//
// Copyright(C) 1993-1996 Id Software, Inc.
// Copyright(C) 2005-2014 Simon Howard
//
// 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.
//
//
// DESCRIPTION:  the automap code
//


#include <stdio.h>

#include "deh_main.h"

#include "z_zone.h"
#include "doomkeys.h"
#include "doomdef.h"
#include "st_stuff.h"
#include "p_local.h"
#include "w_wad.h"

#include "m_cheat.h"
#include "m_controls.h"
#include "m_misc.h"
#include "i_system.h"
#include "i_timer.h"
#include "i_video.h"

// Needs access to LFB.
#include "v_video.h"

// State.
#include "doomstat.h"
#include "r_state.h"

// Data.
#include "dstrings.h"

#include "am_map.h"


// For use if I do walls with outsides/insides
#define REDS		(256-5*16)
#define REDRANGE	16
#define BLUES		(256-4*16+8)
#define BLUERANGE	8
#define GREENS		(7*16)
#define GREENRANGE	16
#define GRAYS		(6*16)
#define GRAYSRANGE	16
#define BROWNS		(4*16)
#define BROWNRANGE	16
#define YELLOWS		(256-32+7)
#define YELLOWRANGE	1
#define BLACK		0
#define WHITE		(256-47)

// Automap colors
#define BACKGROUND	BLACK
#define YOURCOLORS	WHITE
#define YOURRANGE	0
#define WALLCOLORS	REDS
#define WALLRANGE	REDRANGE
#define TSWALLCOLORS	GRAYS
#define TSWALLRANGE	GRAYSRANGE
#define FDWALLCOLORS	BROWNS
#define FDWALLRANGE	BROWNRANGE
#define CDWALLCOLORS	YELLOWS
#define CDWALLRANGE	YELLOWRANGE
#define THINGCOLORS	GREENS
#define THINGRANGE	GREENRANGE
#define SECRETWALLCOLORS WALLCOLORS
#define SECRETWALLRANGE WALLRANGE
#define GRIDCOLORS	(GRAYS + GRAYSRANGE/2)
#define GRIDRANGE	0
#define XHAIRCOLORS	GRAYS

// drawing stuff

#define AM_NUMMARKPOINTS 10

// scale on entry
#define INITSCALEMTOF (.2*FRACUNIT)
// how much the automap moves window per tic in frame-buffer coordinates
// moves 140 pixels in 1 second
#define F_PANINC	4
// how much zoom-in per tic
// goes to 2x in 1 second
#define M_ZOOMIN        ((int) (1.02*FRACUNIT))
// how much zoom-out per tic
// pulls out to 0.5x in 1 second
#define M_ZOOMOUT       ((int) (FRACUNIT/1.02))

// translates between frame-buffer and map distances
#define FTOM(x) FixedMul(((x)<<FRACBITS),scale_ftom)
#define MTOF(x) (FixedMul((x),scale_mtof)>>FRACBITS)
// translates between frame-buffer and map coordinates
#define CXMTOF(x)  (f_x + MTOF((x)-m_x))
#define CYMTOF(y)  (f_y + (f_h - MTOF((y)-m_y)))

// the following is crap
#define LINE_NEVERSEE ML_DONTDRAW

typedef struct
{
    int x, y;
} fpoint_t;

typedef struct
{
    fpoint_t a, b;
} fline_t;

typedef struct
{
    fixed_t		x,y;
} mpoint_t;

typedef struct
{
    mpoint_t a, b;
} mline_t;

typedef struct
{
    fixed_t slp, islp;
} islope_t;



//
// The vector graphics for the automap.
//  A line drawing of the player pointing right,
//   starting from the middle.
//
#define R ((8*PLAYERRADIUS)/7)
mline_t player_arrow[] = {
    { { -R+R/8, 0 }, { R, 0 } }, // -----
    { { R, 0 }, { R-R/2, R/4 } },  // ----->
    { { R, 0 }, { R-R/2, -R/4 } },
    { { -R+R/8, 0 }, { -R-R/8, R/4 } }, // >---->
    { { -R+R/8, 0 }, { -R-R/8, -R/4 } },
    { { -R+3*R/8, 0 }, { -R+R/8, R/4 } }, // >>--->
    { { -R+3*R/8, 0 }, { -R+R/8, -R/4 } }
};
#undef R

