void
SoSwitch::write(SoWriteAction *action)
//
////////////////////////////////////////////////////////////////////////
{
SoOutput *out = action->getOutput();
// When writing out a switch that is in a path, we always want to
// write out ALL children of the switch. If we did the default
// thing of writing out just those children that affect the nodes
// in the path, we could screw up. Consider a switch that has two
// child separators and whichChild set to 1. If a path goes
// through the switch to the second child, the first child, being
// a separator, does not affect the path. But if we don't write
// out the separator, the whichChild will reference a
// nonexistent child. So we always write out all children.
// NOTE: SoChildList::traverse() checks the current path code and
// skips children off the path that do not affect the
// state. Because of this we have to avoid calling it. Instead, we
// do its work here.
// This code is stolen and modified from SoGroup::write() and
// SoChildList::traverse()
int lastChild = getNumChildren() - 1;
SoAction::PathCode pc = action->getCurPathCode();
// In write-reference counting phase
if (out->getStage() == SoOutput::COUNT_REFS) {
// Increment our write reference count
addWriteReference(out);
// If this is the first reference (i.e., we don't now have
// multiple references), also count all appropriate children
if (! hasMultipleWriteRefs()) {
for (int i = 0; i <= lastChild; i++) {
action->pushCurPath(i);
action->traverse(getChild(i));
action->popCurPath(pc);
}
}
}
// In writing phase, we have to do some more work
else if (! writeHeader(out, TRUE, FALSE)) {
// Write fields
const SoFieldData *fieldData = getFieldData();
fieldData->write(out, this);
// We KNOW that all children should be written, so don't
// bother calling shouldWrite()
// If writing binary format, write out number of children
// that are going to be written
if (out->isBinary())
out->write(getNumChildren());
for (int i = 0; i <= lastChild; i++) {
action->pushCurPath(i);
action->traverse(getChild(i));
action->popCurPath(pc);
}
// Write post-children stuff
writeFooter(out);
}
}
