automation_line.cc

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/*
    Copyright (C) 2002-2003 Paul Davis

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.

*/

#include <cmath>

#ifdef COMPILER_MSVC
#include <float.h>

// 'std::isnan()' is not available in MSVC.
#define isnan_local(val) (bool)_isnan((double)val)
#else
#define isnan_local std::isnan
#endif

#include <climits>
#include <vector>
#include <fstream>

#include "boost/shared_ptr.hpp"

#include "pbd/floating.h"
#include "pbd/memento_command.h"
#include "pbd/stl_delete.h"
#include "pbd/stacktrace.h"

#include "ardour/automation_list.h"
#include "ardour/dB.h"
#include "ardour/debug.h"
#include "ardour/parameter_types.h"
#include "ardour/tempo.h"

#include "evoral/Curve.hpp"

#include "canvas/debug.h"

#include "automation_line.h"
#include "control_point.h"
#include "gui_thread.h"
#include "rgb_macros.h"
#include "ardour_ui.h"
#include "public_editor.h"
#include "selection.h"
#include "time_axis_view.h"
#include "point_selection.h"
#include "automation_time_axis.h"

#include "ardour/event_type_map.h"
#include "ardour/session.h"
#include "ardour/value_as_string.h"

#include "i18n.h"

using namespace std;
using namespace ARDOUR;
using namespace PBD;
using namespace Editing;

AutomationLine::AutomationLine (const string&                              name,
                                TimeAxisView&                              tv,
                                ArdourCanvas::Item&                        parent,
                                boost::shared_ptr<AutomationList>          al,
                                const ParameterDescriptor&                 desc,
                                Evoral::TimeConverter<double, framepos_t>* converter)
        : trackview (tv)
        , _name (name)
        , alist (al)
        , _time_converter (converter ? converter : new Evoral::IdentityConverter<double, framepos_t>)
        , _parent_group (parent)
        , _offset (0)
        , _maximum_time (max_framepos)
        , _desc (desc)
{
        if (converter) {
                _our_time_converter = false;
        } else {
                _our_time_converter = true;
        }
        
        _visible = Line;

        update_pending = false;
        have_timeout = false;
        _uses_gain_mapping = false;
        no_draw = false;
        _is_boolean = false;
        terminal_points_can_slide = true;
        _height = 0;

        group = new ArdourCanvas::Container (&parent, ArdourCanvas::Duple(0, 1.5));
        CANVAS_DEBUG_NAME (group, "region gain envelope group");

        line = new ArdourCanvas::PolyLine (group);
        CANVAS_DEBUG_NAME (line, "region gain envelope line");
        line->set_data ("line", this);
        line->set_outline_width (2.0);
        line->set_covers_threshold (4.0);

        line->Event.connect (sigc::mem_fun (*this, &AutomationLine::event_handler));

        trackview.session()->register_with_memento_command_factory(alist->id(), this);

        if (alist->parameter().type() == GainAutomation ||
            alist->parameter().type() == TrimAutomation ||
            alist->parameter().type() == EnvelopeAutomation ||
            desc.unit == ParameterDescriptor::DB) {
                set_uses_gain_mapping (true);
        }

        interpolation_changed (alist->interpolation ());

        connect_to_list ();
}

AutomationLine::~AutomationLine ()
{
        vector_delete (&control_points);
        delete group;

        if (_our_time_converter) {
                delete _time_converter;
        }
}

bool
AutomationLine::event_handler (GdkEvent* event)
{
        return PublicEditor::instance().canvas_line_event (event, line, this);
}

bool
AutomationLine::is_stepped() const
{
        return (_desc.toggled ||
                (alist && alist->interpolation() == AutomationList::Discrete));
}

void
AutomationLine::update_visibility ()
{
        if (_visible & Line) {
                /* Only show the line when there are some points, otherwise we may show an out-of-date line
                   when automation points have been removed (the line will still follow the shape of the
                   old points).
                */
                if (control_points.size() >= 2) {
                        line->show();
                } else {
                        line->hide ();
                }

