689
 690                         if ((*i)->GetType() == ScriptToken::REGISTER) {
 691                                 string reg2((*i)->RegisterName());
 692                                 if (reg[0] != reg2[0]) {
 693                                         throw Error("mixed-type commands not allowed");
 694                                 }
 695                                 int reg2num(reg[1] - '0');
 696                                 if (reg2num < 0 || reg2num > 6) {
 697                                         throw Error("invalid register name " + reg2);
 698                                 }
 699                                 code.reg2 = reg2num;
 700                         } else {
 701                                 code.reg2 = 7;
 702                                 ReadScriptInteger(**i, text + cursor);
 703                                 cursor += sizeof(int);
 704                         }
 705                 } else if (cmd == "rand") {
 706                         Script::Code &code(CreateScriptCode(Script::COMMAND_RAND, text + cursor));
 707                         cursor += sizeof(Script::Code);
 708                         code.numParams = 1;
 709                         ++i;
 710                         const string &reg((*i)->RegisterName());
 711                         if (reg[0] != 'i') {
 712                                 throw Error("invalid register " + reg);
 713                         }
 714                         code.type = Script::TYPE_INTEGER;
 715                         int regnum(reg[1] - '0');
 716                         if (regnum < 0 || regnum > 6) {
 717                                 throw Error("invalid register " + reg);
 718                         }
 719                         code.reg1 = regnum;
 720                 } else if (cmd == "cmp") {
 721                         Script::Code &code(CreateScriptCode(Script::COMMAND_CMP, text + cursor));
 722                         cursor += sizeof(Script::Code);
 723                         code.numParams = 2;
 724                         ++i;
 725                         const string &reg((*i)->RegisterName());
 726                         if (reg[0] != 'i') {
 727                                 throw Error("invalid register " + reg);
 728                         }
 729                         code.type = Script::TYPE_INTEGER;
 730                         int regnum(reg[1] - '0');
 731                         if (regnum < 0 || regnum > 6) {
 732                                 throw Error("invalid register " + reg);
 733                         }
 734                         code.reg1 = regnum;
 735                         ++i;
 736
 737                         if ((*i)->GetType() == ScriptToken::REGISTER) {
 738                                 string reg2((*i)->RegisterName());
 739                                 if (reg[0] != reg2[0]) {
 740                                         throw Error("mixed-type commands not allowed");
 741                                 }
 742                                 int reg2num(reg[1] - '0');
 743                                 if (reg2num < 0 || reg2num > 6) {
 744                                         throw Error("invalid register name " + reg2);
 745                                 }
 746                                 code.reg2 = reg2num;
 747                         } else {
 748                                 code.reg2 = 7;
 749                                 ReadScriptInteger(**i, text + cursor);
 750                                 cursor += sizeof(int);
 751                         }
 752                 } else if (cmd == "jmp") {
 753                         Script::Code &code(CreateScriptCode(Script::COMMAND_JMP, text + cursor));
 754                         cursor += sizeof(Script::Code);
 755                         code.numParams = 1;
 756                         ++i;
 757                         if (!labels.count((*i)->Identifier())) {
 758                                 throw Error("use of undefined label " + (*i)->Identifier());
 759                         }
 760                         *reinterpret_cast<int *>(text + cursor) = labels[(*i)->Identifier()];
 761                         cursor += sizeof(int);
 762                 } else if (cmd == "jeq") {
 763                         Script::Code &code(CreateScriptCode(Script::COMMAND_JEQ, text + cursor));
 764                         cursor += sizeof(Script::Code);
 765                         code.numParams = 1;
 766                         ++i;
 767                         if (!labels.count((*i)->Identifier())) {
 768                                 throw Error("use of undefined label " + (*i)->Identifier());
 769                         }
 770                         *reinterpret_cast<int *>(text + cursor) = labels[(*i)->Identifier()];
 771                         cursor += sizeof(int);
 772                 } else if (cmd == "jne") {
