plugin racks can now hold an unlimited number of plugins

15 files changed, 147 insertions, 203 deletions

diff --git a/muse/ChangeLog b/muse/ChangeLog
index 0aea89c9..d29a75f2 100644
--- a/muse/ChangeLog
+++ b/muse/ChangeLog
@@ -1,3 +1,7 @@
+31.8 (ws)
+      * plugin racks can now hold an unlimited number of plugins
+29.8 (ws)
+      * fixed drawing of y-magnified pianoroll canvas
 28.8 (ws)
       * added simple midi event dump plugin
       * add midi plugin rack to midi port strips
diff --git a/muse/awl/tcanvas.cpp b/muse/awl/tcanvas.cpp
index 8a9d5d0e..eef9c8ee 100644
--- a/muse/awl/tcanvas.cpp
+++ b/muse/awl/tcanvas.cpp
@@ -1241,7 +1241,7 @@ void TimeCanvas::setCornerWidget(QWidget* w)
       0   1   2  3  4  5  6  7  8  9  10
       c-2 c-1 C0 C1 C2 C3 C4 C5 C6 C7 C8 - G8
 
-      Grid über Oktave:
+      Grid üve:
 
            +------------+ ------------------------------
        11  |            |
@@ -1476,11 +1476,11 @@ int TimeCanvas::pitch2y(int pitch) const
       	static int tt[] = {
 	            12, 19, 25, 32, 38, 51, 58, 64, 71, 77, 84, 90
       	      };
-	      y = (75 * keyHeight) - (tt[pitch%12] + (7 * keyHeight) * (pitch/12));
+	      y = (75 * keyHeight) - (tt[pitch % 12] + (7 * keyHeight) * (pitch / 12));
       	if (y < 0)
 	            y = 0;
             }
-      return lrint(y * _ymag) - wpos.y();
+      return lrint(y - wpos.y() / _ymag);
       }
 
 //---------------------------------------------------------
@@ -1541,7 +1541,7 @@ void TimeCanvas::paintPiano(QPainter& p, QRect r)
       p.drawTiledPixmap(QRectF(x, y, qreal(r.width()), h), *octave, offset);
 
       if (curPitch != -1) {
-            int y = pitch2y(curPitch); //  - lrint(wpos.y() / _ymag);
+            int y = pitch2y(curPitch);
             QPixmap* pm;
             switch(curPitch % 12) {
                   case 0:
diff --git a/muse/muse/audiotrack.cpp b/muse/muse/audiotrack.cpp
index 02cd857a..067d5efe 100644
--- a/muse/muse/audiotrack.cpp
+++ b/muse/muse/audiotrack.cpp
@@ -103,19 +103,10 @@ void AudioTrack::addPlugin(PluginI* plugin, int idx)
                         }
                   }
             }
-      if (idx == -1) {
-            idx = 0;
-            for (; idx < 4; ++idx) {
-                  if ((*_efxPipe)[idx] == 0)
-                        break;
-                  }
-            if (idx == 4) {
-                  printf("internal error: too many plugins\n");
-                  return;
-                  }
-            }
+      if (idx == -1)
+            idx = _efxPipe->size();
 
-      efxPipe()->insert(plugin, idx);
+      efxPipe()->insert(idx, plugin);
       if (plugin) {
             int ncontroller = plugin->plugin()->parameter();
             for (int i = 0; i < ncontroller; ++i) {
diff --git a/muse/muse/midiedit/pianoroll.cpp b/muse/muse/midiedit/pianoroll.cpp
index f0ba5c32..b7def4d9 100644
--- a/muse/muse/midiedit/pianoroll.cpp
+++ b/muse/muse/midiedit/pianoroll.cpp
@@ -64,7 +64,7 @@ PianoRoll::PianoRoll(PartList* pl, bool init)
       tcanvas = new PianoCanvas(this);
       QMenuBar* mb = menuBar();
 
