From 91aa397b043aa0f3afe4f5c3360b318acea84387 Mon Sep 17 00:00:00 2001
From: ousnius <ousnius@users.noreply.github.com>
Date: Sun, 25 Feb 2018 19:42:26 +0100
Subject: [PATCH] Load, save and optimize NIFs without a root node

---
 lib/NIF/BasicTypes.cpp |  6 ++++++
 lib/NIF/NifFile.cpp    | 12 +++++++-----
 2 files changed, 13 insertions(+), 5 deletions(-)

diff --git a/lib/NIF/BasicTypes.cpp b/lib/NIF/BasicTypes.cpp
index 2f1159ab..29bcd812 100644
--- a/lib/NIF/BasicTypes.cpp
+++ b/lib/NIF/BasicTypes.cpp
@@ -257,6 +257,9 @@ void NiHeader::SetBlockOrder(std::vector<std::pair<int, int>>& newIndices) {
 		return p.first == 0xFFFFFFFF;
 	}), newIndices.end());
 
+	if (newIndices.empty())
+		return;
+
 	for (int i = 0; i < newIndices.size() - 1; i++) {
 		bool swapped = false;
 		for (int j = 0; j < newIndices.size() - i - 1; j++) {
@@ -308,6 +311,9 @@ bool NiHeader::IsBlockReferenced(const int blockId) {
 }
 
 void NiHeader::DeleteUnreferencedBlocks(const int rootId, bool* hadDeletions) {
+	if (rootId == 0xFFFFFFFF)
+		return;
+
 	for (int i = 0; i < numBlocks; i++) {
 		if (i != rootId && !IsBlockReferenced(i)) {
 			DeleteBlock(i);
diff --git a/lib/NIF/NifFile.cpp b/lib/NIF/NifFile.cpp
index 001c5917..a4394ce3 100644
--- a/lib/NIF/NifFile.cpp
+++ b/lib/NIF/NifFile.cpp
@@ -810,10 +810,6 @@ OptResultSSE NifFile::OptimizeForSSE(const OptOptionsSSE& options) {
 	version.SetStream(100);
 
 	for (auto &shape : GetShapes()) {
-		NiNode* parentNode = GetParentNode(shape);
-		if (!parentNode)
-			continue;
-
 		std::string shapeName = shape->GetName();
 
 		auto geomData = hdr.GetBlock<NiGeometryData>(shape->GetDataRef());
@@ -1051,6 +1047,11 @@ OptResultSSE NifFile::OptimizeForSSE(const OptOptionsSSE& options) {
 	}
 
 	DeleteUnreferencedBlocks();
+
+	// For files without a root node, remove the leftover data blocks anyway
+	hdr.DeleteBlockByType("NiTriStripsData");
+	hdr.DeleteBlockByType("NiTriShapeData");
+
 	return result;
 }
 
@@ -1178,7 +1179,8 @@ bool NifFile::RenameDuplicateShapes() {
 	auto nodes = GetChildren<NiNode>();
 
 	auto root = GetRootNode();
-	nodes.push_back(root);
+	if (root)
+		nodes.push_back(root);
 
 	for (auto &node : nodes) {
 		int dupCount = 0;