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(svn r9391) -Documentation : correct Doxygen of comments and @file inclusion. Time for P and Q files

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This commit is contained in:
belugas
2007-03-21 17:42:43 +00:00
parent 57557ba599
commit ca2fc01944
7 changed files with 282 additions and 270 deletions
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280
src/pathfind.cpp
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@@ -1,5 +1,7 @@
/* $Id$ */
/** @file pathfind.cpp */
#include "stdafx.h"
#include "openttd.h"
#include "bridge_map.h"
@@ -15,7 +17,7 @@
#include "variables.h"
#include "depot.h"
// remember which tiles we have already visited so we don't visit them again.
/* remember which tiles we have already visited so we don't visit them again. */
static bool TPFSetTileBit(TrackPathFinder *tpf, TileIndex tile, int dir)
{
uint hash, val, offs;
@@ -65,7 +67,7 @@ static bool TPFSetTileBit(TrackPathFinder *tpf, TileIndex tile, int dir)
tpf->hash_tile[hash] = PATHFIND_GET_LINK_OFFS(tpf, link);
link->flags = tpf->hash_head[hash];
tpf->hash_head[hash] = 0xFFFF; /* multi link */
tpf->hash_head[hash] = 0xFFFF; // multi link
link->next = 0xFFFF;
}
@@ -142,9 +144,9 @@ static void TPFMode2(TrackPathFinder* tpf, TileIndex tile, DiagDirection directi
assert(tpf->tracktype == TRANSPORT_WATER);
// This addition will sometimes overflow by a single tile.
// The use of TILE_MASK here makes sure that we still point at a valid
// tile, and then this tile will be in the sentinel row/col, so GetTileTrackStatus will fail.
/* This addition will sometimes overflow by a single tile.
* The use of TILE_MASK here makes sure that we still point at a valid
* tile, and then this tile will be in the sentinel row/col, so GetTileTrackStatus will fail. */
tile = TILE_MASK(tile + TileOffsByDiagDir(direction));
if (++tpf->rd.cur_length > 50)
@@ -160,8 +162,8 @@ static void TPFMode2(TrackPathFinder* tpf, TileIndex tile, DiagDirection directi
if ( (bits & (bits - 1)) == 0 ) {
/* only one direction */
i = 0;
while (!(bits&1))
i++, bits>>=1;
while (!(bits & 1))
i++, bits >>= 1;
rd = tpf->rd;
goto continue_here;
@@ -172,7 +174,7 @@ static void TPFMode2(TrackPathFinder* tpf, TileIndex tile, DiagDirection directi
if (!(bits & 1)) continue;
rd = tpf->rd;
// Change direction 4 times only
/* Change direction 4 times only */
if ((byte)i != tpf->rd.pft_var6) {
if (++tpf->rd.depth > 4) {
tpf->rd = rd;
@@ -189,7 +191,7 @@ continue_here:;
}
tpf->rd = rd;
} while (++i, bits>>=1);
} while (++i, bits >>= 1);
}
@@ -284,7 +286,7 @@ static void TPFMode1(TrackPathFinder* tpf, TileIndex tile, DiagDirection directi
/* Check in case of rail if the owner is the same */
if (tpf->tracktype == TRANSPORT_RAIL) {
// don't enter train depot from the back
/* don't enter train depot from the back */
if (IsTileDepotType(tile, TRANSPORT_RAIL) && GetRailDepotDirection(tile) == direction) return;
if (IsTileType(tile_org, MP_RAILWAY) || IsTileType(tile_org, MP_STATION) || IsTileType(tile_org, MP_TUNNELBRIDGE))
@@ -292,12 +294,12 @@ static void TPFMode1(TrackPathFinder* tpf, TileIndex tile, DiagDirection directi
if (GetTileOwner(tile_org) != GetTileOwner(tile)) return;