#define R ((8*PLAYERRADIUS)/7)
mline_t cheat_player_arrow[] = {
    { { -R+R/8, 0 }, { R, 0 } }, // -----
    { { R, 0 }, { R-R/2, R/6 } },  // ----->
    { { R, 0 }, { R-R/2, -R/6 } },
    { { -R+R/8, 0 }, { -R-R/8, R/6 } }, // >----->
    { { -R+R/8, 0 }, { -R-R/8, -R/6 } },
    { { -R+3*R/8, 0 }, { -R+R/8, R/6 } }, // >>----->
    { { -R+3*R/8, 0 }, { -R+R/8, -R/6 } },
    { { -R/2, 0 }, { -R/2, -R/6 } }, // >>-d--->
    { { -R/2, -R/6 }, { -R/2+R/6, -R/6 } },
    { { -R/2+R/6, -R/6 }, { -R/2+R/6, R/4 } },
    { { -R/6, 0 }, { -R/6, -R/6 } }, // >>-dd-->
    { { -R/6, -R/6 }, { 0, -R/6 } },
    { { 0, -R/6 }, { 0, R/4 } },
    { { R/6, R/4 }, { R/6, -R/7 } }, // >>-ddt->
    { { R/6, -R/7 }, { R/6+R/32, -R/7-R/32 } },
    { { R/6+R/32, -R/7-R/32 }, { R/6+R/10, -R/7 } }
};
#undef R

#define R (FRACUNIT)
mline_t triangle_guy[] = {
    { { (fixed_t)(-.867*R), (fixed_t)(-.5*R) }, { (fixed_t)(.867*R ), (fixed_t)(-.5*R) } },
    { { (fixed_t)(.867*R ), (fixed_t)(-.5*R) }, { (fixed_t)(0      ), (fixed_t)(R    ) } },
    { { (fixed_t)(0      ), (fixed_t)(R    ) }, { (fixed_t)(-.867*R), (fixed_t)(-.5*R) } }
};
#undef R

#define R (FRACUNIT)
mline_t thintriangle_guy[] = {
    { { (fixed_t)(-.5*R), (fixed_t)(-.7*R) }, { (fixed_t)(R    ), (fixed_t)(0    ) } },
    { { (fixed_t)(R    ), (fixed_t)(0    ) }, { (fixed_t)(-.5*R), (fixed_t)(.7*R ) } },
    { { (fixed_t)(-.5*R), (fixed_t)(.7*R ) }, { (fixed_t)(-.5*R), (fixed_t)(-.7*R) } }
};
#undef R




static int 	cheating = 0;
static int 	grid = 0;

boolean    	automapactive = false;
static int 	finit_width = SCREENWIDTH;
static int 	finit_height = SCREENHEIGHT - ST_HEIGHT;

// location of window on screen
static int 	f_x;
static int	f_y;

// size of window on screen
static int 	f_w;
static int	f_h;

static int 	lightlev; 		// used for funky strobing effect
static pixel_t*	fb; 			// pseudo-frame buffer
static int 	amclock;

static mpoint_t m_paninc; // how far the window pans each tic (map coords)
static fixed_t 	mtof_zoommul; // how far the window zooms in each tic (map coords)
static fixed_t 	ftom_zoommul; // how far the window zooms in each tic (fb coords)

static fixed_t 	m_x, m_y;   // LL x,y where the window is on the map (map coords)
static fixed_t 	m_x2, m_y2; // UR x,y where the window is on the map (map coords)

//
// width/height of window on map (map coords)
//
static fixed_t 	m_w;
static fixed_t	m_h;

// based on level size
static fixed_t 	min_x;
static fixed_t	min_y; 
static fixed_t 	max_x;
static fixed_t  max_y;

static fixed_t 	max_w; // max_x-min_x,
static fixed_t  max_h; // max_y-min_y

// based on player size
static fixed_t 	min_w;
static fixed_t  min_h;


static fixed_t 	min_scale_mtof; // used to tell when to stop zooming out
static fixed_t 	max_scale_mtof; // used to tell when to stop zooming in

// old stuff for recovery later
static fixed_t old_m_w, old_m_h;
static fixed_t old_m_x, old_m_y;

// old location used by the Follower routine
static mpoint_t f_oldloc;

// used by MTOF to scale from map-to-frame-buffer coords
static fixed_t scale_mtof = (fixed_t)INITSCALEMTOF;
// used by FTOM to scale from frame-buffer-to-map coords (=1/scale_mtof)
static fixed_t scale_ftom;

static player_t *plr; // the player represented by an arrow

static patch_t *marknums[10]; // numbers used for marking by the automap
static mpoint_t markpoints[AM_NUMMARKPOINTS]; // where the points are
static int markpointnum = 0; // next point to be assigned

static int followplayer = 1; // specifies whether to follow the player around

cheatseq_t cheat_amap = CHEAT("iddt", 0);

static boolean stopped = true;

// Calculates the slope and slope according to the x-axis of a line
// segment in map coordinates (with the upright y-axis n' all) so
// that it can be used with the brain-dead drawing stuff.

