Patch #2969 - Doom! Currently only working on the H300.

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@9312 a1c6a512-1295-4272-9138-f99709370657

1 files changed, 976 insertions, 0 deletions

diff --git a/apps/plugins/doom/r_things.c b/apps/plugins/doom/r_things.c
new file mode 100644
index 0000000000..2e1f72e34c
--- /dev/null
+++ b/apps/plugins/doom/r_things.c
@@ -0,0 +1,976 @@
+/* Emacs style mode select   -*- C++ -*-
+ *-----------------------------------------------------------------------------
+ *
+ *
+ *  PrBoom a Doom port merged with LxDoom and LSDLDoom
+ *  based on BOOM, a modified and improved DOOM engine
+ *  Copyright (C) 1999 by
+ *  id Software, Chi Hoang, Lee Killough, Jim Flynn, Rand Phares, Ty Halderman
+ *  Copyright (C) 1999-2000 by
+ *  Jess Haas, Nicolas Kalkhof, Colin Phipps, Florian Schulze
+ *
+ *  This program is free software; you can redistribute it and/or
+ *  modify it under the terms of the GNU General Public License
+ *  as published by the Free Software Foundation; either version 2
+ *  of the License, or (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to the Free Software
+ *  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+ *  02111-1307, USA.
+ *
+ * DESCRIPTION:
+ *  Refresh of things, i.e. objects represented by sprites.
+ *
+ *-----------------------------------------------------------------------------*/
+
+#include "doomdef.h"
+#include "m_swap.h"
+
+#include "doomstat.h"
+#include "w_wad.h"
+#include "r_main.h"
+#include "r_bsp.h"
+#include "r_segs.h"
+#include "r_draw.h"
+#include "r_things.h"
+#include "i_system.h"
+//#include "lprintf.h"
+#include "rockmacros.h"
+
+#define MINZ    (FRACUNIT*4)
+#define BASEYCENTER   100
+
+typedef struct {
+   int x1;
+   int x2;
+   int column;
+   int topclip;
+   int bottomclip;
+} maskdraw_t;
+
+//
+// Sprite rotation 0 is facing the viewer,
+//  rotation 1 is one angle turn CLOCKWISE around the axis.
+// This is not the same as the angle,
+//  which increases counter clockwise (protractor).
+// There was a lot of stuff grabbed wrong, so I changed it...
+//
+fixed_t  pspritescale;
+fixed_t  pspriteiscale;
+
+static lighttable_t** spritelights;
+
+// constant arrays
+//  used for psprite clipping and initializing clipping
+short  negonearray[SCREENWIDTH];
+short  screenheightarray[SCREENWIDTH];
+
+
+//
+// INITIALIZATION FUNCTIONS
+//
+
+// variables used to look up and range check thing_t sprites patches
+
+spritedef_t* sprites;
+int  numsprites;
+
+#define MAX_SPRITE_FRAMES 29          /* Macroized -- killough 1/25/98 */
+
+static spriteframe_t sprtemp[MAX_SPRITE_FRAMES];
+static int maxframe;
+
+//
+// R_InstallSpriteLump
+// Local function for R_InitSprites.
+//
+
+static void R_InstallSpriteLump(int lump, unsigned frame,
+                                unsigned rotation, boolean flipped)
+{
+
+  if (frame >= MAX_SPRITE_FRAMES || rotation > 8)
+    I_Error("R_InstallSpriteLump: Bad frame characters in lump %i", lump);
+
+   if ((int)frame > maxframe)
+      maxframe = frame;
+
+  if (rotation == 0)
+    {    // the lump should be used for all rotations
+      int r;
+      for (r=0 ; r<8 ; r++)
+        if (sprtemp[frame].lump[r]==-1)
+          {
+            sprtemp[frame].lump[r] = lump - firstspritelump;
+            sprtemp[frame].flip[r] = (byte) flipped;
+            sprtemp[frame].rotate = false; //jff 4/24/98 if any subbed, rotless
+          }
+      return;
+    }
+
+  // the lump is only used for one rotation
+
+  if (sprtemp[frame].lump[--rotation] == -1)
+    {
+      sprtemp[frame].lump[rotation] = lump - firstspritelump;
+      sprtemp[frame].flip[rotation] = (byte) flipped;
+      sprtemp[frame].rotate = true; //jff 4/24/98 only change if rot used
+    }
+}
+
+//
+// R_InitSpriteDefs
+// Pass a null terminated list of sprite names
+// (4 chars exactly) to be used.