-      //---------Menü----------------------------------
+      //---------Menu----------------------------------
       menuEdit->addSeparator();
 
       QAction* a;
diff --git a/muse/muse/midiplugin.cpp b/muse/muse/midiplugin.cpp
index 4787957a..5c230e6c 100644
--- a/muse/muse/midiplugin.cpp
+++ b/muse/muse/midiplugin.cpp
@@ -267,20 +267,8 @@ MidiPlugin* MidiPluginList::find(const QString& /*file*/, const QString& name)
 //---------------------------------------------------------
 
 MidiPipeline::MidiPipeline()
-   : std::vector<MidiPluginI*>()
+   : QList<MidiPluginI*>()
       {
-      for (int i = 0; i < MidiPipelineDepth; ++i)
-            push_back(0);
-      }
-
-//---------------------------------------------------------
-//   insert
-//    give ownership of object plugin to Pipeline
-//---------------------------------------------------------
-
-void MidiPipeline::insert(MidiPluginI* plugin, int index)
-      {
-      (*this)[index] = plugin;
       }
 
 //---------------------------------------------------------
@@ -319,6 +307,7 @@ QString MidiPipeline::name(int idx) const
       return QString("empty");
       }
 
+#if 0
 //---------------------------------------------------------
 //   empty
 //---------------------------------------------------------
@@ -328,6 +317,7 @@ bool MidiPipeline::empty(int idx) const
       MidiPluginI* p = (*this)[idx];
       return p == 0;
       }
+#endif
 
 //---------------------------------------------------------
 //   move
@@ -361,7 +351,7 @@ void MidiPipeline::showGui(int idx, bool flag)
 //   guiVisible
 //---------------------------------------------------------
 
-bool MidiPipeline::guiVisible(int idx)
+bool MidiPipeline::guiVisible(int idx) const
       {
       MidiPluginI* p = (*this)[idx];
       if (p)
@@ -370,6 +360,18 @@ bool MidiPipeline::guiVisible(int idx)
       }
 
 //---------------------------------------------------------
+//   hasGui
+//---------------------------------------------------------
+
+bool MidiPipeline::hasGui(int idx) const
+      {
+      MidiPluginI* p = (*this)[idx];
+      if (p)
+            return p->hasGui();
+      return false;
+      }
+
+//---------------------------------------------------------
 //   apply
 //---------------------------------------------------------
 
diff --git a/muse/muse/midiplugin.h b/muse/muse/midiplugin.h
index 944b395a..dbe8e631 100644
--- a/muse/muse/midiplugin.h
+++ b/muse/muse/midiplugin.h
@@ -72,9 +72,9 @@ class MidiPlugin {
 //   MidiPluginList
 //---------------------------------------------------------
 
-typedef std::list<MidiPlugin*>::iterator iMidiPlugin;
+typedef QList<MidiPlugin*>::iterator iMidiPlugin;
 
-class MidiPluginList : public std::list<MidiPlugin*> {
+class MidiPluginList : public QList<MidiPlugin*> {
    public:
       MidiPlugin* find(const QString&, const QString&);
       MidiPluginList() {}
@@ -115,9 +115,9 @@ class MidiPluginI {
       void showGui();
       void showGui(bool);
       bool hasGui() const { return mempi->hasGui(); }
+      bool guiVisible() const;
       void getInitData(int* len, const unsigned char** p) { mempi->getInitData(len, p); }
       void setInitData(int len, const unsigned char* p)   { mempi->setInitData(len, p); }
-      bool guiVisible() const;
       };
 
 //---------------------------------------------------------
@@ -125,21 +125,17 @@ class MidiPluginI {
 //    chain of connected efx inserts
 //---------------------------------------------------------
 