void
AM_getIslope
( mline_t*	ml,
  islope_t*	is )
{
    int dx, dy;

    dy = ml->a.y - ml->b.y;
    dx = ml->b.x - ml->a.x;
    if (!dy) is->islp = (dx<0?-INT_MAX:INT_MAX);
    else is->islp = FixedDiv(dx, dy);
    if (!dx) is->slp = (dy<0?-INT_MAX:INT_MAX);
    else is->slp = FixedDiv(dy, dx);

}

//
//
//
void AM_activateNewScale(void)
{
    m_x += m_w/2;
    m_y += m_h/2;
    m_w = FTOM(f_w);
    m_h = FTOM(f_h);
    m_x -= m_w/2;
    m_y -= m_h/2;
    m_x2 = m_x + m_w;
    m_y2 = m_y + m_h;
}

//
//
//
void AM_saveScaleAndLoc(void)
{
    old_m_x = m_x;
    old_m_y = m_y;
    old_m_w = m_w;
    old_m_h = m_h;
}

//
//
//
void AM_restoreScaleAndLoc(void)
{

    m_w = old_m_w;
    m_h = old_m_h;
    if (!followplayer)
    {
	m_x = old_m_x;
	m_y = old_m_y;
    } else {
	m_x = plr->mo->x - m_w/2;
	m_y = plr->mo->y - m_h/2;
    }
    m_x2 = m_x + m_w;
    m_y2 = m_y + m_h;

    // Change the scaling multipliers
    scale_mtof = FixedDiv(f_w<<FRACBITS, m_w);
    scale_ftom = FixedDiv(FRACUNIT, scale_mtof);
}

//
// adds a marker at the current location
//
void AM_addMark(void)
{
    markpoints[markpointnum].x = m_x + m_w/2;
    markpoints[markpointnum].y = m_y + m_h/2;
    markpointnum = (markpointnum + 1) % AM_NUMMARKPOINTS;

}

//
// Determines bounding box of all vertices,
// sets global variables controlling zoom range.
//
void AM_findMinMaxBoundaries(void)
{
    int i;
    fixed_t a;
    fixed_t b;

    min_x = min_y =  INT_MAX;
    max_x = max_y = -INT_MAX;
  
    for (i=0;i<numvertexes;i++)
    {
	if (vertexes[i].x < min_x)
	    min_x = vertexes[i].x;
	else if (vertexes[i].x > max_x)
	    max_x = vertexes[i].x;
    
	if (vertexes[i].y < min_y)
	    min_y = vertexes[i].y;
	else if (vertexes[i].y > max_y)
	    max_y = vertexes[i].y;
    }
  
    max_w = max_x - min_x;
    max_h = max_y - min_y;

    min_w = 2*PLAYERRADIUS; // const? never changed?
    min_h = 2*PLAYERRADIUS;

    a = FixedDiv(f_w<<FRACBITS, max_w);
    b = FixedDiv(f_h<<FRACBITS, max_h);
  
    min_scale_mtof = a < b ? a : b;
    max_scale_mtof = FixedDiv(f_h<<FRACBITS, 2*PLAYERRADIUS);

}


//
//
//
void AM_changeWindowLoc(void)
{
    if (m_paninc.x || m_paninc.y)
    {
	followplayer = 0;
	f_oldloc.x = INT_MAX;
    }

    m_x += m_paninc.x;
    m_y += m_paninc.y;

    if (m_x + m_w/2 > max_x)
	m_x = max_x - m_w/2;
    else if (m_x + m_w/2 < min_x)
	m_x = min_x - m_w/2;
  
    if (m_y + m_h/2 > max_y)
	m_y = max_y - m_h/2;
    else if (m_y + m_h/2 < min_y)
	m_y = min_y - m_h/2;

    m_x2 = m_x + m_w;
    m_y2 = m_y + m_h;
}


//
//
//
void AM_initVariables(void)
{
    int pnum;
    static event_t st_notify = { ev_keyup, AM_MSGENTERED, 0, 0 };

    automapactive = true;
    fb = I_VideoBuffer;

    f_oldloc.x = INT_MAX;
    amclock = 0;
    lightlev = 0;

    m_paninc.x = m_paninc.y = 0;
    ftom_zoommul = FRACUNIT;
    mtof_zoommul = FRACUNIT;

    m_w = FTOM(f_w);
    m_h = FTOM(f_h);

    // find player to center on initially
    if (playeringame[consoleplayer])
    {
        plr = &players[consoleplayer];
    }
    else
    {
        plr = &players[0];

	for (pnum=0;pnum<MAXPLAYERS;pnum++)
        {
	    if (playeringame[pnum])
            {
                plr = &players[pnum];
		break;
            }
        }
    }

    m_x = plr->mo->x - m_w/2;
    m_y = plr->mo->y - m_h/2;
    AM_changeWindowLoc();