+//
+// Builds the sprite rotation matrixes to account
+// for horizontally flipped sprites.
+//
+// Will report an error if the lumps are inconsistent.
+// Only called at startup.
+//
+// Sprite lump names are 4 characters for the actor,
+//  a letter for the frame, and a number for the rotation.
+//
+// A sprite that is flippable will have an additional
+//  letter/number appended.
+//
+// The rotation character can be 0 to signify no rotations.
+//
+// 1/25/98, 1/31/98 killough : Rewritten for performance
+//
+// Empirically verified to have excellent hash
+// properties across standard Doom sprites:
+
+#define R_SpriteNameHash(s) ((unsigned)((s)[0]-((s)[1]*3-(s)[3]*2-(s)[2])*2))
+
+void R_InitSpriteDefs(const char * const * namelist)
+{
+  size_t numentries = lastspritelump-firstspritelump+1;
+  struct { int index, next; } *hash;
+  int i;
+
+  if (!numentries || !*namelist)
+    return;
+
+  // count the number of sprite names
+  for (i=0; namelist[i]; i++)
+    ;
+
+  numsprites = i;
+
+  sprites = Z_Malloc(numsprites *sizeof(*sprites), PU_STATIC, NULL);
+
+  // Create hash table based on just the first four letters of each sprite
+  // killough 1/31/98
+
+  hash = malloc(sizeof(*hash)*numentries); // allocate hash table
+
+  for (i=0; (size_t)i<numentries; i++)             // initialize hash table as empty
+    hash[i].index = -1;
+
+  for (i=0; (size_t)i<numentries; i++)             // Prepend each sprite to hash chain
+    {                                      // prepend so that later ones win
+      int j = R_SpriteNameHash(lumpinfo[i+firstspritelump].name) % numentries;
+      hash[i].next = hash[j].index;
+      hash[j].index = i;
+    }
+
+  // scan all the lump names for each of the names,
+  //  noting the highest frame letter.
+
+  for (i=0 ; i<numsprites ; i++)
+    {
+      const char *spritename = namelist[i];
+      int j = hash[R_SpriteNameHash(spritename) % numentries].index;
+
+      if (j >= 0)
+        {
+          memset(sprtemp, -1, sizeof(sprtemp));
+          maxframe = -1;
+          do
+            {
+              register lumpinfo_t *lump = lumpinfo + j + firstspritelump;
+
+              // Fast portable comparison -- killough
+              // (using int pointer cast is nonportable):
+
+              if (!((lump->name[0] ^ spritename[0]) |
+                    (lump->name[1] ^ spritename[1]) |
+                    (lump->name[2] ^ spritename[2]) |
+                    (lump->name[3] ^ spritename[3])))
+                {
+                  R_InstallSpriteLump(j+firstspritelump,
+                                      lump->name[4] - 'A',
+                                      lump->name[5] - '0',
+                                      false);
+                  if (lump->name[6])
+                    R_InstallSpriteLump(j+firstspritelump,
+                                        lump->name[6] - 'A',
+                                        lump->name[7] - '0',
+                                        true);
+                }
+            }
+          while ((j = hash[j].next) >= 0);
+
+          // check the frames that were found for completeness
+          if ((sprites[i].numframes = ++maxframe))  // killough 1/31/98
+            {
+              int frame;
+              for (frame = 0; frame < maxframe; frame++)
+                switch ((int) sprtemp[frame].rotate)
+                  {
+                  case -1:
+                    // no rotations were found for that frame at all
+                    I_Error ("R_InitSprites: No patches found "
+                             "for %.8s frame %c", namelist[i], frame+'A');
+                    break;
+
+                  case 0:
+                    // only the first rotation is needed
+                    break;
+
+                  case 1:
+                    // must have all 8 frames
+                    {
+                      int rotation;
+                      for (rotation=0 ; rotation<8 ; rotation++)
+                        if (sprtemp[frame].lump[rotation] == -1)
+                          I_Error ("R_InitSprites: Sprite %.8s frame %c "
+                                   "is missing rotations",
+                                   namelist[i], frame+'A');
+                      break;
+                    }
+                  }
+              // allocate space for the frames present and copy sprtemp to it
+              sprites[i].spriteframes =
+                Z_Malloc (maxframe * sizeof(spriteframe_t), PU_STATIC, NULL);
+              memcpy (sprites[i].spriteframes, sprtemp,
+                      maxframe*sizeof(spriteframe_t));
+            }
+        }
+    }
+   free(hash);             // free hash table
+}
+
+//
+// GAME FUNCTIONS
+//
+
+static vissprite_t *vissprites, **vissprite_ptrs;  // killough
+static size_t num_vissprite, num_vissprite_alloc, num_vissprite_ptrs;
+
+
+//
+// R_InitSprites
+// Called at program start.
