From 565e759a92bdfea25cdd376ce5b27b8165a9c2aa Mon Sep 17 00:00:00 2001
From: shun-iwasawa <shun-iwasawa@users.noreply.github.com>
Date: Jun 19 2018 09:36:11 +0000
Subject: fix undo / redo of move mutiple columns (#2085)



---

diff --git a/toonz/sources/toonz/xsheetdragtool.cpp b/toonz/sources/toonz/xsheetdragtool.cpp
index 6c0001b..6909626 100644
--- a/toonz/sources/toonz/xsheetdragtool.cpp
+++ b/toonz/sources/toonz/xsheetdragtool.cpp
@@ -1632,6 +1632,9 @@ public:
       col    = currEnd;
     int dCol = col - (m_lastCol - m_offset);
 
+    // ignore if the cursor moves in the drag-starting column
+    if (dCol == 0) return;
+
     int newBegin = *indices.begin() + dCol;
     int newEnd   = *indices.rbegin() + dCol;
 
@@ -1641,8 +1644,10 @@ public:
              newEnd > currEnd)
       dCol -= (newEnd - currEnd);
 
-    if (col == (m_lastCol - m_offset)) return;
-    m_lastCol = col + m_offset;
+    // ignore if the dragged columns comes up against the end of column stack
+    if (dCol == 0) return;
+
+    m_lastCol += dCol;
 
     assert(*indices.begin() + dCol >= 0);