Free Hero Mesh

'- ' <count>
  Rewind that many moves.

'= ' <count>
  Restart and replay that many moves.

'^T'
  Display the level title popup.

'^o' <location>
  List objects at the specified coordinates.


=== Editor commands ===

'^c'

Uint32 firstobj=VOIDLINK;
Uint32 lastobj=VOIDLINK;
Uint32 playfield[64*64]; // bottom-most object per cell
Uint8 pfwidth,pfheight;
Sint8 gameover,key_ignored;
Uint8 generation_number_inc;
Uint32 move_number;
unsigned char*quiz_text;

typedef struct {
  Uint16 msg;
  Uint32 from;
  Value arg1,arg2,arg3;
} MessageVars;

  return send_message(from,v_object(to),msg.u,arg1,arg2,arg3);
}

static inline Value v_send_self(Uint32 from,Value msg,Value arg1,Value arg2,Value arg3) {
  if(msg.t!=TY_MESSAGE) Throw("Type mismatch");
  return send_message(from,from,msg.u,arg1,arg2,arg3);
}

static void v_set_popup(Uint32 from,int argc) {
  const unsigned char*t;
  const unsigned char*u;
  sqlite3_str*s;
  Value v;
  int argi=1;
  if(argc>32 || argc<0) Throw("Too many arguments");
  vstackptr-=argc;
  v=Pop();
  if(quiz_text) return;
  if(argc) {
    argc++;
    if(v.t!=TY_STRING && v.t!=TY_LEVELSTRING) Throw("Type mismatch");
    s=sqlite3_str_new(userdb);
    t=value_string_ptr(v);
    while(*t) {
      if(u=strchr(t,'%')) {
        sqlite3_str_append(s,t,u-t);
        t=u+2;
        switch(u[1]) {
          case 0:
            t=u+1;
            break;
          case 'c':
            if(argi==argc) break;
            v=vstack[vstackptr+argi++];
            if(v.t==TY_NUMBER) {
              sqlite3_str_appendchar(s,1,31);
              sqlite3_str_appendchar(s,1,v.u&255?:255);
            }
            break;
          case 'd':
            if(argi==argc) break;
            v=vstack[vstackptr+argi++];
            if(v.t==TY_NUMBER) sqlite3_str_appendf(s,"%d",(signed int)v.s);
            break;
          case 'i':
            if(argi>=argc-1) break;
            if(vstack[vstackptr+argi].t==TY_CLASS && vstack[vstackptr+argi+1].t==TY_NUMBER) {
              Class*c=classes[vstack[vstackptr+argi].u];
              int n=vstack[vstackptr+argi+1].u&255;
              if(n<c->nimages) sqlite3_str_appendf(s,"\x0E\x07:%d\\",c->images[n]&0x7FFF);
            }
            argi+=2;
            break;
          case 's':
            if(argi==argc) break;
            v=vstack[vstackptr+argi++];
            switch(v.t) {
              case TY_STRING: case TY_LEVELSTRING:
                sqlite3_str_appendf(s,"%s",value_string_ptr(v));
                break;
              case TY_NUMBER:
                sqlite3_str_appendf(s,"%llu",(sqlite3_int64)v.u);
                break;
              case TY_CLASS:
                sqlite3_str_appendf(s,"%s",classes[v.u]->name);
                break;
              default:
                Throw("Type mismatch");
            }
            break;
          case 'u':
            if(argi==argc) break;
            v=vstack[vstackptr+argi++];
            if(v.t==TY_NUMBER) sqlite3_str_appendf(s,"%u",(unsigned int)v.u);
            break;
          case 'x':
            if(argi==argc) break;
            v=vstack[vstackptr+argi++];
            if(v.t==TY_NUMBER) sqlite3_str_appendf(s,"%x",(unsigned int)v.u);
            break;
          case 'X':
            if(argi==argc) break;
            v=vstack[vstackptr+argi++];
            if(v.t==TY_NUMBER) sqlite3_str_appendf(s,"%X",(unsigned int)v.u);
            break;
          case '%':
            sqlite3_str_appendchar(s,1,'%');
            break;
        }
      } else {
        sqlite3_str_appendall(s,t);
        break;
      }
    }
    sqlite3_str_appendchar(s,1,0);
    quiz_text=sqlite3_str_finish(s);
  } else {
    switch(v.t) {
      case TY_STRING: case TY_LEVELSTRING:
        quiz_text=sqlite3_mprintf("%s",value_string_ptr(v));
        break;
      case TY_NUMBER:
        quiz_text=sqlite3_mprintf("%llu",(sqlite3_int64)v.u);
        break;
      case TY_CLASS:
        quiz_text=sqlite3_mprintf("%s",classes[v.u]->name);
        break;
      default:
        Throw("Type mismatch");
    }
  }
  if(!quiz_text) fatal("Allocation failed\n");
  t=quiz_text;
  while(*t) {
    if(*t==16) {
      quiz_obj.t=objects[from]->generation?:1;
      quiz_obj.u=from;
    }
    if(*t==31 && t[1]) t+=2; else t+=1;
  }
}

