GLK: FROTZ: Add support for pair windows to have more than 2 children

This is primarily for the V6 games, which have up to 8 windows
on-screen at the same time in arbitray positions
ext

1 files changed, 5 insertions, 4 deletions

diff --git a/engines/glk/glk_api.cpp b/engines/glk/glk_api.cpp
index e2da31706a..6e0f33ea56 100644
--- a/engines/glk/glk_api.cpp
+++ b/engines/glk/glk_api.cpp
@@ -258,10 +258,11 @@ winid_t GlkAPI::glk_window_get_sibling(winid_t win) {
 	if (!parentWin)
 		return nullptr;
 
-	if (parentWin->_child1 == win)
-		return parentWin->_child2;
-	else if (parentWin->_child2 == win)
-		return parentWin->_child1;
+	int index = parentWin->_children.indexOf(win);
+	if (index == ((int)parentWin->_children.size() - 1))
+		return parentWin->_children.front();
+	else if (index >= 0)
+		return parentWin->_children[index + 1];
 
 	return nullptr;
 }