server/common/los.C

/*
 * This file is part of Deliantra, the Roguelike Realtime MMORPG.
 * 
 * Copyright (©) 2005,2006,2007,2008,2009 Marc Alexander Lehmann / Robin Redeker / the Deliantra team
 * Copyright (©) 2002,2007 Mark Wedel & Crossfire Development Team
 * Copyright (©) 1992,2007 Frank Tore Johansen
 * 
 * Deliantra 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 3 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, see <http://www.gnu.org/licenses/>.
 * 
 * The authors can be reached via e-mail to <support@deliantra.net>
 */

#include <global.h>
#include <cmath>

#define SEE_IN_DARK_RADIUS 2
#define MAX_VISION 10 // maximum visible radius

// los flags
enum {
  FLG_XI      = 0x01, // we have an x-parent
  FLG_YI      = 0x02, // we have an y-parent
  FLG_BLOCKED = 0x04, // this space blocks the view
  FLG_QUEUED  = 0x80  // already queued in queue, or border
};

struct los_info
{
  uint8 flags;   // FLG_xxx
  uint8 culled;  // culled from "tree"
  uint8 visible;
  uint8 pad0;

  sint8 xo, yo;  // obscure angle
  sint8 xe, ye;  // angle deviation
};

// temporary storage for the los algorithm,
// one los_info for each lightable map space
static los_info los[MAP_CLIENT_X][MAP_CLIENT_Y];

struct point
{
  sint8 x, y;
};

// minimum size, but must be a power of two
#define QUEUE_LENGTH ((MAP_CLIENT_X + MAP_CLIENT_Y) * 2)

// a queue of spaces to calculate
static point queue [QUEUE_LENGTH];
static int q1, q2; // queue start, end

/*
 * Clears/initialises the los-array associated to the player
 * controlling the object.
 */
void
player::clear_los (sint8 value)
{
  memset (los, value, sizeof (los));
}

// enqueue a single mapspace, but only if it hasn't
// been enqueued yet.
static void
enqueue (sint8 dx, sint8 dy, uint8 flags = 0)
{
  sint8 x = LOS_X0 + dx;
  sint8 y = LOS_Y0 + dy;

  los_info &l = los[x][y];

  l.flags |= flags;

  if (l.flags & FLG_QUEUED)
    return;

  l.flags |= FLG_QUEUED;

  queue[q1].x = dx;
  queue[q1].y = dy;

  q1 = (q1 + 1) & (QUEUE_LENGTH - 1);
}

// run the los algorithm
// this is a variant of a spiral los algorithm taken from
// http://www.geocities.com/temerra/los_rays.html
// which has been simplified and changed considerably, but
// still is basically the same algorithm.
static void
calculate_los (player *pl)
{
  {
    memset (los, 0, sizeof (los));

    // we keep one line for ourselves, for the border flag
    // so the client area is actually MAP_CLIENT_(X|Y) - 2
    int half_x = min (LOS_X0 - 1, pl->ns->mapx / 2);
    int half_y = min (LOS_Y0 - 1, pl->ns->mapy / 2);

    // create borders, the corners are not touched
    for (int dx = -half_x; dx <= half_x; ++dx)
      los [dx + LOS_X0][LOS_Y0 - (half_y + 1)].flags =
      los [dx + LOS_X0][LOS_Y0 + (half_y + 1)].flags = FLG_QUEUED;

    for (int dy = -half_y; dy <= half_y; ++dy)
      los [LOS_X0 - (half_x + 1)][dy + LOS_Y0].flags =
      los [LOS_X0 + (half_x + 1)][dy + LOS_Y0].flags = FLG_QUEUED;

    // now reset the los area and also add blocked flags
    // which supposedly is faster than doing it inside the
    // spiral path algorithm below, except when very little
    // area is visible, in which case it is slower. which evens
    // out los calculation times between large and small los maps.
    // apply_lights also iterates over this area, maybe these
    // two passes could be combined somehow.
    unordered_mapwalk (pl->observe, -half_x, -half_y, half_x, half_y)
      {
        los_info &l = los [LOS_X0 + dx][LOS_Y0 + dy];
        l.flags = m->at (nx, ny).flags () & P_BLOCKSVIEW ? FLG_BLOCKED : 0;
      }
  }

  q1 = 0; q2 = 0; // initialise queue, not strictly required
  enqueue (0, 0); // enqueue center

  // treat the origin specially
  los[LOS_X0][LOS_Y0].visible = 1;
  pl->los[LOS_X0][LOS_Y0] = 0;

  // loop over all enqueued points until the queue is empty
  // the order in which this is done ensures that we
  // never touch a mapspace whose input spaces we haven't checked
  // yet.
  while (q1 != q2)
    {
      sint8 dx = queue[q2].x;
      sint8 dy = queue[q2].y;

      q2 = (q2 + 1) & (QUEUE_LENGTH - 1);

      sint8 x = LOS_X0 + dx;
      sint8 y = LOS_Y0 + dy;

      los_info &l = los[x][y];

      if (expect_true (l.flags & (FLG_XI | FLG_YI)))
        {
          l.culled = 1;
          l.xo = l.yo = l.xe = l.ye = 0;

          // check contributing spaces, first horizontal
          if (expect_true (l.flags & FLG_XI))
            {
              los_info *xi = &los[x - sign (dx)][y];

              // don't cull unless obscured
              l.culled &= !xi->visible;

              /* merge input space */
              if (expect_false (xi->xo || xi->yo))
                {
                  // The X input can provide two main pieces of information: 
                  // 1. Progressive X obscurity.
                  // 2. Recessive Y obscurity.
                          
