--- deliantra/server/common/map.C 2007/09/06 06:53:05 1.125
+++ deliantra/server/common/map.C 2009/11/06 13:03:34 1.168
@@ -1,35 +1,37 @@
/*
- * This file is part of Crossfire TRT, the Roguelike Realtime MORPG.
+ * This file is part of Deliantra, the Roguelike Realtime MMORPG.
*
- * Copyright (©) 2005,2006,2007 Marc Alexander Lehmann / Robin Redeker / the Crossfire TRT team
+ * Copyright (©) 2005,2006,2007,2008,2009 Marc Alexander Lehmann / Robin Redeker / the Deliantra team
* Copyright (©) 2001-2003,2007 Mark Wedel & Crossfire Development Team
* Copyright (©) 1992,2007 Frank Tore Johansen
*
- * Crossfire TRT 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.
+ * Deliantra is free software: you can redistribute it and/or modify it under
+ * the terms of the Affero 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 .
+ * You should have received a copy of the Affero GNU General Public License
+ * and the GNU General Public License along with this program. If not, see
+ * .
*
- * The authors can be reached via e-mail to
+ * The authors can be reached via e-mail to
*/
#include
#include "global.h"
-#include "funcpoint.h"
-
#include "loader.h"
-
#include "path.h"
+//+GPL
+
+sint8 maptile::outdoor_darkness;
+
/* This rolls up wall, blocks_magic, blocks_view, etc, all into
* one function that just returns a P_.. value (see map.h)
* it will also do map translation for tiled maps, returning
@@ -73,9 +75,6 @@
int
blocked_link (object *ob, maptile *m, int sx, int sy)
{
- object *tmp;
- int mflags, blocked;
-
/* Make sure the coordinates are valid - they should be, as caller should
* have already checked this.
*/
@@ -85,12 +84,10 @@
return 1;
}
- /* Save some cycles - instead of calling get_map_flags(), just get the value
- * directly.
- */
- mflags = m->at (sx, sy).flags ();
+ mapspace &ms = m->at (sx, sy);
- blocked = GET_MAP_MOVE_BLOCK (m, sx, sy);
+ int mflags = ms.flags ();
+ int blocked = ms.move_block;
/* If space is currently not blocked by anything, no need to
* go further. Not true for players - all sorts of special
@@ -99,7 +96,7 @@
if (ob->type != PLAYER && !(mflags & P_IS_ALIVE) && (blocked == 0))
return 0;
- /* if there isn't anytyhing alive on this space, and this space isn't
+ /* if there isn't anything alive on this space, and this space isn't
* otherwise blocked, we can return now. Only if there is a living
* creature do we need to investigate if it is part of this creature
* or another. Likewise, only if something is blocking us do we
@@ -116,63 +113,60 @@
* true. If we get through the entire stack, that must mean
* ob is blocking it, so return 0.
*/
- for (tmp = GET_MAP_OB (m, sx, sy); tmp; tmp = tmp->above)
+ for (object *tmp = ms.bot; tmp; tmp = tmp->above)
{
-
- /* This must be before the checks below. Code for inventory checkers. */
- if (tmp->type == CHECK_INV && OB_MOVE_BLOCK (ob, tmp))
+ if (OB_MOVE_BLOCK (ob, tmp))
{
- /* If last_sp is set, the player/monster needs an object,
- * so we check for it. If they don't have it, they can't
- * pass through this space.
- */
- if (tmp->last_sp)
+ if (INVOKE_OBJECT (BLOCKED_MOVE, tmp, ob))
+ if (RESULT_INT (0))
+ return 1;
+ else
+ continue;
+
+ if (tmp->type == CHECK_INV)
{
- if (check_inv_recursive (ob, tmp) == NULL)
+ bool have = check_inv_recursive (ob, tmp);
+
+ // last_sp set means we block if we don't have.
+ if (logical_xor (have, tmp->last_sp))
return 1;
- else
- continue;
}
- else
+ else if (tmp->type == T_MATCH)
{
- /* In this case, the player must not have the object -
- * if they do, they can't pass through.
- */
- if (check_inv_recursive (ob, tmp) != NULL) /* player has object */
+ // T_MATCH allows "entrance" iff the match is true
+ // == blocks if the match fails
+
+ // we could have used an INVOKE_OBJECT, but decided against it, as we
+ // assume that T_MATCH is relatively common.
