/**
* Called by YAPF to calculate cost estimate. Calculates distance to the destination
* adds it to the actual cost from origin and stores the sum to the Node::m_estimate
*/
inline bool PfCalcEstimate(Node& n)
{
static const int dg_dir_to_x_offs[] = {-1, 0, 1, 0};
static const int dg_dir_to_y_offs[] = {0, 1, 0, -1};
if (PfDetectDestination(n)) {
n.m_estimate = n.m_cost;
return true;
}
TileIndex tile = n.m_segment_last_tile;
DiagDirection exitdir = TrackdirToExitdir(n.m_segment_last_td);
int x1 = 2 * TileX(tile) + dg_dir_to_x_offs[(int)exitdir];
int y1 = 2 * TileY(tile) + dg_dir_to_y_offs[(int)exitdir];
int x2 = 2 * TileX(m_destTile);
int y2 = 2 * TileY(m_destTile);
int dx = abs(x1 - x2);
int dy = abs(y1 - y2);
int dmin = min(dx, dy);
int dxy = abs(dx - dy);
int d = dmin * YAPF_TILE_CORNER_LENGTH + (dxy - 1) * (YAPF_TILE_LENGTH / 2);
n.m_estimate = n.m_cost + d;
assert(n.m_estimate >= n.m_parent->m_estimate);
return true;
}
/** Called by YAPF to detect if node ends in the desired destination */
FORCEINLINE bool PfDetectDestination(Node& n)
{
return PfDetectDestination(n.GetLastTile(), n.GetLastTrackdir());
}