                  // Progressive X obscurity, favouring recessive input angle
                  if (xi->xe > 0 && l.xo == 0)
                    {
                      l.xe = xi->xe - xi->yo;
                      l.ye = xi->ye + xi->yo;
                      l.xo = xi->xo;
                      l.yo = xi->yo;
                    }

                  // Recessive Y obscurity
                  if (xi->ye <= 0 && xi->yo > 0 && xi->xe > 0)
                    {
                      l.ye = xi->yo + xi->ye;
                      l.xe = xi->xe - xi->yo;
                      l.xo = xi->xo;
                      l.yo = xi->yo;
                    }
                }
            }
                
          // check contributing spaces, last vertical, identical structure
          if (expect_true (l.flags & FLG_YI))
            {
              los_info *yi = &los[x][y - sign (dy)];

              // don't cull unless obscured
              l.culled &= !yi->visible;

              /* merge input space */
              if (expect_false (yi->yo || yi->xo))
                {
                  // The Y input can provide two main pieces of information: 
                  // 1. Progressive Y obscurity.
                  // 2. Recessive X obscurity.
                          
                  // Progressive Y obscurity, favouring recessive input angle
                  if (yi->ye > 0 && l.yo == 0)
                    {
                      l.ye = yi->ye - yi->xo;
                      l.xe = yi->xe + yi->xo;
                      l.yo = yi->yo;
                      l.xo = yi->xo;
                    }

                  // Recessive X obscurity
                  if (yi->xe <= 0 && yi->xo > 0 && yi->ye > 0)
                    {
                      l.xe = yi->xo + yi->xe;
                      l.ye = yi->ye - yi->xo;
                      l.yo = yi->yo;
                      l.xo = yi->xo;
                    }
                }
            }

          if (l.flags & FLG_BLOCKED)
            {
              l.xo = l.xe = abs (dx);
              l.yo = l.ye = abs (dy);

              // we obscure dependents, but might be visible
              // copy the los from the square towards the player,
              // so outward diagonal corners are lit.
              pl->los[x][y] = los[x - sign0 (dx)][y - sign0 (dy)].visible ? 0 : LOS_BLOCKED;

              l.visible = false;
            }
          else
            {
              // we are not blocked, so calculate visibility, by checking
              // whether we are inside or outside the shadow
              l.visible = (l.xe <= 0 || l.xe > l.xo)
                       && (l.ye <= 0 || l.ye > l.yo);

              pl->los[x][y] = l.culled  ? LOS_BLOCKED
                            : l.visible ? 0
                                        : 3;
            }

        }

      // Expands by the unit length in each component's current direction.
      // If a component has no direction, then it is expanded in both of its 
      // positive and negative directions.
      if (!l.culled)
        {
          if (dx >= 0) enqueue (dx + 1, dy, FLG_XI);
          if (dx <= 0) enqueue (dx - 1, dy, FLG_XI);
          if (dy >= 0) enqueue (dx, dy + 1, FLG_YI);
          if (dy <= 0) enqueue (dx, dy - 1, FLG_YI);
        }
    }
}

/* radius, distance => lightness adjust */
static sint8 light_atten[MAX_LIGHT_RADIUS * 2 + 1][MAX_LIGHT_RADIUS * 3 / 2 + 1];
static sint8 vision_atten[MAX_VISION + 1][MAX_VISION * 3 / 2 + 1];

static struct los_init
{
  los_init ()
  {
    assert (("QUEUE_LENGTH, MAP_CLIENT_X and MAP_CLIENT_Y *must* be powers of two",
             !(QUEUE_LENGTH & (QUEUE_LENGTH - 1))));

    /* for lights */
    for (int radius = -MAX_LIGHT_RADIUS; radius <= MAX_LIGHT_RADIUS; ++radius)
      for (int distance = 0; distance <= MAX_LIGHT_RADIUS * 3 / 2; ++distance)
        {
          // max intensity
          int intensity = min (LOS_MAX, abs (radius) + 1);

          // actual intensity
          intensity = max (0, lerp_ru (distance, 0, abs (radius) + 1, intensity, 0));

          light_atten [radius + MAX_LIGHT_RADIUS][distance] = radius < 0
            ? min (3, intensity)
            : LOS_MAX - intensity;
        }

    /* for general vision */
    for (int radius = 0; radius <= MAX_VISION; ++radius)
      for (int distance = 0; distance <= MAX_VISION * 3 / 2; ++distance)
        vision_atten [radius][distance] = distance <= radius ? clamp (lerp (radius, 0, MAX_DARKNESS, 3, 0), 0, 3) : 4;
  }
} los_init;

sint8
los_brighten (sint8 b, sint8 l)
{
  return b == LOS_BLOCKED ? b : min (b, l);
}

sint8
los_darken (sint8 b, sint8 l)
{
  return max (b, l);
}

template<sint8 change_it (sint8, sint8)>
static void
apply_light (player *pl, int dx, int dy, int light, const sint8 *atten_table)
{
  // min or max the circular area around basex, basey
  dx += LOS_X0;
  dy += LOS_Y0;

  int hx = pl->ns->mapx / 2;
  int hy = pl->ns->mapy / 2;

  int ax0 = max (LOS_X0 - hx, dx - light);
  int ay0 = max (LOS_Y0 - hy, dy - light);
  int ax1 = min (dx + light, LOS_X0 + hx);
  int ay1 = min (dy + light, LOS_Y0 + hy);

  for (int ax = ax0; ax <= ax1; ax++)
    for (int ay = ay0; ay <= ay1; ay++)
      pl->los[ax][ay] =
        change_it (pl->los[ax][ay], atten_table [idistance (ax - dx, ay - dy)]);
}

/* add light, by finding all (non-null) nearby light sources, then 
 * mark those squares specially.
 */
static void
apply_lights (player *pl)
{
  object *op = pl->observe;
  int darklevel = op->map->darklevel ();

  int half_x = pl->ns->mapx / 2;
  int half_y = pl->ns->mapy / 2;

  int pass2 = 0; // negative lights have an extra pass

  maprect *rects = pl->observe->map->split_to_tiles (
    pl->observe->x - half_x - MAX_LIGHT_RADIUS,
    pl->observe->y - half_y - MAX_LIGHT_RADIUS,
    pl->observe->x + half_x + MAX_LIGHT_RADIUS + 1,
    pl->observe->y + half_y + MAX_LIGHT_RADIUS + 1
  );