// Here is where the execution of a Free Hero Mesh bytecode subroutine is executed.
#define NoIgnore() do{ changed=1; }while(0)
#define GetVariableOf(a,b) (i=v_object(Pop()),i==VOIDLINK?NVALUE(0):b(objects[i]->a))
#define GetVariableOrAttributeOf(a,b) (t2=Pop(),t2.t==TY_CLASS?NVALUE(classes[t2.u]->a):(i=v_object(t2),i==VOIDLINK?NVALUE(0):b(objects[i]->a)))
#define Numeric(a) do{ if((a).t!=TY_NUMBER) Throw("Type mismatch"); }while(0)
#define DivideBy(a) do{ Numeric(a); if(!(a).u) Throw("Division by zero"); }while(0)

    case OP_OBJCLASSAT: StackReq(3,1); t3=Pop(); t2=Pop(); t1=Pop(); Push(v_obj_class_at(t1,t2,t3)); break;
    case OP_OBJDIR: StackReq(1,1); t2=Pop(); Numeric(t2); i=obj_dir(obj,t2.u); Push(OVALUE(i)); break;
    case OP_OBJDIR_C: StackReq(2,1); t2=Pop(); Numeric(t2); i=obj_dir(v_object(Pop()),t2.u); Push(OVALUE(i)); break;
    case OP_OBJLAYERAT: StackReq(3,1); t3=Pop(); Numeric(t3); t2=Pop(); Numeric(t2); t1=Pop(); Numeric(t1); i=obj_layer_at(t1.u,t2.u,t3.u); Push(OVALUE(i)); break;
    case OP_OBJTOPAT: StackReq(2,1); t2=Pop(); Numeric(t2); t1=Pop(); Numeric(t1); i=obj_top_at(t1.u,t2.u); Push(OVALUE(i)); break;
    case OP_PLAYER: StackReq(0,1); if(classes[o->class]->cflags&CF_PLAYER) Push(NVALUE(1)); else Push(NVALUE(0)); break;
    case OP_PLAYER_C: StackReq(1,1); GetClassFlagOf(CF_PLAYER); break;
    case OP_POPUP: StackReq(1,0); v_set_popup(obj,0); break;
    case OP_POPUPARGS: i=code[ptr++]; StackReq(i+1,0); v_set_popup(obj,i); break;
    case OP_RET: return;
    case OP_ROT: StackReq(3,3); t3=Pop(); t2=Pop(); t1=Pop(); Push(t2); Push(t3); Push(t1); break;
    case OP_ROTBACK: StackReq(3,3); t3=Pop(); t2=Pop(); t1=Pop(); Push(t3); Push(t1); Push(t2); break;
    case OP_RSH: StackReq(2,1); t2=Pop(); Numeric(t2); t1=Pop(); Numeric(t1); Push(NVALUE(t2.u&~31?0:t1.u>>t2.u)); break;
    case OP_RSH_C: StackReq(2,1); t2=Pop(); Numeric(t2); t1=Pop(); Numeric(t1); Push(NVALUE(t2.u&~31?(t1.s<0?-1:0):t1.s>>t2.u)); break;
    case OP_SELF: StackReq(0,1); Push(OVALUE(obj)); break;
    case OP_SEND: StackReq(3,1); t4=Pop(); t3=Pop(); t2=Pop(); Push(v_send_self(obj,t2,t3,t4,NVALUE(0))); break;

