- speeded up pasting, shrinking parts, drawing controllers in

  the ctrlcanvas and reordering the drum list
- applyOperationGroup() now doesn't apply empty opGroups any more
- reordering the drum list doesn't cause undo be triggered any more
- removed unneccessary song->update() calls after a
  song->applyOperationGroup() call
- cleaned up (removed some commented out code blocks)

12 files changed, 77 insertions, 462 deletions

diff --git a/muse2/muse/ctrl/ctrlcanvas.cpp b/muse2/muse/ctrl/ctrlcanvas.cpp
index f2f335cf..d1d6b2fa 100644
--- a/muse2/muse/ctrl/ctrlcanvas.cpp
+++ b/muse2/muse/ctrl/ctrlcanvas.cpp
@@ -545,14 +545,6 @@ void CtrlCanvas::partControllers(const MidiPart* part, int num, int* dnum, int*
       }
       *mcvl = tmcvl;
       
-      // Removed by T356.
-      // MidiCtrlValList not found is now an acceptable state (for multiple part editing).
-      //if (i == cvll->end()) {
-      //      printf("CtrlCanvas::setController(0x%x): not found\n", num);
-      //      for (i = cvll->begin(); i != cvll->end(); ++i)
-      //            printf("  0x%x\n", i->second->num());
-      //      return;
-      //      }
     }    
   }
 }
@@ -566,98 +558,9 @@ void CtrlCanvas::updateItems()
       selection.clear();
       items.clearDelete();
       
-      /*
-      if(ctrl)
-      {
-        for(ciMidiCtrlVal imcv = ctrl->begin(); imcv != ctrl->end(); ++imcv)
-        {
-          MidiPart* part = (MidiPart*)imcv->part;
-          int val = imcv->val;
-          
-          bool edpart = false;
-          if(editor->parts()->index(part) != -1)
-            edpart = true;
-          
-          MidiController* mc;
-          MidiCtrlValList* mcvl;
-          partControllers(part, _cnum, 0, 0, &mc, &mcvl);
-
-          Event e(Controller);
-          
-          if(_cnum == CTRL_VELOCITY && e.type() == Note)
-          {
-            items.add(new CEvent(e, part, e.velo()));
-           
-          }
-          
-        }
-      }
-      */
-      
-      /*
-      MidiTrackList* mtl = song->midis();
-      for(ciMidiTrack imt = mtl->begin(); imt != mtl->end(); ++imt)
-      {
-        //MidiTrack* mt = *imt;
-        PartList* pl = (*imt)->parts();
-        for(ciPart p = pl->begin(); p != pl->end(); ++p) 
-        {
-          MidiPart* part = (MidiPart*)(p->second);
-          
-          bool edpart = false;
-          if(editor->parts()->index(part) != -1)
-            edpart = true;
-          
-          EventList* el = part->events();
-          MidiController* mc;
-          MidiCtrlValList* mcvl;
-          partControllers(part, _cnum, 0, 0, &mc, &mcvl);
-
-          for(iEvent i = el->begin(); i != el->end(); ++i) 
-          {
-            Event e = i->second;
-            if(_cnum == CTRL_VELOCITY && e.type() == Note) 
-            {
-              if(curDrumInstrument == -1) 
-              {
-                    items.add(new CEvent(e, part, e.velo()));
-              }
-              else if (e.dataA() == curDrumInstrument) //same note
-                    items.add(new CEvent(e, part, e.velo()));
-            }
-            else if (e.type() == Controller && e.dataA() == _didx) 
-            {
-              if(mcvl && last.empty()) 
-              {
-                    Event le(Controller);
-                    //le.setType(Controller);
-                    le.setA(_didx);
-                    //le.setB(e.dataB());
-                    le.setB(CTRL_VAL_UNKNOWN);
-                    //lastce = new CEvent(Event(), part, mcvl->value(part->tick(), part));
-                    //lastce = new CEvent(le, part, mcvl->value(part->tick(), part));
-                    lastce = new CEvent(le, part, mcvl->value(part->tick()));
-                    items.add(lastce);
-              }
-              if (lastce)
-                    lastce->setEX(e.tick());
-              lastce = new CEvent(e, part, e.dataB());
-              items.add(lastce);
-              last = e;
-            }    
-          }
-        }
-      }
-      */
-      
-      
-      
-      
       
       if(!editor->parts()->empty())
       {
-        //Event last;
-        //CEvent* lastce  = 0;
         CEvent *newev = 0;
   
         for (iPart p = editor->parts()->begin(); p != editor->parts()->end(); ++p) 
@@ -790,7 +693,6 @@ void CtrlCanvas::viewMousePressEvent(QMouseEvent* event)
                     }
                     if(do_redraw)
                       redraw();                 // Let songChanged handle the redraw upon SC_SELECTION.
-                      //song->update(SC_SELECTION); //
                   }
                   
                   
@@ -947,11 +849,8 @@ void CtrlCanvas::viewMouseReleaseEvent(QMouseEvent* event)
                               }  
                           }
                     drag = DRAG_OFF;
-                    //if(do_redraw)
-                    //  redraw();                 // Let songChanged handle the redraw upon SC_SELECTION.
+                      // Let songChanged handle the redraw upon SC_SELECTION.
                       song->update(SC_SELECTION); //
-                    //else
-                    //  redraw();  
                   }
                   break;
 
@@ -995,7 +894,7 @@ void CtrlCanvas::newValRamp(int x1, int y1, int x2, int y2)
         useRaster = true;
       }  
 
-      song->startUndo();
+      Undo operations;
 
