/* CrossFire, A Multiplayer game for X-windows Copyright (C) 2002 Mark Wedel & Crossfire Development Team Copyright (C) 1992 Frank Tore Johansen 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., 675 Mass Ave, Cambridge, MA 02139, USA. The authors can be reached via e-mail at */ /* Nov 95 - inserted USE_LIGHTING code stuff in here - b.t. */ #include #include #include /* Distance must be less than this for the object to be blocked. * An object is 1.0 wide, so if set to 0.5, it means the object * that blocks half the view (0.0 is complete block) will * block view in our tables. * .4 or less lets you see through walls. .5 is about right. */ #define SPACE_BLOCK 0.5 typedef struct blstr { int x[4], y[4]; int index; } blocks; blocks block[MAP_CLIENT_X][MAP_CLIENT_Y]; static void expand_lighted_sight (object *op); /* * Used to initialise the array used by the LOS routines. * What this sets if that x,y blocks the view of bx,by * This then sets up a relation - for example, something * at 5,4 blocks view at 5,3 which blocks view at 5,2 * etc. So when we check 5,4 and find it block, we have * the data to know that 5,3 and 5,2 and 5,1 should also * be blocked. */ static void set_block (int x, int y, int bx, int by) { int index = block[x][y].index, i; /* Due to flipping, we may get duplicates - better safe than sorry. */ for (i = 0; i < index; i++) { if (block[x][y].x[i] == bx && block[x][y].y[i] == by) return; } block[x][y].x[index] = bx; block[x][y].y[index] = by; block[x][y].index++; #ifdef LOS_DEBUG LOG (llevDebug, "setblock: added %d %d -> %d %d (%d)\n", x, y, bx, by, block[x][y].index); #endif } /* * initialises the array used by the LOS routines. */ /* since we are only doing the upper left quadrant, only * these spaces could possibly get blocked, since these * are the only ones further out that are still possibly in the * sightline. */ void init_block (void) { int x, y, dx, dy, i; static int block_x[3] = { -1, -1, 0 }, block_y[3] = { -1, 0, -1}; for (x = 0; x < MAP_CLIENT_X; x++) for (y = 0; y < MAP_CLIENT_Y; y++) { block[x][y].index = 0; } /* The table should be symmetric, so only do the upper left * quadrant - makes the processing easier. */ for (x = 1; x <= MAP_CLIENT_X / 2; x++) { for (y = 1; y <= MAP_CLIENT_Y / 2; y++) { for (i = 0; i < 3; i++) { dx = x + block_x[i]; dy = y + block_y[i]; /* center space never blocks */ if (x == MAP_CLIENT_X / 2 && y == MAP_CLIENT_Y / 2) continue; /* If its a straight line, its blocked */ if ((dx == x && x == MAP_CLIENT_X / 2) || (dy == y && y == MAP_CLIENT_Y / 2)) { /* For simplicity, we mirror the coordinates to block the other * quadrants. */ set_block (x, y, dx, dy); if (x == MAP_CLIENT_X / 2) { set_block (x, MAP_CLIENT_Y - y - 1, dx, MAP_CLIENT_Y - dy - 1); } else if (y == MAP_CLIENT_Y / 2) { set_block (MAP_CLIENT_X - x - 1, y, MAP_CLIENT_X - dx - 1, dy); } } else { float d1, r, s, l; /* We use the algorihm that found out how close the point * (x,y) is to the line from dx,dy to the center of the viewable * area. l is the distance from x,y to the line. * r is more a curiosity - it lets us know what direction (left/right) * the line is off */ d1 = (float) (pow (MAP_CLIENT_X / 2 - dx, 2) + pow (MAP_CLIENT_Y / 2 - dy, 2)); r = (float) ((dy - y) * (dy - MAP_CLIENT_Y / 2) - (dx - x) * (MAP_CLIENT_X / 2 - dx)) / d1; s = (float) ((dy - y) * (MAP_CLIENT_X / 2 - dx) - (dx - x) * (MAP_CLIENT_Y / 2 - dy)) / d1; l = FABS (sqrt (d1) * s); if (l <= SPACE_BLOCK) { /* For simplicity, we mirror the coordinates to block the other * quadrants. */ set_block (x, y, dx, dy); set_block (MAP_CLIENT_X - x - 1, y, MAP_CLIENT_X - dx - 1, dy); set_block (x, MAP_CLIENT_Y - y - 1, dx, MAP_CLIENT_Y - dy - 1); set_block (MAP_CLIENT_X - x - 1, MAP_CLIENT_Y - y - 1, MAP_CLIENT_X - dx - 1, MAP_CLIENT_Y - dy - 1); } } } } } } /* * Used to initialise the array used by the LOS routines. * x,y are indexes into the blocked[][] array. * This recursively sets the blocked line of sight view. * From the blocked[][] array, we know for example * that if some particular space is blocked, it blocks * the view of the spaces 'behind' it, and those blocked * spaces behind it may block other spaces, etc. * In this way, the chain of visibility is set. */ static void set_wall (object *op, int x, int y) { int i; for (i = 0; i < block[x][y].index; i++) { int dx = block[x][y].x[i], dy = block[x][y].y[i], ax, ay; /* ax, ay are the values as adjusted to be in the * socket look structure. */ ax = dx - (MAP_CLIENT_X - op->contr->socket.mapx) / 2; ay = dy - (MAP_CLIENT_Y - op->contr->socket.mapy) / 2; if (ax < 0 || ax >= op->contr->socket.mapx || ay < 0 || ay >= op->contr->socket.mapy) continue; #if 0 LOG (llevDebug, "blocked %d %d -> %d %d\n", dx, dy, ax, ay); #endif /* we need to adjust to the fact that the socket * code wants the los to start from the 0,0 * and not be relative to middle of los array. */ op->contr->blocked_los[ax][ay] = 100; set_wall (op, dx, dy); } } /* * Used to initialise the array used by the LOS routines. * op is the object, x and y values based on MAP_CLIENT_X and Y. * this is because they index the blocked[][] arrays. */ static void check_wall (object *op, int x, int y) { int ax, ay; if (!block[x][y].index) return; /* ax, ay are coordinates as indexed into the look window */ ax = x - (MAP_CLIENT_X - op->contr->socket.mapx) / 2; ay = y - (MAP_CLIENT_Y - op->contr->socket.mapy) / 2; /* If the converted coordinates are outside the viewable * area for the client, return now. */ if (ax < 0 || ay < 0 || ax >= op->contr->socket.mapx || ay >= op->contr->socket.mapy) return; #if 0 LOG (llevDebug, "check_wall, ax,ay=%d, %d x,y = %d, %d blocksview = %d, %d\n", ax, ay, x, y, op->x + x - MAP_CLIENT_X / 2, op->y + y - MAP_CLIENT_Y / 2); #endif /* If this space is already blocked, prune the processing - presumably * whatever has set this space to be blocked has done the work and already * done the dependency chain. */ if (op->contr->blocked_los[ax][ay] == 100) return; if (get_map_flags (op->map, NULL, op->x + x - MAP_CLIENT_X / 2, op->y + y - MAP_CLIENT_Y / 2, NULL, NULL) & (P_BLOCKSVIEW | P_OUT_OF_MAP)) set_wall (op, x, y); } /* * Clears/initialises the los-array associated to the player * controlling the object. */ void clear_los (object *op) { /* This is safer than using the socket->mapx, mapy because * we index the blocked_los as a 2 way array, so clearing * the first z spaces may not not cover the spaces we are * actually going to use */ (void) memset ((void *) op->contr->blocked_los, 0, MAP_CLIENT_X * MAP_CLIENT_Y); } /* * expand_sight goes through the array of what the given player is * able to see, and expands the visible area a bit, so the player will, * to a certain degree, be able to see into corners. * This is somewhat suboptimal, would be better to improve the formula. */ static void expand_sight (object *op) { int i, x, y, dx, dy; for (x = 1; x < op->contr->socket.mapx - 1; x++) /* loop over inner squares */ for (y = 1; y < op->contr->socket.mapy - 1; y++) { if (!op->contr->blocked_los[x][y] && !