-const int MidiPipelineDepth = 4;
-
-class MidiPipeline : public std::vector<MidiPluginI*> {
+class MidiPipeline : public QList<MidiPluginI*> {
    public:
       MidiPipeline();
-      void insert(MidiPluginI* p, int index);
       bool isOn(int idx) const;
       void setOn(int, bool);
       QString name(int idx) const;
       void showGui(int, bool);
-      bool guiVisible(int);
+      bool guiVisible(int) const;
+      bool hasGui(int) const;
       void apply(unsigned, unsigned, MPEventList*, MPEventList*);
       void move(int idx, bool up);
-      bool empty(int idx) const;
-      MidiPluginI* plugin(int idx) { return (*this)[idx]; }
       };
 
 typedef MidiPipeline::iterator iMidiPluginI;
@@ -163,6 +159,8 @@ class MidiPluginDialog : public QDialog {
       void fillPlugs();
       };
 
+static const int MidiPipelineDepth = 4;
+
 extern void initMidiPlugins();
 extern MidiPluginList midiPlugins;
 
diff --git a/muse/muse/mixer/midirack.cpp b/muse/muse/mixer/midirack.cpp
index 099e27e2..3e8da952 100644
--- a/muse/muse/mixer/midirack.cpp
+++ b/muse/muse/mixer/midirack.cpp
@@ -13,6 +13,7 @@
 #include "song.h"
 #include "midiplugin.h"
 #include "audio.h"
+#include "muse.h"
 
 //---------------------------------------------------------
 //   MidiRack
@@ -22,19 +23,14 @@ MidiRack::MidiRack(QWidget* parent, MidiTrackBase* t)
    : QListWidget(parent)
       {
       setAttribute(Qt::WA_DeleteOnClose, true);
+      verticalScrollBar()->setStyle(smallStyle);
       track = t;
       setFont(*config.fonts[1]);
 
       setHorizontalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
-      setVerticalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
 
       setSelectionMode(QAbstractItemView::SingleSelection);
-      for (int i = 0; i < MidiPipelineDepth; ++i) {
-            QListWidgetItem* item = new QListWidgetItem;
-            item->setText(t->pipeline()->name(i));
-            item->setBackgroundColor(t->pipeline()->isOn(i) ? Qt::white : Qt::gray);
-            addItem(item);
-            }
+      songChanged(SC_RACK);   // force update
       connect(this, SIGNAL(itemDoubleClicked(QListWidgetItem*)),
          this, SLOT(doubleClicked(QListWidgetItem*)));
       connect(song, SIGNAL(songChanged(int)), SLOT(songChanged(int)));
@@ -59,48 +55,41 @@ QSize MidiRack::sizeHint() const
 void MidiRack::songChanged(int typ)
       {
       if (typ & (SC_ROUTE | SC_RACK)) {
-            for (int i = 0; i < MidiPipelineDepth; ++i) {
-                  QListWidgetItem* it = item(i);
-                  it->setText(track->pipeline()->name(i));
-                  it->setBackgroundColor(track->pipeline()->isOn(i) ? Qt::white : Qt::gray);
+            clear();
+            foreach(MidiPluginI* plugin, *(track->pipeline())) {
+                  QListWidgetItem* item = new QListWidgetItem;
+                  item->setText(plugin->name());
+                  // tooltip should only be set if name does not fit
+                  // (is elided)
+                  item->setToolTip(plugin->name());
+                  item->setBackgroundColor(plugin->on() ? Qt::white : Qt::gray);
+                  addItem(item);
                   }
             }
       }
 
 //---------------------------------------------------------
-//   menuRequested
+//   contextMenuEvent
 //---------------------------------------------------------
 
 void MidiRack::contextMenuEvent(QContextMenuEvent* ev)
       {
       QPoint pt(ev->pos());
       QListWidgetItem* item = itemAt(pt);
+      MidiPipeline* pipe    = track->pipeline();
 
