support "extended nodes"

This converts some variables to their unsidged types, which enables
the port to load all maps which use the regular Doom BSP nodes format.

This enables the port to load some maps that it would normally choke
upon, e.g. Nova Maps 30 and 31; Eviternity Map 15 and Sunlust Maps 16,
18, 20, 24, 28 and 31.

It does still not support DeePBSP and ZDBSP nodes, and will probably
never do.

Fixes #23.

Source/doomdata.h

@@ -75,12 +75,12 @@ typedef struct {
 // A LineDef, as used for editing, and as input to the BSP builder.
 
 typedef struct {
-  short v1;
-  short v2;
-  short flags;
+  unsigned short v1;
+  unsigned short v2;
+  unsigned short flags;
   short special;
   short tag;
-  short sidenum[2];  // sidenum[1] will be -1 if one sided
+  unsigned short sidenum[2];  // sidenum[1] will be -1 (NO_INDEX) if one sided
 } maplinedef_t;
 
 //
@@ -140,17 +140,17 @@ typedef struct {
 
 // SubSector, as generated by BSP.
 typedef struct {
-  short numsegs;
-  short firstseg;    // Index of first one; segs are stored sequentially.
+  unsigned short numsegs;
+  unsigned short firstseg;    // Index of first one; segs are stored sequentially.
 } mapsubsector_t;
 
 // LineSeg, generated by splitting LineDefs
 // using partition lines selected by BSP builder.
 typedef struct {
-  short v1;
-  short v2;
+  unsigned short v1;
+  unsigned short v2;
   short angle;
-  short linedef;
+  unsigned short linedef;
   short side;
   short offset;
 } mapseg_t;
@@ -158,7 +158,9 @@ typedef struct {
 // BSP node structure.
 
 // Indicate a leaf.
-#define NF_SUBSECTOR    0x8000
+#define NF_SUBSECTOR    0x80000000
+ // [FG] extended nodes
+#define NO_INDEX        ((unsigned short)-1)
 
 typedef struct {
   short x;  // Partition line from (x,y) to x+dx,y+dy)

Source/p_doors.c

@@ -439,7 +439,7 @@ int EV_VerticalDoor(line_t *line, mobj_t *thing)
     }
 
   // if the wrong side of door is pushed, give oof sound
-  if (line->sidenum[1]==-1)                       // killough
+  if (line->sidenum[1]==NO_INDEX)                       // killough
     {
       S_StartSound(player->mo,sfx_oof);           // killough 3/20/98
       return 0;

Source/p_maputl.c

@@ -160,7 +160,7 @@ sector_t *openbacksector;  // made global
 
 void P_LineOpening(line_t *linedef)
 {
-  if (linedef->sidenum[1] == -1)      // single sided line
+  if (linedef->sidenum[1] == NO_INDEX)      // single sided line
     {
       openrange = 0;
       return;

Source/p_saveg.c

@@ -115,10 +115,10 @@ void P_ArchiveWorld (void)
 
   for (i=0; i<numlines; i++)
     {
-      if (lines[i].sidenum[0] != -1)
+      if (lines[i].sidenum[0] != NO_INDEX)
         size +=
 	  sizeof(short)*3 + sizeof si->textureoffset + sizeof si->rowoffset;
-      if (lines[i].sidenum[1] != -1)
+      if (lines[i].sidenum[1] != NO_INDEX)
 	size +=
 	  sizeof(short)*3 + sizeof si->textureoffset + sizeof si->rowoffset;
     }
@@ -155,7 +155,7 @@ void P_ArchiveWorld (void)
       *put++ = li->tag;
 
       for (j=0; j<2; j++)
-        if (li->sidenum[j] != -1)
+        if (li->sidenum[j] != NO_INDEX)
           {
 	    si = &sides[li->sidenum[j]];
 
@@ -221,7 +221,7 @@ void P_UnArchiveWorld (void)
       li->special = *get++;
       li->tag = *get++;
       for (j=0 ; j<2 ; j++)
-        if (li->sidenum[j] != -1)
+        if (li->sidenum[j] != NO_INDEX)
           {
             side_t *si = &sides[li->sidenum[j]];
 

Source/p_setup.c

@@ -164,12 +164,12 @@ void P_LoadSegs (int lump)
       int side, linedef;
       line_t *ldef;
 
-      li->v1 = &vertexes[SHORT(ml->v1)];
-      li->v2 = &vertexes[SHORT(ml->v2)];
+      li->v1 = &vertexes[(unsigned short)SHORT(ml->v1)];
+      li->v2 = &vertexes[(unsigned short)SHORT(ml->v2)];
 
       li->angle = (SHORT(ml->angle))<<16;
       li->offset = (SHORT(ml->offset))<<16;
-      linedef = SHORT(ml->linedef);
+      linedef = (unsigned short)SHORT(ml->linedef);
       ldef = &lines[linedef];
       li->linedef = ldef;
       side = SHORT(ml->side);
@@ -177,7 +177,7 @@ void P_LoadSegs (int lump)
       li->frontsector = sides[ldef->sidenum[side]].sector;
 
