TileIndex Channel::split_tile_if_needed(TileIndex ti, Tile &tile) {
TileIndex new_root_index = TileIndex::null();
if (tile.binary_length() <= m_max_tile_size) return new_root_index;
Tile children[2];
TileIndex child_indexes[2];
if (verbosity) log_f("split_tile_if_needed: splitting tile %s", ti.to_string().c_str());
// If we're splitting an "all" tile, it means that until now the channel has only had one tile's worth of
// data, and that a proper root tile location couldn't be selected. Select a new root tile now.
if (ti.is_nonnegative_all()) {
// TODO: this breaks if all samples are at one time
ti = new_root_index = TileIndex::index_containing(Range(tile.first_sample_time(), tile.last_sample_time()));
if (verbosity) log_f("split_tile_if_needed: Moving root tile to %s", ti.to_string().c_str());
}
child_indexes[0]= ti.left_child();
child_indexes[1]= ti.right_child();
double split_time = ti.right_child().start_time();
split_samples(tile.double_samples, split_time, children[0], children[1]);
split_samples(tile.string_samples, split_time, children[0], children[1]);
for (int i = 0; i < 2; i++) {
assert(!has_tile(child_indexes[i]));
assert(split_tile_if_needed(child_indexes[i], children[i]) == TileIndex::null());
write_tile(child_indexes[i], children[i]);
}
create_parent_tile_from_children(ti, tile, children);
return new_root_index;
}
void read_tile_samples(KVS &store, int uid, std::string full_channel_name, TileIndex requested_index, TileIndex client_tile_index, std::vector<DataSample<T> > &samples, bool &binned)
{
Channel ch(store, uid, full_channel_name);
Tile tile;
TileIndex actual_index;
bool success = ch.read_tile_or_closest_ancestor(requested_index, actual_index, tile);
if (!success) {
log_f("gettile: no tile found for %s", requested_index.to_string().c_str());
} else {
log_f("gettile: requested %s: found %s", requested_index.to_string().c_str(), actual_index.to_string().c_str());
for (unsigned i = 0; i < tile.get_samples<T>().size(); i++) {
DataSample<T> &sample=tile.get_samples<T>()[i];
if (client_tile_index.contains_time(sample.time)) samples.push_back(sample);
}
}
if (samples.size() <= 512) {
binned = false;
} else {
// Bin
binned = true;
std::vector<DataAccumulator<T> > bins(512);
for (unsigned i = 0; i < samples.size(); i++) {
DataSample<T> &sample=samples[i];
bins[(int)floor(client_tile_index.position(sample.time)*512)] += sample;
}
samples.clear();
for (unsigned i = 0; i < bins.size(); i++) {
if (bins[i].weight > 0) samples.push_back(bins[i].get_sample());
}
}
}
void Channel::write_tile(TileIndex ti, const Tile &tile) {
std::string binary;
tile.to_binary(binary);
//assert(binary.size() <= m_max_tile_size);
m_kvs.set(tile_key(ti), binary);
total_tiles_written++;
if (verbosity) log_f("Channel: write_tile %s %s: %s",
descriptor().c_str(), ti.to_string().c_str(), tile.summary().c_str());
}
bool Channel::read_tile(TileIndex ti, Tile &tile) const {
std::string binary;
if (!m_kvs.get(tile_key(ti), binary)) return false;
total_tiles_read++;
tile.from_binary(binary);
if (verbosity) log_f("Channel: read_tile %s %s: %s",
descriptor().c_str(), ti.to_string().c_str(), tile.summary().c_str());
return true;
}
void Channel::create_parent_tile_from_children(TileIndex parent_index, Tile &parent, Tile children[]) {
// Subsample the children to create the parent
// when do we want to show original values?
// when do we want to do a real low-pass filter?
// do we need to filter more than just the child tiles? e.g. gaussian beyond the tile border
if (verbosity) log_f("Channel: creating parent %s from children %s, %s",
parent_index.to_string().c_str(),
parent_index.left_child().to_string().c_str(),
parent_index.right_child().to_string().c_str());
combine_samples(BT_CHANNEL_DOUBLE_SAMPLES, parent_index, parent.double_samples, children[0].double_samples, children[1].double_samples);
if (children[0].double_samples.size() + children[1].double_samples.size()) assert(parent.double_samples.size());
combine_samples(BT_CHANNEL_STRING_SAMPLES, parent_index, parent.string_samples, children[0].string_samples, children[1].string_samples);
if (children[0].string_samples.size() + children[1].string_samples.size()) assert(parent.string_samples.size());
parent.ranges = children[0].ranges;
parent.ranges.add(children[1].ranges);
}
bool Channel::delete_tile(TileIndex ti) {
return m_kvs.del(tile_key(ti));
if (verbosity) log_f("Channel: delete_tile %s %s",
descriptor().c_str(), ti.to_string().c_str());
}