+ if (!match (tmp->slaying, ob, tmp, ob))
return 1;
- else
- continue;
}
- } /* if check_inv */
- else
- {
- /* Broke apart a big nasty if into several here to make
- * this more readable. first check - if the space blocks
- * movement, can't move here.
- * second - if a monster, can't move there, unless it is a
- * hidden dm
- */
- if (OB_MOVE_BLOCK (ob, tmp))
- return 1;
+ else
+ return 1; // unconditional block
+
+ } else {
+ // space does not block the ob, directly, but
+ // anything alive that is not a door still
+ // blocks anything but wizards.
if (tmp->flag [FLAG_ALIVE]
&& tmp->head_ () != ob
&& tmp != ob
&& tmp->type != DOOR
- && !(tmp->flag [FLAG_WIZ] && tmp->contr->hidden))
+ && !tmp->flag [FLAG_WIZPASS])
return 1;
}
-
}
+
return 0;
}
/*
- * Returns true if the given object can't fit in the given spot.
- * This is meant for multi space objects - for single space objecs,
+ * Returns qthe blocking object if the given object can't fit in the given
+ * spot. This is meant for multi space objects - for single space objecs,
* just calling get_map_blocked and checking that against movement type
- * of object. This function goes through all the parts of the
- * multipart object and makes sure they can be inserted.
+ * of object. This function goes through all the parts of the multipart
+ * object and makes sure they can be inserted.
*
* While this doesn't call out of map, the get_map_flags does.
*
@@ -193,48 +187,33 @@
* code, we need to have actual object to check its move_type
* against the move_block values.
*/
-int
-ob_blocked (const object *ob, maptile *m, sint16 x, sint16 y)
+bool
+object::blocked (maptile *m, int x, int y) const
{
- archetype *tmp;
- int flag;
- maptile *m1;
- sint16 sx, sy;
-
- if (!ob)
+ for (archetype *tmp = arch; tmp; tmp = (archetype *)tmp->more)
{
- flag = get_map_flags (m, &m1, x, y, &sx, &sy);
- if (flag & P_OUT_OF_MAP)
- return P_OUT_OF_MAP;
-
- /* don't have object, so don't know what types would block */
- return m1->at (sx, sy).move_block;
- }
+ mapxy pos (m, x + tmp->x, y + tmp->y);
- for (tmp = ob->arch; tmp; tmp = (archetype *)tmp->more)
- {
- flag = get_map_flags (m, &m1, x + tmp->x, y + tmp->y, &sx, &sy);
+ if (!pos.normalise ())
+ return 1;
- if (flag & P_OUT_OF_MAP)
- return P_OUT_OF_MAP;
- if (flag & P_IS_ALIVE)
- return P_IS_ALIVE;
+ mapspace &ms = *pos;
- mapspace &ms = m1->at (sx, sy);
+ if (ms.flags () & P_IS_ALIVE)
+ return 1;
- /* find_first_free_spot() calls this function. However, often
- * ob doesn't have any move type (when used to place exits)
+ /* However, often ob doesn't have any move type
+ * (signifying non-moving objects)
* so the AND operation in OB_TYPE_MOVE_BLOCK doesn't work.
*/
-
- if (ob->move_type == 0 && ms.move_block != MOVE_ALL)
+ if (!move_type && ms.move_block != MOVE_ALL)
continue;
/* Note it is intentional that we check ob - the movement type of the
* head of the object should correspond for the entire object.
*/
- if (OB_TYPE_MOVE_BLOCK (ob, ms.move_block))
- return P_NO_PASS;
+ if (ms.blocks (move_type))
+ return 1;
}
return 0;
@@ -246,7 +225,7 @@
* The object 'container' is the object that contains the inventory.
* This is needed so that we can update the containers weight.
*/
-void
+static void
fix_container (object *container)
{
object *tmp = container->inv, *next;
@@ -262,12 +241,13 @@
tmp = next;
}
- /* sum_weight will go through and calculate what all the containers are
- * carrying.
- */
- sum_weight (container);
+ // go through and calculate what all the containers are carrying.
+ //TODO: remove
+ container->update_weight ();
}
+//-GPL
+
void
maptile::set_object_flag (int flag, int value)
{
@@ -279,6 +259,21 @@
tmp->flag [flag] = value;
}
+void
+maptile::post_load_original ()
+{
+ if (!spaces)
+ return;
+
+ set_object_flag (FLAG_OBJ_ORIGINAL);
+
+ for (mapspace *ms = spaces + size (); ms-- > spaces; )
+ for (object *tmp = ms->bot; tmp; tmp = tmp->above)
+ INVOKE_OBJECT (RESET, tmp);
+}
+
+//+GPL
+
/* link_multipart_objects go through all the objects on the map looking
* for objects whose arch says they are multipart yet according to the
* info we have, they only have the head (as would be expected when
@@ -315,6 +310,8 @@
}
}
+//-GPL
+
/*
* Loads (ands parses) the objects into a given map from the specified
* file pointer.