       // killough 5/3/98: ignore 2s flag if second sidedef missing:
-      if (ldef->flags & ML_TWOSIDED && ldef->sidenum[side^1]!=-1)
+      if (ldef->flags & ML_TWOSIDED && ldef->sidenum[side^1]!=NO_INDEX)
         li->backsector = sides[ldef->sidenum[side^1]].sector;
       else
 	li->backsector = 0;
@@ -204,8 +204,8 @@ void P_LoadSubsectors (int lump)
 
   for (i=0; i<numsubsectors; i++)
     {
-      subsectors[i].numlines  = SHORT(((mapsubsector_t *) data)[i].numsegs );
-      subsectors[i].firstline = SHORT(((mapsubsector_t *) data)[i].firstseg);
+      subsectors[i].numlines  = (unsigned short)SHORT(((mapsubsector_t *) data)[i].numsegs );
+      subsectors[i].firstline = (unsigned short)SHORT(((mapsubsector_t *) data)[i].firstseg);
     }
 
   Z_Free (data);
@@ -296,7 +296,22 @@ void P_LoadNodes (int lump)
       for (j=0 ; j<2 ; j++)
         {
           int k;
-          no->children[j] = SHORT(mn->children[j]);
+          no->children[j] = (unsigned short)SHORT(mn->children[j]);
+
+          // [FG] extended nodes
+          if (no->children[j] == 0xFFFF)
+              no->children[j] = -1;
+          else
+          if (no->children[j] & 0x8000)
+          {
+              no->children[j] &= ~0x8000;
+
+               if (no->children[j] >= numsubsectors)
+                  no->children[j] = 0;
+
+               no->children[j] |= NF_SUBSECTOR;
+          }
+
           for (k=0 ; k<4 ; k++)
             no->bbox[j][k] = SHORT(mn->bbox[j][k])<<FRACBITS;
         }
@@ -377,11 +392,11 @@ void P_LoadLineDefs (int lump)
       line_t *ld = lines+i;
       vertex_t *v1, *v2;
 
-      ld->flags = SHORT(mld->flags);
+      ld->flags = (unsigned short)SHORT(mld->flags);
       ld->special = SHORT(mld->special);
       ld->tag = SHORT(mld->tag);
-      v1 = ld->v1 = &vertexes[SHORT(mld->v1)];
-      v2 = ld->v2 = &vertexes[SHORT(mld->v2)];
+      v1 = ld->v1 = &vertexes[(unsigned short)SHORT(mld->v1)];
+      v2 = ld->v2 = &vertexes[(unsigned short)SHORT(mld->v2)];
       ld->dx = v2->x - v1->x;
       ld->dy = v2->y - v1->y;
 
@@ -416,7 +431,7 @@ void P_LoadLineDefs (int lump)
       ld->sidenum[1] = SHORT(mld->sidenum[1]);
 
       // killough 4/4/98: support special sidedef interpretation below
-      if (ld->sidenum[0] != -1 && ld->special)
+      if (ld->sidenum[0] != NO_INDEX && ld->special)
         sides[*ld->sidenum].special = ld->special;
     }
   Z_Free (data);
@@ -433,14 +448,14 @@ void P_LoadLineDefs2(int lump)
     {
       // killough 11/98: fix common wad errors (missing sidedefs):
 
-      if (ld->sidenum[0] == -1)
+      if (ld->sidenum[0] == NO_INDEX)
 	ld->sidenum[0] = 0;  // Substitute dummy sidedef for missing right side
 
-      if (ld->sidenum[1] == -1)
+      if (ld->sidenum[1] == NO_INDEX)
 	ld->flags &= ~ML_TWOSIDED;  // Clear 2s flag for missing left side
 
-      ld->frontsector = ld->sidenum[0]!=-1 ? sides[ld->sidenum[0]].sector : 0;
-      ld->backsector  = ld->sidenum[1]!=-1 ? sides[ld->sidenum[1]].sector : 0;
+      ld->frontsector = ld->sidenum[0]!=NO_INDEX ? sides[ld->sidenum[0]].sector : 0;
+      ld->backsector  = ld->sidenum[1]!=NO_INDEX ? sides[ld->sidenum[1]].sector : 0;
       switch (ld->special)
         {                       // killough 4/11/98: handle special types
           int lump, j;

Source/p_spec.c

@@ -214,7 +214,7 @@ int twoSided(int sector, int line)
   //has two sidedefs, rather than whether the 2S flag is set
 
   return comp[comp_model] ? sectors[sector].lines[line]->flags & ML_TWOSIDED :
-    sectors[sector].lines[line]->sidenum[1] != -1;
+    sectors[sector].lines[line]->sidenum[1] != NO_INDEX;
 }
 
 //

Source/r_defs.h

@@ -181,10 +181,10 @@ typedef struct line_s
 {
   vertex_t *v1, *v2;     // Vertices, from v1 to v2.
   fixed_t dx, dy;        // Precalculated v2 - v1 for side checking.
-  short flags;           // Animation related.
+  unsigned short flags;           // Animation related.
   short special;         
   short tag;
-  short sidenum[2];      // Visual appearance: SideDefs.
+  unsigned short sidenum[2];      // Visual appearance: SideDefs.
   fixed_t bbox[4];       // A bounding box, for the linedef's extent
   slopetype_t slopetype; // To aid move clipping.
   sector_t *frontsector; // Front and back sector.
@@ -206,7 +206,7 @@ typedef struct line_s
 typedef struct subsector_s
 {
   sector_t *sector;
-  short numlines, firstline;
+  int numlines, firstline;
 } subsector_t;
 
 // phares 3/14/98
@@ -262,7 +262,7 @@ typedef struct
 {
   fixed_t  x,  y, dx, dy;        // Partition line.
   fixed_t bbox[2][4];            // Bounding box for each child.
-  unsigned short children[2];    // If NF_SUBSECTOR its a subsector.
+  int children[2];    // If NF_SUBSECTOR its a subsector.
 } node_t;
 
 // posts are runs of non masked source pixels