    case OP_STEALTHY_EC: NoIgnore(); StackReq(2,0); SetFlagOf(OF_STEALTHY); break;
    case OP_STRENGTH: StackReq(0,1); Push(NVALUE(o->strength)); break;
    case OP_STRENGTH_C: StackReq(1,1); Push(GetVariableOrAttributeOf(strength,NVALUE)); break;
    case OP_STRENGTH_E: NoIgnore(); StackReq(1,0); t1=Pop(); Numeric(t1); o->strength=t1.u; break;
    case OP_STRENGTH_E16: NoIgnore(); StackReq(1,0); t1=Pop(); Numeric(t1); o->strength=t1.u&0xFFFF; break;
    case OP_STRENGTH_EC: NoIgnore(); StackReq(2,0); t1=Pop(); Numeric(t1); i=v_object(Pop()); if(i!=VOIDLINK) o->strength=t1.u; break;
    case OP_STRENGTH_EC16: NoIgnore(); StackReq(2,0); t1=Pop(); Numeric(t1); i=v_object(Pop()); if(i!=VOIDLINK) o->strength=t1.u; break;
    case OP_STRING: StackReq(0,1); Push(UVALUE(code[ptr++],TY_STRING)); break;
    case OP_SOUND: StackReq(2,0); t2=Pop(); t1=Pop(); break; // Sound not implemented at this time
    case OP_SUB: StackReq(2,1); t2=Pop(); Numeric(t2); t1=Pop(); Numeric(t1); Push(NVALUE(t1.u-t2.u)); break;
    case OP_SWAP: StackReq(2,2); t1=Pop(); t2=Pop(); Push(t1); Push(t2); break;
    case OP_SYNCHRONIZE: StackReq(2,0); t2=Pop(); Numeric(t2); t1=Pop(); Numeric(t1); animate_sync(obj,t1.u,t2.u); break;
    case OP_TEMPERATURE: StackReq(0,1); Push(NVALUE(o->temperature)); break;
    case OP_TEMPERATURE_C: StackReq(1,1); Push(GetVariableOrAttributeOf(temperature,NVALUE)); break;
    case OP_TEMPERATURE_E: NoIgnore(); StackReq(1,0); t1=Pop(); Numeric(t1); o->temperature=t1.u; break;

  return t;
}

void annihilate(void) {
  Uint32 i;
  for(i=0;i<64*64;i++) playfield[i]=VOIDLINK;
  firstobj=lastobj=VOIDLINK;
  if(quiz_text) {
    sqlite3_free(quiz_text);
    quiz_text=0;
  }
  if(!objects) return;
  for(i=0;i<nobjects;i++) if(objects[i]) {
    animfree(objects[i]->anim);
    free(objects[i]);
  }
  nobjects=0;
  free(objects);

  if(key_ignored) {
    quiz_obj=NVALUE(0);
    return changed?"Invalid use of IgnoreKey":0;
  }
  move_number++;
  // Beginning phase
  if(!all_flushed) broadcast(m,0,MSG_BEGIN_TURN,m==VOIDLINK?NVALUE(objects[m]->x):NVALUE(0),m==VOIDLINK?NVALUE(objects[m]->y):NVALUE(0),v,0);
  // Trigger phase
  
  // Ending phase
  
  // Animation phase
  
  // Cleanup phase
  for(n=0;n<nobjects;n++) if(objects[n] && (objects[n]->oflags&OF_DESTROYED)) objtrash(n);
  if(generation_number<=TY_MAXTYPE) return "Too many generations of objects";
  return 0;
}

  draw_text(24,32,"x",0xF0,0xF5);
  x=x>=left_margin?(x-left_margin)/picture_size+1:0;
  y=y/picture_size+1;
  if(x>0 && y>0 && x<=pfwidth && y<=pfheight) snprintf(buf,8,"(%2d,%2d)",x,y);
  else strcpy(buf,"       ");
  draw_text(0,40,buf,0xF0,0xF1);
  SDL_UnlockSurface(screen);
  if(quiz_text) draw_popup(quiz_text);
  SDL_Flip(screen);
  set_cursor(XC_arrow);
}

static void continue_animation(void) {
  Uint32 n=firstobj;
  Object*o;

      draw_text(200,y,"$",0xF0,0xFB);
      draw_text(208,y,classes[v.u]->name,0xF0,0xFB);
      break;
    case TY_MESSAGE:
      snprintf(buf,255,"%s%s",v.u<256?"":"#",v.u<256?standard_message_names[v.u]:messages[v.u-256]);
      draw_text(200,y,buf,0xF0,0xFD);
      break;
    case TY_LEVELSTRING:
      
    case TY_LEVELSTRING: case TY_STRING:
      draw_text(200,y,"<String>",0xF0,0xF9);
      break;
    case TY_STRING:
      