@@ -324,17 +321,40 @@
{
for (;;)
{
- coroapi::cede_to_tick_every (100); // cede once in a while
+ coroapi::cede_to_tick (); // cede once in a while
switch (f.kw)
{
case KW_arch:
if (object *op = object::read (f, this))
{
+ // TODO: why?
if (op->inv)
- sum_weight (op);
+ op->update_weight ();
- insert_ob_in_map (op, this, op, INS_NO_MERGE | INS_NO_WALK_ON | INS_ON_TOP | INS_MAP_LOAD);
+ if (IN_RANGE_EXC (op->x, 0, width) && IN_RANGE_EXC (op->y, 0, height))
+ {
+ // we insert manually because
+ // a) its way faster
+ // b) we remove manually, too, and there are good reasons for that
+ // c) it's correct
+ mapspace &ms = at (op->x, op->y);
+
+ op->flag [FLAG_REMOVED] = false;
+
+ op->above = 0;
+ op->below = ms.top;
+
+ *(ms.top ? &ms.top->above : &ms.bot) = op;
+
+ ms.top = op;
+ ms.flags_ = 0;
+ }
+ else
+ {
+ f.parse_warn (format ("object %s out of range", op->debug_desc ()));
+ op->destroy ();
+ }
}
continue;
@@ -462,6 +482,8 @@
spaces = salloc0 (size ());
}
+//+GPL
+
/* Takes a string from a map definition and outputs a pointer to the array of shopitems
* corresponding to that string. Memory is allocated for this, it must be freed
* at a later date.
@@ -547,34 +569,34 @@
/* opposite of parse string, this puts the string that was originally fed in to
* the map (or something equivilent) into output_string. */
-static void
-print_shop_string (maptile *m, char *output_string)
+static const char *
+print_shop_string (maptile *m)
{
- int i;
- char tmp[MAX_BUF];
+ static dynbuf_text buf; buf.clear ();
- strcpy (output_string, "");
- for (i = 0; i < m->shopitems[0].index; i++)
+ for (int i = 0; i < m->shopitems[0].index; i++)
{
if (m->shopitems[i].typenum)
{
if (m->shopitems[i].strength)
- sprintf (tmp, "%s:%d;", m->shopitems[i].name, m->shopitems[i].strength);
+ buf.printf ("%s:%d;", m->shopitems[i].name, m->shopitems[i].strength);
else
- sprintf (tmp, "%s;", m->shopitems[i].name);
+ buf.printf ("%s;", m->shopitems[i].name);
}
else
{
if (m->shopitems[i].strength)
- sprintf (tmp, "*:%d;", m->shopitems[i].strength);
+ buf.printf ("*:%d;", m->shopitems[i].strength);
else
- sprintf (tmp, "*");
+ buf.printf ("*");
}
-
- strcat (output_string, tmp);
}
+
+ return buf;
}
+//-GPL
+
/* This loads the header information of the map. The header
* contains things like difficulty, size, timeout, etc.
* this used to be stored in the map object, but with the
@@ -634,6 +656,7 @@
case KW_per_player: thawer.get (per_player); break;
case KW_per_party: thawer.get (per_party); break;
case KW_no_reset: thawer.get (no_reset); break;
+ case KW_no_drop: thawer.get (no_drop); break;
case KW_region: default_region = region::find (thawer.get_str ()); break;
case KW_shopitems: shopitems = parse_shop_string (thawer.get_str ()); break;
@@ -674,6 +697,8 @@
abort ();
}
+//+GPL
+
/******************************************************************************
* This is the start of unique map handling code
*****************************************************************************/
@@ -693,16 +718,15 @@
unique = 1;
if (op->head_ () == op && (QUERY_FLAG (op, FLAG_UNIQUE) || unique))
- {
- op->destroy_inv (false);
- op->destroy ();
- }
+ op->destroy ();
op = above;
}
}
}
+//-GPL
+
bool
maptile::_save_header (object_freezer &freezer)
{
@@ -717,21 +741,16 @@
MAP_OUT (reset_timeout);
MAP_OUT (fixed_resettime);
MAP_OUT (no_reset);
+ MAP_OUT (no_drop);
MAP_OUT (difficulty);
-
if (default_region) MAP_OUT2 (region, default_region->name);
- if (shopitems)
- {
- char shop[MAX_BUF];
- print_shop_string (this, shop);
- MAP_OUT2 (shopitems, shop);
- }
-
+ if (shopitems) MAP_OUT2 (shopitems, print_shop_string (this));
MAP_OUT (shopgreed);
MAP_OUT (shopmin);
MAP_OUT (shopmax);
if (shoprace) MAP_OUT (shoprace);
+
MAP_OUT (darkness);
MAP_OUT (width);
MAP_OUT (height);
@@ -774,30 +793,43 @@
return freezer.save (path);
}
+//+GPL
+
/*
* Remove and free all objects in the given map.
