bool Channel::read_tile_or_closest_ancestor(TileIndex ti, TileIndex &ret_index, Tile &ret) const {
Locker lock(*this); // Lock self and hold lock until exiting this method
ChannelInfo info;
bool success = read_info(info);
if (!success) {
if (verbosity) log_f("read_tile_or_closest_ancestor: can't read info");
return false;
}
TileIndex root = info.nonnegative_root_tile_index;
if (ti.is_ancestor_of(root)) {
ret_index = root;
} else {
if (ti != root && !root.is_ancestor_of(ti)) {
// Tile isn't under root
return false;
}
assert(tile_exists(root));
ret_index = root;
while (ret_index != ti) {
TileIndex child = ti.start_time() < ret_index.left_child().end_time() ? ret_index.left_child() : ret_index.right_child();
if (!tile_exists(child)) break;
ret_index = child;
}
}
// ret_index now holds closest ancestor to ti (or ti itself if it exists)
assert(read_tile(ret_index, ret));
return true;
}
TileIndex Channel::find_successive_tile(TileIndex root, TileIndex ti, int desired_level) const {
// Move upwards until parent has a different end time
while (1) {
if (ti.parent().is_null()) return TileIndex::null();
if (ti.parent().end_time() != ti.end_time()) break;
ti = ti.parent();
if (ti.level >= root.level) {
// No more underneath the root
return TileIndex::null();
}
}
// We are now the left child of our parent; skip to the right child
ti = ti.sibling();
return find_child_overlapping_time(ti, ti.start_time(), desired_level);
}
void Channel::read_bottommost_tiles_in_range(Range times,
bool (*callback)(const Tile &t, Range times)) const {
ChannelInfo info;
bool success = read_info(info);
if (!success) return;
if (!info.times.intersects(times)) return;
double time = times.min;
TileIndex ti = TileIndex::null();
while (time < times.max) {
if (ti.is_null()) {
ti = find_lowest_child_overlapping_time(info.nonnegative_root_tile_index, times.min);
} else {
ti = find_lowest_successive_tile(info.nonnegative_root_tile_index, ti);
}
if (ti.is_null() || ti.start_time() >= times.max) break;
Tile t;
assert(read_tile(ti, t));
if (!(*callback)(t, times)) break;
}
}