       // delete existing events
 
@@ -1003,44 +902,29 @@ void CtrlCanvas::newValRamp(int x1, int y1, int x2, int y2)
       int lastpv = CTRL_VAL_UNKNOWN;
       for (ciCEvent i = items.begin(); i != items.end(); ++i) {
             CEvent* ev = *i;
-            if(ev->part() != curPart)
+            if (ev->part() != curPart)
               continue;
             Event event = ev->event();
             if (event.empty())
                   continue;
             int x = event.tick() + curPartTick;
-            //printf("CtrlCanvas::newValRamp x:%d xx1:%d xx2:%d len:%d\n", x, xx1, xx2, curPart->lenTick());
             
             if (x < xx1)
-            {
-            //      if(event.dataB() != CTRL_VAL_UNKNOWN)
-            //        lastpv = event.dataB();
                   continue;
-            }      
-            //if (x <= xx1)
-            //{
-            //      if(type == CTRL_PROGRAM && event.dataB() != CTRL_VAL_UNKNOWN && ((event.dataB() & 0xffffff) != 0xffffff))
-            //        lastpv = event.dataB();
-            //      if (x < xx1)
-            //        continue;
-            //}
+
             if (x >= xx2)
                   break;
             
-            // Indicate no undo, and do port controller values and clone parts. 
-            audio->msgDeleteEvent(event, curPart, false, true, true);
+            // Do port controller values and clone parts. 
+            operations.push_back(UndoOp(UndoOp::DeleteEvent, event, curPart, true, true));
             }
 
-      //if(type == CTRL_PROGRAM && lastpv == CTRL_VAL_UNKNOWN)
-      if(ctrl)  
+      if (ctrl)  
         lastpv = ctrl->hwVal();
         
       unsigned curPartLen = curPart->lenTick();
       
       // insert new events
-      //for (int x = xx1; x < xx2; x += raster) {
-      //      int y    = (x2==x1) ? y1 : (((y2-y1)*(x-x1))/(x2-x1))+y1;
-      //      int nval = computeVal(_controller, y, height());
       for (int x = xx1, step; x < xx2 ; x += step )    
       {
             step = useRaster ? raster : editor->rasterVal2(x + 1) - x;
@@ -1048,21 +932,18 @@ void CtrlCanvas::newValRamp(int x1, int y1, int x2, int y2)
             int y    = x + step >= xx2 || x2 == x1 ? y2 : (x == xx1 ? y1 : (((y2 - y1) * (x + step/2 - x1)) / (x2 - x1)) + y1);
             int nval = computeVal(_controller, y, height());
             
-            //int tick = x - curPartTick;
             unsigned tick = x - curPartTick;
-            //printf("CtrlCanvas::newValRamp x:%d xx1:%d xx2:%d step:%d newtick:%d\n", x, xx1, xx2, step, tick);  
             // Do not add events which are past the end of the part.
-            //if((unsigned)tick >= curPartLen)
-            if(tick >= curPartLen)
+            if (tick >= curPartLen)
               break;
             Event event(Controller);
             event.setTick(tick);
             event.setA(_didx);
-            if(type == CTRL_PROGRAM)
+            if (type == CTRL_PROGRAM)
             {
-              if(lastpv == CTRL_VAL_UNKNOWN)
+              if (lastpv == CTRL_VAL_UNKNOWN)
               {
-                if(song->mtype() == MT_GM)
+                if (song->mtype() == MT_GM)
                   event.setB(0xffff00 | (nval - 1));
                 else  
                   event.setB(nval - 1);
@@ -1073,13 +954,11 @@ void CtrlCanvas::newValRamp(int x1, int y1, int x2, int y2)
             else  
               event.setB(nval);
             
-            // Indicate no undo, and do port controller values and clone parts. 
-            audio->msgAddEvent(event, curPart, false, true, true);
+            // Do port controller values and clone parts. 
+            operations.push_back(UndoOp(UndoOp::AddEvent, event, curPart, true, true));
             }
               
-      ///song->update(0);
-      ///redraw();
-      song->endUndo(SC_EVENT_MODIFIED | SC_EVENT_INSERTED | SC_EVENT_REMOVED);
+      song->applyOperationGroup(operations);
       }
 
 //---------------------------------------------------------
@@ -1091,27 +970,24 @@ void CtrlCanvas::changeValRamp(int x1, int y1, int x2, int y2)
       int h   = height();
       bool changed = false;
       int type = _controller->num();
-      //int xx1 = editor->rasterVal1(x1);
 
-      song->startUndo();
+      Undo operations;
       for (ciCEvent i = items.begin(); i != items.end(); ++i) {
             if ((*i)->contains(x1, x2)) {
-            //if ((*i)->contains(xx1, x2)) {
                   CEvent* ev       = *i;
-                  if(ev->part() != curPart)
+                  if (ev->part() != curPart)
                     continue;
+
                   Event event = ev->event();
                   if (event.empty())
                         continue;
 
-                  //MidiPart* part   = ev->part();
-                  //int x    = event.tick() + ev->part()->tick();
                   int x    = event.tick() + curPart->tick();
                   int y    = (x2==x1) ? y1 : (((y2-y1)*(x-x1))/(x2-x1))+y1;
                   int nval = computeVal(_controller, y, h);
-                  if(type == CTRL_PROGRAM)
+                  if (type == CTRL_PROGRAM)
                   {
-                    if(event.dataB() == CTRL_VAL_UNKNOWN)
+                    if (event.dataB() == CTRL_VAL_UNKNOWN)
                     {
                       --nval;
                       if(song->mtype() == MT_GM)
@@ -1123,16 +999,13 @@ void CtrlCanvas::changeValRamp(int x1, int y1, int x2, int y2)
                     
                   ev->setVal(nval);
                   