 773                         Script::Code &code(CreateScriptCode(Script::COMMAND_JNE, text + cursor));
 774                         cursor += sizeof(Script::Code);
 775                         code.numParams = 1;
 776                         ++i;
 777                         if (!labels.count((*i)->Identifier())) {
 778                                 throw Error("use of undefined label " + (*i)->Identifier());
 779                         }
 780                         *reinterpret_cast<int *>(text + cursor) = labels[(*i)->Identifier()];
 781                         cursor += sizeof(int);
 782                 } else if (cmd == "jl") {
 783                         Script::Code &code(CreateScriptCode(Script::COMMAND_JL, text + cursor));
 784                         cursor += sizeof(Script::Code);
 785                         code.numParams = 1;
 786                         ++i;
 787                         if (!labels.count((*i)->Identifier())) {
 788                                 throw Error("use of undefined label " + (*i)->Identifier());
 789                         }
 790                         *reinterpret_cast<int *>(text + cursor) = labels[(*i)->Identifier()];
 791                         cursor += sizeof(int);
 792                 } else if (cmd == "jle") {
 793                         Script::Code &code(CreateScriptCode(Script::COMMAND_JLE, text + cursor));
 794                         cursor += sizeof(Script::Code);
 795                         code.numParams = 1;
 796                         ++i;
 797                         if (!labels.count((*i)->Identifier())) {
 798                                 throw Error("use of undefined label " + (*i)->Identifier());
 799                         }
 800                         *reinterpret_cast<int *>(text + cursor) = labels[(*i)->Identifier()];
 801                         cursor += sizeof(int);
 802                 } else if (cmd == "jg") {
 803                         Script::Code &code(CreateScriptCode(Script::COMMAND_JG, text + cursor));
 804                         cursor += sizeof(Script::Code);
 805                         code.numParams = 1;
 806                         ++i;
 807                         if (!labels.count((*i)->Identifier())) {
 808                                 throw Error("use of undefined label " + (*i)->Identifier());
 809                         }
 810                         *reinterpret_cast<int *>(text + cursor) = labels[(*i)->Identifier()];
 811                         cursor += sizeof(int);
 812                 } else if (cmd == "jge") {
 813                         Script::Code &code(CreateScriptCode(Script::COMMAND_JGE, text + cursor));
 814                         cursor += sizeof(Script::Code);
 815                         code.numParams = 1;
 816                         ++i;
 817                         if (!labels.count((*i)->Identifier())) {
 818                                 throw Error("use of undefined label " + (*i)->Identifier());
 819                         }
 820                         *reinterpret_cast<int *>(text + cursor) = labels[(*i)->Identifier()];
 821                         cursor += sizeof(int);
 822                 } else if (cmd == "sysc") {
 823                         Script::Code &code(CreateScriptCode(Script::COMMAND_SYSC, text + cursor));
 824                         cursor += sizeof(Script::Code);
 825                         code.numParams = 0;
 826                 } else {
 827                         throw Error("unknown command " + cmd);
 828                 }
 829         }
 830
 831         script->text = text;
 832         script->textlen = size;
 833 }
 834
 835 char *Interpreter::ReadScript(const vector<ScriptToken *> &s) {
 836         char *mem(alloc.Alloc(sizeof(Script)));
 837         new (mem) Script;
 838         Script *script(reinterpret_cast<Script *>(mem));
 839         ReadScript(s, script);
 840         return mem;
 841 }
 842
 843 Script::Code &Interpreter::CreateScriptCode(Script::Command c, char *dest) {
 844         Script::Code &code(*reinterpret_cast<Script::Code *>(dest));
 845         code.command = c;
 846         code.numParams = 0;
 847         code.type = Script::TYPE_NONE;
 848         code.reg1 = 7;
 849         code.reg2 = 7;
 850         return code;
 851 }
 852
 853 void Interpreter::ReadScriptAddress(const ScriptToken &t, char *dest) {
 854         if (t.GetType() != ScriptToken::IDENTIFIER) {
 855                 throw Error("expected identifier for address");
 856         }
 857         if (source.IsDefined(t.Identifier())) {
 858                 const ParsedDefinition &def(GetDefinition(t.Identifier()));
 859                 void *addr(GetObject(def.type, t.Identifier()));
 860                 *reinterpret_cast<void **>(dest) = addr;
 861         } else {
 862                 throw Error("postponing values in scripts not implemented");
 863         }
 864 }
 865
 866 void Interpreter::ReadScriptInteger(const ScriptToken &t, char *dest) {
