void MetavoxelData::write(Bitstream& out) const {
out << _size;
out << _roots.size();
for (QHash<AttributePointer, MetavoxelNode*>::const_iterator it = _roots.constBegin(); it != _roots.constEnd(); it++) {
out.getAttributeStreamer() << it.key();
it.value()->write(it.key(), out);
}
}
void MetavoxelData::readDelta(const MetavoxelData& reference, Bitstream& in) {
// shallow copy the reference
*this = reference;
bool changed;
in >> changed;
if (!changed) {
return;
}
bool sizeChanged;
in >> sizeChanged;
if (sizeChanged) {
float size;
in >> size;
while (_size < size) {
expand();
}
}
int changedCount;
in >> changedCount;
for (int i = 0; i < changedCount; i++) {
AttributePointer attribute;
in.getAttributeStreamer() >> attribute;
MetavoxelNode*& root = _roots[attribute];
if (root) {
MetavoxelNode* oldRoot = root;
root = new MetavoxelNode(attribute);
root->readDelta(attribute, *oldRoot, in);
oldRoot->decrementReferenceCount(attribute);
} else {
root = new MetavoxelNode(attribute);
root->read(attribute, in);
}
}
int removedCount;
in >> removedCount;
for (int i = 0; i < removedCount; i++) {
AttributePointer attribute;
in.getAttributeStreamer() >> attribute;
_roots.take(attribute)->decrementReferenceCount(attribute);
}
}
void MetavoxelData::read(Bitstream& in) {
// clear out any existing roots
decrementRootReferenceCounts();
_roots.clear();
in >> _size;
// read in the new roots
int rootCount;
in >> rootCount;
for (int i = 0; i < rootCount; i++) {
AttributePointer attribute;
in.getAttributeStreamer() >> attribute;
MetavoxelNode*& root = _roots[attribute];
root = new MetavoxelNode(attribute);
root->read(attribute, in);
}
}
void MetavoxelData::writeDelta(const MetavoxelData& reference, Bitstream& out) const {
// first things first: there might be no change whatsoever
if (_size == reference._size && _roots == reference._roots) {
out << false;
return;
}
out << true;
// compare the size; if changed (rare), we must compare to the expanded reference
const MetavoxelData* expandedReference = &reference;
if (_size == reference._size) {
out << false;
} else {
out << true;
out << _size;
MetavoxelData* expanded = new MetavoxelData(reference);
while (expanded->_size < _size) {
expanded->expand();
}
expandedReference = expanded;
}
// count the number of roots added/changed, then write
int changedCount = 0;
for (QHash<AttributePointer, MetavoxelNode*>::const_iterator it = _roots.constBegin(); it != _roots.constEnd(); it++) {
MetavoxelNode* referenceRoot = expandedReference->_roots.value(it.key());
if (it.value() != referenceRoot) {
changedCount++;
}
}
out << changedCount;
for (QHash<AttributePointer, MetavoxelNode*>::const_iterator it = _roots.constBegin(); it != _roots.constEnd(); it++) {
MetavoxelNode* referenceRoot = expandedReference->_roots.value(it.key());
if (it.value() != referenceRoot) {
out.getAttributeStreamer() << it.key();
if (referenceRoot) {
it.value()->writeDelta(it.key(), *referenceRoot, out);
} else {
it.value()->write(it.key(), out);
}
}
}
// same with nodes removed
int removedCount = 0;
for (QHash<AttributePointer, MetavoxelNode*>::const_iterator it = expandedReference->_roots.constBegin();
it != expandedReference->_roots.constEnd(); it++) {
if (!_roots.contains(it.key())) {
removedCount++;
}
}
out << removedCount;
for (QHash<AttributePointer, MetavoxelNode*>::const_iterator it = expandedReference->_roots.constBegin();
it != expandedReference->_roots.constEnd(); it++) {
if (!_roots.contains(it.key())) {
out.getAttributeStreamer() << it.key();
}
}
// delete the expanded reference if we had to expand
if (expandedReference != &reference) {
delete expandedReference;
}
}