(get_map_flags (op->map, NULL, op->x - op->contr->socket.mapx / 2 + x, op->y - op->contr->socket.mapy / 2 + y, NULL, NULL) & (P_BLOCKSVIEW | P_OUT_OF_MAP))) { for (i = 1; i <= 8; i += 1) { /* mark all directions */ dx = x + freearr_x[i]; dy = y + freearr_y[i]; if (op->contr->blocked_los[dx][dy] > 0) /* for any square blocked */ op->contr->blocked_los[dx][dy] = -1; } } } if (MAP_DARKNESS (op->map) > 0) /* player is on a dark map */ expand_lighted_sight (op); /* clear mark squares */ for (x = 0; x < op->contr->socket.mapx; x++) for (y = 0; y < op->contr->socket.mapy; y++) if (op->contr->blocked_los[x][y] < 0) op->contr->blocked_los[x][y] = 0; } /* returns true if op carries one or more lights * This is a trivial function now days, but it used to * be a bit longer. Probably better for callers to just * check the op->glow_radius instead of calling this. */ int has_carried_lights (const object *op) { /* op may glow! */ if (op->glow_radius > 0) return 1; return 0; } static void expand_lighted_sight (object *op) { int x, y, darklevel, ax, ay, basex, basey, mflags, light, x1, y1; mapstruct *m = op->map; sint16 nx, ny; darklevel = MAP_DARKNESS (m); /* If the player can see in the dark, lower the darklevel for him */ if (QUERY_FLAG (op, FLAG_SEE_IN_DARK)) darklevel -= 2; /* add light, by finding all (non-null) nearby light sources, then * mark those squares specially. If the darklevel<1, there is no * reason to do this, so we skip this function */ if (darklevel < 1) return; /* Do a sanity check. If not valid, some code below may do odd * things. */ if (darklevel > MAX_DARKNESS) { LOG (llevError, "Map darkness for %s on %s is too high (%d)\n", &op->name, op->map->path, darklevel); darklevel = MAX_DARKNESS; } /* First, limit player furthest (unlighted) vision */ for (x = 0; x < op->contr->socket.mapx; x++) for (y = 0; y < op->contr->socket.mapy; y++) if (op->contr->blocked_los[x][y] != 100) op->contr->blocked_los[x][y] = MAX_LIGHT_RADII; /* the spaces[] darkness value contains the information we need. * Only process the area of interest. * the basex, basey values represent the position in the op->contr->blocked_los * array. Its easier to just increment them here (and start with the right * value) than to recalculate them down below. */ for (x = (op->x - op->contr->socket.mapx / 2 - MAX_LIGHT_RADII), basex = -MAX_LIGHT_RADII; x <= (op->x + op->contr->socket.mapx / 2 + MAX_LIGHT_RADII); x++, basex++) { for (y = (op->y - op->contr->socket.mapy / 2 - MAX_LIGHT_RADII), basey = -MAX_LIGHT_RADII; y <= (op->y + op->contr->socket.mapy / 2 + MAX_LIGHT_RADII); y++, basey++) { m = op->map; nx = x; ny = y; mflags = get_map_flags (m, &m, nx, ny, &nx, &ny); if (mflags & P_OUT_OF_MAP) continue; /* This space is providing light, so we need to brighten up the * spaces around here. */ light = GET_MAP_LIGHT (m, nx, ny); if (light != 0) { #if 0 LOG (llevDebug, "expand_lighted_sight: Found light at x=%d, y=%d, basex=%d, basey=%d\n", x, y, basex, basey); #endif for (ax = basex - light; ax <= basex + light; ax++) { if (ax < 0 || ax >= op->contr->socket.mapx) continue; for (ay = basey - light; ay <= basey + light; ay++) { if (ay < 0 || ay >= op->contr->socket.mapy) continue; /* If the space is fully blocked, do nothing. Otherwise, we * brighten the space. The further the