                if (_visible & ControlPoints) {
                        for (vector<ControlPoint*>::iterator i = control_points.begin(); i != control_points.end(); ++i) {
                                (*i)->show ();
                        }
                } else if (_visible & SelectedControlPoints) {
                        for (vector<ControlPoint*>::iterator i = control_points.begin(); i != control_points.end(); ++i) {
                                if ((*i)->get_selected()) {
                                        (*i)->show ();
                                } else {
                                        (*i)->hide ();
                                }
                        }
                } else {
                        for (vector<ControlPoint*>::iterator i = control_points.begin(); i != control_points.end(); ++i) {
                                (*i)->hide ();
                        }
                }

        } else {
                line->hide ();
                for (vector<ControlPoint*>::iterator i = control_points.begin(); i != control_points.end(); ++i) {
                        if (_visible & ControlPoints) {
                                (*i)->show ();
                        } else {
                                (*i)->hide ();
                        }
                }
        }

}

void
AutomationLine::hide ()
{
        /* leave control points setting unchanged, we are just hiding the
           overall line 
        */
        
        set_visibility (AutomationLine::VisibleAspects (_visible & ~Line));
}

double
AutomationLine::control_point_box_size ()
{
        if (_height > TimeAxisView::preset_height (HeightLarger)) {
                return 8.0;
        } else if (_height > (guint32) TimeAxisView::preset_height (HeightNormal)) {
                return 6.0;
        }
        return 4.0;
}

void
AutomationLine::set_height (guint32 h)
{
        if (h != _height) {
                _height = h;

                double bsz = control_point_box_size();

                for (vector<ControlPoint*>::iterator i = control_points.begin(); i != control_points.end(); ++i) {
                        (*i)->set_size (bsz);
                }

                reset ();
        }
}

void
AutomationLine::set_line_color (uint32_t color)
{
        _line_color = color;
        line->set_outline_color (color);
}

void
AutomationLine::set_uses_gain_mapping (bool yn)
{
        if (yn != _uses_gain_mapping) {
                _uses_gain_mapping = yn;
                reset ();
        }
}

ControlPoint*
AutomationLine::nth (uint32_t n)
{
        if (n < control_points.size()) {
                return control_points[n];
        } else {
                return 0;
        }
}

ControlPoint const *
AutomationLine::nth (uint32_t n) const
{
        if (n < control_points.size()) {
                return control_points[n];
        } else {
                return 0;
        }
}

void
AutomationLine::modify_point_y (ControlPoint& cp, double y)
{
        /* clamp y-coord appropriately. y is supposed to be a normalized fraction (0.0-1.0),
           and needs to be converted to a canvas unit distance.
        */

        y = max (0.0, y);
        y = min (1.0, y);
        y = _height - (y * _height);

        double const x = trackview.editor().sample_to_pixel_unrounded (_time_converter->to((*cp.model())->when) - _offset);

        trackview.editor().begin_reversible_command (_("automation event move"));
        trackview.editor().session()->add_command (
                new MementoCommand<AutomationList> (memento_command_binder(), &get_state(), 0));

        cp.move_to (x, y, ControlPoint::Full);

        alist->freeze ();
        sync_model_with_view_point (cp);
        alist->thaw ();

        reset_line_coords (cp);

        if (line_points.size() > 1) {
                line->set_steps (line_points, is_stepped());
        }

        update_pending = false;

        trackview.editor().session()->add_command (
                new MementoCommand<AutomationList> (memento_command_binder(), 0, &alist->get_state()));

        trackview.editor().commit_reversible_command ();
        trackview.editor().session()->set_dirty ();
}

void
AutomationLine::reset_line_coords (ControlPoint& cp)
{
        if (cp.view_index() < line_points.size()) {
                line_points[cp.view_index()].x = cp.get_x ();
                line_points[cp.view_index()].y = cp.get_y ();
        }
}

