fix (?) behaviour when punching into automation write mode while the transport is...
[ardour.git] / libs / evoral / src / ControlList.cpp
index b7171907682d6aea1b25e96f34b02ffbea4ee7e4..a095daa13527e9f25e6dbbaf3076495d39adfa63 100644 (file)
@@ -1,5 +1,5 @@
 /* This file is part of Evoral.
- * Copyright (C) 2008 Dave Robillard <http://drobilla.net>
+ * Copyright (C) 2008 David Robillard <http://drobilla.net>
  * Copyright (C) 2000-2008 Paul Davis
  *
  * Evoral is free software; you can redistribute it and/or modify it under the
 #include "evoral/ControlList.hpp"
 #include "evoral/Curve.hpp"
 
+#include "pbd/compose.h"
+
 using namespace std;
+using namespace PBD;
 
 namespace Evoral {
 
-
 inline bool event_time_less_than (ControlEvent* a, ControlEvent* b)
 {
        return a->when < b->when;
 }
 
+/* this has no units but corresponds to the area of a rectangle
+   computed between three points in the list. If the area is
+   large, it indicates significant non-linearity between the
+   points. 
+
+   during automation recording we thin the recorded points
+   using this value. if a point is sufficiently co-linear 
+   with its neighbours (as defined by the area of the rectangle
+   formed by three of them), we will not include it in the
+   ControlList. a smaller value will exclude less points,
+   a larger value will exclude more points, so it effectively
+   measures the amount of thinning to be done.
+*/
+
+double ControlList::_thinning_factor = 20.0; 
 
 ControlList::ControlList (const Parameter& id)
        : _parameter(id)
@@ -43,13 +60,17 @@ ControlList::ControlList (const Parameter& id)
        _changed_when_thawed = false;
        _min_yval = id.min();
        _max_yval = id.max();
-       _max_xval = 0; // means "no limit"
-       _default_value = 0;
+       _default_value = id.normal();
        _lookup_cache.left = -1;
        _lookup_cache.range.first = _events.end();
        _search_cache.left = -1;
        _search_cache.first = _events.end();
        _sort_pending = false;
+       new_write_pass = true;
+       _in_write_pass = false;
+       did_write_during_pass = false;
+       insert_position = -1;
+       most_recent_insert_iterator = _events.end();
 }
 
 ControlList::ControlList (const ControlList& other)
@@ -61,15 +82,17 @@ ControlList::ControlList (const ControlList& other)
        _changed_when_thawed = false;
        _min_yval = other._min_yval;
        _max_yval = other._max_yval;
-       _max_xval = other._max_xval;
        _default_value = other._default_value;
        _lookup_cache.range.first = _events.end();
        _search_cache.first = _events.end();
        _sort_pending = false;
+       new_write_pass = true;
+       _in_write_pass = false;
+       did_write_during_pass = false;
+       insert_position = -1;
+       most_recent_insert_iterator = _events.end();
 
-       for (const_iterator i = other._events.begin(); i != other._events.end(); ++i) {
-               _events.push_back (new ControlEvent (**i));
-       }
+       copy_events (other);
 
        mark_dirty ();
 }
@@ -83,7 +106,6 @@ ControlList::ControlList (const ControlList& other, double start, double end)
        _changed_when_thawed = false;
        _min_yval = other._min_yval;
        _max_yval = other._max_yval;
-       _max_xval = other._max_xval;
        _default_value = other._default_value;
        _lookup_cache.range.first = _events.end();
        _search_cache.first = _events.end();
@@ -94,11 +116,15 @@ ControlList::ControlList (const ControlList& other, double start, double end)
        boost::shared_ptr<ControlList> section = const_cast<ControlList*>(&other)->copy (start, end);
 
        if (!section->empty()) {
-               for (iterator i = section->begin(); i != section->end(); ++i) {
-                       _events.push_back (new ControlEvent ((*i)->when, (*i)->value));
-               }
+               copy_events (*(section.get()));
        }
 
+       new_write_pass = false;
+       _in_write_pass = false;
+       did_write_during_pass = false;
+       insert_position = -1;
+       most_recent_insert_iterator = _events.end();
+
        mark_dirty ();
 }
 
@@ -107,13 +133,6 @@ ControlList::~ControlList()
        for (EventList::iterator x = _events.begin(); x != _events.end(); ++x) {
                delete (*x);
        }
-        
-       for (list<NascentInfo*>::iterator n = nascent.begin(); n != nascent.end(); ++n) {
-                for (EventList::iterator x = (*n)->events.begin(); x != (*n)->events.end(); ++x) {
-                        delete *x;
-                }
-               delete (*n);
-       }
 
        delete _curve;
 }
@@ -135,24 +154,31 @@ ControlList::operator= (const ControlList& other)
 {
        if (this != &other) {
 
-               _events.clear ();
-
-               for (const_iterator i = other._events.begin(); i != other._events.end(); ++i) {
-                       _events.push_back (new ControlEvent (**i));
-               }
-
                _min_yval = other._min_yval;
                _max_yval = other._max_yval;
-               _max_xval = other._max_xval;
                _default_value = other._default_value;
-
-               mark_dirty ();
-               maybe_signal_changed ();
+               
+               copy_events (other);
        }
 
        return *this;
 }
 
+void
+ControlList::copy_events (const ControlList& other)
+{
+       {
+               Glib::Threads::Mutex::Lock lm (_lock);
+               _events.clear ();
+               for (const_iterator i = other.begin(); i != other.end(); ++i) {
+                       _events.push_back (new ControlEvent ((*i)->when, (*i)->value));
+               }
+               unlocked_invalidate_insert_iterator ();
+               mark_dirty ();
+       }
+       maybe_signal_changed ();
+}
+
 void
 ControlList::create_curve()
 {
@@ -180,8 +206,9 @@ void
 ControlList::clear ()
 {
        {
-               Glib::Mutex::Lock lm (_lock);
+               Glib::Threads::Mutex::Lock lm (_lock);
                _events.clear ();
+               unlocked_invalidate_insert_iterator ();
                mark_dirty ();
        }
 