  /* If the player can see in the dark, increase light/vision radius */
  int bonus = op->flag [FLAG_SEE_IN_DARK] ? SEE_IN_DARK_RADIUS : 0;

  if (!darklevel)
    pass2 = 1;
  else
    {
      /* first, make everything totally dark */
      for (int dx = -half_x; dx <= half_x; dx++)
        for (int dy = -half_x; dy <= half_y; dy++)
          max_it (pl->los[dx + LOS_X0][dy + LOS_Y0], LOS_MAX);

      /*
       * Only process the area of interest.
       * the basex, basey values represent the position in the op->contr->los
       * array. Its easier to just increment them here (and start with the right
       * value) than to recalculate them down below.
       */
      for (maprect *r = rects; r->m; ++r)
        rect_mapwalk (r, 0, 0)
          {
            mapspace &ms = m->at (nx, ny);
            ms.update ();
            sint8 light = ms.light;

            if (expect_false (light))
              if (light < 0)
                pass2 = 1;
              else
                {
                  light = clamp (light + bonus, 0, MAX_LIGHT_RADIUS);
                  apply_light<los_brighten> (pl, dx - pl->observe->x, dy - pl->observe->y, light, light_atten [light + MAX_LIGHT_RADIUS]);
                }
          }

      /* grant some vision to the player, based on outside, outdoor, and darklevel */
      {
        int light;

        if (!op->map->outdoor) // not outdoor, darkness becomes light radius
          light = MAX_DARKNESS - op->map->darkness;
        else if (op->map->darkness > 0) // outdoor and darkness > 0 => use darkness as max radius
          light = lerp_rd (maptile::outdoor_darkness + 0, 0, MAX_DARKNESS, MAX_DARKNESS - op->map->darkness, 0);
        else // outdoor and darkness <= 0 => start wide and decrease quickly
          light = lerp (maptile::outdoor_darkness + op->map->darkness, 0, MAX_DARKNESS, MAX_VISION, 2);

        light = clamp (light + bonus, 0, MAX_VISION);

        apply_light<los_brighten> (pl, 0, 0, light, vision_atten [light]);
      }
    }

  // possibly do 2nd pass for rare negative glow radii
  // for effect, those are always considered to be stronger than anything else
  // but they can't darken a place completely
  if (pass2)
    for (maprect *r = rects; r->m; ++r)
      rect_mapwalk (r, 0, 0)
        {
          mapspace &ms = m->at (nx, ny);
          ms.update ();
          sint8 light = ms.light;

          if (expect_false (light < 0))
            {
              light = clamp (light - bonus, 0, MAX_DARKNESS);
              apply_light<los_darken> (pl, dx - pl->observe->x, dy - pl->observe->y, -light, light_atten [light + MAX_LIGHT_RADIUS]);
            }
        }
}

/* blinded_sight() - sets all viewable squares to blocked except 
 * for the one the central one that the player occupies.  A little
 * odd that you can see yourself (and what your standing on), but
 * really need for any reasonable game play.
 */
static void
blinded_sight (player *pl)
{
  pl->los[LOS_X0][LOS_Y0] = 1;
}

/*
 * update_los() recalculates the array which specifies what is
 * visible for the given player-object.
 */
void
player::update_los ()
{
  if (ob->flag [FLAG_REMOVED])//D really needed?
    return;

  if (ob->flag [FLAG_WIZLOOK])
    clear_los (0);
  else if (observe->flag [FLAG_BLIND])      /* player is blind */
    {
      clear_los ();
      blinded_sight (this);
    }
  else
    {
      clear_los ();
      calculate_los (this);
      apply_lights (this);
    }

  if (observe->flag [FLAG_XRAYS])
    for (int dx = -2; dx <= 2; dx++)
      for (int dy = -2; dy <= 2; dy++)
        min_it (los[dx + LOS_X0][dy + LOS_Y0], 1);
}

/* update all_map_los is like update_all_los below,
 * but updates everyone on the map, no matter where they
 * are. This generally should not be used, as a per
 * specific map change doesn't make much sense when tiling
 * is considered (lowering darkness would certainly be a
 * strange effect if done on a tile map, as it makes
 * the distinction between maps much more obvious to the
 * players, which is should not be.
 * Currently, this function is called from the
 * change_map_light function
 */
void
update_all_map_los (maptile *map)
{
  for_all_players_on_map (pl, map)
    pl->do_los = 1;
}

/*
 * This function makes sure that update_los() will be called for all
 * players on the given map within the next frame.
 * It is triggered by removal or inserting of objects which blocks
 * the sight in the map.
 * Modified by MSW 2001-07-12 to take a coordinate of the changed
 * position, and to also take map tiling into account.  This change
 * means that just being on the same map is not sufficient - the
 * space that changes must be withing your viewable area.
 *
 * map is the map that changed, x and y are the coordinates.
 */
void
update_all_los (const maptile *map, int x, int y)
{
  map->at (x, y).invalidate ();

  for_all_players (pl)
    {
      /* Player should not have a null map, but do this
       * check as a safety
       */
      if (!pl->ob || !pl->ob->map || !pl->ns)
        continue;

      rv_vector rv;

      get_rangevector_from_mapcoord (map, x, y, pl->ob, &rv);
      
      if ((abs (rv.distance_x) <= pl->ns->mapx / 2) && (abs (rv.distance_y) <= pl->ns->mapy / 2))
        pl->do_los = 1;
    }
}

static const int season_darkness[5][HOURS_PER_DAY] = {
  /*0  1  2  3  4  5  6  7  8  9 10 11 12 13 14  1  2  3  4  5  6  7  8  9 10 11 12 13 */
  { 5, 5, 4, 4, 4, 4, 4, 3, 3, 3, 3, 2, 2, 1, 1, 0, 0, 0, 0, 1, 2, 2, 2, 3, 3, 4, 4, 5 },
  { 5, 5, 4, 4, 4, 4, 3, 3, 3, 2, 2, 1, 1, 0, 0, 0, 0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4 },
  { 5, 4, 4, 4, 4, 3, 3, 2, 2, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 2, 2, 3, 4, 4 },
  { 4, 4, 4, 4, 3, 3, 2, 2, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 2, 2, 3, 4 },
  { 5, 5, 4, 4, 4, 3, 3, 3, 2, 2, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4 }
};

