/*
Copyright (C) 1996-1997 Id Software, Inc.

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.

*/
#ifndef GLQUAKE
// r_shared.h: general refresh-related stuff shared between the refresh and the
// driver

// FIXME: clean up and move into d_iface.h

#ifndef _R_SHARED_H_
#define _R_SHARED_H_

#define MAXVERTS  16          // max points in a surface polygon
#define MAXWORKINGVERTS (MAXVERTS+4)  // max points in an intermediate
                    //  polygon (while processing)
// !!! if this is changed, it must be changed in d_ifacea.h too !!!
#define MAXHEIGHT 1024
#define MAXWIDTH  1280

#define INFINITE_DISTANCE 0x10000   // distance that's always guaranteed to
                    //  be farther away than anything in
                    //  the scene

//===================================================================

extern void R_DrawLine (polyvert_t *polyvert0, polyvert_t *polyvert1);

extern int    cachewidth;
extern pixel_t  *cacheblock;
extern int    screenwidth;

extern  float pixelAspect;

extern int    r_drawnpolycount;

extern cvar_t r_clearcolor;

extern int  sintable[1280];
extern int  intsintable[1280];

extern  vec3_t  vup, base_vup;
extern  vec3_t  vpn, base_vpn;
extern  vec3_t  vright, base_vright;
extern  entity_t    *currententity;

#define NUMSTACKEDGES   2000
#define MINEDGES      NUMSTACKEDGES
#define NUMSTACKSURFACES  1000
#define MINSURFACES     NUMSTACKSURFACES
#define MAXSPANS      3000

// !!! if this is changed, it must be changed in asm_draw.h too !!!
typedef struct espan_s
{
  int       u, v, count;
  struct espan_s  *pnext;
} espan_t;

// FIXME: compress, make a union if that will help
// insubmodel is only 1, flags is fewer than 32, spanstate could be a byte
typedef struct surf_s
{
  struct surf_s *next;      // active surface stack in r_edge.c
  struct surf_s *prev;      // used in r_edge.c for active surf stack
  struct espan_s  *spans;     // pointer to linked list of spans to draw
  int     key;        // sorting key (BSP order)
  int     last_u;       // set during tracing
  int     spanstate;      // 0 = not in span
                  // 1 = in span
                  // -1 = in inverted span (end before
                  //  start)
  int     flags;        // currentface flags
  void    *data;        // associated data like msurface_t
  entity_t  *entity;
  float   nearzi;       // nearest 1/z on surface, for mipmapping
  qboolean  insubmodel;
  float   d_ziorigin, d_zistepu, d_zistepv;

  int     pad[2];       // to 64 bytes
} surf_t;

extern  surf_t  *surfaces, *surface_p, *surf_max;

// surfaces are generated in back to front order by the bsp, so if a surf
// pointer is greater than another one, it should be drawn in front
// surfaces[1] is the background, and is used as the active surface stack.
// surfaces[0] is a dummy, because index 0 is used to indicate no surface
//  attached to an edge_t

//===================================================================

extern vec3_t sxformaxis[4];  // s axis transformed into viewspace
extern vec3_t txformaxis[4];  // t axis transformed into viewspac

extern vec3_t modelorg, base_modelorg;

extern  float xcenter, ycenter;
extern  float xscale, yscale;
extern  float xscaleinv, yscaleinv;
extern  float xscaleshrink, yscaleshrink;

extern  int d_lightstylevalue[256]; // 8.8 frac of base light value

extern void TransformVector (vec3_t in, vec3_t out);
extern void SetUpForLineScan(fixed8_t startvertu, fixed8_t startvertv,
  fixed8_t endvertu, fixed8_t endvertv);

extern int  r_skymade;
extern void R_MakeSky (void);

extern int  ubasestep, errorterm, erroradjustup, erroradjustdown;

// flags in finalvert_t.flags
#define ALIAS_LEFT_CLIP       0x0001
#define ALIAS_TOP_CLIP        0x0002
#define ALIAS_RIGHT_CLIP      0x0004
#define ALIAS_BOTTOM_CLIP     0x0008
#define ALIAS_Z_CLIP        0x0010
// !!! if this is changed, it must be changed in d_ifacea.h too !!!
#define ALIAS_ONSEAM        0x0020  // also defined in modelgen.h;
                      //  must be kept in sync
#define ALIAS_XY_CLIP_MASK      0x000F

// !!! if this is changed, it must be changed in asm_draw.h too !!!
typedef struct edge_s
{
  fixed16_t   u;
  fixed16_t   u_step;
  struct edge_s *prev, *next;
  unsigned short  surfs[2];
  struct edge_s *nextremove;
  float     nearzi;
  medge_t     *owner;
} edge_t;

#endif  // _R_SHARED_H_

#endif  // GLQUAKE