Small simplification/optimization of propagate_invalidation()

This commit is contained in:
Ali El Gariani 2009-05-17 22:38:03 +00:00
parent 356c19fb33
commit d0228ccad5

View file

@ -2334,28 +2334,22 @@ bool display::propagate_invalidation(const std::set<map_location>& locs)
if(invalidateAll_)
return false;
bool has_inval = false;
if(locs.size()<=1)
return false; // propagation never needed
// search the first hex invalidated (if any)
std::set<map_location>::const_iterator i = locs.begin();
for(; i != locs.end(); ++i) {
if (invalidated_.count(*i)) {
has_inval = true;
break; // 'i' will be used later
}
}
for(; i != locs.end() && invalidated_.count(*i) == 0 ; ++i) {}
// if no invalidation or one but nothing to propagate, return false
if (!has_inval || locs.size()<=1)
return false;
if (i == locs.end())
return false; // no invalidation, don't propagate
// propagate invalidation (but skip the already invalidated hex)
bool res = false;
std::set<map_location>::const_iterator j = locs.begin();
for(; j != locs.end(); ++j) {
if(j != i)
res |= invalidated_.insert(*j).second;
}
return res; // always true, but cleaner like that
// propagate invalidation
// 'i' is already in, but I suspect that splitting the range is bad
// especially because locs are often adjacents
size_t previous_size = invalidated_.size();
invalidated_.insert(locs.begin(), locs.end());
return previous_size < invalidated_.size();
}
bool display::invalidate_visible_locations_in_rect(const SDL_Rect& rect)