-                  //MidiController::ControllerType type = midiControllerType(_controller->num());
-                  //if (type == MidiController::Velo) {
                   if (type == CTRL_VELOCITY) {
                         if ((event.velo() != nval)) {
                               Event newEvent = event.clone();
                               newEvent.setVelo(nval);
                               ev->setEvent(newEvent);
-                              // Indicate no undo, and do not do port controller values and clone parts. 
-                              audio->msgChangeEvent(event, newEvent, curPart, false, false, false);
-                              ///ev->setEvent(newEvent);
+                              // Do not do port controller values and clone parts. 
+                              operations.push_back(UndoOp(UndoOp::ModifyEvent, newEvent, event, curPart, false, false));
                               changed = true;
                               }
                         }
@@ -1142,34 +1015,16 @@ void CtrlCanvas::changeValRamp(int x1, int y1, int x2, int y2)
                                     Event newEvent = event.clone();
                                     newEvent.setB(nval);
                                     ev->setEvent(newEvent);
-                                    // Indicate no undo, and do port controller values and clone parts. 
-                                    audio->msgChangeEvent(event, newEvent, curPart, false, true, true);
-                                    ///ev->setEvent(newEvent);
+                                    // Do port controller values and clone parts. 
+                                    operations.push_back(UndoOp(UndoOp::ModifyEvent, newEvent, event, curPart, true, true));
                                     changed = true;
                                     }
                               }
-                        else {
-                              //if(!ctrl)
-                              //{
-                              //  ctrl = 
-                              //}
-                                
-                              // Removed by T356. Never gets here? A good thing, don't wan't auto-create values.
-                              //int oval = ctrl->value(0);
-                              //if (oval != nval) {
-                                    // Changed by T356.
-                                    //ctrl->add(0, nval);
-                              //      ctrl->add(0, nval, part);
-                              //      changed = true;
-                              //      }
-                              
-                              }
                         }
                   }
             }
-      ///if (changed)
-      ///      redraw();
-      song->endUndo(SC_EVENT_MODIFIED);
+
+      song->applyOperationGroup(operations);
       }
 
 //---------------------------------------------------------
@@ -1181,7 +1036,6 @@ void CtrlCanvas::changeVal(int x1, int x2, int y)
       bool changed = false;
       int newval = computeVal(_controller, y, height());
       int type = _controller->num();
-      //int xx1 = editor->rasterVal1(x1);
 
       for (ciCEvent i = items.begin(); i != items.end(); ++i) {
             if (!(*i)->contains(x1, x2))
@@ -1191,26 +1045,7 @@ void CtrlCanvas::changeVal(int x1, int x2, int y)
             if(ev->part() != curPart)
               continue;
             Event event      = ev->event();
-            //if(event.tick() >= curPart->lenTick())
-            //  break;
-              
-            //MidiPart* part   = ev->part();
-            //int nval = newval;
-            //if(type == CTRL_PROGRAM)
-            //{
-            //  if(event.dataB() == CTRL_VAL_UNKNOWN)
-            //  {
-            //    --nval;
-            //    if(song->mtype() == MT_GM)
-            //      nval |= 0xffff00;
-            //  }
-            //  else  
-            //    nval = (event.dataB() & 0xffff00) | (nval - 1);
-            //}
-            //ev->setVal(nval);
-            
-            //MidiController::ControllerType type = midiControllerType(_controller->num());
-            //if (type == MidiController::Velo) {
+
             if (type == CTRL_VELOCITY) {
                   if ((event.velo() != newval)) {
                         ev->setVal(newval);
@@ -1249,160 +1084,12 @@ void CtrlCanvas::changeVal(int x1, int x2, int y)
                               changed = true;
                               }
                         }
-                  else {
-                        //if(!ctrl)
-                        //{
-                        //  ctrl = 
-                        //}
-                          
-                        // Removed by T356. Never gets here? A good thing, don't wan't auto-create values.
-                        //int oval = ctrl->value(0);
-                        //if (oval != nval) {
-                              // Changed by T356.
-                              //ctrl->add(0, nval);
-                        //      ctrl->add(0, nval, part);
-                        //      changed = true;
-                        //      }
-                        }
                   }
             }
       if (changed)
             redraw();
       }
 