*/
void
maptile::clear ()
{
- sfree (regions, size ()); regions = 0;
- delete [] regionmap; regionmap = 0;
-
if (spaces)
{
for (mapspace *ms = spaces + size (); ms-- > spaces; )
while (object *op = ms->bot)
{
- op = op->head_ ();
- op->destroy_inv (false);
- op->destroy ();
+ // manually remove, as to not trigger anything
+ if (ms->bot = op->above)
+ ms->bot->below = 0;
+
+ op->flag [FLAG_REMOVED] = true;
+
+ object *head = op->head_ ();
+ if (op == head)
+ op->destroy ();
+ else if (head->map != op->map)
+ {
+ LOG (llevDebug, "bad luck for object crossing map borders: %s", head->debug_desc ());
+ head->destroy ();
+ }
}
- sfree (spaces, size ()), spaces = 0;
+ sfree0 (spaces, size ());
}
if (buttons)
free_objectlinkpt (buttons), buttons = 0;
+
+ sfree0 (regions, size ());
+ delete [] regionmap; regionmap = 0;
}
void
@@ -907,38 +939,14 @@
}
/*
- * Updates every button on the map (by calling update_button() for them).
- */
-void
-maptile::update_buttons ()
-{
- for (oblinkpt *obp = buttons; obp; obp = obp->next)
- for (objectlink *ol = obp->link; ol; ol = ol->next)
- {
- if (!ol->ob)
- {
- LOG (llevError, "Internal error in update_button (%s (%dx%d), connected %ld).\n",
- ol->ob ? (const char *) ol->ob->name : "null", ol->ob ? ol->ob->x : -1, ol->ob ? ol->ob->y : -1, obp->value);
- continue;
- }
-
- if (ol->ob->type == BUTTON || ol->ob->type == PEDESTAL)
- {
- update_button (ol->ob);
- break;
- }
- }
-}
-
-/*
* This routine is supposed to find out the difficulty of the map.
* difficulty does not have a lot to do with character level,
* but does have a lot to do with treasure on the map.
*
- * Difficulty can now be set by the map creature. If the value stored
- * in the map is zero, then use this routine. Maps should really
- * have a difficulty set than using this function - human calculation
- * is much better than this functions guesswork.
+ * Difficulty can now be set by the map creator. If the value stored
+ * in the map is zero, then use this routine. Maps should really
+ * have a difficulty set rather than using this function - human calculation
+ * is much better than this function's guesswork.
*/
int
maptile::estimate_difficulty () const
@@ -960,10 +968,17 @@
{
total_exp += op->stats.exp;
- if (archetype *at = type_to_archetype (GENERATE_TYPE (op)))
- total_exp += at->stats.exp * 8;
+ if (archetype *at = op->other_arch)
+ {
+ total_exp += at->stats.exp * 8;
+ monster_cnt++;
+ }
- monster_cnt++;
+ for (object *inv = op->inv; inv; inv = inv->below)
+ {
+ total_exp += op->stats.exp * 8;
+ monster_cnt++;
+ }
}
}
@@ -986,10 +1001,8 @@
int
maptile::change_map_light (int change)
{
- int new_level = darkness + change;
-
/* Nothing to do */
- if (!change || (new_level <= 0 && darkness == 0) || (new_level >= MAX_DARKNESS && darkness >= MAX_DARKNESS))
+ if (!change)
return 0;
/* inform all players on the map */
@@ -998,20 +1011,11 @@
else
new_info_map (NDI_BLACK | NDI_UNIQUE, this, "It becomes brighter.");
- /* Do extra checking. since darkness is a unsigned value,
- * we need to be extra careful about negative values.
