map2stl.diff, add gcc support

*** map2stl.c   2009-05-15 20:53:30.000000000 +0400
--- my_map2stl.c    2014-10-31 13:14:47.469190278 +0400
***************
*** 24,36 ****
  typedef struct
  {
     short wallptr, wallnum;
!    long z[2]; short stat[2]; build7surf_t surf[2];
     char visibility, filler;
     short lotag, hitag, extra;
  } build7sect_t;
  typedef struct
  {
!    long x, y;
     short point2, nextwall, nextsect, cstat, picnum, overpicnum;
     signed char shade;
     char pal, xrepeat, yrepeat, xpanning, ypanning;
--- 24,36 ----
  typedef struct
  {
     short wallptr, wallnum;
!    int  z[2]; short stat[2]; build7surf_t surf[2];
     char visibility, filler;
     short lotag, hitag, extra;
  } build7sect_t;
  typedef struct
  {
!    int x, y;
     short point2, nextwall, nextsect, cstat, picnum, overpicnum;
     signed char shade;
     char pal, xrepeat, yrepeat, xpanning, ypanning;
***************
*** 349,368 ****
  static long loadmap (char *filnam)
  {
     float f, fx, fy;
!    long i, j, k;
     short s;
     FILE *fil;
!
!    fil = fopen(filnam,"rb"); if (!fil) return(0);
!    fread(&i,4,1,fil); if (i != 0x00000007) return(0); //not Build1 .MAP format 7
     fseek(fil,20,SEEK_SET);

!    fread(&s,2,1,fil); numsects = (long)s;
     sec = (sect_t *)malloc(numsects*sizeof(sect_t));
     memset(sec,0,numsects*sizeof(sect_t));
     for(i=0;i<numsects;i++)
     {
!       fread(&b7sec,sizeof(b7sec),1,fil);
        sec[i].n = b7sec.wallnum;
        sec[i].wall = (wall_t *)realloc(sec[i].wall,sec[i].n*sizeof(wall_t));
        memset(sec[i].wall,0L,sec[i].n*sizeof(wall_t));
--- 349,379 ----
  static long loadmap (char *filnam)
  {
     float f, fx, fy;
!    int i;
!    long  j, k;
     short s;
     FILE *fil;
!    fil = fopen(filnam,"rb");
!    if (fil == NULL)
!   return(0);
!    if (fread(&i,1, sizeof(i),fil) != 4)
!   return(0);
!
!    if (i != 7 && i !=9)
!   return(0); //not Build1 .MAP format 7
     fseek(fil,20,SEEK_SET);

!    if (fread(&s,1,sizeof(s),fil) != 2)
!   return(0);
!
!    numsects = (long)s;
     sec = (sect_t *)malloc(numsects*sizeof(sect_t));
     memset(sec,0,numsects*sizeof(sect_t));
     for(i=0;i<numsects;i++)
     {
!       if (fread(&b7sec,1,sizeof(b7sec),fil) != 40) // read sectors
!   return(0);
!
        sec[i].n = b7sec.wallnum;
        sec[i].wall = (wall_t *)realloc(sec[i].wall,sec[i].n*sizeof(wall_t));
        memset(sec[i].wall,0L,sec[i].n*sizeof(wall_t));
***************
*** 375,394 ****
        }
     }

!    fread(&s,2,1,fil); //numwalls
     for(i=k=0;i<numsects;i++)
     {
        for(j=0;j<sec[i].n;j++,k++)
        {
!          fread(&b7wal,sizeof(b7wal),1,fil);
           sec[i].wall[j].x = ((float)b7wal.x)*(1.f/512.f);
           sec[i].wall[j].y = ((float)b7wal.y)*(1.f/512.f);
           sec[i].wall[j].n = b7wal.point2-k;
        }
!
        fx = sec[i].wall[1].y-sec[i].wall[0].y;
        fy = sec[i].wall[0].x-sec[i].wall[1].x;
!       f = fx*fx + fy*fy; if (f > 0.f) f = 1.f/(float)sqrt(f); fx *= f; fy *= f;
        for(j=0;j<2;j++)
        {
           sec[i].grad[j].x = fx*sec[i].grad[j].y;
--- 386,414 ----
        }
     }

!    if (fread(&s,1,2,fil) != 2)
!   return(0); // walls  count
!
     for(i=k=0;i<numsects;i++)
     {
        for(j=0;j<sec[i].n;j++,k++)
        {
!          if (fread(&b7wal,1, sizeof(b7wal),fil) != 32) //read walls
!       return(0);
!
           sec[i].wall[j].x = ((float)b7wal.x)*(1.f/512.f);
           sec[i].wall[j].y = ((float)b7wal.y)*(1.f/512.f);
           sec[i].wall[j].n = b7wal.point2-k;
        }
!
        fx = sec[i].wall[1].y-sec[i].wall[0].y;
        fy = sec[i].wall[0].x-sec[i].wall[1].x;
!
!       f = fx*fx + fy*fy;
!       if (f > 0.f)
!   f = 1.f/(float)sqrt(f);
!       fx *= f; fy *= f;
!
        for(j=0;j<2;j++)
        {
           sec[i].grad[j].x = fx*sec[i].grad[j].y;