-/*
-//---------------------------------------------------------
-//   newVal
-//---------------------------------------------------------
-
-void CtrlCanvas::newVal(int x1, int x2, int y)
-      {
-      int xx1  = editor->rasterVal1(x1);
-      int xx2  = editor->rasterVal2(x2);
-      int newval = computeVal(_controller, y, height());
-      int type = _controller->num();
-
-      bool found        = false;
-      bool song_changed = false;
-
-      int lastpv = CTRL_VAL_UNKNOWN;
-      if(ctrl)
-        lastpv = ctrl->hwVal();
-        
-      for (ciCEvent i = items.begin(); i != items.end(); ++i) {
-            CEvent* ev = *i;
-            if(ev->part() != curPart)
-              continue;
-            //int partTick = ev->part()->tick();
-            int partTick = curPart->tick();
-            Event event = ev->event();
-            if (event.empty())
-                  continue;
-            int ax = event.tick() + partTick;
-            //printf("CtrlCanvas::newVal ax:%d xx1:%d xx2:%d len:%d\n", ax, xx1, xx2, curPart->lenTick());  
-            
-            if (ax < xx1)
-                  continue;
-            //if(ax <= xx1)
-            //{
-            //  if(type == CTRL_PROGRAM && event.dataB() != CTRL_VAL_UNKNOWN && ((event.dataB() & 0xffffff) != 0xffffff))
-            //    lastpv = event.dataB();
-            //  if(ax < xx1)
-            //    continue;
-            //}
-            if (ax >= xx2)
-                  break;
-            
-            // Added by T356. Do not add events which are past the end of the part.
-            //if(event.tick() >= curPart->lenTick())
-            //  break;
-              
-            int nval = newval;
-            if(type == CTRL_PROGRAM)
-            {
-              if(event.dataB() == CTRL_VAL_UNKNOWN)
-              {
-                //if(lastpv == CTRL_VAL_UNKNOWN)
-                //  lastpv = ctrl->hwVal();
-                
-                if(lastpv == CTRL_VAL_UNKNOWN)
-                {
-                  --nval;
-                  if(song->mtype() == MT_GM)
-                    nval |= 0xffff00;
-                }
-                else  
-                  nval = (lastpv & 0xffff00) | (nval - 1);
-              }
-              else  
-                nval = (event.dataB() & 0xffff00) | (nval - 1);
-            }
-              
-            if (ax == xx1) {
-                  // change event
-                  found = true;
-                  ev->setVal(nval);
-                  if ((event.dataB() != nval)) {
-                        Event newEvent = event.clone();
-                        newEvent.setB(nval);
-                        // Indicate no undo, and do port controller values and clone parts. 
-                        audio->msgChangeEvent(event, newEvent, curPart, false, true, true);
-                        ev->setEvent(newEvent);
-                        song_changed = true;
-                        }
-                  }
-            else if (ax < xx2) {
-                  // delete event
-                  
-                  //printf("CtrlCanvas::newVal delete xx1:%d xx2:%d len:%d\n", xx1, xx2, curPart->lenTick()); 
-                 
-                  // Indicate no undo, and do port controller values and clone parts. 
-                  audio->msgDeleteEvent(event, curPart, false, true, true);
-                  
-                  song_changed = true;
-                  }
-            }
-      if (!found) {
-            // new event
-            int tick = xx1 - curPart->tick();
-            // Do not add events which are past the end of the part.
-            if((unsigned)tick < curPart->lenTick())
-            {
-              Event event(Controller);
-              event.setTick(tick);
-              event.setA(_didx);
-              if(type == CTRL_PROGRAM)
-              {
-                if(lastpv == CTRL_VAL_UNKNOWN)
-                {
-                  if(song->mtype() == MT_GM)
-                    event.setB(0xffff00 | (newval - 1));
-                  else  
-                    event.setB(newval - 1);
-                }
-                else    
-                  event.setB((lastpv & 0xffff00) | (newval - 1));
-              }
-              else  
-                event.setB(newval);
-              
-              //printf("CtrlCanvas::newVal add tick:%d A:%d B:%d\n", tick, event.dataA(), event.dataB()); 
-              
-              // Indicate no undo, and do port controller values and clone parts. 
-              audio->msgAddEvent(event, curPart, false, true, true);
-              
-              song_changed = true;
-            }  
-          }
-      if (song_changed) 
-      {
-            songChanged(0);
-            return;
-      }
-      redraw();
-      }
-*/
-
 //---------------------------------------------------------
 //   newVal
 //---------------------------------------------------------
@@ -1607,10 +1294,7 @@ void CtrlCanvas::newVal(int x1, int y)
             }  
       }
       
-      //if(do_selchanged)
-      //  song->update(SC_SELECTION);      // Let songChanged handle the redraw upon SC_SELECTION.
-      //else 
-      if(do_redraw)                 //
+      if(do_redraw)                 // Let songChanged handle the redraw upon SC_SELECTION.
         redraw();
       }
 
@@ -1637,12 +1321,8 @@ void CtrlCanvas::newVal(int x1, int y1, int x2, int y2)
       // So I draw from the first x. (TODO The idea may work now since I wrote this - more work was done.) p4.0.18 Tim.
       
       int xx1 = editor->rasterVal1(x1);
-      // Grab the 'second' raster. Nudge by +1 and let rasterVal2 snap to the next raster.
-      //int xn1 = editor->rasterVal2(xx1 + 1);
       
       int xx2 = editor->rasterVal2(x2);
-      // Grab the 'second last' raster. Nudge by -1 and let rasterVal1 snap to the previous raster.
-      //int xn2 = editor->rasterVal1(xx2 - 1);
       
       // If x1 and x2 happen to lie directly on the same raster, xx1 will equal xx2, 
       //  which is not good - there should always be a spread. Nudge by +1 and recompute.
@@ -1661,7 +1341,6 @@ void CtrlCanvas::newVal(int x1, int y1, int x2, int y2)
       }  
 
       bool do_redraw = false;
-      //bool do_selchanged = false;
       
       // delete existing events
 
@@ -1671,7 +1350,6 @@ void CtrlCanvas::newVal(int x1, int y1, int x2, int y2)
       bool curPartFound = false;
       int lastpv = CTRL_VAL_UNKNOWN;
       int partTick = curPart->tick();
-      //for (ciCEvent i = items.begin(); i != items.end(); ++i) 
       for (iCEvent i = items.begin(); i != items.end() ; ) 
       {
             CEvent* ev = *i;
@@ -1701,10 +1379,7 @@ void CtrlCanvas::newVal(int x1, int y1, int x2, int y2)
             //printf("CtrlCanvas::newVal x:%d xx1:%d xx2:%d len:%d\n", x, xx1, xx2, curPart->lenTick());
             
             if (x < xx1)
-            //if (x < (xn1 >= xx2 ? xx1 : xn1))
             {
-            //  if(event.dataB() != CTRL_VAL_UNKNOWN)
-            //    lastpv = event.dataB();
               prev_ev = i;
               ++i;
               continue;
@@ -1739,24 +1414,14 @@ void CtrlCanvas::newVal(int x1, int y1, int x2, int y2)
             }
             
             do_redraw = true;    // Let songChanged handle the redraw upon SC_SELECTION.
-            //do_selchanged = true;  //
             
             prev_ev = i;
       }
 
-      //if(type == CTRL_PROGRAM && lastpv == CTRL_VAL_UNKNOWN)
       if(ctrl)  
         lastpv = ctrl->hwVal();
         