+//
+void R_InitSprites(const char * const *namelist)
+{
+   int  i;
+
+   for (i=0 ; i<SCREENWIDTH ; i++)
+      negonearray[i] = -1;
+   R_InitSpriteDefs (namelist);
+}
+
+void R_ClearSprites (void)
+{
+   num_vissprite = 0;            // killough
+}
+
+//
+// R_NewVisSprite
+//
+
+vissprite_t *R_NewVisSprite(void)
+{
+   if (num_vissprite >= num_vissprite_alloc)             // killough
+   {
+      num_vissprite_alloc = num_vissprite_alloc ? num_vissprite_alloc*2 : 128;
+      vissprites = realloc(vissprites,num_vissprite_alloc*sizeof(*vissprites));
+   }
+   return vissprites + num_vissprite++;
+}
+
+//
+// R_DrawMaskedColumn
+// Used for sprites and masked mid textures.
+// Masked means: partly transparent, i.e. stored
+//  in posts/runs of opaque pixels.
+//
+
+short*  mfloorclip;
+short*  mceilingclip;
+fixed_t  spryscale;
+fixed_t  sprtopscreen;
+
+void R_DrawMaskedColumn(const column_t *column)
+{
+  int     topscreen;
+  int     bottomscreen;
+  fixed_t basetexturemid = dc_texturemid;
+
+  dc_texheight = 0; // killough 11/98
+  while (column->topdelta != 0xff)
+    {
+      // calculate unclipped screen coordinates for post
+      topscreen = sprtopscreen + spryscale*column->topdelta;
+      bottomscreen = topscreen + spryscale*column->length;
+
+      dc_yl = (topscreen+FRACUNIT-1)>>FRACBITS;
+      dc_yh = (bottomscreen-1)>>FRACBITS;
+
+      if (dc_yh >= mfloorclip[dc_x])
+        dc_yh = mfloorclip[dc_x]-1;
+
+      if (dc_yl <= mceilingclip[dc_x])
+        dc_yl = mceilingclip[dc_x]+1;
+
+      // killough 3/2/98, 3/27/98: Failsafe against overflow/crash:
+      if (dc_yl <= dc_yh && dc_yh < viewheight)
+        {
+          dc_source = (byte *)column + 3;
+          dc_texturemid = basetexturemid - (column->topdelta<<FRACBITS);
+
+          // Drawn by either R_DrawColumn
+          //  or (SHADOW) R_DrawFuzzColumn.
+          colfunc ();
+        }
+      column = (const column_t *)(  (byte *)column + column->length + 4);
+    }
+  dc_texturemid = basetexturemid;
+}
+
+//
+// R_DrawVisSprite
+//  mfloorclip and mceilingclip should also be set.