}
// check if the new tile can be entered from that direction
/* check if the new tile can be entered from that direction */
if (tpf->tracktype == TRANSPORT_ROAD) {
// road stops and depots now have a track (r4419)
// don't enter road stop from the back
/* road stops and depots now have a track (r4419)
* don't enter road stop from the back */
if (IsStandardRoadStopTile(tile) && ReverseDiagDir(GetRoadStopDir(tile)) != direction) return;
// don't enter road depot from the back
/* don't enter road depot from the back */
if (IsTileDepotType(tile, TRANSPORT_ROAD) && ReverseDiagDir(GetRoadDepotDirection(tile)) != direction) return;
}
@@ -323,7 +325,7 @@ static void TPFMode1(TrackPathFinder* tpf, TileIndex tile, DiagDirection directi
if ((byte)bits != tpf->var2) {
bits &= _tpfmode1_and[direction];
bits = bits | (bits>>8);
bits = bits | (bits >> 8);
}
bits &= 0xBF;
@@ -333,7 +335,7 @@ static void TPFMode1(TrackPathFinder* tpf, TileIndex tile, DiagDirection directi
i = FIND_FIRST_BIT(bits);
bits = KILL_FIRST_BIT(bits);
tpf->the_dir = (Trackdir)((_otherdir_mask[direction] & (byte)(1 << i)) ? (i+8) : i);
tpf->the_dir = (Trackdir)((_otherdir_mask[direction] & (byte)(1 << i)) ? (i + 8) : i);
rd = tpf->rd;
if (TPFSetTileBit(tpf, tile, tpf->the_dir) &&
@@ -375,7 +377,7 @@ static void TPFMode1(TrackPathFinder* tpf, TileIndex tile, DiagDirection directi
i = FIND_FIRST_BIT(bits);
bits = KILL_FIRST_BIT(bits);
tpf->the_dir = (Trackdir)((_otherdir_mask[direction] & (byte)(1 << i)) ? (i+8) : i);
tpf->the_dir = (Trackdir)((_otherdir_mask[direction] & (byte)(1 << i)) ? (i + 8) : i);
rd = tpf->rd;
if (TPFSetTileBit(tpf, tile, tpf->the_dir) &&
!tpf->enum_proc(tile, tpf->userdata, tpf->the_dir, tpf->rd.cur_length, &tpf->rd.pft_var6) ) {
@@ -401,10 +403,10 @@ void FollowTrack(TileIndex tile, uint16 flags, DiagDirection direction, TPFEnumP
tpf.rd.depth = 0;
tpf.rd.pft_var6 = 0;
tpf.var2 = HASBIT(flags, 15) ? 0x43 : 0xFF; /* 0x8000 */
tpf.var2 = HASBIT(flags, 15) ? 0x43 : 0xFF; // 0x8000
tpf.disable_tile_hash = HASBIT(flags, 12); /* 0x1000 */
tpf.hasbit_13 = HASBIT(flags, 13); /* 0x2000 */
tpf.disable_tile_hash = HASBIT(flags, 12); // 0x1000
tpf.hasbit_13 = HASBIT(flags, 13); // 0x2000
tpf.tracktype = (TransportType)(flags & 0xFF);
@@ -425,8 +427,8 @@ void FollowTrack(TileIndex tile, uint16 flags, DiagDirection direction, TPFEnumP
struct StackedItem {
TileIndex tile;
uint16 cur_length; // This is the current length to this tile.
uint16 priority; // This is the current length + estimated length to the goal.
uint16 cur_length; ///< This is the current length to this tile.
uint16 priority; ///< This is the current length + estimated length to the goal.
TrackdirByte track;
byte depth;
byte state;
@@ -461,12 +463,12 @@ struct NewTrackPathFinder {
uint num_links_left;
uint nstack;
StackedItem stack[256]; // priority queue of stacked items
StackedItem stack[256]; ///< priority queue of stacked items
uint16 hash_head[0x400]; // hash heads. 0 means unused. 0xFFFC = length, 0x3 = dir
TileIndex hash_tile[0x400]; // tiles. or links.
uint16 hash_head[0x400]; ///< hash heads. 0 means unused. 0xFFFC = length, 0x3 = dir
TileIndex hash_tile[0x400]; ///< tiles. or links.