/*
 * Tell players the time and compute the darkness level for all maps in the game.
 * MUST be called exactly once per hour.
 */
void
maptile::adjust_daylight ()
{
  timeofday_t tod;

  get_tod (&tod);

  // log the time to log-1 every hour, and to chat every day
  {
    char todbuf[512];

    format_tod (todbuf, sizeof (todbuf), &tod);

    for_all_players (pl)
      pl->ns->send_msg (NDI_GREY, tod.hour == 15 ? CHAT_CHANNEL : LOG_CHANNEL, todbuf);
  }

  /* If the light level isn't changing, no reason to do all
   * the work below.
   */
  sint8 new_darkness = season_darkness[tod.season][tod.hour];

  if (new_darkness == maptile::outdoor_darkness)
    return;

  new_draw_info (NDI_GREY | NDI_UNIQUE | NDI_ALL, 1, 0,
                 new_darkness > maptile::outdoor_darkness
                 ? "It becomes darker."
                 : "It becomes brighter.");

  maptile::outdoor_darkness = new_darkness;

  // we simply update the los for all players, which is unnecessarily
  // costly, but should do for the moment.
  for_all_players (pl)
    pl->do_los = 1;
}

/*
 * make_sure_seen: The object is supposed to be visible through walls, thus
 * check if any players are nearby, and edit their LOS array.
 */
void
make_sure_seen (const object *op)
{
  for_all_players (pl)
    if (pl->ob->map == op->map &&
        pl->ob->y - pl->ns->mapy / 2 <= op->y &&
        pl->ob->y + pl->ns->mapy / 2 >= op->y && pl->ob->x - pl->ns->mapx / 2 <= op->x && pl->ob->x + pl->ns->mapx / 2 >= op->x)
      pl->los[op->x - pl->ob->x + LOS_X0][op->y - pl->ob->y + LOS_Y0] = 0;
}

/*
 * make_sure_not_seen: The object which is supposed to be visible through
 * walls has just been removed from the map, so update the los of any
 * players within its range
 */
void
make_sure_not_seen (const object *op)
{
  for_all_players (pl)
    if (pl->ob->map == op->map &&
        pl->ob->y - pl->ns->mapy / 2 <= op->y &&
        pl->ob->y + pl->ns->mapy / 2 >= op->y && pl->ob->x - pl->ns->mapx / 2 <= op->x && pl->ob->x + pl->ns->mapx / 2 >= op->x)
      pl->do_los = 1;
}

