From 2123ba02410cfa426f1b9791b4eed0db2fbae175 Mon Sep 17 00:00:00 2001
From: shun-iwasawa <shun.iwasawa@ghibli.jp>
Date: Tue, 23 Aug 2022 15:39:52 +0900
Subject: [PATCH] fix crash on replacing level:

---
 toonz/sources/toonz/levelsettingspopup.cpp | 5 ++++-
 toonz/sources/toonz/previewfxmanager.cpp   | 1 +
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/toonz/sources/toonz/levelsettingspopup.cpp b/toonz/sources/toonz/levelsettingspopup.cpp
index daa61b96..911d5abe 100644
--- a/toonz/sources/toonz/levelsettingspopup.cpp
+++ b/toonz/sources/toonz/levelsettingspopup.cpp
@@ -761,7 +761,7 @@ LevelSettingsValues LevelSettingsPopup::getValues(TXshLevelP level) {
       values.doAntialias = (sl->getProperties()->antialiasSoftness() > 0)
                                ? Qt::Checked
                                : Qt::Unchecked;
-      values.softness = sl->getProperties()->antialiasSoftness();
+      values.softness    = sl->getProperties()->antialiasSoftness();
     }
   }
 
@@ -1475,6 +1475,7 @@ void LevelSettingsPopup::onSubsamplingChanged() {
     return;
   }
 
+  bool somethingChanged = false;
   TUndoManager::manager()->beginBlock();
   QSetIterator<TXshLevelP> levelItr(m_selectedLevels);
   while (levelItr.hasNext()) {
@@ -1491,8 +1492,10 @@ void LevelSettingsPopup::onSubsamplingChanged() {
     TUndoManager::manager()->add(new LevelSettingsUndo(
         levelP.getPointer(), LevelSettingsUndo::Subsampling, oldSubsampling,
         subsampling));
+    somethingChanged = true;
   }
   TUndoManager::manager()->endBlock();
+  if (!somethingChanged) return;
 
   TApp::instance()->getCurrentScene()->setDirtyFlag(true);
   TApp::instance()
diff --git a/toonz/sources/toonz/previewfxmanager.cpp b/toonz/sources/toonz/previewfxmanager.cpp
index ccffbfbc..169204a0 100644
--- a/toonz/sources/toonz/previewfxmanager.cpp
+++ b/toonz/sources/toonz/previewfxmanager.cpp
@@ -1456,6 +1456,7 @@ void PreviewFxManager::onLevelChanged() {
     // Build the level name as an alias keyword. All cache images associated
     // with an alias containing the level name will be updated.
     TXshLevel *xl = TApp::instance()->getCurrentLevel()->getLevel();
+    if (!xl) return;
     std::string aliasKeyword;
     TFilePath fp = xl->getPath();
     aliasKeyword = ::to_string(fp.withType(""));