 867         if (t.GetType() == ScriptToken::IDENTIFIER) {
 868                 if (source.IsDefined(t.Identifier())) {
 869                         void *num(GetObject(TypeDescription::GetTypeId("Number"), t.Identifier()));
 870                         *reinterpret_cast<int *>(dest) = *reinterpret_cast<int *>(num);
 871                 } else {
 872                         throw Error("postponing values in scripts not implemented");
 873                 }
 874         } else if (t.GetType() == ScriptToken::LITERAL) {
 875                 *reinterpret_cast<int *>(dest) = t.GetLiteral()->GetNumber();
 876         } else {
 877                 throw Error("expected identifier or integer literal");
 878         }
 879 }
 880
 881 void Interpreter::ReadScriptVector(const ScriptToken &t, char *dest) {
 882         if (t.GetType() == ScriptToken::IDENTIFIER) {
 883                 if (source.IsDefined(t.Identifier())) {
 884                         void *vec(GetObject(TypeDescription::GetTypeId("Vector"), t.Identifier()));
 885                         *reinterpret_cast<Vector<int> *>(dest) = *reinterpret_cast<Vector<int> *>(vec);
 886                 } else {
 887                         throw Error("postponing values in scripts not implemented");
 888                 }
 889         } else if (t.GetType() == ScriptToken::LITERAL) {
 890                 *reinterpret_cast<Vector<int> *>(dest) = Vector<int>(t.GetLiteral()->GetX(), t.GetLiteral()->GetY());
 891         } else {
 892                 throw Error("expected identifier or vector literal");
 893         }
 894 }
 895
 896
 897 SDL_Surface *Interpreter::GetImage(const string &path) {
 898         std::map<string, SDL_Surface *>::const_iterator result(imageCache.find(path));
 899         if (result != imageCache.end()) {
 900                 return result->second;
 901         } else {
 902                 SDL_Surface *image(IMG_Load(path.c_str()));
 903                 imageCache.insert(make_pair(path, image));
 904                 return image;
 905         }
 906 }
 907
 908
 909 bool Interpreter::CanLink(const Value &v) const {
 910         return v.IsLiteral() || source.IsDefined(v.GetIdentifier());
 911 }
 912
 913 void Interpreter::Postpone(
 914                 char *object,
 915                 char *dest,
 916                 const std::string &identifier,
 917                 int type,
 918                 bool inlined,
 919                 bool aggregate) {
 920         postponedDefinitions.push_back(
 921                         PostponedDefinition(object, dest, identifier, type, inlined, aggregate));
 922 }
 923
 924
 925 void Interpreter::CreateTypeDescriptions() {
 926         {
 927                 TypeDescription &td(TypeDescription::Create(BOOLEAN_ID, "Boolean"));
 928                 td.SetDescription("Logical value which can be either true or false.");
 929                 td.SetSize(sizeof(bool));
 930         }
 931         {
 932                 TypeDescription &td(TypeDescription::Create(COLOR_ID, "Color"));
 933                 td.SetDescription(
 934                                 "A color in RGB format with an optional alpha channel.\n"
 935                                 "Components range from 0 to 255.\n"
 936                                 "Alpha defaults to 255 if omitted.");
 937                 td.SetSize(sizeof(Color));
 938         }
 939         {
 940                 TypeDescription &td(TypeDescription::Create(IMAGE_ID, "Image"));
 941                 td.SetDescription("Path to a PNG file with image data.");
 942                 td.SetSize(sizeof(SDL_Surface));
 943         }
 944         {
 945                 TypeDescription &td(TypeDescription::Create(NUMBER_ID, "Number"));
 946                 td.SetDescription("A signed integer.");
 947                 td.SetSize(sizeof(int));
 948         }
 949         {;
 950                 TypeDescription &td(TypeDescription::Create(PATH_ID, "Path"));
 951                 td.SetDescription("A path in the filesystem which is interpreted relative to the source file's location.");
 952                 td.SetSize(1);
 953                 td.AddSupertype(STRING_ID, 0);
 954         }
 955         {
 956                 TypeDescription &td(TypeDescription::Create(SCRIPT_ID, "Script"));
 957                 td.SetDescription("Collection of commands that define a behaviour.");
 958                 td.SetSize(sizeof(Script));
 959         }
 960         {
 961                 TypeDescription &td(TypeDescription::Create(STRING_ID, "String"));
 962                 td.SetDescription("Some characters.");
 963                 td.SetSize(1);
 964         }
 965         {
 966                 TypeDescription &td(TypeDescription::Create(VECTOR_ID, "Vector"));
 967                 td.SetDescription("A pair of numbers usually describing a 2D translation or offset.");
 968                 td.SetSize(sizeof(Vector<int>));
 969         }
 970 }
 971
 972 }