HashLink links[0x400]; // hash links
HashLink links[0x400]; ///< hash links
};
#define NTP_GET_LINK_OFFS(tpf, link) ((byte*)(link) - (byte*)tpf->links)
@@ -474,22 +476,22 @@ struct NewTrackPathFinder {
#define ARR(i) tpf->stack[(i)-1]
// called after a new element was added in the queue at the last index.
// move it down to the proper position
/** called after a new element was added in the queue at the last index.
* move it down to the proper position */
static inline void HeapifyUp(NewTrackPathFinder *tpf)
{
StackedItem si;
int i = ++tpf->nstack;
while (i != 1 && ARR(i).priority < ARR(i>>1).priority) {
// the child element is larger than the parent item.
// swap the child item and the parent item.
si = ARR(i); ARR(i) = ARR(i>>1); ARR(i>>1) = si;
i>>=1;
/* the child element is larger than the parent item.
* swap the child item and the parent item. */
si = ARR(i); ARR(i) = ARR(i >> 1); ARR(i >> 1) = si;
i >>= 1;
}
}
// called after the element 0 was eaten. fill it with a new element
/** called after the element 0 was eaten. fill it with a new element */
static inline void HeapifyDown(NewTrackPathFinder *tpf)
{
StackedItem si;
@@ -501,27 +503,27 @@ static inline void HeapifyDown(NewTrackPathFinder *tpf)
if (n == 0) return; // heap is empty so nothing to do?
// copy the last item to index 0. we use it as base for heapify.
ARR(1) = ARR(n+1);
/* copy the last item to index 0. we use it as base for heapify. */
ARR(1) = ARR(n + 1);
while ((j=i*2) <= n) {
// figure out which is smaller of the children.
if (j != n && ARR(j).priority > ARR(j+1).priority)
while ((j = i * 2) <= n) {
/* figure out which is smaller of the children. */
if (j != n && ARR(j).priority > ARR(j + 1).priority)
j++; // right item is smaller
assert(i <= n && j <= n);
if (ARR(i).priority <= ARR(j).priority)
break; // base elem smaller than smallest, done!
// swap parent with the child
/* swap parent with the child */
si = ARR(i); ARR(i) = ARR(j); ARR(j) = si;
i = j;
}
}
// mark a tile as visited and store the length of the path.
// if we already had a better path to this tile, return false.
// otherwise return true.
/** mark a tile as visited and store the length of the path.
* if we already had a better path to this tile, return false.
* otherwise return true. */
static bool NtpVisit(NewTrackPathFinder* tpf, TileIndex tile, DiagDirection dir, uint length)
{
uint hash,head;
@@ -531,7 +533,7 @@ static bool NtpVisit(NewTrackPathFinder* tpf, TileIndex tile, DiagDirection dir,
hash = PATHFIND_HASH_TILE(tile);
// never visited before?
/* never visited before? */
if ((head=tpf->hash_head[hash]) == 0) {
tpf->hash_tile[hash] = tile;
tpf->hash_head[hash] = dir | (length << 2);
@@ -541,15 +543,15 @@ static bool NtpVisit(NewTrackPathFinder* tpf, TileIndex tile, DiagDirection dir,
if (head != 0xffff) {
if (tile == tpf->hash_tile[hash] && (head & 0x3) == (uint)dir) {
// longer length
/* longer length */
if (length >= (head >> 2)) return false;
tpf->hash_head[hash] = dir | (length << 2);
return true;
}
// two tiles with the same hash, need to make a link
// allocate a link. if out of links, handle this by returning
// that a tile was already visisted.