+//
+// CPhipps - new wad lump handling, *'s to const*'s
+void R_DrawVisSprite(vissprite_t *vis, int x1, int x2)
+{
+   (void)x1;
+   (void)x2;
+   const column_t *column;
+   int      texturecolumn;
+   fixed_t  frac;
+   const patch_t *patch = W_CacheLumpNum (vis->patch+firstspritelump);
+
+   dc_colormap = vis->colormap;
+
+   // killough 4/11/98: rearrange and handle translucent sprites
+   // mixed with translucent/non-translucenct 2s normals
+
+   if (!dc_colormap)   // NULL colormap = shadow draw
+      colfunc = R_DrawFuzzColumn;    // killough 3/14/98
+   else
+      if (vis->mobjflags & MF_TRANSLATION)
+      {
+         colfunc = R_DrawTranslatedColumn;
+         dc_translation = translationtables - 256 +
+                          ((vis->mobjflags & MF_TRANSLATION) >> (MF_TRANSSHIFT-8) );
+      }
+      else
+         if (vis->mobjflags & MF_TRANSLUCENT && general_translucency) // phares
+         {
+            colfunc = R_DrawTLColumn;
+            tranmap = main_tranmap;       // killough 4/11/98
+         }
+         else
+            colfunc = R_DrawColumn;         // killough 3/14/98, 4/11/98
+            
+
+   // proff 11/06/98: Changed for high-res
+   dc_iscale = D_abs(vis->xiscale);
+   dc_texturemid = vis->texturemid;
+   frac = vis->startfrac;
+   spryscale = vis->scale;
+   sprtopscreen = centeryfrac - FixedMul(dc_texturemid,spryscale);
+
+   for (dc_x=vis->x1 ; dc_x<=vis->x2 ; dc_x++, frac += vis->xiscale)
+   {
+      texturecolumn = frac>>FRACBITS;
+
+#ifdef RANGECHECK
+      if (texturecolumn < 0 || texturecolumn >= SHORT(patch->width))
+         I_Error ("R_DrawSpriteRange: Bad texturecolumn");
+#endif
+
+      column = (const column_t *)((const byte *) patch +
+                                  LONG(patch->columnofs[texturecolumn]));
+      R_DrawMaskedColumn (column);
+   }
+   colfunc = R_DrawColumn;         // killough 3/14/98
+   W_UnlockLumpNum(vis->patch+firstspritelump); // cph - release lump
+}
+
+//
+// R_ProjectSprite
+// Generates a vissprite for a thing if it might be visible.
+//
+
+void R_ProjectSprite (mobj_t* thing)
+{
+   fixed_t   gzt;               // killough 3/27/98
+   fixed_t   tx;
+   fixed_t   xscale;
+   int       x1;
+   int       x2;
+   spritedef_t   *sprdef;
+   spriteframe_t *sprframe;
+   int       lump;
+   boolean   flip;
+   vissprite_t *vis;
+#ifndef GL_DOOM
+   fixed_t   iscale;
+#endif
+   int heightsec;      // killough 3/27/98
+
+   // transform the origin point
+   fixed_t tr_x = thing->x - viewx;
+   fixed_t tr_y = thing->y - viewy;
+
+   fixed_t gxt = FixedMul(tr_x,viewcos);
+   fixed_t gyt = -FixedMul(tr_y,viewsin);
+
+   fixed_t tz = gxt-gyt;
+
+   // thing is behind view plane?
+   if (tz < MINZ)
+      return;
+
+   xscale = FixedDiv(projection, tz);
+
+   gxt = -FixedMul(tr_x,viewsin);
+   gyt = FixedMul(tr_y,viewcos);
+   tx = -(gyt+gxt);
+
+   // too far off the side?
+   if (D_abs(tx)>(tz<<2))
+      return;
+
+   // decide which patch to use for sprite relative to player
+#ifdef RANGECHECK
+   if ((unsigned) thing->sprite >= (unsigned)numsprites)
+      I_Error ("R_ProjectSprite: Invalid sprite number %i", thing->sprite);
+#endif
+
+   sprdef = &sprites[thing->sprite];
+
+#ifdef RANGECHECK
+   if ((thing->frame&FF_FRAMEMASK) >= sprdef->numframes)
+      I_Error ("R_ProjectSprite: Invalid sprite frame %i : %i", thing->sprite,
+               thing->frame);
+#endif
+
+   sprframe = &sprdef->spriteframes[thing->frame & FF_FRAMEMASK];
+
+   if (sprframe->rotate)
+   {
+      // choose a different rotation based on player view
+      angle_t ang = R_PointToAngle(thing->x, thing->y);
+      unsigned rot = (ang-thing->angle+(unsigned)(ANG45/2)*9)>>29;
+      lump = sprframe->lump[rot];
+      flip = (boolean) sprframe->flip[rot];
+   }
+   else
+   {
+      // use single rotation for all views
+      lump = sprframe->lump[0];
+      flip = (boolean) sprframe->flip[0];
+   }
+
+   /* calculate edges of the shape
+    * cph 2003/08/1 - fraggle points out that this offset must be flipped if the
+    * sprite is flipped; e.g. FreeDoom imp is messed up by this. */
+   tx -= flip ? spritewidth[lump] - spriteoffset[lump] : spriteoffset[lump];
+   x1 = (centerxfrac + FixedMul(tx,xscale)) >>FRACBITS;
+
+   // off the right side?