-      if (item == 0 || track == 0)
-            return;
-
-      int idx = row(item);
-      QString name;
-      bool mute;
-
-      MidiPipeline* pipe = track->pipeline();
-      name  = pipe->name(idx);
-      mute  = pipe->isOn(idx);
-
-      QMenu* menu = new QMenu;
-
-      QAction* upAction = menu->addAction(QIcon(*upIcon), tr("move up"));
-      QAction* downAction = menu->addAction(QIcon(*downIcon), tr("move down"));
+      QMenu* menu           = new QMenu;
+      QAction* upAction     = menu->addAction(QIcon(*upIcon), tr("move up"));
+      QAction* downAction   = menu->addAction(QIcon(*downIcon), tr("move down"));
       QAction* removeAction = menu->addAction(tr("remove"));
       QAction* bypassAction = menu->addAction(tr("bypass"));
       QAction* showAction   = menu->addAction(tr("show gui"));
-      QAction* newAction;
-
-      bypassAction->setChecked(!pipe->isOn(idx));
-      showAction->setChecked(pipe->guiVisible(idx));
+      QAction* newAction    = menu->addAction(tr("new"));
+      bypassAction->setCheckable(true);
+      showAction->setCheckable(true);
 
-      if (pipe->empty(idx)) {
-            newAction = menu->addAction(tr("new"));
+      int idx = -1;
+      if (item == 0) {
             upAction->setEnabled(false);
             downAction->setEnabled(false);
             removeAction->setEnabled(false);
@@ -108,11 +97,13 @@ void MidiRack::contextMenuEvent(QContextMenuEvent* ev)
             showAction->setEnabled(false);
             }
       else {
-            newAction = menu->addAction(tr("change"));
-            if (idx == 0)
-                  upAction->setEnabled(false);
-            if (idx == (MidiPipelineDepth-1))
-                  downAction->setEnabled(false);
+            idx = row(item);
+            upAction->setEnabled(idx != 0);
+            downAction->setEnabled(idx < (pipe->size() - 1));
+            showAction->setEnabled(pipe->hasGui(idx));
+            bypassAction->setEnabled(true);
+            bypassAction->setChecked(!pipe->isOn(idx));
+            showAction->setChecked(pipe->guiVisible(idx));
             }
 
       QAction* sel = menu->exec(mapToGlobal(pt), newAction);
@@ -130,7 +121,7 @@ void MidiRack::contextMenuEvent(QContextMenuEvent* ev)
                         delete plugi;
                         }
                   else
-                        audio->msgAddMidiPlugin(track, idx, plugi);
+                        audio->msgAddMidiPlugin(track, pipe->size(), plugi);
                   }
             }
       else if (sel == removeAction) {
@@ -151,7 +142,7 @@ void MidiRack::contextMenuEvent(QContextMenuEvent* ev)
                   }
             }
       else if (sel == downAction) {
-            if (idx < (MidiPipelineDepth-1)) {
+            if (idx < (pipe->size() - 1)) {
                   setCurrentRow(idx+1);
                   pipe->move(idx, false);
                   }
@@ -172,7 +163,7 @@ void MidiRack::doubleClicked(QListWidgetItem* it)
       int idx = row(it);
       MidiPipeline* pipe = track->pipeline();
 
-      if (!pipe->empty(idx)) {
+      if (!pipe->value(idx)) {
             bool flag = !pipe->guiVisible(idx);
             pipe->showGui(idx, flag);
             }
@@ -190,5 +181,6 @@ void MidiRack::doubleClicked(QListWidgetItem* it)
                         }
                   }
             }
+      song->update(SC_RACK);
       }
 
diff --git a/muse/muse/mixer/rack.cpp b/muse/muse/mixer/rack.cpp
index 609f571f..863a788a 100644
--- a/muse/muse/mixer/rack.cpp
+++ b/muse/muse/mixer/rack.cpp
@@ -6,8 +6,6 @@
 //  (C) Copyright 2000-2003 Werner Schweer (ws@seh.de)
 //=========================================================
 