    // for saving & restoring
    old_m_x = m_x;
    old_m_y = m_y;
    old_m_w = m_w;
    old_m_h = m_h;

    // inform the status bar of the change
    ST_Responder(&st_notify);

}

//
// 
//
void AM_loadPics(void)
{
    int i;
    char namebuf[9];
  
    for (i=0;i<10;i++)
    {
	DEH_snprintf(namebuf, 9, "AMMNUM%d", i);
	marknums[i] = W_CacheLumpName(namebuf, PU_STATIC);
    }

}

void AM_unloadPics(void)
{
    int i;
    char namebuf[9];
  
    for (i=0;i<10;i++)
    {
	DEH_snprintf(namebuf, 9, "AMMNUM%d", i);
	W_ReleaseLumpName(namebuf);
    }
}

void AM_clearMarks(void)
{
    int i;

    for (i=0;i<AM_NUMMARKPOINTS;i++)
	markpoints[i].x = -1; // means empty
    markpointnum = 0;
}

//
// should be called at the start of every level
// right now, i figure it out myself
//
void AM_LevelInit(void)
{
    f_x = f_y = 0;
    f_w = finit_width;
    f_h = finit_height;

    AM_clearMarks();

    AM_findMinMaxBoundaries();
    scale_mtof = FixedDiv(min_scale_mtof, (int) (0.7*FRACUNIT));
    if (scale_mtof > max_scale_mtof)
	scale_mtof = min_scale_mtof;
    scale_ftom = FixedDiv(FRACUNIT, scale_mtof);
}




//
//
//
void AM_Stop (void)
{
    static event_t st_notify = { 0, ev_keyup, AM_MSGEXITED, 0 };

    AM_unloadPics();
    automapactive = false;
    ST_Responder(&st_notify);
    stopped = true;
}

//
//
//
void AM_Start (void)
{
    static int lastlevel = -1, lastepisode = -1;

    if (!stopped) AM_Stop();
    stopped = false;
    if (lastlevel != gamemap || lastepisode != gameepisode)
    {
	AM_LevelInit();
	lastlevel = gamemap;
	lastepisode = gameepisode;
    }
    AM_initVariables();
    AM_loadPics();
}

//
// set the window scale to the maximum size
//
void AM_minOutWindowScale(void)
{
    scale_mtof = min_scale_mtof;
    scale_ftom = FixedDiv(FRACUNIT, scale_mtof);
    AM_activateNewScale();
}

//
// set the window scale to the minimum size
//
void AM_maxOutWindowScale(void)
{
    scale_mtof = max_scale_mtof;
    scale_ftom = FixedDiv(FRACUNIT, scale_mtof);
    AM_activateNewScale();
}


//
// Handle events (user inputs) in automap mode
//
boolean
AM_Responder
( event_t*	ev )
{

    int rc;
    static int bigstate=0;
    static char buffer[20];
    int key;

    rc = false;

    if (ev->type == ev_joystick && joybautomap >= 0
        && (ev->data1 & (1 << joybautomap)) != 0)
    {
        joywait = I_GetTime() + 5;

        if (!automapactive)
        {
            AM_Start ();
            viewactive = false;
        }
        else
        {
            bigstate = 0;
            viewactive = true;
            AM_Stop ();
        }

        return true;
    }

    if (!automapactive)
    {
	if (ev->type == ev_keydown && ev->data1 == key_map_toggle)
	{
	    AM_Start ();
	    viewactive = false;
	    rc = true;
	}
    }
    else if (ev->type == ev_keydown)
    {
	rc = true;
        key = ev->data1;