@@ -191,14 +218,14 @@ ControlList::clear ()
 void
 ControlList::x_scale (double factor)
 {
-       Glib::Mutex::Lock lm (_lock);
+       Glib::Threads::Mutex::Lock lm (_lock);
        _x_scale (factor);
 }
 
 bool
 ControlList::extend_to (double when)
 {
-       Glib::Mutex::Lock lm (_lock);
+       Glib::Threads::Mutex::Lock lm (_lock);
        if (_events.empty() || _events.back()->when == when) {
                return false;
        }
@@ -207,218 +234,431 @@ ControlList::extend_to (double when)
        return true;
 }
 
-void 
+void
 ControlList::_x_scale (double factor)
 {
        for (iterator i = _events.begin(); i != _events.end(); ++i) {
-               (*i)->when = floor ((*i)->when * factor);
+               (*i)->when *= factor;
        }
 
        mark_dirty ();
 }
 
+struct ControlEventTimeComparator {
+       bool operator() (ControlEvent* a, ControlEvent* b) {
+               return a->when < b->when;
+       }
+};
+
 void
-ControlList::write_pass_finished (double when)
+ControlList::thin ()
 {
-        merge_nascent (when);
+       bool changed = false;
+
+       {
+               Glib::Threads::Mutex::Lock lm (_lock);
+               
+               ControlEvent* prevprev = 0;
+               ControlEvent* cur = 0;
+               ControlEvent* prev = 0;
+               iterator pprev;
+               int counter = 0;
+               
+               DEBUG_TRACE (DEBUG::ControlList, string_compose ("@%1 thin from %2 events\n", this, _events.size()));
+               
+               for (iterator i = _events.begin(); i != _events.end(); ++i) {
+                       
+                       cur = *i;
+                       counter++;
+                       
+                       if (counter > 2) {
+                               
+                               /* compute the area of the triangle formed by 3 points
+                                */
+                               
+                               double area = fabs ((prevprev->when * (prev->value - cur->value)) + 
+                                                   (prev->when * (cur->value - prevprev->value)) + 
+                                                   (cur->when * (prevprev->value - prev->value)));
+                               
+                               if (area < _thinning_factor) {
+                                       iterator tmp = pprev;
+                                       
+                                       /* pprev will change to current
+                                          i is incremented to the next event
+                                          as we loop.
+                                       */
+                                       
+                                       pprev = i;
+                                       _events.erase (tmp);
+                                       changed = true;
+                                       continue;
+                               }
+                       }
+                       
+                       prevprev = prev;
+                       prev = cur;
+                       pprev = i;
+               }
+               
+               DEBUG_TRACE (DEBUG::ControlList, string_compose ("@%1 thin => %2 events\n", this, _events.size()));
+
+               if (changed) {
+                       unlocked_invalidate_insert_iterator ();
+                       mark_dirty ();
+               }
+       }
+
+       if (changed) {
+               maybe_signal_changed ();
+       }
 }
 