       // insert new events
-      //for (int x = xx1; x < xx2; x += raster) {
-      // Nudge x by +1 and let rasterVal2 snap to the next raster.
-      //for (int x = xx1; x < xx2;  x = useRaster ? x + raster : editor->rasterVal2(x + 1))    
-      //for (int x = xn1; x < xx2;  x = useRaster ? x + raster : editor->rasterVal2(x + 1))    
-      //for (int x = xn1, step; x < xx2 ; x += (step = useRaster ? raster : editor->rasterVal2(x + 1) - x) )    
-      // Start from the 'second' raster - the first raster is already set in mouseDown!
-      //for (int x = xn1, step; x < xx2 ; x += step )    
-      //for (int x = xn1 >= xx2 ? xx1 : xn1, step; x < xx2 ; x += step )    
       for (int x = xx1, step; x < xx2 ; x += step )    
       {
             step = useRaster ? raster : editor->rasterVal2(x + 1) - x;
@@ -1808,9 +1473,6 @@ void CtrlCanvas::newVal(int x1, int y1, int x2, int y2)
             do_redraw = true;
             }
               
-      //if(do_selchanged)
-      //  song->update(SC_SELECTION);      // Let songChanged handle the redraw upon SC_SELECTION.  
-      //else 
       if(do_redraw)                 //
         redraw();
       }
@@ -1841,10 +1503,8 @@ void CtrlCanvas::deleteVal(int x1, int x2, int)
 
       iCEvent prev_ev = items.end();
       bool curPartFound = false;
-      //bool song_changed = false;
       bool do_redraw = false;
       
-      //for (ciCEvent i = items.begin(); i != items.end(); ++i) 
       for (iCEvent i = items.begin(); i != items.end() ;) 
       {
             CEvent* ev = *i;
@@ -1895,13 +1555,8 @@ void CtrlCanvas::deleteVal(int x1, int x2, int)
             prev_ev = i;
       }
             
-      //if (song_changed) {
-      //      songChanged(0);
-      //      return;
-      //      }
       if(do_redraw)
         redraw();                 // Let songChanged handle the redraw upon SC_SELECTION.  
-        //song->update(SC_SELECTION); //  
       }
 
 //---------------------------------------------------------
diff --git a/muse2/muse/midiedit/dcanvas.cpp b/muse2/muse/midiedit/dcanvas.cpp
index a61b5001..61e98aea 100644
--- a/muse2/muse/midiedit/dcanvas.cpp
+++ b/muse2/muse/midiedit/dcanvas.cpp
@@ -95,7 +95,7 @@ DrumCanvas::DrumCanvas(MidiEditor* pr, QWidget* parent, int sx,
 //   moveCanvasItems
 //---------------------------------------------------------
 
-Undo DrumCanvas::moveCanvasItems(CItemList& items, int dp, int dx, DragType dtype, int* pflags)
+Undo DrumCanvas::moveCanvasItems(CItemList& items, int dp, int dx, DragType dtype)
 {      
   if(editor->parts()->empty())
     return Undo(); //return empty list
@@ -103,7 +103,6 @@ Undo DrumCanvas::moveCanvasItems(CItemList& items, int dp, int dx, DragType dtyp
   PartsToChangeMap parts2change;
   Undo operations;
   
-  int modified = 0;
   for(iPart ip = editor->parts()->begin(); ip != editor->parts()->end(); ++ip)
   {
     Part* part = ip->second;
@@ -159,8 +158,6 @@ Undo DrumCanvas::moveCanvasItems(CItemList& items, int dp, int dx, DragType dtyp
     
     newPart->setLenTick(newPart->lenTick() + diff);
     
-    modified = SC_PART_MODIFIED;
-    
     // BUG FIX: #1650953
     // Added by T356.
     // Fixes posted "select and drag past end of part - crashing" bug
@@ -229,9 +226,6 @@ Undo DrumCanvas::moveCanvasItems(CItemList& items, int dp, int dx, DragType dtyp
           selectItem(ci, false);
   }  
       
-  if(pflags)
-    *pflags = modified;
-  
   return operations;
 }
       
@@ -818,13 +812,6 @@ void DrumCanvas::keyReleased(int index, bool)
 
 void DrumCanvas::mapChanged(int spitch, int dpitch)
       {
-      //TODO: Circumvent undo behaviour, since this isn't really a true change of the events,
-      // but merely a change in pitch because the pitch relates to the order of the dlist.
-      // Right now the sequencer spits out internalError: undoOp without startUndo() if start/stopundo is there, which is misleading
-      // If start/stopundo is there, undo misbehaves since it doesn't undo but messes things up
-      // Other solution: implement a specific undo-event for this (SC_DRUMMAP_MODIFIED or something) which undoes movement of
-      // dlist-items (ml)
-      
       Undo operations;
       std::vector< std::pair<Part*, Event*> > delete_events;
       std::vector< std::pair<Part*, Event> > add_events;
@@ -900,8 +887,8 @@ void DrumCanvas::mapChanged(int spitch, int dpitch)
             operations.push_back(UndoOp(UndoOp::AddEvent, theEvent, thePart, true, false));
             }
       
-      song->applyOperationGroup(operations);
-      song->update(SC_DRUMMAP);
+      song->applyOperationGroup(operations, false); // do not indicate undo
+      song->update(SC_DRUMMAP); //this update is neccessary, as it's not handled by applyOperationGroup()
       }
 