        if (key == key_map_east)          // pan right
        {
            if (!followplayer) m_paninc.x = FTOM(F_PANINC);
            else rc = false;
        }
        else if (key == key_map_west)     // pan left
        {
            if (!followplayer) m_paninc.x = -FTOM(F_PANINC);
            else rc = false;
        }
        else if (key == key_map_north)    // pan up
        {
            if (!followplayer) m_paninc.y = FTOM(F_PANINC);
            else rc = false;
        }
        else if (key == key_map_south)    // pan down
        {
            if (!followplayer) m_paninc.y = -FTOM(F_PANINC);
            else rc = false;
        }
        else if (key == key_map_zoomout)  // zoom out
        {
            mtof_zoommul = M_ZOOMOUT;
            ftom_zoommul = M_ZOOMIN;
        }
        else if (key == key_map_zoomin)   // zoom in
        {
            mtof_zoommul = M_ZOOMIN;
            ftom_zoommul = M_ZOOMOUT;
        }
        else if (key == key_map_toggle)
        {
            bigstate = 0;
            viewactive = true;
            AM_Stop ();
        }
        else if (key == key_map_maxzoom)
        {
            bigstate = !bigstate;
            if (bigstate)
            {
                AM_saveScaleAndLoc();
                AM_minOutWindowScale();
            }
            else AM_restoreScaleAndLoc();
        }
        else if (key == key_map_follow)
        {
            followplayer = !followplayer;
            f_oldloc.x = INT_MAX;
            if (followplayer)
                plr->message = DEH_String(AMSTR_FOLLOWON);
            else
                plr->message = DEH_String(AMSTR_FOLLOWOFF);
        }
        else if (key == key_map_grid)
        {
            grid = !grid;
            if (grid)
                plr->message = DEH_String(AMSTR_GRIDON);
            else
                plr->message = DEH_String(AMSTR_GRIDOFF);
        }
        else if (key == key_map_mark)
        {
            M_snprintf(buffer, sizeof(buffer), "%s %d",
                       DEH_String(AMSTR_MARKEDSPOT), markpointnum);
            plr->message = buffer;
            AM_addMark();
        }
        else if (key == key_map_clearmark)
        {
            AM_clearMarks();
            plr->message = DEH_String(AMSTR_MARKSCLEARED);
        }
        else
        {
            rc = false;
        }

        if ((!deathmatch || gameversion <= exe_doom_1_8)
         && cht_CheckCheat(&cheat_amap, ev->data2))
        {
            rc = false;
            cheating = (cheating + 1) % 3;
        }
    }
    else if (ev->type == ev_keyup)
    {
        rc = false;
        key = ev->data1;

        if (key == key_map_east)
        {
            if (!followplayer) m_paninc.x = 0;
        }
        else if (key == key_map_west)
        {
            if (!followplayer) m_paninc.x = 0;
        }
        else if (key == key_map_north)
        {
            if (!followplayer) m_paninc.y = 0;
        }
        else if (key == key_map_south)
        {
            if (!followplayer) m_paninc.y = 0;
        }
        else if (key == key_map_zoomout || key == key_map_zoomin)
        {
            mtof_zoommul = FRACUNIT;
            ftom_zoommul = FRACUNIT;
        }
    }

    return rc;

}


//
// Zooming
//
void AM_changeWindowScale(void)
{

    // Change the scaling multipliers
    scale_mtof = FixedMul(scale_mtof, mtof_zoommul);
    scale_ftom = FixedDiv(FRACUNIT, scale_mtof);

    if (scale_mtof < min_scale_mtof)
	AM_minOutWindowScale();
    else if (scale_mtof > max_scale_mtof)
	AM_maxOutWindowScale();
    else
	AM_activateNewScale();
}


//
//
//
void AM_doFollowPlayer(void)
{

    if (f_oldloc.x != plr->mo->x || f_oldloc.y != plr->mo->y)
    {
	m_x = FTOM(MTOF(plr->mo->x)) - m_w/2;
	m_y = FTOM(MTOF(plr->mo->y)) - m_h/2;
	m_x2 = m_x + m_w;
	m_y2 = m_y + m_h;
	f_oldloc.x = plr->mo->x;
	f_oldloc.y = plr->mo->y;

	//  m_x = FTOM(MTOF(plr->mo->x - m_w/2));
	//  m_y = FTOM(MTOF(plr->mo->y - m_h/2));
	//  m_x = plr->mo->x - m_w/2;
	//  m_y = plr->mo->y - m_h/2;

    }

}

//
//
//
void AM_updateLightLev(void)
{
    static int nexttic = 0;
    //static int litelevels[] = { 0, 3, 5, 6, 6, 7, 7, 7 };
    static int litelevels[] = { 0, 4, 7, 10, 12, 14, 15, 15 };
    static int litelevelscnt = 0;
   
    // Change light level
    if (amclock>nexttic)
    {
	lightlev = litelevels[litelevelscnt++];
	if (litelevelscnt == arrlen(litelevels)) litelevelscnt = 0;
	nexttic = amclock + 6 - (amclock % 6);
    }

}


//
// Updates on Game Tick
//
void AM_Ticker (void)
{

    if (!automapactive)
	return;

    amclock++;

    if (followplayer)
	AM_doFollowPlayer();

    // Change the zoom if necessary
    if (ftom_zoommul != FRACUNIT)
	AM_changeWindowScale();

    // Change x,y location
    if (m_paninc.x || m_paninc.y)
	AM_changeWindowLoc();

    // Update light level
    // AM_updateLightLev();

}


//
// Clear automap frame buffer.
//
void AM_clearFB(int color)
{
    memset(fb, color, f_w*f_h*sizeof(*fb));
}