/* two tiles with the same hash, need to make a link
* allocate a link. if out of links, handle this by returning
* that a tile was already visisted. */
if (tpf->num_links_left == 0) {
DEBUG(ntp, 1, "No links left");
return false;
@@ -564,12 +566,12 @@ static bool NtpVisit(NewTrackPathFinder* tpf, TileIndex tile, DiagDirection dir,
tpf->hash_tile[hash] = NTP_GET_LINK_OFFS(tpf, link);
link->typelength = tpf->hash_head[hash];
tpf->hash_head[hash] = 0xFFFF; /* multi link */
tpf->hash_head[hash] = 0xFFFF; // multi link
link->next = 0xFFFF;
} else {
// a linked list of many tiles,
// find the one corresponding to the tile, if it exists.
// otherwise make a new link
/* a linked list of many tiles,
* find the one corresponding to the tile, if it exists.
* otherwise make a new link */
uint offs = tpf->hash_tile[hash];
do {
@@ -623,7 +625,7 @@ static bool NtpCheck(NewTrackPathFinder *tpf, TileIndex tile, uint dir, uint len
return length == (head >> 2);
}
// else it's a linked list of many tiles
/* else it's a linked list of many tiles */
offs = tpf->hash_tile[hash];
for (;;) {
link = NTP_GET_LINK_PTR(tpf, offs);
@@ -638,21 +640,21 @@ static bool NtpCheck(NewTrackPathFinder *tpf, TileIndex tile, uint dir, uint len
static const uint16 _is_upwards_slope[15] = {
0, // no tileh
(1 << TRACKDIR_X_SW) | (1 << TRACKDIR_Y_NW), // 1
(1 << TRACKDIR_X_SW) | (1 << TRACKDIR_Y_SE), // 2
(1 << TRACKDIR_X_SW), // 3
(1 << TRACKDIR_X_NE) | (1 << TRACKDIR_Y_SE), // 4
0, // 5
(1 << TRACKDIR_Y_SE), // 6
0, // 7
(1 << TRACKDIR_X_NE) | (1 << TRACKDIR_Y_NW), // 8,
(1 << TRACKDIR_Y_NW), // 9
0, //10
0, //11,
(1 << TRACKDIR_X_NE), //12
0, //13
0, //14
0, ///< no tileh
(1 << TRACKDIR_X_SW) | (1 << TRACKDIR_Y_NW), ///< 1
(1 << TRACKDIR_X_SW) | (1 << TRACKDIR_Y_SE), ///< 2
(1 << TRACKDIR_X_SW), ///< 3
(1 << TRACKDIR_X_NE) | (1 << TRACKDIR_Y_SE), ///< 4
0, ///< 5
(1 << TRACKDIR_Y_SE), ///< 6
0, ///< 7
(1 << TRACKDIR_X_NE) | (1 << TRACKDIR_Y_NW), ///< 8,
(1 << TRACKDIR_Y_NW), ///< 9
0, ///< 10
0, ///< 11,
(1 << TRACKDIR_X_NE), ///< 12
0, ///< 13
0, ///< 14
};
static uint DistanceMoo(TileIndex t0, TileIndex t1)
@@ -660,27 +662,27 @@ static uint DistanceMoo(TileIndex t0, TileIndex t1)
const uint dx = delta(TileX(t0), TileX(t1));
const uint dy = delta(TileY(t0), TileY(t1));
const uint straightTracks = 2 * min(dx, dy); /* The number of straight (not full length) tracks */
const uint straightTracks = 2 * min(dx, dy); // The number of straight (not full length) tracks
/* OPTIMISATION:
* Original: diagTracks = max(dx, dy) - min(dx,dy);
* Proof:
* (dx-dy) - straightTracks == (min + max) - straightTracks = min + // max - 2 * min = max - min */
const uint diagTracks = dx + dy - straightTracks; /* The number of diagonal (full tile length) tracks. */
const uint diagTracks = dx + dy - straightTracks; // The number of diagonal (full tile length) tracks.
return diagTracks*DIAG_FACTOR + straightTracks*STR_FACTOR;
}
// These has to be small cause the max length of a track
// is currently limited to 16384
/* These has to be small cause the max length of a track
* is currently limited to 16384 */
static const byte _length_of_track[16] = {
DIAG_FACTOR, DIAG_FACTOR, STR_FACTOR, STR_FACTOR, STR_FACTOR, STR_FACTOR, 0, 0,
DIAG_FACTOR, DIAG_FACTOR, STR_FACTOR, STR_FACTOR, STR_FACTOR, STR_FACTOR, 0, 0
};
// new more optimized pathfinder for trains...