bool
AutomationLine::sync_model_with_view_points (list<ControlPoint*> cp)
{
        update_pending = true;

        bool moved = false;
        for (list<ControlPoint*>::iterator i = cp.begin(); i != cp.end(); ++i) {
                moved = sync_model_with_view_point (**i) || moved;
        }

        return moved;
}

string
AutomationLine::get_verbose_cursor_string (double fraction) const
{
        std::string s = fraction_to_string (fraction);
        if (_uses_gain_mapping) {
                s += " dB";
        }

        return s;
}

string
AutomationLine::get_verbose_cursor_relative_string (double original, double fraction) const
{
        std::string s = fraction_to_string (fraction);
        if (_uses_gain_mapping) {
                s += " dB";
        }

        std::string d = fraction_to_relative_string (original, fraction);

        if (!d.empty()) {

                s += " (\u0394";
                s += d;

                if (_uses_gain_mapping) {
                        s += " dB";
                }

                s += ')';
        }

        return s;
}

string
AutomationLine::fraction_to_string (double fraction) const
{
        if (_uses_gain_mapping) {
                char buf[32];
                if (_desc.type == GainAutomation || _desc.type == EnvelopeAutomation || _desc.lower == 0) {
                        if (fraction == 0.0) {
                                snprintf (buf, sizeof (buf), "-inf");
                        } else {
                                snprintf (buf, sizeof (buf), "%.1f", accurate_coefficient_to_dB (slider_position_to_gain_with_max (fraction, _desc.upper)));
                        }
                } else {
                        const double lower_db = accurate_coefficient_to_dB (_desc.lower);
                        const double range_db = accurate_coefficient_to_dB (_desc.upper) - lower_db;
                        snprintf (buf, sizeof (buf), "%.1f", lower_db + fraction * range_db);
                }
                return buf;
        } else {
                view_to_model_coord_y (fraction);
                return ARDOUR::value_as_string (_desc, fraction);
        }

        return ""; /*NOTREACHED*/
}

string
AutomationLine::fraction_to_relative_string (double original, double fraction) const
{
        char buf[32];

        if (original == fraction) {
                return "0";
        }

        if (_uses_gain_mapping) {
                if (original == 0.0) {
                        /* there is no sensible representation of a relative
                           change from -inf dB, so return an empty string.
                        */
                        return "";
                } else if (fraction == 0.0) {
                        snprintf (buf, sizeof (buf), "-inf");
                } else {
                        double old_db = accurate_coefficient_to_dB (slider_position_to_gain_with_max (original, Config->get_max_gain()));
                        double new_db = accurate_coefficient_to_dB (slider_position_to_gain_with_max (fraction, Config->get_max_gain()));
                        snprintf (buf, sizeof (buf), "%.1f", new_db - old_db);
                }
        } else {
                view_to_model_coord_y (original);
                view_to_model_coord_y (fraction);
                return ARDOUR::value_as_string (_desc, fraction - original);
        }

        return buf;
}

double
AutomationLine::string_to_fraction (string const & s) const
{
        if (s == "-inf") {
                return 0;
        }

        double v;
        sscanf (s.c_str(), "%lf", &v);

        if (_uses_gain_mapping) {
                v = gain_to_slider_position_with_max (dB_to_coefficient (v), Config->get_max_gain());
        } else {
                double dummy = 0.0;
                model_to_view_coord (dummy, v);
        }

        return v;
}

void
AutomationLine::start_drag_single (ControlPoint* cp, double x, float fraction)
{
        trackview.editor().begin_reversible_command (_("automation event move"));
        trackview.editor().session()->add_command (
                new MementoCommand<AutomationList> (memento_command_binder(), &get_state(), 0));