 void
-ControlList::merge_nascent (double when)
+ControlList::fast_simple_add (double when, double value)
 {
-        {
-                Glib::Mutex::Lock lm (_lock);
-
-                if (nascent.empty()) {
-                        return;
-                }
-
-                for (list<NascentInfo*>::iterator n = nascent.begin(); n != nascent.end(); ++n) {
-
-                        NascentInfo* ninfo = *n;
-                        EventList& nascent_events (ninfo->events);
-                        bool need_adjacent_start_clamp;
-                        bool need_adjacent_end_clamp;
-
-                        if (nascent_events.empty()) {
-                                delete ninfo;
-                                continue;
-                        }
-                        
-                        if (ninfo->start_time < 0.0) {
-                                ninfo->start_time = nascent_events.front()->when;
-                        }
-                        
-                        if (ninfo->end_time < 0.0) {
-                                ninfo->end_time = when;
-                        }
-
-                        bool preexisting = !_events.empty();
-
-                        if (!preexisting) {
-                                
-                                _events = nascent_events;
-                                
-                        } else if (ninfo->end_time < _events.front()->when) {
-                                
-                                /* all points in nascent are before the first existing point */
-
-                                _events.insert (_events.begin(), nascent_events.begin(), nascent_events.end());
-                                
-                        } else if (ninfo->start_time > _events.back()->when) {
-                                
-                                /* all points in nascent are after the last existing point */
-
-                                _events.insert (_events.end(), nascent_events.begin(), nascent_events.end());
-                                
-                        } else {
-                                
-                                /* find the range that overaps with nascent events,
-                                   and insert the contents of nascent events.
-                                */
-                                
-                                iterator i;
-                                iterator range_begin = _events.end();
-                                iterator range_end = _events.end();
-                                double end_value = unlocked_eval (ninfo->end_time);
-                                double start_value = unlocked_eval (ninfo->start_time - 1);
-
-                                need_adjacent_end_clamp = true;
-                                need_adjacent_start_clamp = true;
-
-                                for (i = _events.begin(); i != _events.end(); ++i) {
-
-                                        if ((*i)->when == ninfo->start_time) {
-                                                /* existing point at same time, remove it
-                                                   and the consider the next point instead.
-                                                */
-                                                i = _events.erase (i);
-
-                                                if (i == _events.end()) {
-                                                        break;
-                                                }
-
-                                                if (range_begin == _events.end()) {
-                                                        range_begin = i;
-                                                        need_adjacent_start_clamp = false;
-                                                } else {
-                                                        need_adjacent_end_clamp = false;
-                                                }
-                                                
-                                                if ((*i)->when > ninfo->end_time) {
-                                                        range_end = i;
-                                                        break;
-                                                }   
-
-                                        } else if ((*i)->when > ninfo->start_time) {
-                                                
-                                                if (range_begin == _events.end()) {
-                                                        range_begin = i;
-                                                }
-                                                
-                                                if ((*i)->when > ninfo->end_time) {
-                                                        range_end = i;
-                                                        break;
-                                                }
-                                        }
-                                }
-                                
-                                assert (range_begin != _events.end());
-                                
-                                if (range_begin != _events.begin()) {
-                                        /* clamp point before */
-                                        if (need_adjacent_start_clamp) {
-                                                _events.insert (range_begin, new ControlEvent (ninfo->start_time, start_value));
-                                        }
-                                }
-
-                                _events.insert (range_begin, nascent_events.begin(), nascent_events.end());
-
-                                if (range_end != _events.end()) {
-                                        /* clamp point after */
-                                        if (need_adjacent_end_clamp) {
-                                                _events.insert (range_begin, new ControlEvent (ninfo->end_time, end_value));
-                                        }
-                                }
-                                
-                                _events.erase (range_begin, range_end);
-                        }
-
-                        delete ninfo;
-                }
-
-                nascent.clear ();
-
-                if (writing()) {
-                        nascent.push_back (new NascentInfo (false));
-                }
-        }
-
-        maybe_signal_changed ();
+       Glib::Threads::Mutex::Lock lm (_lock);
+       /* to be used only for loading pre-sorted data from saved state */
+       _events.insert (_events.end(), new ControlEvent (when, value));
+       assert(_events.back());
+
+       mark_dirty ();
 }
 
 void
-ControlList::rt_add (double when, double value)
+ControlList::invalidate_insert_iterator ()
 {
-        // this is for automation recording 
-        
-        if (touch_enabled() && !touching()) {
-                return;
-        }
-
-       //cerr << "RT: alist " << this << " add " << value << " @ " << when << endl;
-
-        Glib::Mutex::Lock lm (_lock, Glib::TRY_LOCK);
-
-        if (lm.locked()) {
-                assert (!nascent.empty());
-                if (!nascent.back()->events.empty()) {
-                        assert (when > nascent.back()->events.back()->when);
-                }
-                nascent.back()->events.push_back (new ControlEvent (when, value));
-        }
+       Glib::Threads::Mutex::Lock lm (_lock);
+       unlocked_invalidate_insert_iterator ();
 }
 
 void
-ControlList::fast_simple_add (double when, double value)
+ControlList::unlocked_invalidate_insert_iterator ()
 {
-       /* to be used only for loading pre-sorted data from saved state */
-       _events.insert (_events.end(), new ControlEvent (when, value));
-       assert(_events.back());
+       most_recent_insert_iterator = _events.end();
+}
+
+void
+ControlList::start_write_pass (double when)
+{
+       Glib::Threads::Mutex::Lock lm (_lock);
+
+       new_write_pass = true;
+       did_write_during_pass = false;
+       insert_position = when;
+
+       /* leave the insert iterator invalid, so that we will do the lookup
+          of where it should be in a "lazy" way - deferring it until
+          we actually add the first point (which may never happen).
+       */
+
+       unlocked_invalidate_insert_iterator ();
+}
+
+void
+ControlList::write_pass_finished (double /*when*/)
+{
+       if (did_write_during_pass) {
+               thin ();
+               did_write_during_pass = false;
+       }
+       new_write_pass = true;
+       _in_write_pass = false;
+}
+
+void
+ControlList::set_in_write_pass (bool yn, bool add_point, double when)
+{
+       _in_write_pass = yn;
+
+       if (yn && add_point) {
+               add_guard_point (when);
+       }
+}
+
+void
+ControlList::add_guard_point (double when)
+{
+       ControlEvent cp (when, 0.0);
+       most_recent_insert_iterator = lower_bound (_events.begin(), _events.end(), &cp, time_comparator);
+
+       DEBUG_TRACE (DEBUG::ControlList, string_compose ("@%1 ADD GUARD POINT @ %2looked up insert iterator for new write pass\n", this, when));
+       
+       double eval_value = unlocked_eval (insert_position);
+       
+       if (most_recent_insert_iterator == _events.end()) {
+               
+               DEBUG_TRACE (DEBUG::ControlList, string_compose ("@%1 insert iterator at end, adding eval-value there %2\n", this, eval_value));
+               _events.push_back (new ControlEvent (when, eval_value));
+               /* leave insert iterator at the end */
+               
+       } else if ((*most_recent_insert_iterator)->when == when) {
+               
+               DEBUG_TRACE (DEBUG::ControlList, string_compose ("@%1 insert iterator at existing point, setting eval-value there %2\n", this, eval_value));
+               
+               /* most_recent_insert_iterator points to a control event
+                  already at the insert position, so there is
+                  nothing to do.
+                  
+                  ... except ... 
+                  
+                  advance most_recent_insert_iterator so that the "real"
+                  insert occurs in the right place, since it 
+                  points to the control event just inserted.
+               */
+               
+               ++most_recent_insert_iterator;
+       } else {
+               
+               /* insert a new control event at the right spot
+                */
+               
+               DEBUG_TRACE (DEBUG::ControlList, string_compose ("@%1 insert eval-value %2 just before iterator @ %3\n", 
+                                                                this, eval_value, (*most_recent_insert_iterator)->when));
+               
+               most_recent_insert_iterator = _events.insert (most_recent_insert_iterator, new ControlEvent (when, eval_value));
+               
+               /* advance most_recent_insert_iterator so that the "real"
+                * insert occurs in the right place, since it 
+                * points to the control event just inserted.
+                */
+               
+               ++most_recent_insert_iterator;
+       }
+       
+       /* don't do this again till the next write pass */
+       
+       new_write_pass = false;
+}
+
+bool
+ControlList::in_write_pass () const
+{
+       return _in_write_pass;
 }
 