      break;
    case TY_SOUND: case TY_USOUND:
      draw_text(200,y,"<Sound>",0xF0,0xF6);
      break;
    default:
      snprintf(buf,80,"<%lu:%lu>",(long)v.u,(long)v.t);
      draw_text(200,y,buf,0xF0,0xFA);

  r.w=screen->w;
  r.h=screen->h;
  SDL_FillRect(screen,&r,0xF0);
  SDL_LockSurface(screen);
  exam_value("Self:",0,OVALUE(n));
  exam_value("Class:",1,CVALUE(o->class));
  exam_value("Image:",2,NVALUE(o->image));
  if(classes[o->class]->cflags&CF_QUIZ) goto quiz;
  exam_value("Dir:",3,NVALUE(o->dir));
  exam_value("Misc1:",4,o->misc1);
  exam_value("Misc2:",5,o->misc2);
  exam_value("Misc3:",6,o->misc3);
  exam_value("Misc4:",7,o->misc4);
  exam_value("Misc5:",8,o->misc5);
  exam_value("Misc6:",9,o->misc6);

  exam_value("Inertia:",24,NVALUE(o->inertia));
  exam_hardsharp("Hardness:",25,o->hard);
  exam_hardsharp("Sharpness:",26,o->sharp);
  while(sqlite3_step(st)==SQLITE_ROW) {
    i=sqlite3_column_int(st,1);
    exam_value(sqlite3_column_text(st,0),i+28,o->uservars[i]);
  }
  quiz:
  sqlite3_reset(st);
  SDL_UnlockSurface(screen);
  SDL_Flip(screen);
  while(SDL_WaitEvent(&ev)) switch(ev.type) {
    case SDL_KEYDOWN:
      switch(ev.key.keysym.sym) {
        case SDLK_ESCAPE: case SDLK_RETURN: case SDLK_KP_ENTER: sqlite3_finalize(st); return;

  snprintf(buf,255," %d objects at (%d,%d): ",count,(xy&63)+1,(xy/64)+1);
  SDL_LockSurface(screen);
  draw_text(0,0,buf,0xF7,0xF0);
  n=t;
  for(i=0;i<scroll && n!=VOIDLINK;i++) n=objects[n]->down;
  for(i=0;i<screen->h/8 && n!=VOIDLINK;i++) {
    o=objects[n];
    snprintf(buf,255," %8d: %-14.14s %3d %s",n,classes[o->class]->name,o->image,dirs[o->dir&7]);
    draw_text(24,r.y,buf,0xF1,o->generation?0xFF:0xF8);
    snprintf(buf,255," %8d: %-14.14s %3d %s",n,classes[o->class]->name,o->image,classes[o->class]->cflags&CF_QUIZ?"":dirs[o->dir&7]);
    draw_text(24,r.y,buf,0xF1,o->generation?(classes[o->class]->cflags&CF_PLAYER?0xFE:0xFF):0xF8);
    n=o->down;
    r.y+=8;
  }
  SDL_UnlockSurface(screen);
  SDL_Flip(screen);
  while(SDL_WaitEvent(&ev)) {
    if(ev.type!=SDL_VIDEOEXPOSE) {

      }
      inputs[inputs_count++]=number;
      return 0;
    case '^E': // Edit
      return -2;
    case '^Q': // Quit
      return -1;
    case '^T': // Show title
      modal_draw_popup(level_title);
      return prev;
    case '^o': // List objects
      list_objects_at(number-65);
      return prev;
    case 'go': // Select level
      begin_level(number);
      return 1;
    default:

      case SDL_QUIT:
        exit(0);
        break;
      case SDL_MOUSEMOTION:
        show_mouse_xy(&ev);
        break;
      case SDL_USEREVENT:
        if(!gameover) continue_animation();
        if(!gameover && !quiz_text) continue_animation();
        timerflag=0;
        break;
      case SDL_MOUSEBUTTONDOWN:
        if(ev.button.x<left_margin) {
          
          break;
        } else {

void draw_cell(int x,int y);
const char*screen_prompt(const char*txt);
int screen_message(const char*txt);
void load_pictures(void);

int scrollbar(int*cur,int page,int max,SDL_Event*ev,SDL_Rect*re);

void draw_popup(const unsigned char*txt);
int modal_draw_popup(const unsigned char*txt);

