+++ /dev/null
-/*
- * Empire - A multi-player, client/server Internet based war game.
- * Copyright (C) 1986-2010, Dave Pare, Jeff Bailey, Thomas Ruschak,
- * Ken Stevens, Steve McClure
- *
- * 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
- *
- * ---
- *
- * See files README, COPYING and CREDITS in the root of the source
- * tree for related information and legal notices. It is expected
- * that future projects/authors will amend these files as needed.
- *
- * ---
- *
- * as_cache.c: Routines used to create/delete caches of A* paths.
- *
- * Known contributors to this file:
- * Steve McClure, 1998
- */
-
-#include <config.h>
-
-#include <stdlib.h>
-#include <string.h>
-#include "as.h"
-#include "optlist.h"
-
-/* The way this works is interesting. :) */
-/* We keep a pointer to a list of pointers. The index into this list
- * is the y coordinate of the from sector. This member points to a list
- * of from sectors on that y coordinate. So, we march that list checking
- * the x value to find the from x,y we want. */
-/* Once we find the from x,y, that node has the same type of pointer to
- * a list of pointers. The index into this list is the y coordinate of
- * the to sector. This member points to a list of to sectors on that y
- * coordinate. So, we march that list checking the x value to find the
- * to x,y we want. */
-/* These lists are dynamically created since the world is dynamically sized. */
-/* See, I told you it was interesting. :) */
-
-static struct as_frompath **fromhead = (struct as_frompath **)0;
-
-/* Note that we only want to cache during updates. Other times, it
- * probably doesn't make much sense, but can be done. */
-
-static int as_cachepath_on = 0; /* Default to off */
-
-void
-as_enable_cachepath(void)
-{
- as_cachepath_on = 1;
-}
-
-void
-as_disable_cachepath(void)
-{
- as_cachepath_on = 0;
-}
-
-/* Note we want these to be as fast as possible */
-
-void
-as_add_cachepath(struct as_data *adp)
-{
- struct as_frompath *from;
- struct as_topath *to = (struct as_topath *)0;
- struct as_node *np;
-
- /* Don't do anything if we aren't cacheing these */
- if (as_cachepath_on == 0)
- return;
-
- /* Note we will only allocate this once. Afterwards, we just keep
- * zeroing it since it's rather small and we don't need to re-allocate
- * each time. */
- if (fromhead == NULL) {
- fromhead = calloc(1, sizeof(struct as_frompath *) * WORLD_Y);
- if (fromhead == NULL)
- return;
- }
-
- np = adp->head->np;
- for (from = fromhead[adp->from.y]; from; from = from->next)
- if (from->x == adp->from.x)
- break;
- if (from) {
- for (to = from->tolist[np->c.y]; to; to = to->next) {
- if (to->x == np->c.x) {
- /* It is already here! Don't bother adding it again */
- return;
- }
- }
- } else {
- /* We must make a new one of these */
- from = malloc(sizeof(struct as_frompath));
- if (from == NULL)
- return;
- /* And set some stuff */
- from->x = adp->from.x;
- /* Here we malloc a whole bunch of tolist pointers. */
- from->tolist = calloc(1, sizeof(struct as_topath *) * WORLD_Y);
- /* Now, add from to the global list */
- from->next = fromhead[adp->from.y];
- fromhead[adp->from.y] = from;
- }
- if (!to) {
- /* We must make a new one */
- to = malloc(sizeof(struct as_topath));
- /* We can't, sorry */
- if (to == NULL)
- return;
- /* Now set some stuff */
- to->x = np->c.x;
- /* Now add it to the list we are in */
- to->next = from->tolist[np->c.y];
- from->tolist[np->c.y] = to;
- }
- /* Now, make the path */
- as_makepath(adp);
- /* Now, take the path */
- to->path = adp->path;
- /* And clear the path in the adp */
- adp->path = NULL;
-}
-
-void
-as_clear_cachepath(void)
-{
- struct as_frompath *from, *from2;
- struct as_topath *to, *to2;
- int i, j;
-
- /* Cache not used yet :) */
- if (fromhead == NULL)
- return;
-
- for (j = 0; j < WORLD_Y; j++) {
- for (from = fromhead[j]; from; from = from2) {
- for (i = 0; i < WORLD_Y; i++) {
- for (to = from->tolist[i]; to; to = to2) {
- to2 = to->next;
- /* Free this path */
- as_free_path(to->path);
- /* Free this node */
- free(to);
- }
- }
- /* Now, free the list of lists */
- free(from->tolist);
- /* Save the next pointer */
- from2 = from->next;
- /* now, free this from node */
- free(from);
- }
- }
- /* Note we don't free the fromhead here, we just zero it. That way,
- we can use it next time without mallocing int */
- memset(fromhead, 0, (sizeof(struct as_frompath *) * WORLD_Y));
-}
-
-struct as_path *
-as_find_cachepath(coord fx, coord fy, coord tx, coord ty)
-{
- struct as_frompath *from;
- struct as_topath *to;
-
- /* Is the cache on? if not, return NULL */
- if (as_cachepath_on == 0)
- return NULL;
-
- /* Do we have any cached? */
- if (fromhead == NULL)
- return NULL;
-
- /* Yes! */
- for (from = fromhead[fy]; from; from = from->next) {
- if (from->x == fx) {
- for (to = from->tolist[ty]; to; to = to->next) {
- if (to->x == tx)
- return to->path;
- }
- }
- }
- return NULL;
-}
projects / empserver / blobdiff