 void
 ControlList::add (double when, double value)
 {
-        /* this is for making changes from some kind of user interface or 
-           control surface (GUI, MIDI, OSC etc) 
-        */
+       /* this is for making changes from some kind of user interface or
+          control surface (GUI, MIDI, OSC etc)
+       */
+
+       if (!clamp_value (when, value)) {
+               return;
+       }
 
+       DEBUG_TRACE (DEBUG::ControlList, string_compose ("@%1 add %2 at %3 w/erase = %4 at end ? %5\n", 
+                                                        this, value, when, _in_write_pass, (most_recent_insert_iterator == _events.end())));
        {
-               Glib::Mutex::Lock lm (_lock);
+               Glib::Threads::Mutex::Lock lm (_lock);
                ControlEvent cp (when, 0.0f);
-               bool insert = true;
                iterator insertion_point;
 
-               for (insertion_point = lower_bound (_events.begin(), _events.end(), &cp, time_comparator); insertion_point != _events.end(); ++insertion_point) {
-
-                       /* only one point allowed per time point */
+               if (_events.empty()) {
+                       
+                       /* as long as the point we're adding is not at zero,
+                        * add an "anchor" point there.
+                        */
 
-                       if ((*insertion_point)->when == when) {
-                               (*insertion_point)->value = value;
-                               insert = false;
-                               break;
+                       if (when > 1) {
+                               _events.insert (_events.end(), new ControlEvent (0, _default_value));
+                               DEBUG_TRACE (DEBUG::ControlList, string_compose ("@%1 added default value %2 at zero\n", this, _default_value));
                        }
+               }
 
-                       if ((*insertion_point)->when >= when) {
-                               break;
+               if (_in_write_pass && new_write_pass) {
+
+                       add_guard_point (insert_position);
+                       did_write_during_pass = true;
+
+               } else if (most_recent_insert_iterator == _events.end() || when > (*most_recent_insert_iterator)->when) {
+                       
+                       DEBUG_TRACE (DEBUG::ControlList, string_compose ("@%1 %2 erase from existing iterator (@end ? %3)\n", 
+                                                                        this, (_in_write_pass  ? "DO" : "DON'T"),
+                                                                        (most_recent_insert_iterator == _events.end())));
+                       
+                       if (_in_write_pass) {
+                               while (most_recent_insert_iterator != _events.end()) {
+                                       if ((*most_recent_insert_iterator)->when < when) {
+                                               if (_in_write_pass) {
+                                                       DEBUG_TRACE (DEBUG::ControlList, string_compose ("@%1 erase existing @ %2\n", this, (*most_recent_insert_iterator)));
+                                                       delete *most_recent_insert_iterator;
+                                                       most_recent_insert_iterator = _events.erase (most_recent_insert_iterator);
+                                                       continue;
+                                               }
+                                       } else if ((*most_recent_insert_iterator)->when >= when) {
+                                               break;
+                                       }
+                                       ++most_recent_insert_iterator;
+                               }
+
+                               if (most_recent_insert_iterator != _events.end()) {
+                                       if ((*most_recent_insert_iterator)->when - when > 64) {
+                                               /* next control point is some
+                                                * distance from where our new
+                                                * point is going to go - add a
+                                                * new point to avoid changing
+                                                * the shape of the line too
+                                                * much. the insert iterator needs
+                                                * to point to the new control
+                                                * point so that our insert
+                                                * will happen correctly.
+                                                */
+                                               most_recent_insert_iterator = _events.insert (most_recent_insert_iterator, 
+                                                                                             new ControlEvent (when+1, (*most_recent_insert_iterator)->value));
+                                               DEBUG_TRACE (DEBUG::ControlList, string_compose ("@%1 added post-erase guard point @ %2 = %3\n",
+                                                                                                this, when+1,
+                                                                                                (*most_recent_insert_iterator)->value));
+                                       }
+                               }        
+
+                       } else {
+                               
+                               /* not in a write pass: figure out the iterator we should insert in front of */
+
+                               DEBUG_TRACE (DEBUG::ControlList, string_compose ("compute MRI for position %1\n", when));
+                               ControlEvent cp (when, 0.0f);
+                               most_recent_insert_iterator = lower_bound (_events.begin(), _events.end(), &cp, time_comparator);
                        }
+
+               } else {
+
+                       /* not in a write pass, adding a point within existing
+                        * data: figure out the iterator we should insert in
+                        * front of 
+                        */
+                       
+                       DEBUG_TRACE (DEBUG::ControlList, string_compose ("compute(b) MRI for position %1\n", when));
+                       ControlEvent cp (when, 0.0f);
+                       most_recent_insert_iterator = lower_bound (_events.begin(), _events.end(), &cp, time_comparator);
                }
 