// Tile is the tile the train is at.
// direction is the tile the train is moving towards.
/* new more optimized pathfinder for trains...
* Tile is the tile the train is at.
* direction is the tile the train is moving towards. */
static void NTPEnum(NewTrackPathFinder* tpf, TileIndex tile, DiagDirection direction)
{
@@ -692,8 +694,8 @@ static void NTPEnum(NewTrackPathFinder* tpf, TileIndex tile, DiagDirection direc
// Need to have a special case for the start.
// We shouldn't call the callback for the current tile.
/* Need to have a special case for the start.
* We shouldn't call the callback for the current tile. */
si.cur_length = 1; // Need to start at 1 cause 0 is a reserved value.
si.depth = 0;
si.state = 0;
@@ -701,7 +703,7 @@ static void NTPEnum(NewTrackPathFinder* tpf, TileIndex tile, DiagDirection direc
goto start_at;
for (;;) {
// Get the next item to search from from the priority queue
/* Get the next item to search from from the priority queue */
do {
if (tpf->nstack == 0)
return; // nothing left? then we're done!
@@ -709,10 +711,10 @@ static void NTPEnum(NewTrackPathFinder* tpf, TileIndex tile, DiagDirection direc
tile = si.tile;
HeapifyDown(tpf);
// Make sure we havn't already visited this tile.
/* Make sure we havn't already visited this tile. */
} while (!NtpCheck(tpf, tile, _tpf_prev_direction[si.track], si.cur_length));
// Add the length of this track.
/* Add the length of this track. */
si.cur_length += _length_of_track[si.track];
callback_and_continue:
@@ -723,8 +725,8 @@ callback_and_continue:
direction = _tpf_new_direction[si.track];
start_at:
// If the tile is the entry tile of a tunnel, and we're not going out of the tunnel,
// need to find the exit of the tunnel.
/* If the tile is the entry tile of a tunnel, and we're not going out of the tunnel,
* need to find the exit of the tunnel. */
if (IsTileType(tile, MP_TUNNELBRIDGE)) {
if (IsTunnel(tile)) {
if (GetTunnelDirection(tile) != ReverseDiagDir(direction)) {
@@ -733,7 +735,7 @@ start_at:
/* We are not just driving out of the tunnel */
if (GetTunnelDirection(tile) != direction ||
GetTunnelTransportType(tile) != tpf->tracktype) {
// We are not driving into the tunnel, or it is an invalid tunnel
/* We are not driving into the tunnel, or it is an invalid tunnel */
continue;
}
if (!HASBIT(tpf->railtypes, GetRailType(tile))) {
@@ -743,15 +745,15 @@ start_at:
flotr = FindLengthOfTunnel(tile, direction);
si.cur_length += flotr.length * DIAG_FACTOR;
tile = flotr.tile;
// tile now points to the exit tile of the tunnel
/* tile now points to the exit tile of the tunnel */
}
} else {
TileIndex tile_end;
if (GetBridgeRampDirection(tile) != ReverseDiagDir(direction)) {
// We are not just leaving the bridge
/* We are not just leaving the bridge */
if (GetBridgeRampDirection(tile) != direction ||
GetBridgeTransportType(tile) != tpf->tracktype) {
// Not entering the bridge or not compatible
/* Not entering the bridge or not compatible */
continue;
}
}
@@ -761,29 +763,29 @@ start_at:
}
}
// This is a special loop used to go through
// a rail net and find the first intersection
/* This is a special loop used to go through
* a rail net and find the first intersection */
tile_org = tile;
for (;;) {
assert(direction <= 3);
tile += TileOffsByDiagDir(direction);
// too long search length? bail out.