//
// Automap clipping of lines.
//
// Based on Cohen-Sutherland clipping algorithm but with a slightly
// faster reject and precalculated slopes.  If the speed is needed,
// use a hash algorithm to handle  the common cases.
//
boolean
AM_clipMline
( mline_t*	ml,
  fline_t*	fl )
{
    enum
    {
	LEFT	=1,
	RIGHT	=2,
	BOTTOM	=4,
	TOP	=8
    };
    
    register int	outcode1 = 0;
    register int	outcode2 = 0;
    register int	outside;
    
    fpoint_t	tmp;
    int		dx;
    int		dy;

    
#define DOOUTCODE(oc, mx, my) \
    (oc) = 0; \
    if ((my) < 0) (oc) |= TOP; \
    else if ((my) >= f_h) (oc) |= BOTTOM; \
    if ((mx) < 0) (oc) |= LEFT; \
    else if ((mx) >= f_w) (oc) |= RIGHT;

    
    // do trivial rejects and outcodes
    if (ml->a.y > m_y2)
	outcode1 = TOP;
    else if (ml->a.y < m_y)
	outcode1 = BOTTOM;

    if (ml->b.y > m_y2)
	outcode2 = TOP;
    else if (ml->b.y < m_y)
	outcode2 = BOTTOM;
    
    if (outcode1 & outcode2)
	return false; // trivially outside

    if (ml->a.x < m_x)
	outcode1 |= LEFT;
    else if (ml->a.x > m_x2)
	outcode1 |= RIGHT;
    
    if (ml->b.x < m_x)
	outcode2 |= LEFT;
    else if (ml->b.x > m_x2)
	outcode2 |= RIGHT;
    
    if (outcode1 & outcode2)
	return false; // trivially outside

    // transform to frame-buffer coordinates.
    fl->a.x = CXMTOF(ml->a.x);
    fl->a.y = CYMTOF(ml->a.y);
    fl->b.x = CXMTOF(ml->b.x);
    fl->b.y = CYMTOF(ml->b.y);

    DOOUTCODE(outcode1, fl->a.x, fl->a.y);
    DOOUTCODE(outcode2, fl->b.x, fl->b.y);

    if (outcode1 & outcode2)
	return false;

    while (outcode1 | outcode2)
    {
	// may be partially inside box
	// find an outside point
	if (outcode1)
	    outside = outcode1;
	else
	    outside = outcode2;
	
	// clip to each side
	if (outside & TOP)
	{
	    dy = fl->a.y - fl->b.y;
	    dx = fl->b.x - fl->a.x;
	    tmp.x = fl->a.x + (dx*(fl->a.y))/dy;
	    tmp.y = 0;
	}
	else if (outside & BOTTOM)
	{
	    dy = fl->a.y - fl->b.y;
	    dx = fl->b.x - fl->a.x;
	    tmp.x = fl->a.x + (dx*(fl->a.y-f_h))/dy;
	    tmp.y = f_h-1;
	}
	else if (outside & RIGHT)
	{
	    dy = fl->b.y - fl->a.y;
	    dx = fl->b.x - fl->a.x;
	    tmp.y = fl->a.y + (dy*(f_w-1 - fl->a.x))/dx;
	    tmp.x = f_w-1;
	}
	else if (outside & LEFT)
	{
	    dy = fl->b.y - fl->a.y;
	    dx = fl->b.x - fl->a.x;
	    tmp.y = fl->a.y + (dy*(-fl->a.x))/dx;
	    tmp.x = 0;
	}
        else
        {
            tmp.x = 0;
            tmp.y = 0;
        }

	if (outside == outcode1)
	{
	    fl->a = tmp;
	    DOOUTCODE(outcode1, fl->a.x, fl->a.y);
	}
	else
	{
	    fl->b = tmp;
	    DOOUTCODE(outcode2, fl->b.x, fl->b.y);
	}
	
	if (outcode1 & outcode2)
	    return false; // trivially outside
    }

    return true;
}
#undef DOOUTCODE


//
// Classic Bresenham w/ whatever optimizations needed for speed
//
void
AM_drawFline
( fline_t*	fl,
  int		color )
{
    register int x;
    register int y;
    register int dx;
    register int dy;
    register int sx;
    register int sy;
    register int ax;
    register int ay;
    register int d;
    
    static int fuck = 0;

    // For debugging only
    if (      fl->a.x < 0 || fl->a.x >= f_w
	   || fl->a.y < 0 || fl->a.y >= f_h
	   || fl->b.x < 0 || fl->b.x >= f_w
	   || fl->b.y < 0 || fl->b.y >= f_h)
    {
        DEH_fprintf(stderr, "fuck %d \r", fuck++);
	return;
    }

