Free Hero Mesh

  * Returning a class from COLLIDE/COLLIDEBY to transform
  * Coordinate input (may be suitable for some kind of games)
  * Possibility to define auto-generation levels mode
* Editor
  * Mouse dragging
  * Level index editor
* Table of contents for levels (partially implemented)

  * Can be divisions by sections
* Deal better with allowing to skip past corrupted levels
* Picture editor/loading
  * Allowing more altimages
  * Batch insert multiple dependent image lumps
* Puzzle set catalog format (using with internet; a separate program)
* Inventory/replay hybrid view

 Bitwise:  band bor bxor bnot lsh rsh ,rsh

 Logical:  land lor lxor lnot

 Compare:  eq ne lt ,lt gt ,gt le ,le ge ,ge

 Misc:  Level _ in nin ret if else then c? m? n? . dup Trace

 Object:  Xloc Yloc Class Dir Misc1 Misc2 Misc3 Misc4 Misc5 Misc6 Misc7
   Temperature Density Player Input Bizarro CollisionLayers

Additionally, you can include numbers, strings (see below for their
meaning, which is different from the meaning in class codes), aggregate
names (with % at first), user flags (with ^ at first), class names, and
message names (both built-in messages and user messages are possible).
Accessing values of objects other than the current one is not possible.

The Trace instruction in the (LevelTable) block is not the same as in the
class codes. In this block, it doesn't consume anything from the stack;
instead, if both -t and -v switches are enabled, then it will display data
relating to the level table calculation on stdout, at the time when the
level table is loaded. (If the table is dropped, it will automatically be
reloaded the next time it is accessed.)

If a string is found where an instruction is expected in this block, then
unlike class codes it is not simply pushing the string to the stack.
Instead, if it starts with @ then the rest of it is a literal string, but
otherwise it represents a pattern to match. If the match is successful,
it pushes the matched substring (or sometimes, a number) to the stack,
and then pushes 1; if unsuccessful, only pushes 0. These patterns will
match the title string of the level. Pattern codes are:

  =    Follow by a delimited string; match that string at the current
        position and skip past it, or if it doesn't match, fail.
  /    Follow by a delimited string; match that string at the current or
        any later position (at the first place where it is found), or if
        it doesn't match, fail.
  [    Set beginning of slice.
  ]    Set end of slice.
  (    Set beginning of slice (same as the [ command);
  )    Set end of slice, but use the position just before the matched item
        instead of just after it.
  \n   Skip until a line break of horizontal bar, and past it. If it is
        followed by any more consecutive line breaks without anything else
        in between, skips those ones too.
  \d   Follow by some text and then : and \ or just \ to skip to and find
        the data in the string that has the same text. If it contains a
        question mark then any single character is matched. Between : and \
        you can have usual other matching commands such as [ and ].
  +    Follow by one more character, skip past any number of them.
  -    Skip past any number of digits.
  _    Skip past any number of spaces and line breaks.
  <    Rewind back to the beginning.
  >    Skip to the end.
  #    Successful match; the result is a number within the slice, converted
        from a string (parsed as decimal) to a number.
  $    Successful match; the result is the matched slice.
  %    Successful match; the result is the length of the matched slice.

A "delimited string" in this block is delimited by any printable
character on both sides (except a character with code less than 32).

(The above list of pattern codes maybe it isn't explained very well;
hopefully someone else know how to improve it better.)

typedef struct {
  Value misc1,misc2,misc3;
  Uint8 x,y,dir,bizarro;
  Uint16 class;
} ObjInfo;

static const unsigned char*ll_find(const unsigned char*p,Uint8 c) {
  int j;
  for(j=0;*p;p++) {
    if(j) {
      if(*p=='\\') j=0;
    } else {
      if(*p==c) return p;
      if(*p==14 || *p==30) j=1;
      if(*p==31 && p[1]) p++;
    }
  }
  return 0;
}