Revision:	1.61
Committed:	Tue May 5 04:51:56 2009 UTC (15 years ago) by root
Content type:	text/plain
Branch:	MAIN
CVS Tags:	rel-2_80, rel-2_79
Changes since 1.60:	+7 -53 lines
Log Message:	adjust los lightness a bit
#	User	Rev	Content
1	elmex	1.1	/*
2	root	1.29	* This file is part of Deliantra, the Roguelike Realtime MMORPG.
3	pippijn	1.19	*
4	root	1.60	* Copyright (©) 2005,2006,2007,2008,2009 Marc Alexander Lehmann / Robin Redeker / the Deliantra team
5	root	1.26	* Copyright (©) 2002,2007 Mark Wedel & Crossfire Development Team
6			* Copyright (©) 1992,2007 Frank Tore Johansen
7	pippijn	1.19	*
8	root	1.29	* Deliantra is free software: you can redistribute it and/or modify
9	root	1.28	* it under the terms of the GNU General Public License as published by
10			* the Free Software Foundation, either version 3 of the License, or
11			* (at your option) any later version.
12	pippijn	1.19	*
13	root	1.28	* This program is distributed in the hope that it will be useful,
14			* but WITHOUT ANY WARRANTY; without even the implied warranty of
15			* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16			* GNU General Public License for more details.
17	pippijn	1.19	*
18	root	1.28	* You should have received a copy of the GNU General Public License
19			* along with this program. If not, see <http://www.gnu.org/licenses/>.
20	root	1.26	*
21	root	1.29	* The authors can be reached via e-mail to <support@deliantra.net>
22	pippijn	1.19	*/
23	elmex	1.1
24			#include <global.h>
25	root	1.41	#include <cmath>
26	elmex	1.1
27	root	1.56	#define SEE_IN_DARK_RADIUS 2
28	root	1.57	#define MAX_VISION 10 // maximum visible radius
29	root	1.51
30	root	1.49	// los flags
31	root	1.41	enum {
32	root	1.49	FLG_XI = 0x01, // we have an x-parent
33			FLG_YI = 0x02, // we have an y-parent
34			FLG_BLOCKED = 0x04, // this space blocks the view
35			FLG_QUEUED = 0x80 // already queued in queue, or border
36	root	1.41	};
37
38			struct los_info
39			{
40	root	1.49	uint8 flags; // FLG_xxx
41			uint8 culled; // culled from "tree"
42			uint8 visible;
43			uint8 pad0;
44
45	root	1.43	sint8 xo, yo; // obscure angle
46			sint8 xe, ye; // angle deviation
47	root	1.41	};
48
49			// temporary storage for the los algorithm,
50			// one los_info for each lightable map space
51			static los_info los[MAP_CLIENT_X][MAP_CLIENT_Y];
52
53			struct point
54			{
55			sint8 x, y;
56			};
57
58			// minimum size, but must be a power of two
59			#define QUEUE_LENGTH ((MAP_CLIENT_X + MAP_CLIENT_Y) * 2)
60
61			// a queue of spaces to calculate
62			static point queue [QUEUE_LENGTH];
63			static int q1, q2; // queue start, end
64	elmex	1.1
65			/*
66	root	1.41	* Clears/initialises the los-array associated to the player
67			* controlling the object.
68	elmex	1.1	*/
69	root	1.41	void
70	root	1.42	player::clear_los (sint8 value)
71	root	1.41	{
72	root	1.42	memset (los, value, sizeof (los));
73	root	1.41	}
74	elmex	1.1
75	root	1.41	// enqueue a single mapspace, but only if it hasn't
76			// been enqueued yet.
77	root	1.4	static void
78	root	1.41	enqueue (sint8 dx, sint8 dy, uint8 flags = 0)
79	root	1.4	{
80	root	1.41	sint8 x = LOS_X0 + dx;
81			sint8 y = LOS_Y0 + dy;
82
83			los_info &l = los[x][y];
84
85			l.flags \|= flags;
86
87	root	1.49	if (l.flags & FLG_QUEUED)
88	root	1.41	return;
89	elmex	1.1
90	root	1.49	l.flags \|= FLG_QUEUED;
91	root	1.41
92			queue[q1].x = dx;
93			queue[q1].y = dy;
94	elmex	1.1
95	root	1.41	q1 = (q1 + 1) & (QUEUE_LENGTH - 1);
96	elmex	1.1	}
97
98	root	1.41	// run the los algorithm
99			// this is a variant of a spiral los algorithm taken from
100			// http://www.geocities.com/temerra/los_rays.html
101			// which has been simplified and changed considerably, but
102			// still is basically the same algorithm.
103			static void
104	root	1.48	calculate_los (player *pl)
105	root	1.4	{
106	root	1.49	{
107	root	1.52	memset (los, 0, sizeof (los));
108
109	root	1.49	// we keep one line for ourselves, for the border flag
110			// so the client area is actually MAP_CLIENT_(X\|Y) - 2
111			int half_x = min (LOS_X0 - 1, pl->ns->mapx / 2);
112			int half_y = min (LOS_Y0 - 1, pl->ns->mapy / 2);
113
114			// create borders, the corners are not touched
115			for (int dx = -half_x; dx <= half_x; ++dx)
116			los [dx + LOS_X0][LOS_Y0 - (half_y + 1)].flags =
117			los [dx + LOS_X0][LOS_Y0 + (half_y + 1)].flags = FLG_QUEUED;
118
119			for (int dy = -half_y; dy <= half_y; ++dy)
120			los [LOS_X0 - (half_x + 1)][dy + LOS_Y0].flags =
121			los [LOS_X0 + (half_x + 1)][dy + LOS_Y0].flags = FLG_QUEUED;
122
123			// now reset the los area and also add blocked flags
124			// which supposedly is faster than doing it inside the
125			// spiral path algorithm below, except when very little
126	root	1.54	// area is visible, in which case it is slower. which evens
127	root	1.49	// out los calculation times between large and small los maps.
128			// apply_lights also iterates over this area, maybe these
129			// two passes could be combined somehow.
130	root	1.52	unordered_mapwalk (pl->observe, -half_x, -half_y, half_x, half_y)
131			{
132			los_info &l = los [LOS_X0 + dx][LOS_Y0 + dy];
133			l.flags = m->at (nx, ny).flags () & P_BLOCKSVIEW ? FLG_BLOCKED : 0;
134			}
135	root	1.49	}
136	root	1.4
137	root	1.41	q1 = 0; q2 = 0; // initialise queue, not strictly required
138			enqueue (0, 0); // enqueue center
139	root	1.4
140	root	1.41	// treat the origin specially
141			los[LOS_X0][LOS_Y0].visible = 1;
142			pl->los[LOS_X0][LOS_Y0] = 0;
143