#define PUTDOT(xx,yy,cc) fb[(yy)*f_w+(xx)]=(cc)

    dx = fl->b.x - fl->a.x;
    ax = 2 * (dx<0 ? -dx : dx);
    sx = dx<0 ? -1 : 1;

    dy = fl->b.y - fl->a.y;
    ay = 2 * (dy<0 ? -dy : dy);
    sy = dy<0 ? -1 : 1;

    x = fl->a.x;
    y = fl->a.y;

    if (ax > ay)
    {
	d = ay - ax/2;
	while (1)
	{
	    PUTDOT(x,y,color);
	    if (x == fl->b.x) return;
	    if (d>=0)
	    {
		y += sy;
		d -= ax;
	    }
	    x += sx;
	    d += ay;
	}
    }
    else
    {
	d = ax - ay/2;
	while (1)
	{
	    PUTDOT(x, y, color);
	    if (y == fl->b.y) return;
	    if (d >= 0)
	    {
		x += sx;
		d -= ay;
	    }
	    y += sy;
	    d += ax;
	}
    }
}


//
// Clip lines, draw visible part sof lines.
//
void
AM_drawMline
( mline_t*	ml,
  int		color )
{
    static fline_t fl;

    if (AM_clipMline(ml, &fl))
	AM_drawFline(&fl, color); // draws it on frame buffer using fb coords
}



//
// Draws flat (floor/ceiling tile) aligned grid lines.
//
void AM_drawGrid(int color)
{
    fixed_t x, y;
    fixed_t start, end;
    mline_t ml;

    // Figure out start of vertical gridlines
    start = m_x;
    if ((start-bmaporgx)%(MAPBLOCKUNITS<<FRACBITS))
	start += (MAPBLOCKUNITS<<FRACBITS)
	    - ((start-bmaporgx)%(MAPBLOCKUNITS<<FRACBITS));
    end = m_x + m_w;

    // draw vertical gridlines
    ml.a.y = m_y;
    ml.b.y = m_y+m_h;
    for (x=start; x<end; x+=(MAPBLOCKUNITS<<FRACBITS))
    {
	ml.a.x = x;
	ml.b.x = x;
	AM_drawMline(&ml, color);
    }

    // Figure out start of horizontal gridlines
    start = m_y;
    if ((start-bmaporgy)%(MAPBLOCKUNITS<<FRACBITS))
	start += (MAPBLOCKUNITS<<FRACBITS)
	    - ((start-bmaporgy)%(MAPBLOCKUNITS<<FRACBITS));
    end = m_y + m_h;

    // draw horizontal gridlines
    ml.a.x = m_x;
    ml.b.x = m_x + m_w;
    for (y=start; y<end; y+=(MAPBLOCKUNITS<<FRACBITS))
    {
	ml.a.y = y;
	ml.b.y = y;
	AM_drawMline(&ml, color);
    }

}

//
// Determines visible lines, draws them.
// This is LineDef based, not LineSeg based.
//
void AM_drawWalls(void)
{
    int i;
    static mline_t l;

    for (i=0;i<numlines;i++)
    {
	l.a.x = lines[i].v1->x;
	l.a.y = lines[i].v1->y;
	l.b.x = lines[i].v2->x;
	l.b.y = lines[i].v2->y;
	if (cheating || (lines[i].flags & ML_MAPPED))
	{
	    if ((lines[i].flags & LINE_NEVERSEE) && !cheating)
		continue;
	    if (!lines[i].backsector)
	    {
		AM_drawMline(&l, WALLCOLORS+lightlev);
	    }
	    else
	    {
		if (lines[i].special == 39)
		{ // teleporters
		    AM_drawMline(&l, WALLCOLORS+WALLRANGE/2);
		}
		else if (lines[i].flags & ML_SECRET) // secret door
		{
		    if (cheating) AM_drawMline(&l, SECRETWALLCOLORS + lightlev);
		    else AM_drawMline(&l, WALLCOLORS+lightlev);
		}
		else if (lines[i].backsector->floorheight
			   != lines[i].frontsector->floorheight) {
		    AM_drawMline(&l, FDWALLCOLORS + lightlev); // floor level change
		}
		else if (lines[i].backsector->ceilingheight
			   != lines[i].frontsector->ceilingheight) {
		    AM_drawMline(&l, CDWALLCOLORS+lightlev); // ceiling level change
		}
		else if (cheating) {
		    AM_drawMline(&l, TSWALLCOLORS+lightlev);
		}
	    }
	}
	else if (plr->powers[pw_allmap])
	{
	    if (!(lines[i].flags & LINE_NEVERSEE)) AM_drawMline(&l, GRAYS+3);
	}
    }
}