/* too long search length? bail out. */
if (si.cur_length >= tpf->maxlength) {
DEBUG(ntp, 1, "Cur_length too big");
bits = TRACK_BIT_NONE;
break;
}
// Not a regular rail tile?
// Then we can't use the code below, but revert to more general code.
/* Not a regular rail tile?
* Then we can't use the code below, but revert to more general code. */
if (!IsTileType(tile, MP_RAILWAY) || !IsPlainRailTile(tile)) {
// We found a tile which is not a normal railway tile.
// Determine which tracks that exist on this tile.
/* We found a tile which is not a normal railway tile.
* Determine which tracks that exist on this tile. */
uint32 ts = GetTileTrackStatus(tile, TRANSPORT_RAIL) & _tpfmode1_and[direction];
bits = TrackdirBitsToTrackBits((TrackdirBits)(ts & TRACKDIR_BIT_MASK));
// Check that the tile contains exactly one track
/* Check that the tile contains exactly one track */
if (bits == 0 || KILL_FIRST_BIT(bits) != 0) break;
if (!HASBIT(tpf->railtypes, GetRailType(tile))) {
@@ -791,12 +793,12 @@ start_at:
break;
}
///////////////////
// If we reach here, the tile has exactly one track.
// tile - index to a tile that is not rail tile, but still straight (with optional signals)
// bits - bitmask of which track that exist on the tile (exactly one bit is set)
// direction - which direction are we moving in?
///////////////////
/*******************
* If we reach here, the tile has exactly one track.
* tile - index to a tile that is not rail tile, but still straight (with optional signals)
* bits - bitmask of which track that exist on the tile (exactly one bit is set)
* direction - which direction are we moving in?
*******************/
si.track = _new_trackdir[FIND_FIRST_BIT(bits)][direction];
si.cur_length += _length_of_track[si.track];
goto callback_and_continue;
@@ -825,89 +827,89 @@ start_at:
si.cur_length += _length_of_track[track];
// Check if this rail is an upwards slope. If it is, then add a penalty.
// Small optimization here.. if (track&7)>1 then it can't be a slope so we avoid calling GetTileSlope
/* Check if this rail is an upwards slope. If it is, then add a penalty.
* Small optimization here.. if (track&7)>1 then it can't be a slope so we avoid calling GetTileSlope */
if ((track & 7) <= 1 && (_is_upwards_slope[GetTileSlope(tile, NULL)] & (1 << track)) ) {
// upwards slope. add some penalty.
si.cur_length += 4*DIAG_FACTOR;
si.cur_length += 4 * DIAG_FACTOR;
}
// railway tile with signals..?
/* railway tile with signals..? */
if (HasSignals(tile)) {
if (!HasSignalOnTrackdir(tile, track)) {
// if one way signal not pointing towards us, stop going in this direction => End of rail segment.
/* if one way signal not pointing towards us, stop going in this direction => End of rail segment. */
if (HasSignalOnTrackdir(tile, ReverseTrackdir(track))) {
bits = TRACK_BIT_NONE;
break;
}
} else if (GetSignalStateByTrackdir(tile, track) == SIGNAL_STATE_GREEN) {
// green signal in our direction. either one way or two way.
/* green signal in our direction. either one way or two way. */
si.state |= 3;
} else {
// reached a red signal.
/* reached a red signal. */
if (HasSignalOnTrackdir(tile, ReverseTrackdir(track))) {
// two way red signal. unless we passed another green signal on the way,
// stop going in this direction => End of rail segment.
// this is to prevent us from going into a full platform.
if (!(si.state&1)) {
/* two way red signal. unless we passed another green signal on the way,
* stop going in this direction => End of rail segment.