144			// loop over all enqueued points until the queue is empty
145			// the order in which this is done ensures that we
146			// never touch a mapspace whose input spaces we haven't checked
147			// yet.
148			while (q1 != q2)
149			{
150			sint8 dx = queue[q2].x;
151			sint8 dy = queue[q2].y;
152	root	1.4
153	root	1.41	q2 = (q2 + 1) & (QUEUE_LENGTH - 1);
154	root	1.4
155	root	1.41	sint8 x = LOS_X0 + dx;
156			sint8 y = LOS_Y0 + dy;
157	elmex	1.1
158	root	1.41	los_info &l = los[x][y];
159	elmex	1.1
160	root	1.49	if (expect_true (l.flags & (FLG_XI \| FLG_YI)))
161	root	1.41	{
162			l.culled = 1;
163	root	1.49	l.xo = l.yo = l.xe = l.ye = 0;
164	elmex	1.1
165	root	1.41	// check contributing spaces, first horizontal
166	root	1.49	if (expect_true (l.flags & FLG_XI))
167	root	1.41	{
168			los_info *xi = &los[x - sign (dx)][y];
169	elmex	1.1
170	root	1.41	// don't cull unless obscured
171			l.culled &= !xi->visible;
172	elmex	1.1
173	root	1.41	/* merge input space */
174			if (expect_false (xi->xo \|\| xi->yo))
175			{
176			// The X input can provide two main pieces of information:
177			// 1. Progressive X obscurity.
178			// 2. Recessive Y obscurity.
179
180			// Progressive X obscurity, favouring recessive input angle
181			if (xi->xe > 0 && l.xo == 0)
182			{
183			l.xe = xi->xe - xi->yo;
184			l.ye = xi->ye + xi->yo;
185			l.xo = xi->xo;
186			l.yo = xi->yo;
187			}
188	root	1.4
189	root	1.41	// Recessive Y obscurity
190			if (xi->ye <= 0 && xi->yo > 0 && xi->xe > 0)
191			{
192			l.ye = xi->yo + xi->ye;
193			l.xe = xi->xe - xi->yo;
194			l.xo = xi->xo;
195			l.yo = xi->yo;
196			}
197			}
198			}
199
200			// check contributing spaces, last vertical, identical structure
201	root	1.49	if (expect_true (l.flags & FLG_YI))
202	root	1.41	{
203			los_info *yi = &los[x][y - sign (dy)];
204	elmex	1.1
205	root	1.41	// don't cull unless obscured
206			l.culled &= !yi->visible;
207	elmex	1.1
208	root	1.41	/* merge input space */
209			if (expect_false (yi->yo \|\| yi->xo))
210			{
211			// The Y input can provide two main pieces of information:
212			// 1. Progressive Y obscurity.
213			// 2. Recessive X obscurity.
214
215			// Progressive Y obscurity, favouring recessive input angle
216			if (yi->ye > 0 && l.yo == 0)
217			{
218			l.ye = yi->ye - yi->xo;
219			l.xe = yi->xe + yi->xo;
220			l.yo = yi->yo;
221			l.xo = yi->xo;
222			}
223	elmex	1.1
224	root	1.41	// Recessive X obscurity
225			if (yi->xe <= 0 && yi->xo > 0 && yi->ye > 0)
226			{
227			l.xe = yi->xo + yi->xe;
228			l.ye = yi->ye - yi->xo;
229			l.yo = yi->yo;
230			l.xo = yi->xo;
231			}
232			}
233			}
234	elmex	1.1
235	root	1.49	if (l.flags & FLG_BLOCKED)
236	root	1.41	{
237			l.xo = l.xe = abs (dx);
238			l.yo = l.ye = abs (dy);
239	elmex	1.1
240	root	1.41	// we obscure dependents, but might be visible
241			// copy the los from the square towards the player,
242			// so outward diagonal corners are lit.
243			pl->los[x][y] = los[x - sign0 (dx)][y - sign0 (dy)].visible ? 0 : LOS_BLOCKED;
244	root	1.49
245	root	1.41	l.visible = false;
246			}
247			else
248			{
249			// we are not blocked, so calculate visibility, by checking
250			// whether we are inside or outside the shadow
251			l.visible = (l.xe <= 0 \|\| l.xe > l.xo)
252			&& (l.ye <= 0 \|\| l.ye > l.yo);
253
254			pl->los[x][y] = l.culled ? LOS_BLOCKED
255	root	1.49	: l.visible ? 0
256	root	1.41	: 3;
257	root	1.37	}
258	root	1.41
259	root	1.37	}
260	root	1.4
261	root	1.41	// Expands by the unit length in each component's current direction.
262			// If a component has no direction, then it is expanded in both of its
263			// positive and negative directions.
264			if (!l.culled)
265			{
266	root	1.49	if (dx >= 0) enqueue (dx + 1, dy, FLG_XI);
267			if (dx <= 0) enqueue (dx - 1, dy, FLG_XI);
268			if (dy >= 0) enqueue (dx, dy + 1, FLG_YI);
269			if (dy <= 0) enqueue (dx, dy - 1, FLG_YI);
270	root	1.41	}
271			}
272	elmex	1.1	}
273
274	root	1.32	/* radius, distance => lightness adjust */
275	root	1.44	static sint8 light_atten[MAX_LIGHT_RADIUS * 2 + 1][MAX_LIGHT_RADIUS * 3 / 2 + 1];
276	root	1.57	static sint8 vision_atten[MAX_VISION + 1][MAX_VISION * 3 / 2 + 1];
277	root	1.32
278	root	1.44	static struct los_init
279	root	1.32	{
280	root	1.44	los_init ()
281	root	1.32	{
282	root	1.49	assert (("QUEUE_LENGTH, MAP_CLIENT_X and MAP_CLIENT_Y must be powers of two",
283			!(QUEUE_LENGTH & (QUEUE_LENGTH - 1))));
284
285	root	1.45	/* for lights */
286	root	1.32	for (int radius = -MAX_LIGHT_RADIUS; radius <= MAX_LIGHT_RADIUS; ++radius)
287	root	1.35	for (int distance = 0; distance <= MAX_LIGHT_RADIUS * 3 / 2; ++distance)
288	root	1.32	{
289			// max intensity
290	root	1.36	int intensity = min (LOS_MAX, abs (radius) + 1);
291	root	1.32
292			// actual intensity
293	root	1.61	intensity = max (0, lerp_ru (distance, 0, abs (radius) + 1, intensity, 0));
294	root	1.32
295	root	1.44	light_atten [radius + MAX_LIGHT_RADIUS][distance] = radius < 0
296	root	1.35	? min (3, intensity)
297	root	1.36	: LOS_MAX - intensity;
298	root	1.32	}
299	root	1.45
300			/* for general vision */
301	root	1.57	for (int radius = 0; radius <= MAX_VISION; ++radius)
302			for (int distance = 0; distance <= MAX_VISION * 3 / 2; ++distance)
303			vision_atten [radius][distance] = distance <= radius ? clamp (lerp (radius, 0, MAX_DARKNESS, 3, 0), 0, 3) : 4;
304	root	1.32	}
305	root	1.44	} los_init;
306	root	1.32
307	root	1.39	sint8
308			los_brighten (sint8 b, sint8 l)
309			{
310			return b == LOS_BLOCKED ? b : min (b, l);