// == class ==

#define CF_PLAYER 0x01
#define CF_INPUT 0x02
#define CF_COMPATIBLE 0x04
#define CF_QUIZ 0x08
#define CF_GROUP 0x10 // this is a group of classes; you can't create an object of this class

extern Value globals[0x800];
extern Uint32 firstobj,lastobj;
extern Uint32 playfield[64*64];
extern Uint8 pfwidth,pfheight;
extern Sint8 gameover,key_ignored;
extern Uint8 generation_number_inc;
extern Uint32 move_number;
extern unsigned char*quiz_text;

const char*value_string_ptr(Value v);
void pfunlink(Uint32 n);
void pflink(Uint32 n);
Uint32 objalloc(Uint16 c);
void objtrash(Uint32 n);
void annihilate(void);

  f=(y1-y0)/(double)(max+page);
  *cur=(y-y0+0.5)/f;
  draw_scrollbar(cur,page,max,x0,y0,x1,y1);
  SDL_Flip(screen);
  set_cursor(XC_sb_right_arrow);
  return 1;
}

// Popup text

/*
  \0 to \7 (1 to 8) - Colours
  \b (15) - Horizontal line
  \c (12) - Centre align
  \i (14) - Image of class
  \l (11) - Left align
  \n (10) - Line break
  \q (16) - Quiz button
  \x (31) - Hex escape
*/

typedef struct {
  Uint8 a,h;
  Uint16 w;
} PopLine;

static void pop_bar(int x,int y,PopLine*li,int w) {
  
}

static void pop_char(int x,int y,PopLine*li,Uint8 c,Uint8 v) {
  Uint8*p=screen->pixels;
  Uint16 pitch=screen->pitch;
  int xx,yy;
  const unsigned char*f=fontdata+(v<<3);
  if(li->h>8) y+=(li->h-8)/2;
  if(y+8>=screen->h || x+8>=screen->w) return;
  p+=y*pitch+x;
  for(yy=0;yy<8;yy++) {
    for(xx=0;xx<8;xx++) p[xx]=(*f<<xx)&128?c:0xF7;
    p+=pitch;
    ++f;
  }
}

static void pop_image(int x,int y,PopLine*li,const unsigned char*t) {
  const unsigned char*p=strchr(t,':');
  int i,n;
  if(!p) return;
  n=strtol(p+1,0,10);
  if(li->h>picture_size) y+=(li->h-picture_size)/2;
  if(y+picture_size>=screen->h || x+picture_size>=screen->w) return;
  SDL_UnlockSurface(screen);
  if(p==t+1 && *t==7) {
    // This case is used for %i substitutions
    draw_picture(x,y,n);
  } else if(p) {
    for(i=1;i<0x4000;i++) if(classes[i]) {
      if(strlen(classes[i]->name)==p-t && !memcmp(t,classes[i]->name,p-t)) {
        if(n>=0 && n<classes[i]->nimages) draw_picture(x,y,classes[i]->images[n]&0x7FFF);
        break;
      }
    }
  }
  SDL_LockSurface(screen);
}