-               if (insert) {
+               /* OK, now we're really ready to add a new point
+                */
 
-                       _events.insert (insertion_point, new ControlEvent (when, value));
+               if (most_recent_insert_iterator == _events.end()) {
+                       DEBUG_TRACE (DEBUG::ControlList, string_compose ("@%1 appending new point at end\n", this));
+                       
+                       bool done = false;
+
+                       /* check if would just be adding to a straight line,
+                        * and don't add another point if so
+                        */
+
+                       if (!_events.empty()) { // avoid O(N) _events.size() here
+                               if (_events.back()->value == value) {
+                                       EventList::iterator b = _events.end();
+                                       --b; // final point, which we know exists
+                                       if (b != _events.begin()) { // step back again, but check first that it is legal
+                                               --b; // penultimate-point
+                                               if ((*b)->value == value) {
+                                                       /* there are at least two points with the exact same value ...
+                                                        * straight line - just move the final
+                                                        * point to the new time
+                                                        */
+                                                       _events.back()->when = when;
+                                                       done = true;
+                                                       DEBUG_TRACE (DEBUG::ControlList, string_compose ("final value of %1 moved to %2\n", value, when));
+                                               }
+                                       }
+                               }
+                       }
+
+                       if (!done) {
+                               _events.push_back (new ControlEvent (when, value));
+                               DEBUG_TRACE (DEBUG::ControlList, string_compose ("\tactually appended, size now %1\n", _events.size()));
+                       }
+
+                       if (!_in_write_pass) {
+                               most_recent_insert_iterator = _events.end();
+                               --most_recent_insert_iterator;
+                       }
+
+               } else if ((*most_recent_insert_iterator)->when == when) {
 
+                       if ((*most_recent_insert_iterator)->value != value) {
+                               DEBUG_TRACE (DEBUG::ControlList, string_compose ("@%1 reset existing point to new value %2\n", this, value));
+
+                               /* only one point allowed per time point, so just
+                                * reset the value here.
+                                */
+                               
+                               (*most_recent_insert_iterator)->value = value;
+
+                               /* if we modified the final value, then its as
+                                * if we inserted a new point as far as the
+                                * next addition, so make sure we know that.
+                                */
+
+                               if (_in_write_pass && _events.back()->when == when) {
+                                       most_recent_insert_iterator = _events.end();
+                               }
+
+                       } else {
+                               DEBUG_TRACE (DEBUG::ControlList, string_compose ("@%1 same time %2, same value value %3\n", this, when, value));
+                       }
+
+               } else {
+                       DEBUG_TRACE (DEBUG::ControlList, string_compose ("@%1 insert new point at %2 at iterator at %3\n", this, when, (*most_recent_insert_iterator)->when));
+                       
+                       bool done = false;
+                       
+                       /* check if would just be adding to a straight line,
+                        * and don't add another point if so
+                        */
+
+                       if (most_recent_insert_iterator != _events.begin()) {
+                               EventList::iterator b = most_recent_insert_iterator;
+                               --b; // prior point, which we know exists
+                               if ((*b)->value == value) { // same value as the point we plan to insert
+                                       if (b != _events.begin()) { // step back again, which may not be possible
+                                               EventList::iterator bb = b;
+                                               --bb; // next-to-prior-point
+                                               if ((*bb)->value == value) {
+                                                       /* straight line - just move the prior
+                                                        * point to the new time
+                                                        */
+                                                       (*b)->when = when;
+                                                       
+                                                       if (!_in_write_pass) {
+                                                               most_recent_insert_iterator = b;
+                                                       }
+
+                                                       DEBUG_TRACE (DEBUG::ControlList, string_compose ("final value of %1 moved to %2\n", value, when));
+                                                       done = true;
+                                               }
+                                       }
+                               }
+                       }
+
+                       if (most_recent_insert_iterator != _events.end()) {
+                               if ((*most_recent_insert_iterator)->when - when > 64) {
+                                       /* next control point is some
+                                        * distance from where our new
+                                        * point is going to go - add a
+                                        * new point to avoid changing
+                                        * the shape of the line too
+                                        * much. the insert iterator needs
+                                        * to point to the new control
+                                        * point so that our insert
+                                        * will happen correctly.
+                                        */
+                                       most_recent_insert_iterator = _events.insert (most_recent_insert_iterator, 
+                                                                                     new ControlEvent (when+1, (*most_recent_insert_iterator)->value));
+                                       DEBUG_TRACE (DEBUG::ControlList, string_compose ("@%1 added insert-post-erase guard point @ %2 = %3\n",
+                                                                                        this, when+1,
+                                                                                        (*most_recent_insert_iterator)->value));
+                               }
+                       }        
+
+                       if (!done) {
+                               EventList::iterator x = _events.insert (most_recent_insert_iterator, new ControlEvent (when, value));
+                               DEBUG_TRACE (DEBUG::ControlList, string_compose ("@%1 inserted new value before MRI, size now %2\n", this, _events.size()));
+
+                               if (!_in_write_pass) {
+                                       most_recent_insert_iterator = x;
+                               }
+                       }
                }
 