light is away from the * source (basex-x), the less effect it has. Though light used * to dim in a square manner, it now dims in a circular manner * using the the pythagorean theorem. glow_radius still * represents the radius */ if (op->contr->blocked_los[ax][ay] != 100) { x1 = abs (basex - ax) * abs (basex - ax); y1 = abs (basey - ay) * abs (basey - ay); if (light > 0) op->contr->blocked_los[ax][ay] -= MAX ((light - isqrt (x1 + y1)), 0); if (light < 0) op->contr->blocked_los[ax][ay] -= MIN ((light + isqrt (x1 + y1)), 0); } } /* for ay */ } /* for ax */ } /* if this space is providing light */ } /* for y */ } /* for x */ /* Outdoor should never really be completely pitch black dark like * a dungeon, so let the player at least see a little around themselves */ if (op->map->outdoor && darklevel > (MAX_DARKNESS - 3)) { if (op->contr->blocked_los[op->contr->socket.mapx / 2][op->contr->socket.mapy / 2] > (MAX_DARKNESS - 3)) op->contr->blocked_los[op->contr->socket.mapx / 2][op->contr->socket.mapy / 2] = MAX_DARKNESS - 3; for (x = -1; x <= 1; x++) for (y = -1; y <= 1; y++) { if (op->contr->blocked_los[x + op->contr->socket.mapx / 2][y + op->contr->socket.mapy / 2] > (MAX_DARKNESS - 2)) op->contr->blocked_los[x + op->contr->socket.mapx / 2][y + op->contr->socket.mapy / 2] = MAX_DARKNESS - 2; } } /* grant some vision to the player, based on the darklevel */ for (x = darklevel - MAX_DARKNESS; x < MAX_DARKNESS + 1 - darklevel; x++) for (y = darklevel - MAX_DARKNESS; y < MAX_DARKNESS + 1 - darklevel; y++) if (!(op->contr->blocked_los[x + op->contr->socket.mapx / 2][y + op->contr->socket.mapy / 2] == 100)) op->contr->blocked_los[x + op->contr->socket.mapx / 2][y + op->contr->socket.mapy / 2] -= MAX (0, 6 - darklevel - MAX (abs (x), abs (y))); } /* blinded_sight() - sets all veiwable 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 (object *op) { int x, y; for (x = 0; x < op->contr->socket.mapx; x++) for (y = 0; y < op->contr->socket.mapy; y++) op->contr->blocked_los[x][y] = 100; op->contr->blocked_los[op->contr->socket.mapx / 2][op->contr->socket.mapy / 2] = 0; } /* * update_los() recalculates the array which specifies what is * visible for the given player-object. */ void update_los (object *op) { int dx = op->contr->socket.mapx / 2, dy = op->contr->socket.mapy / 2, x, y; if (QUERY_FLAG (op, FLAG_REMOVED)) return; clear_los (op); if (QUERY_FLAG (op, FLAG_WIZ) /* ||XRAYS(op) */ ) return; /* For larger maps, this is more efficient than the old way which * used the chaining of the block array. Since many space views could * be blocked by different spaces in front, this mean that a lot of spaces * could be examined multile times, as each path would be looked at. */ for (x = (MAP_CLIENT_X - op->contr->socket.mapx) / 2 - 1; x < (MAP_CLIENT_X + op->contr->socket.mapx) / 2 + 1; x++) for (y = (MAP_CLIENT_Y - op->contr->socket.mapy) / 2 - 1; y < (MAP_CLIENT_Y + op->contr->socket.mapy) / 2 + 1; y++) check_wall (op, x, y); /* do the los of the player. 