 //---------------------------------------------------------
diff --git a/muse2/muse/midiedit/dcanvas.h b/muse2/muse/midiedit/dcanvas.h
index 748dd74f..cc3b8fff 100644
--- a/muse2/muse/midiedit/dcanvas.h
+++ b/muse2/muse/midiedit/dcanvas.h
@@ -50,7 +50,7 @@ class DrumCanvas : public EventCanvas {
       virtual void drawItem(QPainter&, const CItem*, const QRect&);
       void drawTopItem(QPainter& p, const QRect& rect);
       virtual void drawMoving(QPainter&, const CItem*, const QRect&);
-      virtual Undo moveCanvasItems(CItemList&, int, int, DragType, int*);
+      virtual Undo moveCanvasItems(CItemList&, int, int, DragType);
       virtual UndoOp moveItem(CItem*, const QPoint&, DragType);
       virtual CItem* newItem(const QPoint&, int);
       virtual void resizeItem(CItem*, bool);
diff --git a/muse2/muse/midiedit/ecanvas.cpp b/muse2/muse/midiedit/ecanvas.cpp
index e084c212..9ce84147 100644
--- a/muse2/muse/midiedit/ecanvas.cpp
+++ b/muse2/muse/midiedit/ecanvas.cpp
@@ -101,16 +101,6 @@ QPoint EventCanvas::raster(const QPoint& p) const
       }
 
 //---------------------------------------------------------
-//   update
-//---------------------------------------------------------
-
-void EventCanvas::updateSong(DragType dtype, int flags)
-      {
-      song->update(flags | ((dtype == MOVE_COPY || dtype == MOVE_CLONE)
-         ? SC_EVENT_INSERTED : SC_EVENT_MODIFIED));
-      }
-
-//---------------------------------------------------------
 //   mouseMove
 //---------------------------------------------------------
 
@@ -465,7 +455,7 @@ void EventCanvas::pasteAt(const QString& pt, int pos)
                         return;
                   case Xml::TagStart:
                         if (tag == "eventlist") {
-                              song->startUndo();
+                              Undo operations;
                               EventList* el = new EventList();
                               el->read(xml, "eventlist", true);
                               int modified = SC_EVENT_INSERTED;
@@ -474,7 +464,6 @@ void EventCanvas::pasteAt(const QString& pt, int pos)
                                     int tick = e.tick() + pos - curPart->tick();
                                     if (tick<0) {
                                             printf("ERROR: trying to add event before current part!\n");
-                                            song->endUndo(SC_EVENT_INSERTED);
                                             delete el;
                                             return;
                                             }
@@ -484,15 +473,15 @@ void EventCanvas::pasteAt(const QString& pt, int pos)
                                     if (diff > 0)  {// too short part? extend it
                                             Part* newPart = curPart->clone();
                                             newPart->setLenTick(newPart->lenTick()+diff);
-                                            // Indicate no undo, and do port controller values but not clone parts. 
-                                            audio->msgChangePart(curPart, newPart, false, true, false);
+                                            // Do port controller values but not clone parts. 
+                                            operations.push_back(UndoOp(UndoOp::ModifyPart, curPart, newPart, true, false));
                                             modified=modified|SC_PART_MODIFIED;
                                             curPart = newPart; // reassign
                                             }
-                                    // Indicate no undo, and do not do port controller values and clone parts. 
-                                    audio->msgAddEvent(e, curPart, false, false, false);
+                                    // Do not do port controller values and clone parts. 
+                                    operations.push_back(UndoOp(UndoOp::AddEvent, e, curPart, false, false));
                                     }
-                              song->endUndo(modified);
+                              song->applyOperationGroup(operations);
                               delete el;
                               return;
                               }
@@ -556,11 +545,8 @@ void EventCanvas::endMoveItems(const QPoint& pos, DragType dragtype, int dir)
       
       
       
-      int modified = 0;
-      
-      Undo operations = moveCanvasItems(moving, dp, dx, dragtype, &modified);
+      Undo operations = moveCanvasItems(moving, dp, dx, dragtype);
       song->applyOperationGroup(operations);
-      updateSong(dragtype, modified);
       
       moving.clear();
       updateSelection();
diff --git a/muse2/muse/midiedit/ecanvas.h b/muse2/muse/midiedit/ecanvas.h
index 23875598..b3275607 100644
--- a/muse2/muse/midiedit/ecanvas.h
+++ b/muse2/muse/midiedit/ecanvas.h
@@ -53,10 +53,9 @@ class EventCanvas : public Canvas {
       virtual void addItem(Part*, Event&) = 0;
       // Added by T356.
       virtual QPoint raster(const QPoint&) const;
-      virtual Undo moveCanvasItems(CItemList&, int, int, DragType, int*) = 0;
+      virtual Undo moveCanvasItems(CItemList&, int, int, DragType) = 0;
       virtual UndoOp moveItem(CItem*, const QPoint&, DragType) = 0;
       virtual void endMoveItems(const QPoint&, DragType, int dir);
-      virtual void updateSong(DragType, int flags = 0);
 
    public slots:
       void redrawGrid()       { redraw(); }
diff --git a/muse2/muse/midiedit/prcanvas.cpp b/muse2/muse/midiedit/prcanvas.cpp
index 6845bd12..05fe8252 100644
--- a/muse2/muse/midiedit/prcanvas.cpp
+++ b/muse2/muse/midiedit/prcanvas.cpp
@@ -258,7 +258,7 @@ void PianoCanvas::viewMouseDoubleClickEvent(QMouseEvent* event)
 //   moveCanvasItems
 //---------------------------------------------------------
 