                mark_dirty ();
@@ -431,7 +671,10 @@ void
 ControlList::erase (iterator i)
 {
        {
-               Glib::Mutex::Lock lm (_lock);
+               Glib::Threads::Mutex::Lock lm (_lock);
+               if (most_recent_insert_iterator == i) {
+                       unlocked_invalidate_insert_iterator ();
+               }
                _events.erase (i);
                mark_dirty ();
        }
@@ -442,42 +685,37 @@ void
 ControlList::erase (iterator start, iterator end)
 {
        {
-               Glib::Mutex::Lock lm (_lock);
+               Glib::Threads::Mutex::Lock lm (_lock);
                _events.erase (start, end);
+               unlocked_invalidate_insert_iterator ();
                mark_dirty ();
        }
        maybe_signal_changed ();
 }
 
+/** Erase the first event which matches the given time and value */
 void
-ControlList::reset_range (double start, double endt)
+ControlList::erase (double when, double value)
 {
-       bool reset = false;
-
        {
-               Glib::Mutex::Lock lm (_lock);
-               ControlEvent cp (start, 0.0f);
-               iterator s;
-               iterator e;
+               Glib::Threads::Mutex::Lock lm (_lock);
 
-               if ((s = lower_bound (_events.begin(), _events.end(), &cp, time_comparator)) != _events.end()) {
-
-                       cp.when = endt;
-                       e = upper_bound (_events.begin(), _events.end(), &cp, time_comparator);
+               iterator i = begin ();
+               while (i != end() && ((*i)->when != when || (*i)->value != value)) {
+                       ++i;
+               }
 
-                       for (iterator i = s; i != e; ++i) {
-                               (*i)->value = _default_value;
+               if (i != end ()) {
+                       _events.erase (i);
+                       if (most_recent_insert_iterator == i) {
+                               unlocked_invalidate_insert_iterator ();
                        }
-
-                       reset = true;
-
-                       mark_dirty ();
                }
-       }
 
-       if (reset) {
-               maybe_signal_changed ();
+               mark_dirty ();
        }
+
+       maybe_signal_changed ();
 }
 
 void
@@ -486,7 +724,7 @@ ControlList::erase_range (double start, double endt)
        bool erased = false;
 
        {
-               Glib::Mutex::Lock lm (_lock);
+               Glib::Threads::Mutex::Lock lm (_lock);
                erased = erase_range_internal (start, endt, _events);
 
                if (erased) {
@@ -513,6 +751,7 @@ ControlList::erase_range_internal (double start, double endt, EventList & events
                e = upper_bound (events.begin(), events.end(), &cp, time_comparator);
                events.erase (s, e);
                if (s != e) {
+                       unlocked_invalidate_insert_iterator ();
                        erased = true;
                }
        }
@@ -524,7 +763,7 @@ void
 ControlList::slide (iterator before, double distance)
 {
        {
-               Glib::Mutex::Lock lm (_lock);
+               Glib::Threads::Mutex::Lock lm (_lock);
 
                if (before == _events.end()) {
                        return;
@@ -535,7 +774,7 @@ ControlList::slide (iterator before, double distance)
                        ++before;
                }
 
-                mark_dirty ();
+               mark_dirty ();
        }
 
        maybe_signal_changed ();
@@ -545,9 +784,9 @@ void
 ControlList::shift (double pos, double frames)
 {
        {
-               Glib::Mutex::Lock lm (_lock);
+               Glib::Threads::Mutex::Lock lm (_lock);
 
-                for (iterator i = _events.begin(); i != _events.end(); ++i) {
+               for (iterator i = _events.begin(); i != _events.end(); ++i) {
                        if ((*i)->when >= pos) {
                                (*i)->when += frames;
                        }
@@ -568,17 +807,18 @@ ControlList::modify (iterator iter, double when, double val)
        */
 
        {
-               Glib::Mutex::Lock lm (_lock);
+               Glib::Threads::Mutex::Lock lm (_lock);
 
                (*iter)->when = when;
                (*iter)->value = val;
 
-               if (isnan (val)) {
+               if (std::isnan (val)) {
                        abort ();
                }
 
                if (!_frozen) {
                        _events.sort (event_time_less_than);
+                       unlocked_invalidate_insert_iterator ();
                } else {
                        _sort_pending = true;
                }
@@ -592,7 +832,7 @@ ControlList::modify (iterator iter, double when, double val)
 std::pair<ControlList::iterator,ControlList::iterator>
 ControlList::control_points_adjacent (double xval)
 {
-       Glib::Mutex::Lock lm (_lock);
+       Glib::Threads::Mutex::Lock lm (_lock);
        iterator i;
        ControlEvent cp (xval, 0.0f);
        std::pair<iterator,iterator> ret;
@@ -622,12 +862,6 @@ ControlList::control_points_adjacent (double xval)
        return ret;
 }
 
-void
-ControlList::set_max_xval (double x)
-{
-       _max_xval = x;
-}
-
 void
 ControlList::freeze ()
 {
@@ -644,10 +878,11 @@ ControlList::thaw ()
        }
 