- * In general, the checks below are only needed if change
- * is not +/-1
- */
- if (new_level < 0)
- darkness = 0;
- else if (new_level >= MAX_DARKNESS)
- darkness = MAX_DARKNESS;
- else
- darkness = new_level;
+ darkness = clamp (darkness + change, -MAX_DARKNESS, MAX_DARKNESS);
/* All clients need to get re-updated for the change */
update_all_map_los (this);
+
return 1;
}
@@ -1024,8 +1028,9 @@
void
mapspace::update_ ()
{
- object *tmp, *last = 0;
- uint8 flags = P_UPTODATE, light = 0, anywhere = 0;
+ object *last = 0;
+ uint8 flags = P_UPTODATE, anywhere = 0;
+ sint8 light = 0;
MoveType move_block = 0, move_slow = 0, move_on = 0, move_off = 0, move_allow = 0;
//object *middle = 0;
@@ -1036,15 +1041,10 @@
object *&middle = faces_obj[1] = 0;
object *&floor = faces_obj[2] = 0;
- for (tmp = bot; tmp; last = tmp, tmp = tmp->above)
+ for (object *tmp = bot; tmp; last = tmp, tmp = tmp->above)
{
- /* This could be made additive I guess (two lights better than
- * one). But if so, it shouldn't be a simple additive - 2
- * light bulbs do not illuminate twice as far as once since
- * it is a dissapation factor that is cubed.
- */
- if (tmp->glow_radius > light)
- light = tmp->glow_radius;
+ // Lights are additive, up to MAX_LIGHT_RADIUS, see los.C)
+ light += tmp->glow_radius;
/* This call is needed in order to update objects the player
* is standing in that have animations (ie, grass, fire, etc).
@@ -1073,6 +1073,7 @@
middle = tmp;
anywhere = 1;
}
+
/* Find the highest visible face around. If equal
* visibilities, we still want the one nearer to the
* top
@@ -1101,7 +1102,7 @@
if (QUERY_FLAG (tmp, FLAG_DAMNED)) flags |= P_NO_CLERIC;
}
- this->light = light;
+ this->light = min (light, MAX_LIGHT_RADIUS);
this->flags_ = flags;
this->move_block = move_block & ~move_allow;
this->move_on = move_on;
@@ -1131,7 +1132,7 @@
* 3) neither middle or top is set - need to set both.
*/
- for (tmp = last; tmp; tmp = tmp->below)
+ for (object *tmp = last; tmp; tmp = tmp->below)
{
/* Once we get to a floor, stop, since we already have a floor object */
if (QUERY_FLAG (tmp, FLAG_IS_FLOOR))
@@ -1193,17 +1194,17 @@
return vol;
}
-bool
+maptile *
maptile::tile_available (int dir, bool load)
{
- if (!tile_path[dir])
- return 0;
-
- if (tile_map[dir] && (!load || tile_map[dir]->in_memory == MAP_IN_MEMORY))
- return 1;
+ if (tile_path[dir])
+ {
+ if (tile_map[dir] && (!load || tile_map[dir]->in_memory == MAP_ACTIVE))
+ return tile_map[dir];
- if ((tile_map[dir] = find_async (tile_path[dir], this, load)))
- return 1;
+ if ((tile_map[dir] = find_async (tile_path[dir], this, load)))
+ return tile_map[dir];
+ }
return 0;
}
@@ -1519,8 +1520,8 @@
retval->distance_x += op2->x - x;
retval->distance_y += op2->y - y;
- retval->part = NULL;
- retval->distance = idistance (retval->distance_x, retval->distance_y);
+ retval->part = 0;
+ retval->distance = upos_max (abs (retval->distance_x), abs (retval->distance_y));
retval->direction = find_dir_2 (-retval->distance_x, -retval->distance_y);
}
}
@@ -1541,12 +1542,11 @@
return adjacent_map (op1->map, op2->map, &dx, &dy);
}
+//-GPL
+
object *
maptile::insert (object *op, int x, int y, object *originator, int flags)
{
- if (!op->flag [FLAG_REMOVED])
- op->remove ();
-
return insert_ob_in_map_at (op, this, originator, flags, x, y);
}
@@ -1565,12 +1565,12 @@
return ::region::default_region ();
}
+//+GPL
+
/* picks a random object from a style map.
- * Redone by MSW so it should be faster and not use static
- * variables to generate tables.