-//#include <QDrag>
-//#include <QMimeData>
 #include "rack.h"
 #include "song.h"
 #include "audio.h"
@@ -16,6 +14,9 @@
 #include "plugin.h"
 #include "plugingui.h"
 #include "widgets/filedialog.h"
+#include "muse.h"
+
+static const int PipelineDepth = 4;
 
 //---------------------------------------------------------
 //   EffectRack
@@ -25,19 +26,15 @@ EffectRack::EffectRack(QWidget* parent, AudioTrack* t)
    : QListWidget(parent)
       {
       setAttribute(Qt::WA_DeleteOnClose, true);
+      verticalScrollBar()->setStyle(smallStyle);
+
       track = t;
       setFont(*config.fonts[1]);
 
       setHorizontalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
-      setVerticalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
 
       setSelectionMode(QAbstractItemView::SingleSelection);
-      for (int i = 0; i < PipelineDepth; ++i) {
-            QListWidgetItem* item = new QListWidgetItem;
-            item->setText(t->efxPipe()->name(i));
-            item->setBackgroundColor(t->efxPipe()->isOn(i) ? Qt::white : Qt::gray);
-            addItem(item);
-            }
+      songChanged(SC_RACK);   // force update
       connect(this, SIGNAL(itemDoubleClicked(QListWidgetItem*)),
          this, SLOT(doubleClicked(QListWidgetItem*)));
       connect(song, SIGNAL(songChanged(int)), SLOT(songChanged(int)));
@@ -63,10 +60,15 @@ QSize EffectRack::sizeHint() const
 void EffectRack::songChanged(int typ)
       {
       if (typ & (SC_ROUTE | SC_RACK)) {
-            for (int i = 0; i < PipelineDepth; ++i) {
-                  QListWidgetItem* it = item(i);
-                  it->setText(track->efxPipe()->name(i));
-                  it->setBackgroundColor(track->efxPipe()->isOn(i) ? Qt::white : Qt::gray);
+            clear();
+            foreach(PluginI* plugin, *(track->efxPipe())) {
+                  QListWidgetItem* item = new QListWidgetItem;
+                  item->setText(plugin->name());
+                  // tooltip should only be set if name does not fit
+                  // (is elided)
+                  item->setToolTip(plugin->name());
+                  item->setBackgroundColor(plugin->on() ? Qt::white : Qt::gray);
+                  addItem(item);
                   }
             }
       }
@@ -79,40 +81,25 @@ void EffectRack::contextMenuEvent(QContextMenuEvent* ev)
       {
       QPoint pt(ev->pos());
       QListWidgetItem* item = itemAt(pt);
-      if (item == 0 || track == 0)
-            return;
 
-      int idx = row(item);
+      int idx = -1;
       QString name;
-      bool mute;
       Pipeline* pipe = track->efxPipe();
-      if (pipe) {
-            name = pipe->name(idx);
-            mute = pipe->isOn(idx);
-            }
 