//
// Rotation in 2D.
// Used to rotate player arrow line character.
//
void
AM_rotate
( fixed_t*	x,
  fixed_t*	y,
  angle_t	a )
{
    fixed_t tmpx;

    tmpx =
	FixedMul(*x,finecosine[a>>ANGLETOFINESHIFT])
	- FixedMul(*y,finesine[a>>ANGLETOFINESHIFT]);
    
    *y   =
	FixedMul(*x,finesine[a>>ANGLETOFINESHIFT])
	+ FixedMul(*y,finecosine[a>>ANGLETOFINESHIFT]);

    *x = tmpx;
}

void
AM_drawLineCharacter
( mline_t*	lineguy,
  int		lineguylines,
  fixed_t	scale,
  angle_t	angle,
  int		color,
  fixed_t	x,
  fixed_t	y )
{
    int		i;
    mline_t	l;

    for (i=0;i<lineguylines;i++)
    {
	l.a.x = lineguy[i].a.x;
	l.a.y = lineguy[i].a.y;

	if (scale)
	{
	    l.a.x = FixedMul(scale, l.a.x);
	    l.a.y = FixedMul(scale, l.a.y);
	}

	if (angle)
	    AM_rotate(&l.a.x, &l.a.y, angle);

	l.a.x += x;
	l.a.y += y;

	l.b.x = lineguy[i].b.x;
	l.b.y = lineguy[i].b.y;

	if (scale)
	{
	    l.b.x = FixedMul(scale, l.b.x);
	    l.b.y = FixedMul(scale, l.b.y);
	}

	if (angle)
	    AM_rotate(&l.b.x, &l.b.y, angle);
	
	l.b.x += x;
	l.b.y += y;

	AM_drawMline(&l, color);
    }
}

void AM_drawPlayers(void)
{
    int		i;
    player_t*	p;
    static int 	their_colors[] = { GREENS, GRAYS, BROWNS, REDS };
    int		their_color = -1;
    int		color;

    if (!netgame)
    {
	if (cheating)
	    AM_drawLineCharacter
		(cheat_player_arrow, arrlen(cheat_player_arrow), 0,
		 plr->mo->angle, WHITE, plr->mo->x, plr->mo->y);
	else
	    AM_drawLineCharacter
		(player_arrow, arrlen(player_arrow), 0, plr->mo->angle,
		 WHITE, plr->mo->x, plr->mo->y);
	return;
    }

    for (i=0;i<MAXPLAYERS;i++)
    {
	their_color++;
	p = &players[i];

	if ( (deathmatch && !singledemo) && p != plr)
	    continue;

	if (!playeringame[i])
	    continue;

	if (p->powers[pw_invisibility])
	    color = 246; // *close* to black
	else
	    color = their_colors[their_color];
	
	AM_drawLineCharacter
	    (player_arrow, arrlen(player_arrow), 0, p->mo->angle,
	     color, p->mo->x, p->mo->y);
    }

}

void
AM_drawThings
( int	colors,
  int 	colorrange)
{
    int		i;
    mobj_t*	t;

    for (i=0;i<numsectors;i++)
    {
	t = sectors[i].thinglist;
	while (t)
	{
	    AM_drawLineCharacter
		(thintriangle_guy, arrlen(thintriangle_guy),
		 16<<FRACBITS, t->angle, colors+lightlev, t->x, t->y);
	    t = t->snext;
	}
    }
}

void AM_drawMarks(void)
{
    int i, fx, fy, w, h;

    for (i=0;i<AM_NUMMARKPOINTS;i++)
    {
	if (markpoints[i].x != -1)
	{
	    //      w = SHORT(marknums[i]->width);
	    //      h = SHORT(marknums[i]->height);
	    w = 5; // because something's wrong with the wad, i guess
	    h = 6; // because something's wrong with the wad, i guess
	    fx = CXMTOF(markpoints[i].x);
	    fy = CYMTOF(markpoints[i].y);
	    if (fx >= f_x && fx <= f_w - w && fy >= f_y && fy <= f_h - h)
		V_DrawPatch(fx, fy, marknums[i]);
	}
    }

}

void AM_drawCrosshair(int color)
{
    fb[(f_w*(f_h+1))/2] = color; // single point for now

}

void AM_Drawer (void)
{
    if (!automapactive) return;

    AM_clearFB(BACKGROUND);
    if (grid)
	AM_drawGrid(GRIDCOLORS);
    AM_drawWalls();
    AM_drawPlayers();
    if (cheating==2)
	AM_drawThings(THINGCOLORS, THINGRANGE);
    AM_drawCrosshair(XHAIRCOLORS);

    AM_drawMarks();

    V_MarkRect(f_x, f_y, f_w, f_h);

}