        {
-               Glib::Mutex::Lock lm (_lock);
+               Glib::Threads::Mutex::Lock lm (_lock);
 
                if (_sort_pending) {
                        _events.sort (event_time_less_than);
+                       unlocked_invalidate_insert_iterator ();
                        _sort_pending = false;
                }
        }
@@ -670,7 +905,7 @@ void
 ControlList::truncate_end (double last_coordinate)
 {
        {
-               Glib::Mutex::Lock lm (_lock);
+               Glib::Threads::Mutex::Lock lm (_lock);
                ControlEvent cp (last_coordinate, 0);
                ControlList::reverse_iterator i;
                double last_val;
@@ -686,7 +921,7 @@ ControlList::truncate_end (double last_coordinate)
                if (last_coordinate > _events.back()->when) {
 
                        /* extending end:
-                       */
+                        */
 
                        iterator foo = _events.begin();
                        bool lessthantwo;
@@ -761,7 +996,8 @@ ControlList::truncate_end (double last_coordinate)
                        _events.back()->when = last_coordinate;
                        _events.back()->value = last_val;
                }
-
+               
+               unlocked_invalidate_insert_iterator ();
                mark_dirty();
        }
 
@@ -772,7 +1008,7 @@ void
 ControlList::truncate_start (double overall_length)
 {
        {
-               Glib::Mutex::Lock lm (_lock);
+               Glib::Threads::Mutex::Lock lm (_lock);
                iterator i;
                double first_legal_value;
                double first_legal_coordinate;
@@ -861,6 +1097,7 @@ ControlList::truncate_start (double overall_length)
                        _events.push_front (new ControlEvent (0, first_legal_value));
                }
 
+               unlocked_invalidate_insert_iterator ();
                mark_dirty();
        }
 
@@ -1026,7 +1263,7 @@ bool
 ControlList::rt_safe_earliest_event (double start, double& x, double& y, bool inclusive) const
 {
        // FIXME: It would be nice if this was unnecessary..
-       Glib::Mutex::Lock lm(_lock, Glib::TRY_LOCK);
+       Glib::Threads::Mutex::Lock lm(_lock, Glib::Threads::TRY_LOCK);
        if (!lm.locked()) {
                return false;
        }
@@ -1088,7 +1325,7 @@ ControlList::rt_safe_earliest_event_discrete_unlocked (double start, double& x,
                        return false;
                }
 
-       /* No points in range */
+               /* No points in range */
        } else {
                return false;
        }
@@ -1109,9 +1346,9 @@ ControlList::rt_safe_earliest_event_linear_unlocked (double start, double& x, do
        const_iterator length_check_iter = _events.begin();
        if (_events.empty()) { // 0 events
                return false;
-        } else if (_events.end() == ++length_check_iter) { // 1 event
+       } else if (_events.end() == ++length_check_iter) { // 1 event
                return rt_safe_earliest_event_discrete_unlocked (start, x, y, inclusive);
-        }
+       }
 
        // Hack to avoid infinitely repeating the same event
        build_search_cache_if_necessary (start);
@@ -1130,7 +1367,7 @@ ControlList::rt_safe_earliest_event_linear_unlocked (double start, double& x, do
                        }
                        next = *_search_cache.first;
 
-               /* Step is before first */
+                       /* Step is before first */
                } else {
                        const_iterator prev = _search_cache.first;
                        --prev;
@@ -1188,11 +1425,11 @@ ControlList::rt_safe_earliest_event_linear_unlocked (double start, double& x, do
                }
 
                /*cerr << first->value << " @ " << first->when << " ... "
-                               << next->value << " @ " << next->when
-                               << " = " << y << " @ " << x << endl;*/
+                 << next->value << " @ " << next->when
+                 << " = " << y << " @ " << x << endl;*/
 
                assert(    (y >= first->value && y <= next->value)
-                               || (y <= first->value && y >= next->value) );
+                          || (y <= first->value && y >= next->value) );
 
 
                const bool past_start = (inclusive ? x >= start : x > start);
@@ -1206,7 +1443,7 @@ ControlList::rt_safe_earliest_event_linear_unlocked (double start, double& x, do
                        return false;
                }
 
-       /* No points in the future, so no steps (towards them) in the future */
+               /* No points in the future, so no steps (towards them) in the future */
        } else {
                return false;
        }
@@ -1222,14 +1459,14 @@ ControlList::cut_copy_clear (double start, double end, int op)
 {
        boost::shared_ptr<ControlList> nal = create (_parameter);
        iterator s, e;
-        ControlEvent cp (start, 0.0);
+       ControlEvent cp (start, 0.0);
 
        {
-               Glib::Mutex::Lock lm (_lock);
+               Glib::Threads::Mutex::Lock lm (_lock);
 
-                /* first, determine s & e, two iterators that define the range of points
-                   affected by this operation
-                */
+               /* first, determine s & e, two iterators that define the range of points
+                  affected by this operation
+               */
 
                if ((s = lower_bound (_events.begin(), _events.end(), &cp, time_comparator)) == _events.end()) {
                        return nal;
@@ -1240,43 +1477,43 @@ ControlList::cut_copy_clear (double start, double end, int op)
                e = upper_bound (_events.begin(), _events.end(), &cp, time_comparator);
 
 
-                /* if "start" isn't the location of an existing point,
-                   evaluate the curve to get a value for the start. Add a point to
-                   both the existing event list, and if its not a "clear" operation,
-                   to the copy ("nal") as well. 
+               /* if "start" isn't the location of an existing point,
+                  evaluate the curve to get a value for the start. Add a point to
+                  both the existing event list, and if its not a "clear" operation,
+                  to the copy ("nal") as well.
+
+                  Note that the time positions of the points in each list are different
+                  because we want the copy ("nal") to have a zero time reference.
+               */
+
 