311			}
312
313			sint8
314			los_darken (sint8 b, sint8 l)
315			{
316			return max (b, l);
317			}
318
319			template<sint8 change_it (sint8, sint8)>
320			static void
321	root	1.48	apply_light (player pl, int dx, int dy, int light, const sint8 atten_table)
322	root	1.39	{
323	root	1.41	// min or max the circular area around basex, basey
324			dx += LOS_X0;
325			dy += LOS_Y0;
326
327	root	1.48	int hx = pl->ns->mapx / 2;
328			int hy = pl->ns->mapy / 2;
329	root	1.41
330			int ax0 = max (LOS_X0 - hx, dx - light);
331			int ay0 = max (LOS_Y0 - hy, dy - light);
332			int ax1 = min (dx + light, LOS_X0 + hx);
333			int ay1 = min (dy + light, LOS_Y0 + hy);
334	root	1.39
335			for (int ax = ax0; ax <= ax1; ax++)
336			for (int ay = ay0; ay <= ay1; ay++)
337	root	1.41	pl->los[ax][ay] =
338	root	1.44	change_it (pl->los[ax][ay], atten_table [idistance (ax - dx, ay - dy)]);
339	root	1.39	}
340
341			/* add light, by finding all (non-null) nearby light sources, then
342			* mark those squares specially.
343			*/
344	root	1.4	static void
345	root	1.48	apply_lights (player *pl)
346	root	1.4	{
347	root	1.48	object *op = pl->observe;
348			int darklevel = op->map->darklevel ();
349	root	1.4
350	root	1.48	int half_x = pl->ns->mapx / 2;
351			int half_y = pl->ns->mapy / 2;
352	root	1.32
353			int pass2 = 0; // negative lights have an extra pass
354
355	root	1.52	maprect *rects = pl->observe->map->split_to_tiles (
356			pl->observe->x - half_x - MAX_LIGHT_RADIUS,
357			pl->observe->y - half_y - MAX_LIGHT_RADIUS,
358			pl->observe->x + half_x + MAX_LIGHT_RADIUS + 1,
359			pl->observe->y + half_y + MAX_LIGHT_RADIUS + 1
360			);
361
362	root	1.57	/* If the player can see in the dark, increase light/vision radius */
363			int bonus = op->flag [FLAG_SEE_IN_DARK] ? SEE_IN_DARK_RADIUS : 0;
364
365	root	1.48	if (!darklevel)
366	root	1.39	pass2 = 1;
367			else
368			{
369			/* first, make everything totally dark */
370	root	1.41	for (int dx = -half_x; dx <= half_x; dx++)
371			for (int dy = -half_x; dy <= half_y; dy++)
372	root	1.49	max_it (pl->los[dx + LOS_X0][dy + LOS_Y0], LOS_MAX);
373	root	1.39
374			/*
375			* Only process the area of interest.
376	root	1.41	* the basex, basey values represent the position in the op->contr->los
377			* array. Its easier to just increment them here (and start with the right
378	root	1.39	* value) than to recalculate them down below.
379			*/
380	root	1.52	for (maprect *r = rects; r->m; ++r)
381			rect_mapwalk (r, 0, 0)
382	root	1.39	{
383			mapspace &ms = m->at (nx, ny);
384			ms.update ();
385			sint8 light = ms.light;
386
387			if (expect_false (light))
388			if (light < 0)
389			pass2 = 1;
390			else
391	root	1.57	{
392			light = clamp (light + bonus, 0, MAX_LIGHT_RADIUS);
393			apply_light<los_brighten> (pl, dx - pl->observe->x, dy - pl->observe->y, light, light_atten [light + MAX_LIGHT_RADIUS]);
394			}
395	root	1.39	}
396
397	root	1.57	/* grant some vision to the player, based on outside, outdoor, and darklevel */
398	root	1.32	{
399	root	1.57	int light;
400	root	1.39
401	root	1.57	if (!op->map->outdoor) // not outdoor, darkness becomes light radius
402	root	1.58	light = MAX_DARKNESS - op->map->darkness;
403	root	1.57	else if (op->map->darkness > 0) // outdoor and darkness > 0 => use darkness as max radius
404			light = lerp_rd (maptile::outdoor_darkness + 0, 0, MAX_DARKNESS, MAX_DARKNESS - op->map->darkness, 0);
405			else // outdoor and darkness <= 0 => start wide and decrease quickly
406			light = lerp (maptile::outdoor_darkness + op->map->darkness, 0, MAX_DARKNESS, MAX_VISION, 2);
407
408	root	1.59	light = clamp (light + bonus, 0, MAX_VISION);
409	root	1.51
410	root	1.48	apply_light<los_brighten> (pl, 0, 0, light, vision_atten [light]);
411	root	1.32	}
412	root	1.39	}
413	root	1.4
414	root	1.38	// possibly do 2nd pass for rare negative glow radii
415	root	1.39	// for effect, those are always considered to be stronger than anything else
416			// but they can't darken a place completely
417			if (pass2)
418	root	1.52	for (maprect *r = rects; r->m; ++r)
419			rect_mapwalk (r, 0, 0)
420			{
421			mapspace &ms = m->at (nx, ny);
422			ms.update ();
423			sint8 light = ms.light;
424
425			if (expect_false (light < 0))
426	root	1.57	{
427			light = clamp (light - bonus, 0, MAX_DARKNESS);
428			apply_light<los_darken> (pl, dx - pl->observe->x, dy - pl->observe->y, -light, light_atten [light + MAX_LIGHT_RADIUS]);
429			}
430	root	1.52	}
431	elmex	1.1	}
432
433	root	1.31	/* blinded_sight() - sets all viewable squares to blocked except
434	elmex	1.1	* for the one the central one that the player occupies. A little
435			* odd that you can see yourself (and what your standing on), but
436			* really need for any reasonable game play.
437			*/
438	root	1.4	static void
439	root	1.48	blinded_sight (player *pl)
440	root	1.4	{
441	root	1.48	pl->los[LOS_X0][LOS_Y0] = 1;
442	elmex	1.1	}
443
444			/*
445			* update_los() recalculates the array which specifies what is
446			* visible for the given player-object.
447			*/
448	root	1.4	void
449	root	1.48	player::update_los ()
450	root	1.4	{
451	root	1.48	if (ob->flag [FLAG_REMOVED])//D really needed?
452	root	1.4	return;
453	elmex	1.1
454	root	1.48	if (ob->flag [FLAG_WIZLOOK])
455	root	1.49	clear_los (0);
456	root	1.48	else if (observe->flag [FLAG_BLIND]) /* player is blind */
457	root	1.49	{
458			clear_los ();
459			blinded_sight (this);
460			}
461	root	1.4	else
462	root	1.41	{
463	root	1.49	clear_los ();
