/// <summary>
/// path search (x0,y0).(x1,y1)
/// <para>
/// flag & 1 = easy path search only
/// </para>
/// </summary>
/// <param name="wpd">path info will be written here</param>
/// <param name="m">map to check the path on</param>
/// <param name="x0">start X</param>
/// <param name="y0">start Y</param>
/// <param name="x1">end X</param>
/// <param name="y1">end Y</param>
/// <param name="flag">&1 = easy path search only</param>
/// <param name="cell">type of obstruction to check for</param>
/// <returns></returns>
public static bool SearchPath(out WalkpathData wpd, Map m, int x0, int y0, int x1, int y1, int flag, ECollisionType cell) {
int[] heap = new int[MAX_HEAP + 1];
STmpPath[] tp = new STmpPath[MAX_WALKPATH * MAX_WALKPATH];
int i, j, len, x, y, dx, dy;
int rp, xs, ys;
wpd = new WalkpathData();
//Do not check starting cell as that would get you stuck.
if (x0 < 0 || x0 >= m.Width || y0 < 0 || y0 >= m.Height /*|| m.CheckTile(x0,y0,cell) == false*/ )
return false;
if (x1 < 0 || x1 >= m.Width || y1 < 0 || y1 >= m.Height || m.CheckCell(x1, y1, cell) == false)
return false;
// calculate (sgn(x1-x0), sgn(y1-y0))
dx = ((dx = x1 - x0) > 0) ? ((dx < 0) ? -1 : 1) : 0;
dy = ((dy = y1 - y0) > 0) ? ((dy < 0) ? -1 : 1) : 0;
// try finding direct path to target
x = x0;
y = y0;
i = 0;
while (i < wpd.path.Length) {
wpd.path[i] = WalkChoises[-dy + 1][dx + 1];
i++;
x += dx;
y += dy;
if (x == x1)
dx = 0;
if (y == y1)
dy = 0;
if (dx == 0 && dy == 0)
break; // success
if (m.CheckCell(x, y, cell) == false)
break; // obstacle = failure
}
if (x == x1 && y == y1) { //easy path successful.
wpd.path_len = (uint)i;
wpd.path_pos = 0;
return true;
}
if ((flag & 1) == 1)
return false;
i = CalcIndex(x0, y0);
tp[i].x = (short)x0;
tp[i].y = (short)y0;
tp[i].dist = 0;
tp[i].before = 0;
tp[i].cost = (short)CalcCost(tp[i], x1, y1);
tp[i].flag = 0;
heap[0] = 0;
PushHeapPath(heap, tp, CalcIndex(x0, y0));
xs = m.Width - 1; // ‚ ‚ç‚©‚¶‚ß‚PŒ¸ŽZ‚µ‚Ä‚¨‚
ys = m.Height - 1;
while (true) {
int e = 0, f = 0;
int dist;
int cost;
int[] dc = new int[4];
if (heap[0] == 0)
return false;
rp = PopHeapPath(heap, tp);
x = tp[rp].x;
y = tp[rp].y;
dist = tp[rp].dist + 10;
cost = tp[rp].cost;
if (x == x1 && y == y1)
break;
// dc[0] : y++
// dc[1] : x--
// dc[2] : y--
// dc[3] : x++
if (y < ys && m.CheckCell(x, y + 1, cell)) {
f |= 1;
dc[0] = (y >= y1 ? 20 : 0);
e += AddPath(heap, tp, x, y + 1, dist, rp, cost + dc[0]); // (x, y+1)
}
if (x > 0 && m.CheckCell(x - 1, y, cell)) {
f |= 2;
dc[1] = (x <= x1 ? 20 : 0);
e += AddPath(heap, tp, x - 1, y, dist, rp, cost + dc[1]); // (x-1, y )
}
if (y > 0 && m.CheckCell(x, y - 1, cell)) {
f |= 4;
dc[2] = (y <= y1 ? 20 : 0);
e += AddPath(heap, tp, x, y - 1, dist, rp, cost + dc[2]); // (x , y-1)
}
if (x < xs && m.CheckCell(x + 1, y, cell)) {
f |= 8;
dc[3] = (x >= x1 ? 20 : 0);
e += AddPath(heap, tp, x + 1, y, dist, rp, cost + dc[3]); // (x+1, y )
}
if ((f & (2 + 1)) == (2 + 1) && m.CheckCell(x - 1, y + 1, cell))
e += AddPath(heap, tp, x - 1, y + 1, dist + 4, rp, cost + dc[1] + dc[0] - 6); // (x-1, y+1)
if ((f & (2 + 4)) == (2 + 4) && m.CheckCell(x - 1, y - 1, cell))
e += AddPath(heap, tp, x - 1, y - 1, dist + 4, rp, cost + dc[1] + dc[2] - 6); // (x-1, y-1)
if ((f & (8 + 4)) == (8 + 4) && m.CheckCell(x + 1, y - 1, cell))
e += AddPath(heap, tp, x + 1, y - 1, dist + 4, rp, cost + dc[3] + dc[2] - 6); // (x+1, y-1)
if ((f & (8 + 1)) == (8 + 1) && m.CheckCell(x + 1, y + 1, cell))
e += AddPath(heap, tp, x + 1, y + 1, dist + 4, rp, cost + dc[3] + dc[0] - 6); // (x+1, y+1)
tp[rp].flag = 1;
if (e > 0 || heap[0] >= MAX_HEAP - 5)
return false;
}
if (!(x == x1 && y == y1)) // will never happen...