-      QAction* newAction;
-      QAction* upAction;
-      QAction* downAction;
-      QAction* removeAction;
-      QAction* bypassAction;
-      QAction* showAction;
-      QAction* showCustomAction;
-
-      QMenu* menu      = new QMenu;
-      upAction         = menu->addAction(QIcon(*upIcon), tr("move up"));
-      downAction       = menu->addAction(QIcon(*downIcon), tr("move down"));
-      removeAction     = menu->addAction(tr("remove"));
-      bypassAction     = menu->addAction(tr("bypass"));
-      showAction       = menu->addAction(tr("show gui"));
-      showCustomAction = menu->addAction(tr("show native gui"));
-
-      bypassAction->setChecked(!pipe->isOn(idx));
-      showAction->setChecked(pipe->guiVisible(idx));
-      showCustomAction->setChecked(pipe->nativeGuiVisible(idx));
-
-      if (pipe->empty(idx)) {
-            newAction = menu->addAction(tr("new"));
+      QMenu* menu               = new QMenu;
+      QAction* upAction         = menu->addAction(QIcon(*upIcon), tr("move up"));
+      QAction* downAction       = menu->addAction(QIcon(*downIcon), tr("move down"));
+      QAction* removeAction     = menu->addAction(tr("remove"));
+      QAction* bypassAction     = menu->addAction(tr("bypass"));
+      QAction* showAction       = menu->addAction(tr("show gui"));
+      QAction* showCustomAction = menu->addAction(tr("show native gui"));
+      QAction* newAction        = menu->addAction(tr("new"));
+
+      bypassAction->setCheckable(true);
+      showAction->setCheckable(true);
+      showCustomAction->setCheckable(true);
+
+      if (!item) {
             upAction->setEnabled(false);
             downAction->setEnabled(false);
             removeAction->setEnabled(false);
@@ -121,12 +108,18 @@ void EffectRack::contextMenuEvent(QContextMenuEvent* ev)
             showCustomAction->setEnabled(false);
             }
       else {
-            newAction = menu->addAction(tr("change"));
-            if (idx == 0)
-                  upAction->setEnabled(false);
-            if (idx == (PipelineDepth-1))
-                  downAction->setEnabled(false);
+            idx = row(item);
+            upAction->setEnabled(idx != 0);
+            downAction->setEnabled(idx < pipe->size()-1);
             showCustomAction->setEnabled(pipe->hasNativeGui(idx));
+
+            bypassAction->setEnabled(true);
+            showAction->setEnabled(true);
+            showCustomAction->setEnabled(true);
+
+            bypassAction->setChecked(!pipe->isOn(idx));
+            showAction->setChecked(pipe->guiVisible(idx));
+            showCustomAction->setChecked(pipe->nativeGuiVisible(idx));
             }
 
       QAction* sel = menu->exec(mapToGlobal(pt), newAction);
@@ -184,13 +177,13 @@ void EffectRack::contextMenuEvent(QContextMenuEvent* ev)
 
 void EffectRack::doubleClicked(QListWidgetItem* it)
       {
-      if (it == 0 || track == 0)
+      if (track == 0)
             return;
-      int idx        = row(it);
-      Pipeline* pipe = track->efxPipe();
 
-      if (!pipe->empty(idx)) {
-            bool flag = !pipe->guiVisible(idx);
+      if (it) {
+            int idx        = row(it);
+            Pipeline* pipe = track->efxPipe();
+            bool flag      = !pipe->guiVisible(idx);
             pipe->showGui(idx, flag);
             }
       else {
@@ -203,7 +196,7 @@ void EffectRack::doubleClicked(QListWidgetItem* it)
                         delete plugi;
                         }
                   else {
-                        audio->msgAddPlugin(track, idx, plugi);
+                        audio->msgAddPlugin(track, -1, plugi);
                         }
                   song->update(SC_RACK);
                   }
diff --git a/muse/muse/muse.cpp b/muse/muse/muse.cpp
index 67832ac9..695fbf98 100644
--- a/muse/muse/muse.cpp
+++ b/muse/muse/muse.cpp
@@ -98,6 +98,8 @@ extern void initDSSI();
 extern bool initJackAudio();
 extern void exitJackAudio();
 
+QStyle* smallStyle;
+
 int watchAudio, watchAudioPrefetch, watchMidi;
 pthread_t splashThread;
 MusE* muse;
@@ -2820,7 +2822,10 @@ int main(int argc, char* argv[])
       gmDrumMap.initGm();    // init default drum map
       readConfiguration();
 
-       QApplication::setFont(*config.fonts[0]);
+      QApplication::setFont(*config.fonts[0]);
+
+      // this style is used for scrollbars in mixer plugin racks:
+      smallStyle = new QWindowsStyle();
 
