The International Simutrans Forum

const sint32 multiplied_number = umgebung_t::cities_ignore_height || welt == NULL ? anzahl : anzahl * 4;
<SKIP>
if(welt != NULL && !umgebung_t::cities_ignore_height)
    {
        pre_result = new weighted_vector_tpl<koord>(multiplied_number);
    }

 vector_tpl<koord>* stadt_t::random_place(const karte_t* wl, const sint32 anzahl, sint16 old_x, sint16 old_y)
 {
 	int cl = 0;
 	for (int i = 0; i < MAX_CLIMATES; i++) 
 	{
 		if (hausbauer_t::get_special(0, haus_besch_t::rathaus, wl->get_timeline_year_month(), false, (climate)i)) 
 		{
 			cl |= (1 << i);
 		}
 	}
 
 	// For clustering cities by climate type, we need a list of at least 4x the number of sites actually needed
 	// for towns so that, from that expanded list, the final locations can be chosen. 
	const sint32 multiplied_number = umgebung_t::cities_ignore_height || welt == NULL ? anzahl : anzahl * 4;
 
 	DBG_DEBUG("karte_t::init()", "get random places in climates %x", cl);
 	slist_tpl<koord>* list = wl->finde_plaetze(2, 3, (climate_bits)cl, old_x, old_y);
 	DBG_DEBUG("karte_t::init()", "found %i places", list->get_count());
	vector_tpl<koord>* result = new vector_tpl<koord>(anzahl);
	weighted_vector_tpl<koord>* pre_result;
	if(welt != NULL && !umgebung_t::cities_ignore_height)
	{
		pre_result = new weighted_vector_tpl<koord>(multiplied_number);
	}
 
 	for (int i = 0; i < multiplied_number; i++) 
 	{
 		int len = list->get_count();
 		// check distances of all cities to their respective neightbours
 		while (len > 0) 
 		{
 			int minimum_dist = 0x7FFFFFFF;  // init with maximum
 			koord k;
 			const int index = simrand(len);
 			k = list->at(index);
 			list->remove(k);
 			len--;
 
 			// check minimum distance
 			for (int j = 0; (j < i) && minimum_dist > minimum_city_distance; j++) 
 			{
 				int dist = koord_distance( k, (*pre_result)[j] );
 				if (minimum_dist > dist) 
 				{
 					minimum_dist = dist;
 				}
 			}
 			if (minimum_dist > minimum_city_distance) 
 			{
 				// all cities are far enough => ok, find next place

				if(welt != NULL && !umgebung_t::cities_ignore_height)
 				{
					const sint16 height_above_water = welt->lookup_hgt(k) - welt->get_grundw****er();
					uint32 weight;
					switch(height_above_water)
					{
					case 1:
						weight = 24;
						break;
					case 2:
						weight = 22;
						break;
					case 3:
						weight = 16;
						break;
					case 4:
						weight = 12;
						break;
					case 5:
						weight = 10;
						break;
					case 6:
						weight = 9;
						break;
					case 7:
						weight = 8;
						break;
					case 8:
						weight = 7;
						break;
					case 9:
						weight = 6;
						break;
					case 10:
						weight = 5;
						break;
					case 11:
						weight = 4;
						break;
					case 12:
					case 13:
						weight = 3;
						break;
					case 14:
					case 15:
						weight = 2;
						break;
					default:
						weight = 1;
					};
					pre_result->append(k, weight); 
 					break;
				}
				else
				{
					result->append(k);
 					break;
				}
 			}
 			// if we reached here, the city was not far enough => try again
 		}
 
 		if (len <= 0 && i < anzahl - 1) 
 		{
 			dbg->warning("stadt_t::random_place()", "Not enough places found!");
 			break;
 		}
 	}
 	list->clear();
 	delete list;
 
	if(welt != NULL && !umgebung_t::cities_ignore_height)
 	{
		uint16 weight = 0;
		const uint16 total_weight = pre_result->get_sum_weight();
		for (int i = 0; i < anzahl; i++) 
 		{
			// Now produce the real results from the pre-list.
			weight = simrand(total_weight);
			if(!result->append_unique(pre_result->at_weight(weight)))
			{
				i--;
			}
 		}

		pre_result->clear();
		delete pre_result;
	}
 
 	return result;