        _drag_points.clear ();
        _drag_points.push_back (cp);

        if (cp->get_selected ()) {
                for (vector<ControlPoint*>::iterator i = control_points.begin(); i != control_points.end(); ++i) {
                        if (*i != cp && (*i)->get_selected()) {
                                _drag_points.push_back (*i);
                        }
                }
        }

        start_drag_common (x, fraction);
}

void
AutomationLine::start_drag_line (uint32_t i1, uint32_t i2, float fraction)
{
        trackview.editor().begin_reversible_command (_("automation range move"));
        trackview.editor().session()->add_command (
                new MementoCommand<AutomationList> (memento_command_binder (), &get_state(), 0));

        _drag_points.clear ();

        for (uint32_t i = i1; i <= i2; i++) {
                _drag_points.push_back (nth (i));
        }

        start_drag_common (0, fraction);
}

void
AutomationLine::start_drag_multiple (list<ControlPoint*> cp, float fraction, XMLNode* state)
{
        trackview.editor().begin_reversible_command (_("automation range move"));
        trackview.editor().session()->add_command (
                new MementoCommand<AutomationList> (memento_command_binder(), state, 0));

        _drag_points = cp;
        start_drag_common (0, fraction);
}

struct ControlPointSorter
{
        bool operator() (ControlPoint const * a, ControlPoint const * b) const {
                if (floateq (a->get_x(), b->get_x(), 1)) {
                        return a->view_index() < b->view_index();
                } 
                return a->get_x() < b->get_x();
        }
};

AutomationLine::ContiguousControlPoints::ContiguousControlPoints (AutomationLine& al)
        : line (al), before_x (0), after_x (DBL_MAX) 
{
}

void
AutomationLine::ContiguousControlPoints::compute_x_bounds (PublicEditor& e)
{
        uint32_t sz = size();

        if (sz > 0 && sz < line.npoints()) {
                const TempoMap& map (e.session()->tempo_map());

                /* determine the limits on x-axis motion for this 
                   contiguous range of control points
                */

                if (front()->view_index() > 0) {
                        before_x = line.nth (front()->view_index() - 1)->get_x();

                        const framepos_t pos = e.pixel_to_sample(before_x);
                        const Meter& meter = map.meter_at (pos);
                        const framecnt_t len = ceil (meter.frames_per_bar (map.tempo_at (pos), e.session()->frame_rate())
                                        / (Timecode::BBT_Time::ticks_per_beat * meter.divisions_per_bar()) );
                        const double one_tick_in_pixels = e.sample_to_pixel_unrounded (len);

                        before_x += one_tick_in_pixels;
                }

                /* if our last point has a point after it in the line,
                   we have an "after" bound
                */

                if (back()->view_index() < (line.npoints() - 1)) {
                        after_x = line.nth (back()->view_index() + 1)->get_x();

                        const framepos_t pos = e.pixel_to_sample(after_x);
                        const Meter& meter = map.meter_at (pos);
                        const framecnt_t len = ceil (meter.frames_per_bar (map.tempo_at (pos), e.session()->frame_rate())
                                        / (Timecode::BBT_Time::ticks_per_beat * meter.divisions_per_bar()));
                        const double one_tick_in_pixels = e.sample_to_pixel_unrounded (len);

                        after_x -= one_tick_in_pixels;
                }
        }
}

double 
AutomationLine::ContiguousControlPoints::clamp_dx (double dx) 
{
        if (empty()) {
                return dx;
        }

        /* get the maximum distance we can move any of these points along the x-axis
         */
        
        double tx; /* possible position a point would move to, given dx */
        ControlPoint* cp;
        
        if (dx > 0) {
                /* check the last point, since we're moving later in time */
                cp = back();
        } else {
                /* check the first point, since we're moving earlier in time */
                cp = front();
        }

        tx = cp->get_x() + dx; // new possible position if we just add the motion 
        tx = max (tx, before_x); // can't move later than following point
        tx = min (tx, after_x);  // can't move earlier than preceeding point
        return  tx - cp->get_x (); 
}

void 
AutomationLine::ContiguousControlPoints::move (double dx, double dy) 
{
        for (std::list<ControlPoint*>::iterator i = begin(); i != end(); ++i) {
                (*i)->move_to ((*i)->get_x() + dx, (*i)->get_y() - line.height() * dy, ControlPoint::Full);
                line.reset_line_coords (**i);
        }
}

void
AutomationLine::start_drag_common (double x, float fraction)
{
        _drag_x = x;
        _drag_distance = 0;
        _last_drag_fraction = fraction;
        _drag_had_movement = false;
        did_push = false;

