/*
Copyright (C) 1997-2001 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.

*/
  
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <math.h>
#include <stdarg.h>

#include "../client/ref.h"

#define REF_VERSION     "SOFT 0.01"

// up / down
#define PITCH   0

// left / right
#define YAW             1

// fall over
#define ROLL    2


/*

  skins will be outline flood filled and mip mapped
  pics and sprites with alpha will be outline flood filled
  pic won't be mip mapped

  model skin
  sprite frame
  wall texture
  pic

*/

typedef enum 
{
	it_skin,
	it_sprite,
	it_wall,
	it_pic,
	it_sky
} imagetype_t;

typedef struct image_s
{
	char    name[MAX_QPATH];        // game path, including extension
	imagetype_t     type;
	int             width, height;
	qboolean        transparent;    // true if any 255 pixels in image
	int             registration_sequence;  // 0 = free
	byte		*pixels[4];				// mip levels
} image_t;


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

typedef unsigned char pixel_t;

typedef struct vrect_s
{
	int                             x,y,width,height;
	struct vrect_s  *pnext;
} vrect_t;

typedef struct
{
	pixel_t                 *buffer;                // invisible buffer
	pixel_t                 *colormap;              // 256 * VID_GRADES size
	pixel_t                 *alphamap;              // 256 * 256 translucency map
	int                             rowbytes;               // may be > width if displayed in a window
									// can be negative for stupid dibs
	int						width;          
	int						height;
} viddef_t;

typedef enum
{
	rserr_ok,

	rserr_invalid_fullscreen,
	rserr_invalid_mode,

	rserr_unknown
} rserr_t;

extern viddef_t vid;

// !!! if this is changed, it must be changed in asm_draw.h too !!!
typedef struct
{
	vrect_t         vrect;                          // subwindow in video for refresh
									// FIXME: not need vrect next field here?
	vrect_t         aliasvrect;                     // scaled Alias version
	int                     vrectright, vrectbottom;        // right & bottom screen coords
	int                     aliasvrectright, aliasvrectbottom;      // scaled Alias versions
	float           vrectrightedge;                 // rightmost right edge we care about,
										//  for use in edge list
	float           fvrectx, fvrecty;               // for floating-point compares
	float           fvrectx_adj, fvrecty_adj; // left and top edges, for clamping
	int                     vrect_x_adj_shift20;    // (vrect.x + 0.5 - epsilon) << 20
	int                     vrectright_adj_shift20; // (vrectright + 0.5 - epsilon) << 20
	float           fvrectright_adj, fvrectbottom_adj;
										// right and bottom edges, for clamping
	float           fvrectright;                    // rightmost edge, for Alias clamping
	float           fvrectbottom;                   // bottommost edge, for Alias clamping
	float           horizontalFieldOfView;  // at Z = 1.0, this many X is visible 
										// 2.0 = 90 degrees
	float           xOrigin;                        // should probably always be 0.5
	float           yOrigin;                        // between be around 0.3 to 0.5

	vec3_t          vieworg;
	vec3_t          viewangles;
	
	int                     ambientlight;
} oldrefdef_t;

extern oldrefdef_t      r_refdef;

#include "r_model.h"

#define CACHE_SIZE      32

/*
====================================================

  CONSTANTS

====================================================
*/

#define VID_CBITS       6
#define VID_GRADES      (1 << VID_CBITS)


// r_shared.h: general refresh-related stuff shared between the refresh and the
// driver


#define MAXVERTS        64              // 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       1200
#define MAXWIDTH        1600

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


// d_iface.h: interface header file for rasterization driver modules

#define WARP_WIDTH              320
#define WARP_HEIGHT             240

#define MAX_LBM_HEIGHT  480


#define PARTICLE_Z_CLIP 8.0

// !!! must be kept the same as in quakeasm.h !!!
#define TRANSPARENT_COLOR       0xFF


// !!! if this is changed, it must be changed in d_ifacea.h too !!!
#define TURB_TEX_SIZE   64              // base turbulent texture size

// !!! if this is changed, it must be changed in d_ifacea.h too !!!
#define CYCLE                   128             // turbulent cycle size

#define SCANBUFFERPAD           0x1000

#define DS_SPAN_LIST_END        -128

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

// 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
#define ALIAS_XY_CLIP_MASK                      0x000F

#define SURFCACHE_SIZE_AT_320X240    1024*768

#define BMODEL_FULLY_CLIPPED    0x10 // value returned by R_BmodelCheckBBox ()
									 //  if bbox is trivially rejected