       // SHOW MUSE SPLASH SCREEN
       if (config.showSplashScreen) {
diff --git a/muse/muse/muse.h b/muse/muse/muse.h
index 36c23ae3..bcd13af9 100644
--- a/muse/muse/muse.h
+++ b/muse/muse/muse.h
@@ -295,6 +295,7 @@ class MusE : public QMainWindow, public Ui::MuseBase
       };
 
 extern MusE* muse;
+extern QStyle* smallStyle;
 
 #endif
 
diff --git a/muse/muse/plugin.cpp b/muse/muse/plugin.cpp
index aeee6cc5..09cdf555 100644
--- a/muse/muse/plugin.cpp
+++ b/muse/muse/plugin.cpp
@@ -236,35 +236,13 @@ Plugin* PluginList::find(const QString& file, const QString& name)
       }
 
 //---------------------------------------------------------
-//   Pipeline
-//---------------------------------------------------------
-
-Pipeline::Pipeline()
-   : std::vector<PluginI*>()
-      {
-      for (int i = 0; i < PipelineDepth; ++i)
-            push_back(0);
-      }
-
-//---------------------------------------------------------
 //   setChannels
 //---------------------------------------------------------
 
 void Pipeline::setChannels(int n)
       {
-      for (int i = 0; i < PipelineDepth; ++i)
-            if ((*this)[i])
-                  (*this)[i]->setChannels(n);
-      }
-
-//---------------------------------------------------------
-//   insert
-//    give ownership of object plugin to Pipeline
-//---------------------------------------------------------
-
-void Pipeline::insert(PluginI* plugin, int index)
-      {
-      (*this)[index] = plugin;
+      foreach(PluginI* plugin, *this)
+            plugin->setChannels(n);
       }
 
 //---------------------------------------------------------
@@ -273,7 +251,7 @@ void Pipeline::insert(PluginI* plugin, int index)
 
 bool Pipeline::isOn(int idx) const
       {
-      PluginI* p = (*this)[idx];
+      PluginI* p = value(idx);
       if (p)
             return p->on();
       return false;
@@ -285,7 +263,7 @@ bool Pipeline::isOn(int idx) const
 
 void Pipeline::setOn(int idx, bool flag)
       {
-      PluginI* p = (*this)[idx];
+      PluginI* p = value(idx);
       if (p) {
             p->setOn(flag);
             if (p->gui())
@@ -299,7 +277,7 @@ void Pipeline::setOn(int idx, bool flag)
 
 QString Pipeline::label(int idx) const
       {
-      PluginI* p = (*this)[idx];
+      PluginI* p = value(idx);
       if (p)
             return p->label();
       return QString("");
@@ -311,7 +289,7 @@ QString Pipeline::label(int idx) const
 
 QString Pipeline::name(int idx) const
       {
-      PluginI* p = (*this)[idx];
+      PluginI* p = value(idx);
       if (p)
             return p->name();
       return QString("empty");
@@ -323,23 +301,13 @@ QString Pipeline::name(int idx) const
 
 bool Pipeline::hasNativeGui(int idx) const
       {
-      PluginI* p = (*this)[idx];
+      PluginI* p = value(idx);
       if (p)
             return p->hasNativeGui();
       return false;
       }
 
 //---------------------------------------------------------
-//   empty
-//---------------------------------------------------------
-
-bool Pipeline::empty(int idx) const
-      {
-      PluginI* p = (*this)[idx];
-      return p == 0;
-      }
-
-//---------------------------------------------------------
 //   move
 //---------------------------------------------------------
 
diff --git a/muse/muse/plugin.h b/muse/muse/plugin.h
index a31db428..08e61f4d 100644
--- a/muse/muse/plugin.h
+++ b/muse/muse/plugin.h
@@ -308,12 +308,12 @@ class PluginI {
 //    chain of connected efx inserts
 //---------------------------------------------------------
 
-const int PipelineDepth = 4;
+// const int PipelineDepth = 4;
 