-Undo PianoCanvas::moveCanvasItems(CItemList& items, int dp, int dx, DragType dtype, int* pflags)
+Undo PianoCanvas::moveCanvasItems(CItemList& items, int dp, int dx, DragType dtype)
 {      
   if(editor->parts()->empty())
     return Undo(); //return empty list
@@ -266,7 +266,6 @@ Undo PianoCanvas::moveCanvasItems(CItemList& items, int dp, int dx, DragType dty
   Undo operations;  
   PartsToChangeMap parts2change;
   
-  int modified = 0;
   for(iPart ip = editor->parts()->begin(); ip != editor->parts()->end(); ++ip)
   {
     Part* part = ip->second;
@@ -322,8 +321,6 @@ Undo PianoCanvas::moveCanvasItems(CItemList& items, int dp, int dx, DragType dty
     
     newPart->setLenTick(newPart->lenTick() + diff);
     
-    modified = SC_PART_MODIFIED;
-    
     // BUG FIX: #1650953
     // Added by T356.
     // Fixes posted "select and drag past end of part - crashing" bug
@@ -392,9 +389,6 @@ Undo PianoCanvas::moveCanvasItems(CItemList& items, int dp, int dx, DragType dty
           selectItem(ci, false);
   }  
       
-  if(pflags)
-    *pflags = modified;
-   
   return operations;
 }
       
diff --git a/muse2/muse/midiedit/prcanvas.h b/muse2/muse/midiedit/prcanvas.h
index 94827354..7c77b229 100644
--- a/muse2/muse/midiedit/prcanvas.h
+++ b/muse2/muse/midiedit/prcanvas.h
@@ -49,7 +49,7 @@ class PianoCanvas : public EventCanvas {
       virtual void drawItem(QPainter&, const CItem*, const QRect&);
       void drawTopItem(QPainter &p, const QRect &rect);
       virtual void drawMoving(QPainter&, const CItem*, const QRect&);
-      virtual Undo moveCanvasItems(CItemList&, int, int, DragType, int*);
+      virtual Undo moveCanvasItems(CItemList&, int, int, DragType);
       virtual UndoOp moveItem(CItem*, const QPoint&, DragType);
       virtual CItem* newItem(const QPoint&, int);
       virtual void resizeItem(CItem*, bool noSnap);
diff --git a/muse2/muse/midiedit/scoreedit.cpp b/muse2/muse/midiedit/scoreedit.cpp
index b60b6dbd..7f7382f4 100644
--- a/muse2/muse/midiedit/scoreedit.cpp
+++ b/muse2/muse/midiedit/scoreedit.cpp
@@ -4221,12 +4221,6 @@ void staff_t::apply_lasso(QRect rect, set<Event*>& already_processed)
  *   o rename stuff: UndoOp -> Operation, Undo -> OpList,
  *                   UndoType -> OpType, iUndoOp, riUndoOp -> iOperation,
  *                   undo.cpp/.h -> operations.cpp/.h
- *   o resizing a part is slow, because events get erased
- *   o drag'n'drop in canvases is slow
- *   o drawing controller lines is slow
- *   o cut,copy'n'paste is slow
- *   o reordering drum list is dead slow
- *   o reordering drum list creates unneccessary, actually wrong undo entry
  * 
  * 
  *   o drum list: scroll while dragging
@@ -4241,8 +4235,6 @@ void staff_t::apply_lasso(QRect rect, set<Event*>& already_processed)
  *   o legato: extend length to next note
  *   o delete: add velo and len threshold
  *   o thin out: remove unneeded ctrl messages
- *   o in drum roll: changing the list causes undo to be triggered, WTF?
- *   o changing list is dead slow
  *
  * less important stuff
  *   o controller view in score editor
diff --git a/muse2/muse/part.cpp b/muse2/muse/part.cpp
index c9459c1f..231b947b 100644
--- a/muse2/muse/part.cpp
+++ b/muse2/muse/part.cpp
@@ -833,7 +833,7 @@ void Song::cmdResizePart(Track* track, Part* oPart, unsigned int len)
                   // -   0 or more events are beginning after the new final position. Those are removed from the part
                   // -   The last event begins before new final position and ends after it. If so, it will be resized to end at new part length
                   if (new_partlength < oPart->lenFrame()) {
-                        startUndo();
+                        Undo operations;
 
                         for (iEvent i = el->begin(); i != el->end(); i++) {
                               Event e = i->second;
@@ -843,31 +843,30 @@ void Song::cmdResizePart(Track* track, Part* oPart, unsigned int len)
                               if (event_endframe < new_partlength)
                                     continue;
                               if (event_startframe > new_partlength) { // If event start was after the new length, remove it from part
-                                    // Indicate no undo, and do not do port controller values and clone parts. 
-                                    //audio->msgDeleteEvent(e, nPart, false);
-                                    audio->msgDeleteEvent(e, nPart, false, false, false);
+                                    // Do not do port controller values and clone parts. 
+                                    operations.push_back(UndoOp(UndoOp::DeleteEvent, e, nPart, false, false));
                                     continue;
                                     }
                               if (event_endframe > new_partlength) { // If this event starts before new length and ends after, shrink it
                                     Event newEvent = e.clone();
                                     newEvent.setLenFrame(new_partlength - event_startframe);
-                                    // Indicate no undo, and do not do port controller values and clone parts. 
-                                    //audio->msgChangeEvent(e, newEvent, nPart, false);
+                                    // Do not do port controller values and clone parts. 
                                     audio->msgChangeEvent(e, newEvent, nPart, false, false, false);
+                                    operations.push_back(UndoOp(UndoOp::ModifyEvent, newEvent, e, nPart, false,false));
                                     }
                               }
                         nPart->setLenFrame(new_partlength);
-                        // Indicate no undo, and do not do port controller values and clone parts. 
-                        //audio->msgChangePart(oPart, nPart, false);
-                        audio->msgChangePart(oPart, nPart, false, false, false);
+                        // Do not do port controller values and clone parts. 
+                        operations.push_back(UndoOp(UndoOp::ModifyPart, oPart, nPart, false, false));
 