#define XCENTERING      (1.0 / 2.0)
#define YCENTERING      (1.0 / 2.0)

#define CLIP_EPSILON            0.001

#define BACKFACE_EPSILON        0.01

// !!! if this is changed, it must be changed in asm_draw.h too !!!
#define NEAR_CLIP       0.01


#define MAXALIASVERTS           2000    // TODO: tune this
#define ALIAS_Z_CLIP_PLANE      4

// turbulence stuff

#define AMP             8*0x10000
#define AMP2    3
#define SPEED   20


/*
====================================================

TYPES

====================================================
*/

typedef struct
{
	float   u, v;
	float   s, t;
	float   zi;
} emitpoint_t;

/*
** if you change this structure be sure to change the #defines
** listed after it!
*/
#define SMALL_FINALVERT 0

#if SMALL_FINALVERT

typedef struct finalvert_s {
	short           u, v, s, t;
	int             l;
	int             zi;
	int             flags;
	float   xyz[3];         // eye space
} finalvert_t;

#define FINALVERT_V0     0
#define FINALVERT_V1     2
#define FINALVERT_V2     4
#define FINALVERT_V3     6
#define FINALVERT_V4     8
#define FINALVERT_V5    12
#define FINALVERT_FLAGS 16
#define FINALVERT_X     20
#define FINALVERT_Y     24
#define FINALVERT_Z     28
#define FINALVERT_SIZE  32

#else

typedef struct finalvert_s {
	int             u, v, s, t;
	int             l;
	int             zi;
	int             flags;
	float   xyz[3];         // eye space
} finalvert_t;

#define FINALVERT_V0     0
#define FINALVERT_V1     4
#define FINALVERT_V2     8
#define FINALVERT_V3    12
#define FINALVERT_V4    16
#define FINALVERT_V5    20
#define FINALVERT_FLAGS 24
#define FINALVERT_X     28
#define FINALVERT_Y     32
#define FINALVERT_Z     36
#define FINALVERT_SIZE  40

#endif

typedef struct
{
	void                            *pskin;
	int                                     pskindesc;
	int                                     skinwidth;
	int                                     skinheight;
	dtriangle_t                     *ptriangles;
	finalvert_t                     *pfinalverts;
	int                                     numtriangles;
	int                                     drawtype;
	int                                     seamfixupX16;
	qboolean                        do_vis_thresh;
	int                                     vis_thresh;
} affinetridesc_t;

typedef struct
{
	byte            *surfdat;       // destination for generated surface
	int                     rowbytes;       // destination logical width in bytes
	msurface_t      *surf;          // description for surface to generate
	fixed8_t        lightadj[MAXLIGHTMAPS];
							// adjust for lightmap levels for dynamic lighting
	image_t			*image;
	int                     surfmip;        // mipmapped ratio of surface texels / world pixels
	int                     surfwidth;      // in mipmapped texels
	int                     surfheight;     // in mipmapped texels
} drawsurf_t;



typedef struct {
	int                     ambientlight;
	int                     shadelight;
	float           *plightvec;
} alight_t;

// clipped bmodel edges

typedef struct bedge_s
{
	mvertex_t               *v[2];
	struct bedge_s  *pnext;
} bedge_t;


// !!! if this is changed, it must be changed in asm_draw.h too !!!
typedef struct clipplane_s
{
	vec3_t          normal;
	float           dist;
	struct          clipplane_s     *next;
	byte            leftedge;
	byte            rightedge;
	byte            reserved[2];
} clipplane_t;


typedef struct surfcache_s
{
	struct surfcache_s      *next;
	struct surfcache_s      **owner;                // NULL is an empty chunk of memory
	int                                     lightadj[MAXLIGHTMAPS]; // checked for strobe flush
	int                                     dlight;
	int                                     size;           // including header
	unsigned                        width;
	unsigned                        height;         // DEBUG only needed for debug
	float                           mipscale;
	image_t							*image;
	byte                            data[4];        // width*height elements
} surfcache_t;

// !!! 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;

// used by the polygon drawer (R_POLY.C) and sprite setup code (R_SPRITE.C)
typedef struct
{
	int                     nump;
	emitpoint_t     *pverts;
	byte            *pixels;                        // image
	int                     pixel_width;            // image width
	int         pixel_height;       // image height
	vec3_t          vup, vright, vpn;       // in worldspace, for plane eq
	float       dist;
	float       s_offset, t_offset;
	float       viewer_position[3];
	void       (*drawspanlet)( void );
	int         stipple_parity;
} polydesc_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
	msurface_t      *msurf;
	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;

// !!! 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;