static inline Sint16 ll_string(const unsigned char*str,const unsigned char*title,Value*stack,Sint16 sp) {
  const unsigned char*ps=str; // pointer of string
  const unsigned char*pt=title; // pointer of title
  const unsigned char*so=0; // start offset
  const unsigned char*eo=0; // end offset
  const unsigned char*pp=pt;
  const unsigned char*q;
  int i,j,k;
  while(*ps) {
    switch(*ps++) {
      case '=':
        k=*ps++;
        if(k<32) return 64;
        while(*ps && *ps!=k && *pt==*ps) ps++,pt++;
        if(*ps!=k) goto notfound;
        ps++;
        break;
      case '/':
        k=*ps++;
        if(k<32) return 64;
        if(*ps==k) goto bad;
        q=strchr(ps,k);
        if(!q) goto bad;
        j=q-ps;
        while(*pt) {
          pt=ll_find(pt,*ps);
          if(!pt) goto notfound;
          for(i=1;i<j && pt[i]==ps[i];i++);
          if(i==j) break;
          pt++;
        }
        if(!*pt) goto notfound;
        pp=pt;
        ps+=j+1;
        pt+=j;
        break;
      case '[': so=pt; break;
      case ']': eo=pt; break;
      case '(': so=pt; break;
      case ')': eo=pp; break;
      case 10: // "\n"
        if(pt==title) break;
        for(j=0;*pt;pt++) {
          if(j) {
            if(*pt=='\\') j=0;
          } else {
            if(*pt==10 || *pt==15) break;
            if(*pt==14 || *pt==30) j=1;
            if(*pt==31 && pt[1]) pt++;
          }
        }
        if(!*pt) goto notfound;
        pp=pt++;
        while(*pt==10) pt++;
        break;
      case 30: // "\d"
        re:
        pp=pt=ll_find(pt,30);
        if(!pt) goto notfound;
        for(i=0;ps[i];i++) {
          if(ps[i]==':' || ps[i]=='\\') break;
          if(ps[i]!=pt[i] && ps[i]!='?') {
            pt+=i;
            goto re;
          }
        }
        ps+=i+1;
        pt+=i+2;
        break;
      case '+':
        k=*ps++;
        if(k<31) return 64;
        if(k==31) {
          k=*ps++;
          if(!k) return 64;
          while(*pt==31 && pt[1]==k) pt+=2;
        } else {
          while(*pt==k) pt++;
        }
        break;
      case '-':
        while(*pt>='0' && *pt<='9') pt++;
        break;
      case '_':
        while(*pt==' ' || *pt==10) pt++;
        break;
      case '\\':
        pt=ll_find(pt,'\\');
        if(!pt) goto notfound;
        pp=pt++;
        break;
      case '.':
        if(*pt==31 && pt[1]) pt+=2;
        else if(*pt==14 || *pt==30) pt=strchr(pt,'\\'),pt+=pt?1:0;
        else if(*pt) pt++;
        if(!pt) return 64;
        break;
      case '<': pt=title; break;
      case '>': pt+=strlen(pt); break;
      case '#':
        if(!so || !eo || so>eo) break;
        k=0;
        while(*so>='0' && *so<='9') k=10*k+*so++-'0';
        stack[sp++]=NVALUE(k);
        stack[sp++]=NVALUE(1);
        return sp;
      case '$':
        if(!so || !eo || so>eo) break;
        stack[sp++]=UVALUE(((so-title)<<16)|(eo-title),TY_FOR);
        stack[sp++]=NVALUE(1);
        return sp;
      case '%':
        if(!so || !eo || so>eo) break;
        stack[sp++]=NVALUE(eo-so);
        stack[sp++]=NVALUE(1);
        return sp;
      default: bad:
        if(main_options['v']) fprintf(stderr,"Invalid character (0x%02X) in string in LevelTable definition\n",ps[-1]);
        return 64;
    }
  }
  notfound: stack[sp++]=NVALUE(0); return sp;
}

static inline Uint32 ll_in(Value*stack,Sint16 top,Sint16 m) {
  while(--top>m) if(stack[top].t==stack[m-1].t && stack[top].u==stack[m-1].u) return 1;
  return 0;
}

#define ArithOp1(aa) ({ if(sp<1 || stack[sp-1].t) goto bad; Value t1=stack[sp-1]; stack[sp-1]=NVALUE(aa); })
#define ArithOp2(aa) ({ if(sp<2 || stack[sp-1].t || stack[sp-2].t) goto bad; Value t1=stack[sp-2]; Value t2=stack[sp-1]; sp--; stack[sp-1]=NVALUE(aa); })
#define ArithDivOp2(aa) ({ if(sp<2 || stack[sp-1].t || stack[sp-2].t || !stack[sp-1].u) goto bad; Value t1=stack[sp-2]; Value t2=stack[sp-1]; sp--; stack[sp-1]=NVALUE(aa); })
#define OtherOp1(aa) ({ if(sp<1) goto bad; Value t1=stack[sp-1]; stack[sp-1]=(aa); })
#define OtherOp2(aa) ({ if(sp<2) goto bad; Value t1=stack[sp-2]; Value t2=stack[sp-1]; sp--; stack[sp-1]=(aa); })