        /* they are probably ordered already, but we have to make sure */

        _drag_points.sort (ControlPointSorter());
}


pair<double, float>
AutomationLine::drag_motion (double const x, float fraction, bool ignore_x, bool with_push, uint32_t& final_index)
{
        if (_drag_points.empty()) {
                return pair<double,float> (x,fraction);
        }

        double dx = ignore_x ? 0 : (x - _drag_x);
        double dy = fraction - _last_drag_fraction;

        if (!_drag_had_movement) {

                /* "first move" ... do some stuff that we don't want to do if 
                   no motion ever took place, but need to do before we handle
                   motion.
                */
        
                /* partition the points we are dragging into (potentially several)
                 * set(s) of contiguous points. this will not happen with a normal
                 * drag, but if the user does a discontiguous selection, it can.
                 */
                
                uint32_t expected_view_index = 0;
                CCP contig;
                
                for (list<ControlPoint*>::iterator i = _drag_points.begin(); i != _drag_points.end(); ++i) {
                        if (i == _drag_points.begin() || (*i)->view_index() != expected_view_index) {
                                contig.reset (new ContiguousControlPoints (*this));
                                contiguous_points.push_back (contig);
                        }
                        contig->push_back (*i);
                        expected_view_index = (*i)->view_index() + 1;
                }

                if (contiguous_points.back()->empty()) {
                        contiguous_points.pop_back ();
                }

                for (vector<CCP>::iterator ccp = contiguous_points.begin(); ccp != contiguous_points.end(); ++ccp) {
                        (*ccp)->compute_x_bounds (trackview.editor());
                }
        }       

        /* OK, now on to the stuff related to *this* motion event. First, for
         * each contiguous range, figure out the maximum x-axis motion we are
         * allowed (because of neighbouring points that are not moving.
         * 
         * if we are moving forwards with push, we don't need to do this, 
         * since all later points will move too.
         */

        if (dx < 0 || ((dx > 0) && !with_push)) {
                for (vector<CCP>::iterator ccp = contiguous_points.begin(); ccp != contiguous_points.end(); ++ccp) {
                        double dxt = (*ccp)->clamp_dx (dx);
                        if (fabs (dxt) < fabs (dx)) {
                                dx = dxt;
                        }
                }
        }

        /* clamp y */
        
        for (list<ControlPoint*>::iterator i = _drag_points.begin(); i != _drag_points.end(); ++i) {
                double const y = ((_height - (*i)->get_y()) / _height) + dy;
                if (y < 0) {
                        dy -= y;
                }
                if (y > 1) {
                        dy -= (y - 1);
                }
        }

        if (dx || dy) {

                /* and now move each section */
                
                for (vector<CCP>::iterator ccp = contiguous_points.begin(); ccp != contiguous_points.end(); ++ccp) {
                        (*ccp)->move (dx, dy);
                }
                if (with_push) {
                        final_index = contiguous_points.back()->back()->view_index () + 1;
                        ControlPoint* p;
                        uint32_t i = final_index;
                        while ((p = nth (i)) != 0 && p->can_slide()) {
                                p->move_to (p->get_x() + dx, p->get_y(), ControlPoint::Full);
                                reset_line_coords (*p);
                                ++i;
                        }
                }

                /* update actual line coordinates (will queue a redraw)
                 */

                if (line_points.size() > 1) {
                        line->set_steps (line_points, is_stepped());
                }
        }
        
