Method Iterator

src/vehicle.cpp:432–457

* Iterator constructor. * Find first vehicle near (x, y). */

 * Find first vehicle near (x, y).
 */
VehiclesNearTileXY::Iterator::Iterator(int32_t x, int32_t y, uint max_dist)
{
	/* There are no negative tile coordinates */
	this->pos_rect.left = std::max<int>(0, x - max_dist);
	this->pos_rect.right = std::max<int>(0, x + max_dist);
	this->pos_rect.top = std::max<int>(0, y - max_dist);
	this->pos_rect.bottom = std::max<int>(0, y + max_dist);

	if (2 * max_dist < TILE_HASH_MASK * TILE_SIZE) {
		/* Hash area to scan */
		this->hxmin = this->hx = GetTileHash1D(this->pos_rect.left / TILE_SIZE);
		this->hxmax = GetTileHash1D(this->pos_rect.right / TILE_SIZE);
		this->hymin = this->hy = GetTileHash1D(this->pos_rect.top / TILE_SIZE);
		this->hymax = GetTileHash1D(this->pos_rect.bottom / TILE_SIZE);
	} else {
		/* Scan all */
		this->hxmin = this->hx = 0;
		this->hxmax = TILE_HASH_MASK;
		this->hymin = this->hy = 0;
		this->hymax = TILE_HASH_MASK;
	}

	this->current_veh = _vehicle_tile_hash[ComposeTileHash(this->hx, this->hy)];
	this->SkipEmptyBuckets();
	this->SkipFalseMatches();
}

/**
 * Advance the internal state to the next potential vehicle.