+   if (x1 > viewwidth)
+      return;
+
+   tx +=  spritewidth[lump];
+   x2 = ((centerxfrac + FixedMul (tx,xscale) ) >>FRACBITS) - 1;
+
+   // off the left side
+   if (x2 < 0)
+      return;
+
+   gzt = thing->z + spritetopoffset[lump];
+
+   // killough 4/9/98: clip things which are out of view due to height
+   if (thing->z > viewz + FixedDiv(centeryfrac, xscale) ||
+         gzt      < viewz - FixedDiv(centeryfrac-viewheight, xscale))
+      return;
+
+   // killough 3/27/98: exclude things totally separated
+   // from the viewer, by either water or fake ceilings
+   // killough 4/11/98: improve sprite clipping for underwater/fake ceilings
+
+   heightsec = thing->subsector->sector->heightsec;
+
+   if (heightsec != -1)   // only clip things which are in special sectors
+   {
+      int phs = viewplayer->mo->subsector->sector->heightsec;
+      if (phs != -1 && viewz < sectors[phs].floorheight ?
+            thing->z >= sectors[heightsec].floorheight :
+            gzt < sectors[heightsec].floorheight)
+         return;
+      if (phs != -1 && viewz > sectors[phs].ceilingheight ?
+            gzt < sectors[heightsec].ceilingheight &&
+            viewz >= sectors[heightsec].ceilingheight :
+            thing->z >= sectors[heightsec].ceilingheight)
+         return;
+   }
+
+   // store information in a vissprite
+   vis = R_NewVisSprite ();
+
+   // killough 3/27/98: save sector for special clipping later
+   vis->heightsec = heightsec;
+
+   vis->mobjflags = thing->flags;
+   // proff 11/06/98: Changed for high-res
+   vis->scale = xscale;
+   vis->gx = thing->x;
+   vis->gy = thing->y;
+   vis->gz = thing->z;
+   vis->gzt = gzt;                          // killough 3/27/98
+   vis->texturemid = vis->gzt - viewz;
+   vis->x1 = x1 < 0 ? 0 : x1;
+   vis->x2 = x2 >= viewwidth ? viewwidth-1 : x2;
+   iscale = FixedDiv (FRACUNIT, xscale);
+
+   if (flip)
+   {
+      vis->startfrac = spritewidth[lump]-1;
+      vis->xiscale = -iscale;
+   }
+   else
+   {
+      vis->startfrac = 0;
+      vis->xiscale = iscale;
+   }
+
+   if (vis->x1 > x1)
+      vis->startfrac += vis->xiscale*(vis->x1-x1);
+   vis->patch = lump;
+
+   // get light level
+   if (thing->flags & MF_SHADOW)
+      vis->colormap = NULL;             // shadow draw
+   else if (fixedcolormap)
+      vis->colormap = fixedcolormap;      // fixed map
+   else if (thing->frame & FF_FULLBRIGHT)
+      vis->colormap = fullcolormap;     // full bright  // killough 3/20/98
+   else
+   {      // diminished light
+      int index = xscale>>LIGHTSCALESHIFT;
+      if (index >= MAXLIGHTSCALE)
+         index = MAXLIGHTSCALE-1;
+      vis->colormap = spritelights[index];
+   }
+}
+
+//
+// R_AddSprites
+// During BSP traversal, this adds sprites by sector.
+//
+// killough 9/18/98: add lightlevel as parameter, fixing underwater lighting
+void R_AddSprites(subsector_t* subsec, int lightlevel)
+{
+   sector_t* sec=subsec->sector;
+   mobj_t *thing;
+   int    lightnum;
+
+   // BSP is traversed by subsector.
+   // A sector might have been split into several
+   //  subsectors during BSP building.
+   // Thus we check whether its already added.
+
+   if (sec->validcount == validcount)
+      return;
+
+   // Well, now it will be done.
+   sec->validcount = validcount;
+
+   lightnum = (lightlevel >> LIGHTSEGSHIFT)+extralight;
+
+   if (lightnum < 0)
+      spritelights = scalelight[0];
+   else if (lightnum >= LIGHTLEVELS)
+      spritelights = scalelight[LIGHTLEVELS-1];
+   else
+      spritelights = scalelight[lightnum];
+
+   // Handle all things in sector.