-                   Note that the time positions of the points in each list are different 
-                   because we want the copy ("nal") to have a zero time reference.
-                */
+               /* before we begin any cut/clear operations, get the value of the curve
+                  at "end".
+               */
 
-                        
-                /* before we begin any cut/clear operations, get the value of the curve
-                   at "end".
-                */
+               double end_value = unlocked_eval (end);
 
-                double end_value = unlocked_eval (end);
+               if ((*s)->when != start) {
 
-                if ((*s)->when != start) {
-                        
-                        double val = unlocked_eval (start);
+                       double val = unlocked_eval (start);
 
                        if (op == 0) { // cut
                                if (start > _events.front()->when) {
                                        _events.insert (s, (new ControlEvent (start, val)));
                                }
                        }
-                        
-                        if (op != 2) { // ! clear
-                                nal->_events.push_back (new ControlEvent (0, val));
-                        }
-                }
+
+                       if (op != 2) { // ! clear
+                               nal->_events.push_back (new ControlEvent (0, val));
+                       }
+               }
 
                for (iterator x = s; x != e; ) {
 
                        /* adjust new points to be relative to start, which
                           has been set to zero.
                        */
-                       
+
                        if (op != 2) {
                                nal->_events.push_back (new ControlEvent ((*x)->when - start, (*x)->value));
                        }
@@ -1284,30 +1521,31 @@ ControlList::cut_copy_clear (double start, double end, int op)
                        if (op != 1) {
                                x = _events.erase (x);
                        } else {
-                                ++x;
-                        }
+                               ++x;
+                       }
                }
-                
-                if (e == _events.end() || (*e)->when != end) {
 
-                        /* only add a boundary point if there is a point after "end"
-                         */
+               if (e == _events.end() || (*e)->when != end) {
 
-                        if (op == 0 && (e != _events.end() && end < (*e)->when)) { // cut
-                                _events.insert (e, new ControlEvent (end, end_value));
-                        }
+                       /* only add a boundary point if there is a point after "end"
+                        */
 
-                        if (op != 2 && (e != _events.end() && end < (*e)->when)) { // cut/copy
-                                nal->_events.push_back (new ControlEvent (end - start, end_value));
-                        }
+                       if (op == 0 && (e != _events.end() && end < (*e)->when)) { // cut
+                               _events.insert (e, new ControlEvent (end, end_value));
+                       }
+
+                       if (op != 2 && (e != _events.end() && end < (*e)->when)) { // cut/copy
+                               nal->_events.push_back (new ControlEvent (end - start, end_value));
+                       }
                }
 
-                mark_dirty ();
+               unlocked_invalidate_insert_iterator ();
+               mark_dirty ();
        }
 
-        if (op != 1) {
-                maybe_signal_changed ();
-        }
+       if (op != 1) {
+               maybe_signal_changed ();
+       }
 
        return nal;
 }
@@ -1340,7 +1578,7 @@ ControlList::paste (ControlList& alist, double pos, float /*times*/)
        }
 
        {
-               Glib::Mutex::Lock lm (_lock);
+               Glib::Threads::Mutex::Lock lm (_lock);
                iterator where;
                iterator prev;
                double end = 0;
@@ -1371,6 +1609,7 @@ ControlList::paste (ControlList& alist, double pos, float /*times*/)
                        }
                }
 
+               unlocked_invalidate_insert_iterator ();
                mark_dirty ();
        }
 
@@ -1387,7 +1626,7 @@ ControlList::move_ranges (const list< RangeMove<double> >& movements)
        typedef list< RangeMove<double> > RangeMoveList;
 
        {
-               Glib::Mutex::Lock lm (_lock);
+               Glib::Threads::Mutex::Lock lm (_lock);
 
                /* a copy of the events list before we started moving stuff around */
                EventList old_events = _events;
@@ -1427,6 +1666,7 @@ ControlList::move_ranges (const list< RangeMove<double> >& movements)
 
                if (!_frozen) {
                        _events.sort (event_time_less_than);
+                       unlocked_invalidate_insert_iterator ();
                } else {
                        _sort_pending = true;
                }
@@ -1449,5 +1689,49 @@ ControlList::set_interpolation (InterpolationStyle s)
        InterpolationChanged (s); /* EMIT SIGNAL */
 }
 
+void
+ControlList::set_thinning_factor (double v)
+{
+       _thinning_factor = v;
+}
+
+bool
+ControlList::operator!= (ControlList const & other) const
+{
+       if (_events.size() != other._events.size()) {
+               return true;
+       }
+
+       EventList::const_iterator i = _events.begin ();
+       EventList::const_iterator j = other._events.begin ();
+
+       while (i != _events.end() && (*i)->when == (*j)->when && (*i)->value == (*j)->value) {
+               ++i;
+               ++j;
+       }
+
+       if (i != _events.end ()) {
+               return true;
+       }
+       
+       return (
+               _parameter != other._parameter ||
+               _interpolation != other._interpolation ||
+               _min_yval != other._min_yval ||
+               _max_yval != other._max_yval ||
+               _default_value != other._default_value
+               );
+}
+
+void
+ControlList::dump (ostream& o)
+{
+       /* NOT LOCKED ... for debugging only */
+
+       for (EventList::iterator x = _events.begin(); x != _events.end(); ++x) {
+               o << (*x)->value << " @ " << (*x)->when << endl;
+       }
+}
+
 } // namespace Evoral