-class Pipeline : public std::vector<PluginI*> {
+class Pipeline : public QList<PluginI*> {
    public:
-      Pipeline();
-      void insert(PluginI* p, int index);
+      Pipeline() {}
+//      void insert(PluginI* p, int index);
       bool isOn(int idx) const;
       void setOn(int, bool);
       QString label(int idx) const;
@@ -325,9 +325,9 @@ class Pipeline : public std::vector<PluginI*> {
       void showNativeGui(int, bool);
       void apply(int ports, unsigned long nframes, float** buffer);
       void move(int idx, bool up);
-      bool empty(int idx) const;
+//      bool empty(int idx) const;
       void setChannels(int);
-      PluginI* plugin(int idx) { return (*this)[idx]; }
+      PluginI* plugin(int idx) { return value(idx); }
       };
 
 typedef Pipeline::iterator iPluginI;
diff --git a/muse/muse/plugingui.cpp b/muse/muse/plugingui.cpp
index c6b0ffcd..2bc0929f 100644
--- a/muse/muse/plugingui.cpp
+++ b/muse/muse/plugingui.cpp
@@ -660,9 +660,9 @@ void PluginGui::bypassToggled(bool val)
 
 void PluginGui::setOn(bool val)
       {
-      onOff->blockSignals(true);
+//      onOff->blockSignals(true);
       onOff->setChecked(val);
-      onOff->blockSignals(false);
+//      onOff->blockSignals(false);
       }
 
 //---------------------------------------------------------
diff --git a/muse/muse/seqmsg.cpp b/muse/muse/seqmsg.cpp
index 930ed13a..c4e947cc 100644
--- a/muse/muse/seqmsg.cpp
+++ b/muse/muse/seqmsg.cpp
@@ -181,11 +181,7 @@ void Audio::msgAddPlugin(AudioTrack* node, int idx, PluginI* plugin)
       msg.track  = node;
       msg.ival   = idx;
       msg.plugin = plugin;
-      PluginI* oldPlugin = node->plugin(idx);
       sendMsg(&msg);
-      if (oldPlugin) {
-            delete oldPlugin;
-            }
       }
 
 //---------------------------------------------------------
diff --git a/muse/muse/track.cpp b/muse/muse/track.cpp
index 6c011d5e..a12890b9 100644
--- a/muse/muse/track.cpp
+++ b/muse/muse/track.cpp
@@ -769,13 +769,13 @@ bool MidiTrackBase::readProperties(QDomNode node)
 
 MidiPluginI* MidiTrackBase::plugin(int idx) const
       {
-      return (*_pipeline)[idx];
+      return _pipeline->value(idx);
       }
 
-
 //---------------------------------------------------------
 //   addPlugin
-//    idx = -1   insert into first free slot
+//    idx = -1     append
+//    plugin = 0   remove slot
 //---------------------------------------------------------
 
 void MidiTrackBase::addPlugin(MidiPluginI* plugin, int idx)
@@ -792,20 +792,11 @@ void MidiTrackBase::addPlugin(MidiPluginI* plugin, int idx)
                   }
 #endif
             }
-      if (idx == -1) {
-            idx = 0;
-            for (; idx < 4; ++idx) {
-                  if ((*_pipeline)[idx] == 0)
-                        break;
-                  }
-            if (idx == 4) {
-                  printf("internal error: too many plugins\n");
-                  return;
-                  }
-            }
+      if (idx == -1)
+            idx = _pipeline->size();
 
-      _pipeline->insert(plugin, idx);
       if (plugin) {
+            _pipeline->insert(idx, plugin);
 #if 0
             int ncontroller = plugin->plugin()->parameter();
             for (int i = 0; i < ncontroller; ++i) {
@@ -827,6 +818,9 @@ void MidiTrackBase::addPlugin(MidiPluginI* plugin, int idx)
                   }
 #endif
             }
+      else {
+            _pipeline->removeAt(idx);
+            }
       }