* this is to prevent us from going into a full platform. */
if (!(si.state & 1)) {
bits = TRACK_BIT_NONE;
break;
}
}
if (!(si.state & 2)) {
// Is this the first signal we see? And it's red... add penalty
si.cur_length += 10*DIAG_FACTOR;
/* Is this the first signal we see? And it's red... add penalty */
si.cur_length += 10 * DIAG_FACTOR;
si.state += 2; // remember that we added penalty.
// Because we added a penalty, we can't just continue as usual.
// Need to get out and let A* do it's job with
// possibly finding an even shorter path.
/* Because we added a penalty, we can't just continue as usual.
* Need to get out and let A* do it's job with
* possibly finding an even shorter path. */
break;
}
}
if (tpf->enum_proc(tile, tpf->userdata, si.first_track, si.cur_length))
return; /* Don't process this tile any further */
return; // Don't process this tile any further
}
// continue with the next track
/* continue with the next track */
direction = _tpf_new_direction[track];
// safety check if we're running around chasing our tail... (infinite loop)
/* safety check if we're running around chasing our tail... (infinite loop) */
if (tile == tile_org) {
bits = TRACK_BIT_NONE;
break;
}
}
// There are no tracks to choose between.
// Stop searching in this direction
/* There are no tracks to choose between.
* Stop searching in this direction */
if (bits == TRACK_BIT_NONE)
continue;
////////////////
// We got multiple tracks to choose between (intersection).
// Branch the search space into several branches.
////////////////
/****************
* We got multiple tracks to choose between (intersection).
* Branch the search space into several branches.
****************/
// Check if we've already visited this intersection.
// If we've already visited it with a better length, then
// there's no point in visiting it again.
/* Check if we've already visited this intersection.
* If we've already visited it with a better length, then
* there's no point in visiting it again. */
if (!NtpVisit(tpf, tile, direction, si.cur_length))
continue;
// Push all possible alternatives that we can reach from here
// onto the priority heap.
// 'bits' contains the tracks that we can choose between.
/* Push all possible alternatives that we can reach from here
* onto the priority heap.
* 'bits' contains the tracks that we can choose between. */
// First compute the estimated distance to the target.
// This is used to implement A*
/* First compute the estimated distance to the target.
* This is used to implement A* */
estimation = 0;
if (tpf->dest != 0)
estimation = DistanceMoo(tile, tpf->dest);
si.depth++;
if (si.depth == 0)
continue; /* We overflowed our depth. No more searching in this direction. */
continue; // We overflowed our depth. No more searching in this direction.
si.tile = tile;
while (bits != TRACK_BIT_NONE) {
Track track = RemoveFirstTrack(&bits);
@@ -915,7 +917,7 @@ start_at:
assert(si.track != 0xFF);
si.priority = si.cur_length + estimation;
// out of stack items, bail out?
/* out of stack items, bail out? */
if (tpf->nstack >= lengthof(tpf->stack)) {
DEBUG(ntp, 1, "Out of stack");
break;
@@ -925,9 +927,9 @@ start_at:
HeapifyUp(tpf);
};
// If this is the first intersection, we need to fill the first_track member.
// so the code outside knows which path is better.
// also randomize the order in which we search through them.
/* If this is the first intersection, we need to fill the first_track member.
* so the code outside knows which path is better.
* also randomize the order in which we search through them. */
if (si.depth == 1) {
assert(tpf->nstack == 1 || tpf->nstack == 2 || tpf->nstack == 3);
if (tpf->nstack != 1) {
@@ -944,12 +946,12 @@ start_at:
}
}
// Continue with the next from the queue...
/* Continue with the next from the queue... */
}
}
// new pathfinder for trains. better and faster.
/** new pathfinder for trains. better and faster. */
void NewTrainPathfind(TileIndex tile, TileIndex dest, RailTypeMask railtypes, DiagDirection direction, NTPEnumProc* enum_proc, void* data)
{
NewTrackPathFinder tpf;