*/
object *
-maptile::pick_random_object () const
+maptile::pick_random_object (rand_gen &gen) const
{
/* while returning a null object will result in a crash, that
* is actually preferable to an infinite loop. That is because
@@ -1580,34 +1580,129 @@
*/
for (int i = 1000; --i;)
{
- object *pick = at (rndm (width), rndm (height)).bot;
+ object *pick = at (gen (width), gen (height)).bot;
// do not prefer big monsters just because they are big.
- if (pick && pick->head_ () == pick)
+ if (pick && pick->is_head ())
return pick->head_ ();
}
// instead of crashing in the unlikely(?) case, try to return *something*
- return get_archetype ("blocked");
+ return archetype::find ("bug");
}
+//-GPL
+
void
maptile::play_sound (faceidx sound, int x, int y) const
{
if (!sound)
return;
+ for_all_players_on_map (pl, this)
+ if (client *ns = pl->ns)
+ {
+ int dx = x - pl->ob->x;
+ int dy = y - pl->ob->y;
+
+ int distance = idistance (dx, dy);
+
+ if (distance <= MAX_SOUND_DISTANCE)
+ ns->play_sound (sound, dx, dy);
+ }
+}
+
+void
+maptile::say_msg (const char *msg, int x, int y) const
+{
for_all_players (pl)
- if (pl->observe->map == this)
- if (client *ns = pl->ns)
- {
- int dx = x - pl->ob->x;
- int dy = y - pl->ob->y;
+ if (client *ns = pl->ns)
+ {
+ int dx = x - pl->ob->x;
+ int dy = y - pl->ob->y;
- int distance = idistance (dx, dy);
+ int distance = idistance (dx, dy);
- if (distance <= MAX_SOUND_DISTANCE)
- ns->play_sound (sound, dx, dy);
- }
+ if (distance <= MAX_SOUND_DISTANCE)
+ ns->send_msg (NDI_GREY | NDI_DEF, SAY_CHANNEL, msg);
+ }
+}
+
+static void
+split_to_tiles (dynbuf &buf, maptile *m, int x0, int y0, int x1, int y1, int dx, int dy)
+{
+ // clip to map to the left
+ if (x0 < 0)
+ {
+ if (maptile *tile = m->tile_available (TILE_LEFT, 1))
+ split_to_tiles (buf, tile, x0 + tile->width, y0, min (x1 + tile->width, tile->width), y1, dx - tile->width, dy);
+
+ if (x1 < 0) // entirely to the left
+ return;
+
+ x0 = 0;
+ }
+
+ // clip to map to the right
+ if (x1 > m->width)
+ {
+ if (maptile *tile = m->tile_available (TILE_RIGHT, 1))
+ split_to_tiles (buf, tile, max (x0 - m->width, 0), y0, x1 - m->width, y1, dx + m->width, dy);
+
+ if (x0 > m->width) // entirely to the right
+ return;
+
+ x1 = m->width;
+ }
+
+ // clip to map above
+ if (y0 < 0)
+ {
+ if (maptile *tile = m->tile_available (TILE_UP, 1))
+ split_to_tiles (buf, tile, x0, y0 + tile->height, x1, min (y1 + tile->height, tile->height), dx, dy - tile->height);
+
+ if (y1 < 0) // entirely above
+ return;
+
+ y0 = 0;
+ }
+
+ // clip to map below
+ if (y1 > m->height)
+ {
+ if (maptile *tile = m->tile_available (TILE_DOWN, 1))
+ split_to_tiles (buf, tile, x0, max (y0 - m->height, 0), x1, y1 - m->height, dx, dy + m->height);
+
+ if (y0 > m->height) // entirely below
+ return;
+
+ y1 = m->height;
+ }
+
+ // if we get here, the rect is within the current map
+ maprect *r = (maprect *)buf.alloc (sizeof (maprect));
+
+ r->m = m;
+ r->x0 = x0;
+ r->y0 = y0;
+ r->x1 = x1;
+ r->y1 = y1;
+ r->dx = dx;
+ r->dy = dy;
+}
+
+maprect *
+maptile::split_to_tiles (int x0, int y0, int x1, int y1)
+{
+ static dynbuf buf (sizeof (maprect) * 8, sizeof (maprect) * 8);
+ buf.clear ();
+
+ ::split_to_tiles (buf, this, x0, y0, x1, y1, 0, 0);
+
+ // add end marker
+ maprect *r = (maprect *)buf.alloc (sizeof (maprect));
+ r->m = 0;
+
+ return (maprect *)buf.linearise ();
}