-                        endUndo(SC_PART_MODIFIED);
+                        song->applyOperationGroup(operations);
                         }
                   // If the part is expanded there can be no additional events beginning after the previous final position
                   // since those are removed if the part has been shrunk at some time (see above)
                   // The only thing we need to check is the final event: If it has data after the previous final position,
                   // we'll expand that event
                   else {
+                        Undo operations;
                         if(!el->empty())
                         {
                           iEvent i = el->end();
@@ -887,33 +886,27 @@ void Song::cmdResizePart(Track* track, Part* oPart, unsigned int len)
                                 new_eventlength = clipframes;
   
                           newEvent.setLenFrame(new_eventlength);
-                          startUndo();
-                          // Indicate no undo, and do not do port controller values and clone parts. 
-                          //audio->msgChangeEvent(last, newEvent, nPart, false);
-                          audio->msgChangeEvent(last, newEvent, nPart, false, false, false);
-                        }  
-                        else
-                        {
-                          startUndo();
+                          // Do not do port controller values and clone parts. 
+                          operations.push_back(UndoOp(UndoOp::ModifyEvent, newEvent, last, nPart, false, false));
                         }  
                         
                         nPart->setLenFrame(new_partlength);
-                        // Indicate no undo, and do not do port controller values and clone parts. 
-                        //audio->msgChangePart(oPart, nPart, false);
+                        // Do not do port controller values and clone parts. 
                         audio->msgChangePart(oPart, nPart, false, false, false);
-                        endUndo(SC_PART_MODIFIED);
+                        operations.push_back(UndoOp(UndoOp::ModifyPart, oPart, nPart, false, false));
+                        song->applyOperationGroup(operations);
                         }
                   }
                   break;
             case Track::MIDI:
             case Track::DRUM:
                   {
-                  startUndo();
+                  Undo operations;
 
                   MidiPart* nPart = new MidiPart(*(MidiPart*)oPart);
                   nPart->setLenTick(len);
-                  // Indicate no undo, and do port controller values but not clone parts. 
-                  audio->msgChangePart(oPart, nPart, false, true, false);
+                  // Do port controller values but not clone parts. 
+                  operations.push_back(UndoOp(UndoOp::ModifyPart, oPart, nPart, true, false));
 
                   // cut Events in nPart
                   // Changed by T356. Don't delete events if this is a clone part.
@@ -926,14 +919,13 @@ void Song::cmdResizePart(Track* track, Part* oPart, unsigned int len)
                           for (; ie != el->end();) {
                                 iEvent i = ie;
                                 ++ie;
-                                // Indicate no undo, and do port controller values and clone parts. 
-                                audio->msgDeleteEvent(i->second, nPart, false, true, true); //FINDMICH
+                                // Do port controller values and clone parts. 
+                                operations.push_back(UndoOp(UndoOp::DeleteEvent, i->second, nPart, true, true));
                                 }
                           }
                   }        
                   
-                  
-                  endUndo(SC_PART_MODIFIED);
+                  song->applyOperationGroup(operations);
                   break;
                   }
             default:
diff --git a/muse2/muse/song.h b/muse2/muse/song.h
index cb9d0f9d..17d70833 100644
--- a/muse2/muse/song.h
+++ b/muse2/muse/song.h
@@ -147,7 +147,7 @@ class Song : public QObject {
       Song(const char* name = 0);
       ~Song();
 
-      void applyOperationGroup(Undo& group);
+      void applyOperationGroup(Undo& group, bool doUndo=true);
 
       void putEvent(int pv);
       void endMsgCmd();
diff --git a/muse2/muse/undo.cpp b/muse2/muse/undo.cpp
index 2b90e26f..2a11c3dc 100644
--- a/muse2/muse/undo.cpp
+++ b/muse2/muse/undo.cpp
@@ -14,6 +14,8 @@
 #include "song.h"
 #include "globals.h"
 
+#include <QAction>
+
 // iundo points to last Undo() in Undo-list
 
 static bool undoMode = false;  // for debugging
@@ -201,12 +203,21 @@ void Song::endUndo(int flags)
       }
 
 
-void Song::applyOperationGroup(Undo& group)
+void Song::applyOperationGroup(Undo& group, bool doUndo)
+{
+      if (!group.empty())
       {
-      //this is a HACK! but it works :)    (added by flo93)
-      redoList->push_back(group);
-      redo();
+            //this is a HACK! but it works :)    (added by flo93)
+            redoList->push_back(group);
+            redo();
+            
+            if (!doUndo)
+            {
+                  undoList->pop_back();
+                  undoAction->setEnabled(!undoList->empty());
+            }
       }
+}
 
 
 
diff --git a/muse2/muse/widgets/canvas.h b/muse2/muse/widgets/canvas.h
index 5037bf37..2eae3d03 100644
--- a/muse2/muse/widgets/canvas.h
+++ b/muse2/muse/widgets/canvas.h
@@ -105,7 +105,6 @@ class Canvas : public View {
       virtual void resizeItem(CItem*, bool noSnap=false) = 0;
       virtual void newItem(CItem*, bool noSnap=false) = 0;
       virtual bool deleteItem(CItem*) = 0;
-      virtual void updateSong(DragType, int flags) = 0;
       int getCurrentDrag();
 
       /*!