+
+   for (thing = sec->thinglist; thing; thing = thing->snext)
+      R_ProjectSprite(thing);
+}
+
+//
+// R_DrawPSprite
+//
+
+void R_DrawPSprite (pspdef_t *psp)
+{
+   fixed_t       tx;
+   int           x1, x2;
+   spritedef_t   *sprdef;
+   spriteframe_t *sprframe;
+   int           lump;
+   boolean       flip;
+   vissprite_t   *vis;
+   vissprite_t   avis;
+
+   // decide which patch to use
+
+#ifdef RANGECHECK
+   if ( (unsigned)psp->state->sprite >= (unsigned)numsprites)
+      I_Error ("R_ProjectSprite: Invalid sprite number %i", psp->state->sprite);
+#endif
+
+   sprdef = &sprites[psp->state->sprite];
+
+#ifdef RANGECHECK
+   if ( (psp->state->frame & FF_FRAMEMASK)  >= sprdef->numframes)
+      I_Error ("R_ProjectSprite: Invalid sprite frame %i : %li",
+               psp->state->sprite, psp->state->frame);
+#endif
+
+   sprframe = &sprdef->spriteframes[psp->state->frame & FF_FRAMEMASK];
+
+   lump = sprframe->lump[0];
+   flip = (boolean) sprframe->flip[0];
+
+   // calculate edges of the shape
+   tx = psp->sx-160*FRACUNIT;
+
+   tx -= spriteoffset[lump];
+   x1 = (centerxfrac + FixedMul (tx,pspritescale))>>FRACBITS;
+
+   // off the right side
+   if (x1 > viewwidth)
+      return;
+
+   tx +=  spritewidth[lump];
+   x2 = ((centerxfrac + FixedMul (tx, pspritescale) ) >>FRACBITS) - 1;
+
+   // off the left side
+   if (x2 < 0)
+      return;
+
+   // store information in a vissprite
+   vis = &avis;
+   vis->mobjflags = 0;
+   // killough 12/98: fix psprite positioning problem
+   vis->texturemid = (BASEYCENTER<<FRACBITS) /* +  FRACUNIT/2 */ -
+                     (psp->sy-spritetopoffset[lump]);
+   vis->x1 = x1 < 0 ? 0 : x1;
+   vis->x2 = x2 >= viewwidth ? viewwidth-1 : x2;
+   // proff 11/06/98: Added for high-res
+   vis->scale = pspritescale;
+
+   if (flip)
+   {
+      vis->xiscale = -pspriteiscale;
+      vis->startfrac = spritewidth[lump]-1;
+   }
+   else
+   {
+      vis->xiscale = pspriteiscale;
+      vis->startfrac = 0;
+   }
+
+   if (vis->x1 > x1)
+      vis->startfrac += vis->xiscale*(vis->x1-x1);
+
+   vis->patch = lump;
+
+   if (viewplayer->powers[pw_invisibility] > 4*32
+         || viewplayer->powers[pw_invisibility] & 8)
+      vis->colormap = NULL;                    // shadow draw
+   else if (fixedcolormap)
+      vis->colormap = fixedcolormap;           // fixed color
+   else if (psp->state->frame & FF_FULLBRIGHT)
+      vis->colormap = fullcolormap;            // full bright // killough 3/20/98
+   else
+      vis->colormap = spritelights[MAXLIGHTSCALE-1];  // local light
+
+   R_DrawVisSprite(vis, vis->x1, vis->x2);
+}
+
+//
+// R_DrawPlayerSprites
+//
+
+void R_DrawPlayerSprites(void)
+{
+   int i, lightnum;
+   pspdef_t *psp;
+
+   // get light level
+   lightnum = (viewplayer->mo->subsector->sector->lightlevel >> LIGHTSEGSHIFT)
+              + extralight;
+
+   if (lightnum < 0)
+      spritelights = scalelight[0];
+   else if (lightnum >= LIGHTLEVELS)
+      spritelights = scalelight[LIGHTLEVELS-1];
+   else
+      spritelights = scalelight[lightnum];
+
+   // clip to screen bounds
+   mfloorclip = screenheightarray;
+   mceilingclip = negonearray;
+
+   // add all active psprites
+   for (i=0, psp=viewplayer->psprites; i<NUMPSPRITES; i++,psp++)
+      if (psp->state)
+         R_DrawPSprite (psp);
+}
+
+//
+// R_SortVisSprites
+//
+// Rewritten by Lee Killough to avoid using unnecessary
+// linked lists, and to use faster sorting algorithm.
