1 files changed, 107 insertions, 0 deletions
diff --git a/world/node_tree.c b/world/node_tree.c
new file mode 100644
index 00000000..f6874711
--- /dev/null
+++ b/world/node_tree.c
@@ -0,0 +1,107 @@
+#include <fitz.h>
+
+fz_error *
+fz_newtree(fz_tree **treep)
+{
+	fz_tree *tree;
+
+	tree = *treep = fz_malloc(sizeof (fz_tree));
+	if (!tree)
+		return fz_outofmem;
+
+	tree->refs = 1;
+	tree->root = nil;
+	tree->head = nil;
+
+	return nil;
+}
+
+fz_tree *
+fz_keeptree(fz_tree *tree)
+{
+	tree->refs ++;
+	return tree;
+}
+
+void
+fz_droptree(fz_tree *tree)
+{
+	if (--tree->refs == 0)
+	{
+		if (tree->root)
+			fz_dropnode(tree->root);
+		fz_free(tree);
+	}
+}
+
+fz_rect
+fz_boundtree(fz_tree *tree, fz_matrix ctm)
+{
+	if (tree->root)
+		return fz_boundnode(tree->root, ctm);
+	return fz_emptyrect;
+}
+
+void
+fz_insertnodefirst(fz_node *parent, fz_node *child)
+{
+	child->parent = parent;
+	child->next = parent->first;
+	parent->first = child;
+	if (!parent->last)
+		parent->last = child;
+}
+
+void
+fz_insertnodelast(fz_node *parent, fz_node *child)
+{
+	child->parent = parent;
+	if (!parent->first)
+		parent->first = child;
+	else
+		parent->last->next = child;
+	parent->last = child;
+}
+
+void
+fz_insertnodeafter(fz_node *prev, fz_node *child)
+{
+	fz_node *parent = prev->parent;
+	child->parent = parent;
+	if (parent->last == prev)
+		parent->last = child;
+	child->next = prev->next;
+	prev->next = child;
+}
+
+void
+fz_removenode(fz_node *child)
+{
+	fz_node *parent = child->parent;
+	fz_node *prev;
+	fz_node *node;
+
+	if (parent->first == child)
+	{
+		parent->first = child->next;
+		if (parent->last == child)
+			parent->last = nil;
+		return;
+	}
+
+	prev = parent->first;
+	node = prev->next;
+
+	while (node)
+	{
+		if (node == child)
+		{
+			prev->next = child->next;
+		}
+		prev = node;
+		node = node->next;
+	}
+
+	parent->last = prev;
+}
+