static Sint16 level_table_exec(Uint16 ptr,const unsigned char*lvl,long sz,ObjInfo*ob,Value*stack,Value*agg) {
  Sint16 sp=0;
  Uint32 k,m;
  while(sp<62) switch(ll_code[ptr++]) {
    case 0 ... 255: stack[sp++]=NVALUE(ll_code[ptr-1]); break;
    case 0x0200 ... 0x02FF: stack[sp++]=MVALUE(ll_code[ptr-1]&255); break;
    case 0x4000 ... 0x7FFF: stack[sp++]=CVALUE(ll_code[ptr-1]&0x3FFF); break;

    case OP_CLASS: if(!ob) goto bad; stack[sp++]=CVALUE(ob->class); break;
    case OP_COLLISIONLAYERS: if(!ob) goto bad; stack[sp++]=NVALUE(classes[ob->class]->collisionLayers); break;
    case OP_DELTA: ArithOp2(t1.u>t2.u?t1.u-t2.u:t2.u-t1.u); break;
    case OP_DENSITY: if(!ob) goto bad; stack[sp++]=NVALUE(classes[ob->class]->density); break;
    case OP_DIR: if(!ob) goto bad; stack[sp++]=NVALUE(ob->dir); break;
    case OP_DIV: ArithDivOp2(t1.u/t2.u); break;
    case OP_DIV_C: ArithDivOp2(t1.s/t2.s); break;
    case OP_DROP: if(sp) --sp; break;
    case OP_DUP: if(!sp) goto bad; stack[sp]=stack[sp-1]; sp++; break;
    case OP_EQ: OtherOp2(NVALUE((t1.u==t2.u && t1.t==t2.t)?1:0)); break;
    case OP_GE: ArithOp2(t1.u>=t2.u?1:0); break;
    case OP_GE_C: ArithOp2(t1.s>=t2.s?1:0); break;
    case OP_GOTO: ptr=ll_code[ptr]; break;
    case OP_GT: ArithOp2(t1.u>t2.u?1:0); break;
    case OP_GT_C: ArithOp2(t1.s>t2.s?1:0); break;
    case OP_IF:

    case OP_MOD: ArithDivOp2(t1.u%t2.u); break;
    case OP_MOD_C: ArithDivOp2(t1.s%t2.s); break;
    case OP_MUL: ArithOp2(t1.u*t2.u); break;
    case OP_MUL_C: ArithOp2(t1.s*t2.s); break;
    case OP_NE: OtherOp2(NVALUE((t1.u==t2.u && t1.t==t2.t)?0:1)); break;
    case OP_NEG: ArithOp1(-t1.s); break;
    case OP_PLAYER: if(!ob) goto bad; stack[sp++]=NVALUE(classes[ob->class]->cflags&CF_PLAYER?1:0); break;
    case OP_QC: OtherOp1(NVALUE(t1.t==TY_CLASS?1:0)); break;
    case OP_QM: OtherOp1(NVALUE(t1.t==TY_MESSAGE?1:0)); break;
    case OP_QN: OtherOp1(NVALUE(t1.t==TY_NUMBER?1:0)); break;
    case OP_RET: return sp;
    case OP_RSH: ArithOp2(t2.u&~31?0:t1.u>>t2.u); break;
    case OP_RSH_C: ArithOp2(t2.u&~31?(t1.s<0?-1:0):t1.s>>t2.u); break;
    case OP_STRING:
      k=ll_code[ptr++];
      if(stringpool[k][0]=='@') stack[sp++]=UVALUE(k,TY_STRING); else sp=ll_string(stringpool[k],lvl+6,stack,sp);
      break;
    case OP_SUB: ArithOp2(t1.u-t2.u); break;
    case OP_TEMPERATURE: if(!ob) goto bad; stack[sp++]=NVALUE(classes[ob->class]->temperature); break;
    case OP_TRACE:
      if(main_options['t'] && main_options['v']) {
        printf("'' ptr=0x%04X sp=%d ll_ndata=%d ll_naggregate=%d\n",ptr,sp,ll_ndata,ll_naggregate);
        for(k=0;k<sp;k++) printf("''  k=%d u=%u t=%u\n",k,stack[k].u,stack[k].t);
      }
      break;
    case OP_USERFLAG:
      if(!ob) goto bad;
      if(ll_code[ptr]<0x1020) k=classes[ob->class]->misc4;
      else if(ll_code[ptr]<0x1040) k=classes[ob->class]->misc5;
      else if(ll_code[ptr]<0x1060) k=classes[ob->class]->misc6;
      else if(ll_code[ptr]<0x1080) k=classes[ob->class]->misc7;
      else k=classes[ob->class]->collisionLayers;
      stack[sp].t=TY_NUMBER;
      stack[sp].u=(k&(1LL<<(ll_code[ptr++]&31)))?1:0;
      sp++;
      break;
    case OP_XLOC: if(!ob) goto bad; stack[sp++]=NVALUE(ob->x); break;
    case OP_YLOC: if(!ob) goto bad; stack[sp++]=NVALUE(ob->y); break;
    default: goto bad;
  }
  bad:
  if(main_options['v']) fprintf(stderr,"Error in LevelTable definition (at 0x%04X)\n",ptr);
  return -1;
}

