Differential D3035 Diff 17856 ps/trunk/source/graphics/ObjectBase.cpp

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ps/trunk/source/graphics/ObjectBase.cpp

Show First 20 Lines • Show All 528 Lines • ▼ Show 20 Lines	std::set<CStr> CObjectBase::CalculateRandomRemainingSelections(rng_t& rng, const std::vector<std::set<CStr>>& initialSelections) const
// In each group, if one of the variants has a name matching a string in		// In each group, if one of the variants has a name matching a string in
// 'selections', use that one.		// 'selections', use that one.
// If more than one matches, choose randomly from those matching ones.		// If more than one matches, choose randomly from those matching ones.
// If none match, choose randomly from all variants.		// If none match, choose randomly from all variants.
//		//
// When choosing randomly, make use of each variant's frequency. If all		// When choosing randomly, make use of each variant's frequency. If all
// variants have frequency 0, treat them as if they were 1.		// variants have frequency 0, treat them as if they were 1.

		CObjectManager::VariantDiversity diversity = m_ObjectManager.GetVariantDiversity();

for (std::vector<std::vector<Variant> >::const_iterator grp = m_VariantGroups.begin();		for (std::vector<std::vector<Variant> >::const_iterator grp = m_VariantGroups.begin();
grp != m_VariantGroups.end();		grp != m_VariantGroups.end();
++grp)		++grp)
{		{
// Ignore groups with nothing inside. (A warning will have been		// Ignore groups with nothing inside. (A warning will have been
// emitted by the loading code.)		// emitted by the loading code.)
if (grp->size() == 0)		if (grp->size() == 0)
continue;		continue;
Show All 33 Lines	else
// Sum the frequencies		// Sum the frequencies
int totalFreq = 0;		int totalFreq = 0;
for (size_t i = 0; i < grp->size(); ++i)		for (size_t i = 0; i < grp->size(); ++i)
totalFreq += (*grp)[i].m_Frequency;		totalFreq += (*grp)[i].m_Frequency;

// Someone might be silly and set all variants to have freq==0, in		// Someone might be silly and set all variants to have freq==0, in
// which case we just pretend they're all 1		// which case we just pretend they're all 1
bool allZero = (totalFreq == 0);		bool allZero = (totalFreq == 0);
if (allZero) totalFreq = (int)grp->size();		if (allZero)
		totalFreq = (int)grp->size();
// Choose a random number in the interval [0..totalFreq)
int randNum = boost::random::uniform_int_distribution<int>(0, totalFreq-1)(rng);

// and use that to choose one of the variants		// Choose a random number in the interval [0..totalFreq) to choose one of the variants.
		// If the diversity is "none", force 0 to return the first valid variant.
		int randNum = diversity == CObjectManager::VariantDiversity::NONE ? 0 : boost::random::uniform_int_distribution<int>(0, totalFreq-1)(rng);
for (size_t i = 0; i < grp->size(); ++i)		for (size_t i = 0; i < grp->size(); ++i)
{		{
randNum -= (allZero ? 1 : (*grp)[i].m_Frequency);		randNum -= (allZero ? 1 : (*grp)[i].m_Frequency);
if (randNum < 0)		if (randNum < 0)
{		{
remainingSelections.insert((*grp)[i].m_VariantName);
// (If this change to 'remainingSelections' interferes with earlier choices, then		// (If this change to 'remainingSelections' interferes with earlier choices, then
// we'll get some non-fatal inconsistencies that just break the randomness. But that		// we'll get some non-fatal inconsistencies that just break the randomness. But that
// shouldn't happen, much.)		// shouldn't happen, much.)
// (As an example, suppose you have a group with variants "a" and "b", and another		// (As an example, suppose you have a group with variants "a" and "b", and another
// with variants "a" and "c"; now if random selection choses "b" for the first		// with variants "a" and "c"; now if random selection choses "b" for the first
// and "a" for the second, then the selection of "a" from the second group will		// and "a" for the second, then the selection of "a" from the second group will
// cause "a" to be used in the first instead of the "b").		// cause "a" to be used in the first instead of the "b").
match = (int)i;		match = (int)i;

		// In limited diversity, somewhat-randomly continue. This cuts variants to about a third,
		// though not quite because we must pick a variant so the actual probability is more complex.
		// (It's also dependent on actor files not containing too many 0-frequency variants)
		if (diversity == CObjectManager::VariantDiversity::LIMITED && (i % 3 != 0))
		{
		// Reset to 0 or we'll just pick every subsequent variant.
		randNum = 0;
		continue;
		}
break;		break;
}		}
}		}
ENSURE(randNum < 0);		ENSURE(match != -1);
// This should always succeed; otherwise it		// This should always succeed; otherwise it
// wouldn't have chosen any of the variants.		// wouldn't have chosen any of the variants.
		remainingSelections.insert((*grp)[match].m_VariantName);
}		}
}		}

// Remember which props were chosen, so we can call CalculateRandomVariation on them		// Remember which props were chosen, so we can call CalculateRandomVariation on them
// at the end.		// at the end.
const Variant& var ((*grp)[match]);		const Variant& var ((*grp)[match]);
// Erase all existing props which are overridden by this variant:		// Erase all existing props which are overridden by this variant:
for (const Prop& prop : var.m_Props)		for (const Prop& prop : var.m_Props)
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