3 (potential) cases */ if (QUERY_FLAG (op, FLAG_BLIND)) /* player is blind */ blinded_sight (op); else expand_sight (op); if (QUERY_FLAG (op, FLAG_XRAYS)) { int x, y; for (x = -2; x <= 2; x++) for (y = -2; y <= 2; y++) op->contr->blocked_los[dx + x][dy + y] = 0; } } /* 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 (mapstruct *map) { player *pl; for (pl = first_player; pl != NULL; pl = pl->next) { if (pl->ob->map == 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 mapstruct *map, int x, int y) { player *pl; for (pl = first_player; pl != NULL; pl = pl->next) { /* Player should not have a null map, but do this * check as a safety */ if (!pl->ob->map) continue; /* Same map is simple case - see if pl is close enough. * Note in all cases, we did the check for same map first, * and then see if the player is close enough and update * los if that is the case. If the player is on the * corresponding map, but not close enough, then the * player can't be on another map that may be closer, * so by setting it up this way, we trim processing * some. */ if (pl->ob->map == map) { if ((abs (pl->ob->x - x) <= pl->socket.mapx / 2) && (abs (pl->ob->y - y) <= pl->socket.mapy / 2)) pl->do_los = 1; } /* Now we check to see if player is on adjacent * maps to the one that changed and also within * view. The tile_maps[] could be null, but in that * case it should never match the pl->ob->map, so * we want ever try to dereference any of the data in it. */ /* The logic for 0 and 3 is to see how far the player is * from the edge of the map (height/width) - pl->ob->(x,y) * and to add current position on this map - that gives a * distance. * For 1 and 2, we check to see how far the given * coordinate (x,y) is from the corresponding edge, * and then add the players location, which gives * a distance. */ else if (pl->ob->map == map->tile_map[0]) { if ((abs (pl->ob->x - x) <= pl->socket.mapx / 2) && (abs (y + MAP_HEIGHT (map->tile_map[0]) - pl->ob->y) <= pl->socket.mapy / 2)) pl->do_los = 1; } else if (pl->ob->map == map->tile_map[2]) { if ((abs (pl->ob->x - x) <= pl->socket.mapx / 2) && (abs (pl->ob->y + MAP_HEIGHT (map) - y) <= pl->socket.mapy / 2)) pl->do_los = 1; } else if (pl->ob->map == map->tile_map[1]) { if ((abs (pl->ob->x + MAP_WIDTH (map) - x) <= pl->socket.mapx / 2) && (abs (pl->ob->y - y) <= pl->socket.mapy / 2)) pl->do_los = 1; } else if (pl->ob->map == map->tile_map[3]) { if ((abs (x + MAP_WIDTH (map->tile_map[3]) - pl->ob->x) <= pl->socket.mapx / 2) && (abs (pl->ob->y - y) <= pl->socket.mapy / 2)) pl->do_los = 1; } } } /* * Debug-routine which dumps the array which specifies the visible * area of a player. Triggered by the z key in DM mode. */ void print_los (object *op) { int x, y; char buf[50], buf2[10]; strcpy (buf, " "); for (x = 0; x < op->contr->socket.mapx; x++) { sprintf (buf2, "%2d", x); strcat (buf, buf2); } new_draw_info (NDI_UNIQUE, 0, op, buf); for (y = 0; y < op->contr->socket.mapy; y++) { sprintf (buf, "%2d:", y); for (x = 0; x < op->contr->socket.mapx; x++) { sprintf (buf2, " %1d", op->contr->blocked_los[x][y]); strcat (buf, buf2); } new_draw_info (NDI_UNIQUE, 0, op, buf); } } /* * 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) { player *pl; for (pl = first_player; pl; pl = pl->next) if (pl->ob->map == op->map && pl->ob->y - pl->socket.mapy / 2 <= op->y && pl->ob->y + pl->socket.mapy / 2 >= op->y && pl->ob->x - pl->socket.mapx / 2 <= op->x && pl->ob->x + pl->socket.mapx / 2 >= op->x) pl->blocked_los[pl->socket.mapx / 2 + op->x - pl->ob->x][pl->socket.mapy / 2 + op->y - pl->ob->y] = 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) { player *pl; for (pl = first_player; pl; pl = pl->next) if (pl->ob->map == op->map && pl->ob->y - pl->socket.mapy / 2 <= op->y && pl->ob->y + pl->socket.mapy / 2 >= op->y && pl->ob->x - pl->socket.mapx / 2 <= op->x && pl->ob->x + pl->socket.mapx / 2 >= op->x) pl->do_los = 1; }