static void ll_append_str(sqlite3_str*str,const unsigned char*p,long n) {
  const unsigned char*end=p+n;
  while(p<end) {
    if(*p>=32) {
      sqlite3_str_appendchar(str,1,*p++);
    } else if(*p==31) {
      p++;
      if(p<end && *p) sqlite3_str_appendchar(str,1,*p++);
    } else if(*p==10 || *p==15) {
      sqlite3_str_appendchar(str,1,32);
      p++;
    } else if(*p==14 || *p==30) {
      p=memchr(p,'\\',end-p);
      if(!p) return;
      p++;
    } else {
      p++;
    }
  }
}

static void calculate_level_columns(sqlite3_stmt*st,const unsigned char*lvl,long sz) {
  ObjInfo ob;
  ObjInfo mru[2];
  Value stack[64];
  Value agg[64];
  int i,j,n,z;

    }
  }
  // Data column values
  for(i=0;i<ll_ndata;i++) {
    j=level_table_exec(ll_data[i].ptr,lvl,sz,0,stack,agg);
    if(j<=0 || stack->t==TY_MARK) {
      sqlite3_bind_null(st,i+8);
    } else if(stack->t==TY_STRING || stack->t==TY_FOR || stack->t==TY_LEVELSTRING) {
      sqlite3_str*str=sqlite3_str_new(userdb);
      for(n=0;n<j;n++) switch(stack[n].t) {
        case TY_NUMBER:
          sqlite3_str_appendf(str,"%u",(unsigned int)stack[n].u);
          break;
        case TY_CLASS:
          z=stack[n].u&0x3FFF;
          if(classes[z] && classes[z]->name) sqlite3_str_appendf(str,"%s",classes[z]->name);
          break;
        case TY_LEVELSTRING:
          if(stack[n].u>=nlevelstrings) break;
          ll_append_str(str,levelstrings[stack[n].u],strlen(levelstrings[stack[n].u]));
          break;
        case TY_STRING:
          sqlite3_str_appendall(str,stringpool[stack[n].u]+1);
          break;
        case TY_FOR:
          ll_append_str(str,lvl+(stack[n].u>>16)+6,stack[n].u&0xFFFF);
          break;
        // Otherwise, do nothing
      }
      if(z=sqlite3_str_length(str)) {
        sqlite3_bind_blob(st,i+8,sqlite3_str_finish(str),z,sqlite3_free);
      } else {
        sqlite3_free(sqlite3_str_finish(str));
        sqlite3_bind_zeroblob(st,i+8,0);
      }
    } else {
      if(ll_data[i].sgn) sqlite3_bind_int64(st,i+8,stack->s); else sqlite3_bind_int64(st,i+8,stack->u);
    }
  }
}

static int vt1_levels_open(sqlite3_vtab*vt,sqlite3_vtab_cursor**cur) {
  sqlite3_str*str;
  sqlite3_stmt*st1;

  int i;
  const char*p;
  sqlite3_int64 v;
  if(t==SQLITE_NULL) return;
  if(dc->flag&1) w=255;
  if(t==SQLITE_BLOB || t==SQLITE_TEXT) {
    blob:
    i=snprintf(buf,w,"%s",sqlite3_column_text(st,nc));
    if(dc->form[0]=='R' && i<w) a=w-i;
    if(dc->flag&2) co=0xFF;
  } else {
    // This implementation does not check that the format is necessarily valid.
    // You should not rely on the use of any undocumented format.
    v=sqlite3_column_int64(st,nc);
    if(dc->flag&2) {
      co=0xFF;