Free Hero Mesh

typedef struct {
  Uint8 shift[32];
  Uint8 size[32];
  Uint8 nshift;
} ShiftFilter;

typedef struct {
  Uint8 hue;
  Sint8 shade;
} HueShadeFilter;

typedef struct {
  Uint8 code;
  // 0-7 = flip/rotations
  // 8-10 = change colours (8 is *->* *->* *->*; 9 is *->*->*->*->*; 10 is *<->* *<->* *<->*)
  // 11 = overlay
  // 12-15 = shift (up, down, right, left)
  // 16 = hue/shade
  union {
    ColorFilter color;
    OverlayFilter overlay;
    ShiftFilter shift;
    HueShadeFilter hueshade;
  };
} Filter;

typedef struct {
  union {
    char basename[64];
    struct {

        for(k=0;k<64;k++) {
          dp->filters[i].shift.shift[k]=(j=fgetc(fp))&127;
          dp->filters[i].shift.size[k]=fgetc(fp);
          if(j&128) break;
        }
        dp->filters[i].shift.nshift=k+1;
        break;
      case 16:
        dp->filters[i].hueshade.hue=fgetc(fp);
        dp->filters[i].hueshade.shade=(Sint8)fgetc(fp);
        break;
    }
  }
  fclose(fp);
}

static void save_dependent_picture(FILE*fp,DependentPicture*dp,int mode) {
  int i,j;

      case 12 ... 15:
        if(!dp->filters[i].shift.nshift) fwrite("\x80",1,2,fp);
        for(j=0;j<dp->filters[i].shift.nshift;j++) {
          fputc(dp->filters[i].shift.shift[j]|(j==dp->filters[i].shift.nshift-1?128:0),fp);
          fputc(dp->filters[i].shift.size[j],fp);
        }
        break;
      case 16:
        fputc(dp->filters[i].hueshade.hue,fp);
        fputc(dp->filters[i].hueshade.shade,fp);
        break;
    }
  }
}

static int add_filter(DependentPicture*dp,const char*const*const txt,Sint8 c) {
  SDL_Rect r;
  SDL_Event ev;
  Uint8 f;
  char buf[4]="<?>";
  if(c<0 || dp->nfilters>63) return;
  r.x=r.y=12; r.w=200; r.h=144;
  set_cursor(XC_iron_cross);
  redraw:
  SDL_LockSurface(screen);
  SDL_FillRect(screen,&r,0xF8);
  for(f=0;f<17;f++) {
    buf[1]=f+'a';
    draw_text(16,(f+2)<<3,buf,0xF8,0xFB);
    draw_text(48,(f+2)<<3,txt[f],0xF8,0xFF);
  }
  SDL_UnlockSurface(screen);
  SDL_Flip(screen);
  while(SDL_WaitEvent(&ev)) switch(ev.type) {
    case SDL_QUIT: exit(0); return 0;
    case SDL_KEYDOWN:
      if(ev.key.keysym.sym==SDLK_ESCAPE || ev.key.keysym.sym==SDLK_z) return 0;
      if(ev.key.keysym.sym<SDLK_a || ev.key.keysym.sym>SDLK_q) break;
      f=ev.key.keysym.sym-SDLK_a;
      goto found;
    case SDL_VIDEOEXPOSE: goto redraw;
  }
  found:
  ++dp->nfilters;
  if(c!=63) memmove(dp->filters+c+1,dp->filters+c,(63-c)*sizeof(Filter));

      }
      goto redraw;
    case SDL_VIDEOEXPOSE: goto redraw;
  }
}

static void edit_dependent_picture(DependentPicture*dp,const char*name) {
  static const char*const txt[17]={
    "Identity",
    "Flip \x1D",
    "Flip \x12",
    "Rotate 180\xF8",
    "Transpose",
    "Transposed flip \x1D",
    "Transposed flip \x12",
    "Reverse Transpose",
    "Replace colors",
    "Advance colors",
    "Exchange colors",
    "Overlay",
    "Shift \x18",
    "Shift \x19",
    "Shift \x1A",
    "Shift \x1B",
    "Hue/Shade",
  };
  const char*s;
  char buf[64];
  Sint8 c=-1;
  int i,j,y;
  SDL_Rect r;
  SDL_Event ev;

        draw_text(16,y,txt[j],0xF0,0xF7);
        y+=8;
        for(j=0;j<dp->filters[i].shift.nshift;j++) {
          snprintf(buf,64,"%d: %d",dp->filters[i].shift.size[j],dp->filters[i].shift.shift[j]);
          draw_text(32,y,buf,0xF0,0xFE);
          y+=8;
        }
        break;
      case 16:
        draw_text(16,y,"Hue/Shade: ",0xF0,0xF7);
        snprintf(buf,64,"%d %+d",dp->filters[i].hueshade.hue,dp->filters[i].hueshade.shade);
        draw_text(104,y,buf,0xF0,0xFE);
        y+=8;
        break;
      default:
        draw_text(16,y,"???",0xF0,0xFC);
        y+=8;
        break;
    }
  }

                  break;
                case 11:
                  s=screen_prompt("Name of overlay picture:");
                  if(s && *s) strncpy(dp->filters[c].overlay.name,s,63);
                  break;
                case 12 ... 15:
                  edit_shift_filter(&dp->filters[c].shift);
                  break;
                case 16:
                  s=screen_prompt("Hue adjust:");
                  if(s && *s) {
                    i=strtol(s,0,10);
                    s=screen_prompt("Shade adjust:");
                    if(s && *s) {
                      dp->filters[c].hueshade.hue=i;
                      dp->filters[c].hueshade.shade=strtol(s,0,10);
                    }
                  }
                  break;
              }
            }
            break;
          case SDLK_DELETE: case SDLK_KP_PERIOD:
            if(c<0 || c>=dp->nfilters) break;
            --dp->nfilters;