464	root	1.48	calculate_los (this);
465			apply_lights (this);
466	root	1.41	}
467	root	1.4
468	root	1.48	if (observe->flag [FLAG_XRAYS])
469	root	1.41	for (int dx = -2; dx <= 2; dx++)
470			for (int dy = -2; dy <= 2; dy++)
471	root	1.49	min_it (los[dx + LOS_X0][dy + LOS_Y0], 1);
472	elmex	1.1	}
473
474			/* update all_map_los is like update_all_los below,
475			* but updates everyone on the map, no matter where they
476	root	1.12	* are. This generally should not be used, as a per
477	elmex	1.1	* specific map change doesn't make much sense when tiling
478			* is considered (lowering darkness would certainly be a
479			* strange effect if done on a tile map, as it makes
480			* the distinction between maps much more obvious to the
481			* players, which is should not be.
482			* Currently, this function is called from the
483			* change_map_light function
484			*/
485	root	1.4	void
486	root	1.6	update_all_map_los (maptile *map)
487	root	1.4	{
488	root	1.46	for_all_players_on_map (pl, map)
489			pl->do_los = 1;
490	elmex	1.1	}
491
492			/*
493			* This function makes sure that update_los() will be called for all
494			* players on the given map within the next frame.
495			* It is triggered by removal or inserting of objects which blocks
496			* the sight in the map.
497			* Modified by MSW 2001-07-12 to take a coordinate of the changed
498			* position, and to also take map tiling into account. This change
499			* means that just being on the same map is not sufficient - the
500			* space that changes must be withing your viewable area.
501			*
502			* map is the map that changed, x and y are the coordinates.
503			*/
504	root	1.4	void
505	root	1.6	update_all_los (const maptile *map, int x, int y)
506	root	1.4	{
507	root	1.46	map->at (x, y).invalidate ();
508
509	root	1.11	for_all_players (pl)
510	root	1.4	{
511			/* Player should not have a null map, but do this
512			* check as a safety
513			*/
514	root	1.12	if (!pl->ob \|\| !pl->ob->map \|\| !pl->ns)
515	root	1.4	continue;
516
517	root	1.61	rv_vector rv;
518
519			get_rangevector_from_mapcoord (map, x, y, pl->ob, &rv);
520
521			if ((abs (rv.distance_x) <= pl->ns->mapx / 2) && (abs (rv.distance_y) <= pl->ns->mapy / 2))
522			pl->do_los = 1;
523	elmex	1.1	}
524			}
525
526	root	1.48	static const int season_darkness[5][HOURS_PER_DAY] = {
527			/0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 1 2 3 4 5 6 7 8 9 10 11 12 13 /
528			{ 5, 5, 4, 4, 4, 4, 4, 3, 3, 3, 3, 2, 2, 1, 1, 0, 0, 0, 0, 1, 2, 2, 2, 3, 3, 4, 4, 5 },
529			{ 5, 5, 4, 4, 4, 4, 3, 3, 3, 2, 2, 1, 1, 0, 0, 0, 0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4 },
530			{ 5, 4, 4, 4, 4, 3, 3, 2, 2, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 2, 2, 3, 4, 4 },
531			{ 4, 4, 4, 4, 3, 3, 2, 2, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 2, 2, 3, 4 },
532			{ 5, 5, 4, 4, 4, 3, 3, 3, 2, 2, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4 }
533	root	1.47	};
534
535	root	1.48	/*
536			* Tell players the time and compute the darkness level for all maps in the game.
537			* MUST be called exactly once per hour.
538			*/
539	root	1.47	void
540	root	1.48	maptile::adjust_daylight ()
541	root	1.47	{
542			timeofday_t tod;
543
544			get_tod (&tod);
545
546	root	1.48	// log the time to log-1 every hour, and to chat every day
547			{
548			char todbuf[512];
549	root	1.47
550	root	1.48	format_tod (todbuf, sizeof (todbuf), &tod);
551	root	1.47
552	root	1.48	for_all_players (pl)
553			pl->ns->send_msg (NDI_GREY, tod.hour == 15 ? CHAT_CHANNEL : LOG_CHANNEL, todbuf);
554			}
555	root	1.47
556			/* If the light level isn't changing, no reason to do all
557			* the work below.
558			*/
559	root	1.48	sint8 new_darkness = season_darkness[tod.season][tod.hour];
560
561			if (new_darkness == maptile::outdoor_darkness)
562	root	1.47	return;
563
564	root	1.48	new_draw_info (NDI_GREY \| NDI_UNIQUE \| NDI_ALL, 1, 0,
565			new_darkness > maptile::outdoor_darkness
566			? "It becomes darker."
567			: "It becomes brighter.");
568	root	1.47
569	root	1.48	maptile::outdoor_darkness = new_darkness;
570	root	1.47
571	root	1.48	// we simply update the los for all players, which is unnecessarily
572			// costly, but should do for the moment.
573			for_all_players (pl)
574			pl->do_los = 1;
575	root	1.47	}
576
577	elmex	1.1	/*
578			* make_sure_seen: The object is supposed to be visible through walls, thus
579			* check if any players are nearby, and edit their LOS array.
580			*/
581	root	1.4	void
582			make_sure_seen (const object *op)
583			{
584	root	1.11	for_all_players (pl)
585	root	1.4	if (pl->ob->map == op->map &&
586	root	1.10	pl->ob->y - pl->ns->mapy / 2 <= op->y &&
587			pl->ob->y + pl->ns->mapy / 2 >= op->y && pl->ob->x - pl->ns->mapx / 2 <= op->x && pl->ob->x + pl->ns->mapx / 2 >= op->x)
588	root	1.49	pl->los[op->x - pl->ob->x + LOS_X0][op->y - pl->ob->y + LOS_Y0] = 0;
589	elmex	1.1	}
590
591			/*
592			* make_sure_not_seen: The object which is supposed to be visible through
593			* walls has just been removed from the map, so update the los of any
594			* players within its range
595			*/
596	root	1.4	void
597			make_sure_not_seen (const object *op)
598			{
599	root	1.11	for_all_players (pl)
600	root	1.4	if (pl->ob->map == op->map &&
601	root	1.10	pl->ob->y - pl->ns->mapy / 2 <= op->y &&
602			pl->ob->y + pl->ns->mapy / 2 >= op->y && pl->ob->x - pl->ns->mapx / 2 <= op->x && pl->ob->x + pl->ns->mapx / 2 >= op->x)
603	root	1.4	pl->do_los = 1;
604	elmex	1.1	}
605	root	1.52