return false;
for (len = 0, i = rp; len < 100 && i != CalcIndex(x0, y0); i = tp[i].before, len++) {
}
if (len == 100 || len >= wpd.path.Length)
return false;
wpd.path_len = (uint)len;
wpd.path_pos = 0;
for (i = rp, j = len - 1; j >= 0; i = tp[i].before, j--) {
dx = tp[i].x - tp[tp[i].before].x;
dy = tp[i].y - tp[tp[i].before].y;
Point2D p = new Point2D(dx, dy);
wpd.path[j] = p.ToDirection();
}
return true;
}
/// <summary>
/// path search (x0,y0).(x1,y1)
/// <para>
/// flag & 1 = easy path search only
/// </para>
/// </summary>
/// <param name="wpd">path info will be written here</param>
/// <param name="m">map to check the path on</param>
/// <param name="pStart">start-point</param>
/// <param name="pEnd">end-point</param>
/// <param name="flag">&1 = easy path search only</param>
/// <param name="cell">type of obstruction to check for</param>
/// <returns></returns>
public static bool SearchPath(out WalkpathData wpd, Map m, Point2D pStart, Point2D pEnd, int flag, ECollisionType cell) {
return SearchPath(out wpd, m, pStart.X, pStart.Y, pEnd.X, pEnd.Y, flag, cell);
}
/// <summary>
/// path search (x0,y0).(x1,y1) (walkable)
/// <para>
/// flag & 1 = easy path search only
/// </para>
/// </summary>
/// <param name="wpd">path info will be written here</param>
/// <param name="m">map to check the path on</param>
/// <param name="pStart">start-point</param>
/// <param name="pEnd">end-point</param>
/// <param name="flag">&1 = easy path search only</param>
/// <returns></returns>
public static bool SearchPath(out WalkpathData wpd, Map m, Point2D pStart, Point2D pEnd, int flag) {
return SearchPath(out wpd, m, pStart, pEnd, flag, ECollisionType.Walkable);
}
/// <summary>
/// path search (x0,y0).(x1,y1) (walkable)
/// </summary>
/// <param name="wpd">path info will be written here</param>
/// <param name="m">map to check the path on</param>
/// <param name="pStart">start-point</param>
/// <param name="pEnd">end-point</param>
/// <returns></returns>
public static bool SearchPath(out WalkpathData wpd, Map m, Point2D pStart, Point2D pEnd) {
return SearchPath(out wpd, m, pStart, pEnd, 0);
}
/*==========================================
* is ranged attack from (x0,y0) to (x1,y1) possible?
*------------------------------------------*/
public static bool SearchLongPath(ShootpathData spd, Map m, int x0, int y0, int x1, int y1, ECollisionType cell) {
int dx, dy;
int wx = 0, wy = 0;
int weight;
if (spd == null)
spd = new ShootpathData(); // use dummy output variable
dx = (x1 - x0);
if (dx < 0) {
x0 = x0.Swap(ref x1);
y0 = y0.Swap(ref y1);
dx = -dx;
}
dy = (y1 - y0);
spd.rx = spd.ry = 0;
spd.len = 1;
spd.x[0] = x0;
spd.y[0] = y0;
if (m.CheckCell(x1, y1, cell))
return false;
if (dx > Math.Abs(dy)) {
weight = dx;
spd.ry = 1;
} else {
weight = Math.Abs(y1 - y0);
spd.rx = 1;
}
while (x0 != x1 || y0 != y1) {
if (m.CheckCell(x0, y0, cell))
return false;
wx += dx;
wy += dy;
if (wx >= weight) {
wx -= weight;
x0++;
}
if (wy >= weight) {
wy -= weight;
y0++;
} else if (wy < 0) {
wy += weight;
y0--;
}
if (spd.len < MAX_WALKPATH) {
spd.x[spd.len] = x0;
spd.y[spd.len] = y0;
spd.len++;
}
}
return true;
}
/*==========================================
* Find the closest reachable cell,
* 'count' cells away from (x0,y0) in direction (dx,dy).
*------------------------------------------*/
public static int BlownPos(Map m, int x0, int y0, int dx, int dy, int count) {
if (count > 25) { //Cap to prevent too much processing...?
ServerConsole.ErrorLine("path_blownpos: count too many {0}!", count);
count = 25;
}
if (dx > 1 || dx < -1 || dy > 1 || dy < -1) {
ServerConsole.ErrorLine("path_blownpos: illegal dx={0} or dy={1} !", dx, dy);
dx = (dx > 0) ? 1 : ((dx < 0) ? -1 : 0);
dy = (dy > 0) ? 1 : ((dy < 0) ? -1 : 0);
}
while (count > 0 && (dx != 0 || dy != 0)) {
if (!m.CheckCell(x0 + dx, y0 + dy, ECollisionType.Walkable)) {// attempt partial movement
bool fx = (dx != 0 && m.CheckCell(x0 + dx, y0, ECollisionType.Walkable));
bool fy = (dy != 0 && m.CheckCell(x0, y0 + dy, ECollisionType.Walkable));
if (fx && fy) {
if (RandomWay.Next(0, 1) == 1)
dx = 0;
else
dy = 0;
}
if (!fx)
dx = 0;
if (!fy)
dy = 0;
}
x0 += dx;
y0 += dy;
count--;
}
return (x0 << 16) | y0; //TODO: use 'struct point' here instead?
}