+//
+
+#define bcopyp(d, s, n) memcpy(d, s, (n) * sizeof(void *))
+
+// killough 9/2/98: merge sort
+
+static void msort(vissprite_t **s, vissprite_t **t, int n)
+{
+   if (n >= 16)
+   {
+      int n1 = n/2, n2 = n - n1;
+      vissprite_t **s1 = s, **s2 = s + n1, **d = t;
+
+      msort(s1, t, n1);
+      msort(s2, t, n2);
+
+      while ((*s1)->scale > (*s2)->scale ?
+             (*d++ = *s1++, --n1) : (*d++ = *s2++, --n2));
+
+      if (n2)
+         bcopyp(d, s2, n2);
+      else
+         bcopyp(d, s1, n1);
+
+      bcopyp(s, t, n);
+   }
+   else
+   {
+      int i;
+      for (i = 1; i < n; i++)
+      {
+         vissprite_t *temp = s[i];
+         if (s[i-1]->scale < temp->scale)
+         {
+            int j = i;
+            while ((s[j] = s[j-1])->scale < temp->scale && --j);
+            s[j] = temp;
+         }
+      }
+   }
+}
+
+void R_SortVisSprites (void)
+{
+   if (num_vissprite)
+   {
+      int i = num_vissprite;
+
+      // If we need to allocate more pointers for the vissprites,
+      // allocate as many as were allocated for sprites -- killough
+      // killough 9/22/98: allocate twice as many
+
+      if (num_vissprite_ptrs < num_vissprite*2)
+      {
+         free(vissprite_ptrs);  // better than realloc -- no preserving needed
+         vissprite_ptrs = malloc((num_vissprite_ptrs = num_vissprite_alloc*2)
+                                 * sizeof *vissprite_ptrs);
+      }
+
+      while (--i>=0)
+         vissprite_ptrs[i] = vissprites+i;
+
+      // killough 9/22/98: replace qsort with merge sort, since the keys
+      // are roughly in order to begin with, due to BSP rendering.
+
+      msort(vissprite_ptrs, vissprite_ptrs + num_vissprite, num_vissprite);
+   }
+}
+
+//
+// R_DrawSprite
+//
+
+void R_DrawSprite (vissprite_t* spr)
+{
+   drawseg_t *ds;
+   short   clipbot[SCREENWIDTH];       // killough 2/8/98:
+   short   cliptop[SCREENWIDTH];       // change to MAX_*
+   int     x;
+   int     r1;
+   int     r2;
+   fixed_t scale;
+   fixed_t lowscale;
+
+   for (x = spr->x1 ; x<=spr->x2 ; x++)
+      clipbot[x] = cliptop[x] = -2;
+
+   // Scan drawsegs from end to start for obscuring segs.
+   // The first drawseg that has a greater scale is the clip seg.
+
+   // Modified by Lee Killough:
+   // (pointer check was originally nonportable
+   // and buggy, by going past LEFT end of array):
+
+   //    for (ds=ds_p-1 ; ds >= drawsegs ; ds--)    old buggy code
+
+   for (ds=ds_p ; ds-- > drawsegs ; )  // new -- killough
+   {      // determine if the drawseg obscures the sprite
+      if (ds->x1 > spr->x2 || ds->x2 < spr->x1 ||
+            (!ds->silhouette && !ds->maskedtexturecol))
+         continue;      // does not cover sprite
+
+      r1 = ds->x1 < spr->x1 ? spr->x1 : ds->x1;
+      r2 = ds->x2 > spr->x2 ? spr->x2 : ds->x2;
+
+      if (ds->scale1 > ds->scale2)
+      {
+         lowscale = ds->scale2;
+         scale = ds->scale1;
+      }
+      else
+      {
+         lowscale = ds->scale1;
+         scale = ds->scale2;
+      }
+
+      if (scale < spr->scale || (lowscale < spr->scale &&
+                                 !R_PointOnSegSide (spr->gx, spr->gy, ds->curline)))
+      {
+         if (ds->maskedtexturecol)       // masked mid texture?
