/**
* Tries to find a suitable destination for the given source and cargo.
* @param cid Subsidized cargo.
* @param src_type Type of \a src.
* @param src Index of source.
* @return True iff the subsidy was created.
*/
bool FindSubsidyCargoDestination(CargoID cid, SourceType src_type, SourceID src)
{
/* Choose a random destination. Only consider towns if they can accept the cargo. */
SourceType dst_type = (HasBit(_town_cargoes_accepted, cid) && Chance16(1, 2)) ? ST_TOWN : ST_INDUSTRY;
SourceID dst;
switch (dst_type) {
case ST_TOWN: {
/* Select a random town. */
const Town *dst_town = Town::GetRandom();
/* Check if the town can accept this cargo. */
if (!HasBit(dst_town->cargo_accepted_total, cid)) return false;
dst = dst_town->index;
break;
}
case ST_INDUSTRY: {
/* Select a random industry. */
const Industry *dst_ind = Industry::GetRandom();
/* The industry must accept the cargo */
if (dst_ind == NULL ||
(cid != dst_ind->accepts_cargo[0] &&
cid != dst_ind->accepts_cargo[1] &&
cid != dst_ind->accepts_cargo[2])) {
return false;
}
dst = dst_ind->index;
break;
}
default: NOT_REACHED();
}
/* Check that the source and the destination are not the same. */
if (src_type == dst_type && src == dst) return false;
/* Check distance between source and destination. */
if (!CheckSubsidyDistance(src_type, src, dst_type, dst)) return false;
/* Avoid duplicate subsidies. */
if (CheckSubsidyDuplicate(cid, src_type, src, dst_type, dst)) return false;
CreateSubsidy(cid, src_type, src, dst_type, dst);
return true;
}
/**
* Tries to find a suitable destination for the given source and cargo.
* @param cid Subsidized cargo.
* @param src_type Type of \a src.
* @param src Index of source.
* @return True iff the subsidy was created.
*/
bool FindSubsidyCargoDestination(CargoID cid, SourceType src_type, SourceID src)
{
/* Choose a random destination. Only consider towns if they can accept the cargo. */
SourceType dst_type = (HasBit(_town_cargoes_accepted, cid) && Chance16(1, 2)) ? ST_TOWN : ST_INDUSTRY;
CargoSourceSink *src_sink = (src_type == ST_TOWN) ? (CargoSourceSink *) Town::Get(src) : (CargoSourceSink *) Industry::Get(src);
SourceID dst;
switch (dst_type) {
case ST_TOWN: {
/* Select a random town. */
const Town *dst_town = NULL;
if (CargoHasDestinations(cid)) {
/* Try to get a town from the demand destinations. */
CargoLink *link = src_sink->GetRandomLink(cid, false);
if (link == src_sink->cargo_links[cid].End()) return NULL;
if (link->dest != NULL && link->dest->GetType() != dst_type) return NULL;
dst_town = static_cast<const Town *>(link->dest);
}
if (dst_town == NULL) dst_town = Town::GetRandom();
/* Check if the town can accept this cargo. */
if (!HasBit(dst_town->cargo_accepted_total, cid)) return false;
dst = dst_town->index;
break;
}
case ST_INDUSTRY: {
/* Select a random industry. */
const Industry *dst_ind = Industry::GetRandom();
if (CargoHasDestinations(cid)) {
/* Try to get a town from the demand destinations. */
CargoLink *link = src_sink->GetRandomLink(cid, false);
if (link == src_sink->cargo_links[cid].End()) return NULL;
if (link->dest != NULL && link->dest->GetType() != dst_type) return NULL;
dst_ind = static_cast<const Industry *>(link->dest);
}
if (dst_ind == NULL) dst_ind = Industry::GetRandom();
dst = dst_ind->index;
/* The industry must accept the cargo */
if (dst_ind == NULL || (src_type == dst_type && src == dst) ||
(cid != dst_ind->accepts_cargo[0] &&
cid != dst_ind->accepts_cargo[1] &&
cid != dst_ind->accepts_cargo[2])) {
return false;
}
break;
}
default: NOT_REACHED();
}
/* Check that the source and the destination are not the same. */
if (src_type == dst_type && src == dst) return false;
/* Check distance between source and destination. */
if (!CheckSubsidyDistance(src_type, src, dst_type, dst)) return false;
/* Avoid duplicate subsidies. */
if (CheckSubsidyDuplicate(cid, src_type, src, dst_type, dst)) return false;
CreateSubsidy(cid, src_type, src, dst_type, dst);
return true;
}