static void pop_quiz(int x,int y,PopLine*li,Uint8 c,Uint8 v) {
  
}

void draw_popup(const unsigned char*txt) {
  static colo[8]={1,144,188,173,83,98,218,15};
  static PopLine li[64];
  SDL_Rect r;
  int bx,by,x,y,c;
  int ln=0; // line number
  int lh=8; // height of current line
  int th=0; // total height
  int lw=0; // width of current line
  int tw=0; // total width
  const unsigned char*p=txt;
  li[0].w=li[0].h=li[0].a=0;
  // Figure out size
  while(ln<64 && *p) switch(*p++) {
    case 1 ... 8:
      // needing doing nothing yet
      break;
    case 10:
      th+=lh;
      li[ln].h=lh;
      li[ln].w=lw;
      if(tw<lw) tw=lw;
      if(*p && *p!=15) lh=8; else lh=0;
      lw=0;
      ln++;
      if(ln<64) li[ln].a=li[ln-1].a;
      break;
    case 11: case 12:
      li[ln].a=p[-1]-11;
      break;
    case 14:
      if(lh<picture_size) lh=picture_size;
      lw+=picture_size;
      p=strchr(p,'\\')?:"";
      if(*p) p++;
      break;
    case 15:
      th+=lh+8;
      li[ln].h=lh;
      li[ln].w=lw;
      if(tw<lw) tw=lw;
      lh=8;
      lw=0;
      ln++;
      if(ln<64) li[ln].a=li[ln-1].a;
      break;
    case 16:
      lw+=24;
      if(lh<16) lh=16;
      if(*p) p++;
      break;
    case 31:
      lw+=8;
      if(*p) p++;
      break;
    default:
      lw+=8;
  }
  done:
  if(ln<64) li[ln].h=lh,li[ln].w=lw;
  p=txt;
  th+=lh;
  if(tw<lw) tw=lw;
  if(tw>screen->w-32) tw=screen->w-32;
  if(th>screen->h-32) th=screen->h-32;
  bx=(screen->w-tw-8)/2;
  by=(screen->h-th-8)/2;
  // Draw box
  r.x=bx; r.y=by; r.w=tw+16; r.h=th+16;
  SDL_FillRect(screen,&r,0xF7);
  r.w=tw+16; r.h=1; SDL_FillRect(screen,&r,0x0F);
  r.w=1; r.h=th+16; SDL_FillRect(screen,&r,0x0F);
  r.x++; r.y++;
  r.w=tw+14; r.h=1; SDL_FillRect(screen,&r,0x0D);
  r.w=1; r.h=th+14; SDL_FillRect(screen,&r,0x0D);
  r.x++; r.y++;
  r.w=tw+12; r.h=1; SDL_FillRect(screen,&r,0x0B);
  r.w=1; r.h=th+12; SDL_FillRect(screen,&r,0x0B);
  r.x=bx+tw+15; r.y=by;
  r.w=1; r.h=th+16; SDL_FillRect(screen,&r,0x02);
  r.x--; r.y++; r.h-=2; SDL_FillRect(screen,&r,0x05);
  r.x--; r.y++; r.h-=2; SDL_FillRect(screen,&r,0x08);
  r.x=bx; r.y=by+th+15;
  r.w=tw+16; r.h=1; SDL_FillRect(screen,&r,0x02);
  r.x++; r.y--; r.w-=2; SDL_FillRect(screen,&r,0x05);
  r.x++; r.y--; r.w-=2; SDL_FillRect(screen,&r,0x08);
  // Draw text
  bx+=8; by+=8; tw-=8; th-=8;
  x=bx; y=by;
  c=colo[0];
  ln=0;
  SDL_LockSurface(screen);
  while(*p && ln<64 && y+li[ln].h<screen->h) switch(*p++) {
    case 1 ... 8:
      c=colo[p[-1]-1];
      break;
    case 10:
      y+=li[ln++].h;
      if(ln<64) x=li[ln].a?bx+(tw-li[ln].w)/2:bx;
      break;
    case 11:
      // do nothing
      break;
    case 12:
      if(x==bx) x+=(tw-li[ln].w)/2;
      break;
    case 14:
      pop_image(x,y,li+ln,p);
      x+=picture_size;
      p=strchr(p,'\\')?:"";
      if(*p) p++;
      break;
    case 15:
      y+=li[ln++].h;
      pop_bar(bx,y,li+ln,tw);
      y+=8;
      if(ln<64) x=li[ln].a?bx+(tw-li[ln].w)/2:bx;
      break;
    case 16:
      pop_quiz(x,y,li+ln,c,*p);
      if(*p) p++;
      x+=24;
      break;
    case 31:
      pop_char(x,y,li+ln,c,*p);
      if(*p) p++;
      x+=8;
    default:
      pop_char(x,y,li+ln,c,p[-1]);
      x+=8;
      break;
  }
  SDL_UnlockSurface(screen);
}

int modal_draw_popup(const unsigned char*txt) {
  SDL_Event ev;
  SDL_Rect r;
  r.x=r.y=0;
  r.w=screen->w;
  r.h=4;
  SDL_FillRect(screen,&r,0xFE);
  set_cursor(XC_iron_cross);
  redraw:
  draw_popup(txt);
  SDL_Flip(screen);
  while(SDL_WaitEvent(&ev)) switch(ev.type) {
    case SDL_QUIT:
      SDL_PushEvent(&ev);
      return -1;
    case SDL_KEYDOWN:
      switch(ev.key.keysym.sym) {
        case SDLK_RETURN: case SDLK_KP_ENTER: case SDLK_ESCAPE:
          return 0;
      }
      break;
    case SDL_MOUSEBUTTONDOWN:
      return 0;
    case SDL_VIDEOEXPOSE:
      goto redraw;
  }
  return -1;
}