+            R_RenderMaskedSegRange(ds, r1, r2);
+         continue;               // seg is behind sprite
+      }
+
+      // clip this piece of the sprite
+      // killough 3/27/98: optimized and made much shorter
+
+      if (ds->silhouette&SIL_BOTTOM && spr->gz < ds->bsilheight) //bottom sil
+         for (x=r1 ; x<=r2 ; x++)
+            if (clipbot[x] == -2)
+               clipbot[x] = ds->sprbottomclip[x];
+
+      if (ds->silhouette&SIL_TOP && spr->gzt > ds->tsilheight)   // top sil
+         for (x=r1 ; x<=r2 ; x++)
+            if (cliptop[x] == -2)
+               cliptop[x] = ds->sprtopclip[x];
+   }
+
+   // killough 3/27/98:
+   // Clip the sprite against deep water and/or fake ceilings.
+   // killough 4/9/98: optimize by adding mh
+   // killough 4/11/98: improve sprite clipping for underwater/fake ceilings
+   // killough 11/98: fix disappearing sprites
+
+   if (spr->heightsec != -1)  // only things in specially marked sectors
+   {
+      fixed_t h,mh;
+      int phs = viewplayer->mo->subsector->sector->heightsec;
+      if ((mh = sectors[spr->heightsec].floorheight) > spr->gz &&
+            (h = centeryfrac - FixedMul(mh-=viewz, spr->scale)) >= 0 &&
+            (h >>= FRACBITS) < viewheight) {
+         if (mh <= 0 || (phs != -1 && viewz > sectors[phs].floorheight))
+         {                          // clip bottom
+            for (x=spr->x1 ; x<=spr->x2 ; x++)
+               if (clipbot[x] == -2 || h < clipbot[x])
+                  clipbot[x] = h;
+         }
+         else                        // clip top
+            if (phs != -1 && viewz <= sectors[phs].floorheight) // killough 11/98
+               for (x=spr->x1 ; x<=spr->x2 ; x++)
+                  if (cliptop[x] == -2 || h > cliptop[x])
+                     cliptop[x] = h;
+      }
+
+      if ((mh = sectors[spr->heightsec].ceilingheight) < spr->gzt &&
+            (h = centeryfrac - FixedMul(mh-viewz, spr->scale)) >= 0 &&
+            (h >>= FRACBITS) < viewheight) {
+         if (phs != -1 && viewz >= sectors[phs].ceilingheight)
+         {                         // clip bottom
+            for (x=spr->x1 ; x<=spr->x2 ; x++)
+               if (clipbot[x] == -2 || h < clipbot[x])
+                  clipbot[x] = h;
+         }
+         else                       // clip top
+            for (x=spr->x1 ; x<=spr->x2 ; x++)
+               if (cliptop[x] == -2 || h > cliptop[x])
+                  cliptop[x] = h;
+      }
+   }
+   // killough 3/27/98: end special clipping for deep water / fake ceilings
+
+   // all clipping has been performed, so draw the sprite
+   // check for unclipped columns
+
+   for (x = spr->x1 ; x<=spr->x2 ; x++) {
+      if (clipbot[x] == -2)
+         clipbot[x] = viewheight;
+
+      if (cliptop[x] == -2)
+         cliptop[x] = -1;
+   }
+
+   mfloorclip = clipbot;
+   mceilingclip = cliptop;
+   R_DrawVisSprite (spr, spr->x1, spr->x2);
+}
+
+//
+// R_DrawMasked
+//
+
+void R_DrawMasked(void)
+{
+   int i;
+   drawseg_t *ds;
+
+   R_SortVisSprites();
+
+   // draw all vissprites back to front
+
+//   rendered_vissprites = num_vissprite;
+   for (i = num_vissprite ;--i>=0; )
+      R_DrawSprite(vissprite_ptrs[i]);         // killough
+
+   // render any remaining masked mid textures
+
+   // Modified by Lee Killough:
+   // (pointer check was originally nonportable
+   // and buggy, by going past LEFT end of array):
+
+   //    for (ds=ds_p-1 ; ds >= drawsegs ; ds--)    old buggy code
+
+   for (ds=ds_p ; ds-- > drawsegs ; )  // new -- killough
+      if (ds->maskedtexturecol)
+         R_RenderMaskedSegRange(ds, ds->x1, ds->x2);
+
+   // draw the psprites on top of everything
+   //  but does not draw on side views
+   if (!viewangleoffset)
+      R_DrawPlayerSprites ();
+}