        _drag_distance += dx;
        _drag_x += dx;
        _last_drag_fraction = fraction;
        _drag_had_movement = true;
        did_push = with_push;

        return pair<double, float> (_drag_x + dx, _last_drag_fraction + dy);
}

void
AutomationLine::end_drag (bool with_push, uint32_t final_index)
{
        if (!_drag_had_movement) {
                return;
        }

        alist->freeze ();
        bool moved = sync_model_with_view_points (_drag_points);

        if (with_push) {
                ControlPoint* p;
                uint32_t i = final_index;
                while ((p = nth (i)) != 0 && p->can_slide()) {
                        moved = sync_model_with_view_point (*p) || moved;
                        ++i;
                }
        }

        alist->thaw ();

        update_pending = false;

        if (moved) {
                /* A point has moved as a result of sync (clamped to integer or boolean
                   value), update line accordingly. */
                line->set_steps (line_points, is_stepped());
        }

        trackview.editor().session()->add_command (
                new MementoCommand<AutomationList>(memento_command_binder (), 0, &alist->get_state()));

        trackview.editor().session()->set_dirty ();
        did_push = false;

        contiguous_points.clear ();
}

bool
AutomationLine::sync_model_with_view_point (ControlPoint& cp)
{
        /* find out where the visual control point is.
           initial results are in canvas units. ask the
           line to convert them to something relevant.
        */

        double view_x = cp.get_x();
        double view_y = 1.0 - (cp.get_y() / _height);

        /* if xval has not changed, set it directly from the model to avoid rounding errors */

        if (view_x == trackview.editor().sample_to_pixel_unrounded (_time_converter->to ((*cp.model())->when)) - _offset) {
                view_x = (*cp.model())->when - _offset;
        } else {
                view_x = trackview.editor().pixel_to_sample (view_x);
                view_x = _time_converter->from (view_x + _offset);
        }

        update_pending = true;

        view_to_model_coord_y (view_y);

        alist->modify (cp.model(), view_x, view_y);

        /* convert back from model to view y for clamping position (for integer/boolean/etc) */
        model_to_view_coord_y (view_y);
        const double point_y = _height - (view_y * _height);
        if (point_y != cp.get_y()) {
                cp.move_to (cp.get_x(), point_y, ControlPoint::Full);
                reset_line_coords (cp);
                return true;
        }

        return false;
}

bool
AutomationLine::control_points_adjacent (double xval, uint32_t & before, uint32_t& after)
{
        ControlPoint *bcp = 0;
        ControlPoint *acp = 0;
        double unit_xval;

        unit_xval = trackview.editor().sample_to_pixel_unrounded (xval);

        for (vector<ControlPoint*>::iterator i = control_points.begin(); i != control_points.end(); ++i) {

                if ((*i)->get_x() <= unit_xval) {

                        if (!bcp || (*i)->get_x() > bcp->get_x()) {
                                bcp = *i;
                                before = bcp->view_index();
                        }

                } else if ((*i)->get_x() > unit_xval) {
                        acp = *i;
                        after = acp->view_index();
                        break;
                }
        }

        return bcp && acp;
}

bool
AutomationLine::is_last_point (ControlPoint& cp)
{
        // If the list is not empty, and the point is the last point in the list

        if (alist->empty()) {
                return false;
        }

        AutomationList::const_iterator i = alist->end();
        --i;

        if (cp.model() == i) {
                return true;
        }

        return false;
}

bool
AutomationLine::is_first_point (ControlPoint& cp)
{
        // If the list is not empty, and the point is the first point in the list

        if (!alist->empty() && cp.model() == alist->begin()) {
                return true;
        }

        return false;
}

// This is copied into AudioRegionGainLine
void
AutomationLine::remove_point (ControlPoint& cp)
{
        trackview.editor().begin_reversible_command (_("remove control point"));
        XMLNode &before = alist->get_state();

        alist->erase (cp.model());
        
        trackview.editor().session()->add_command(
                new MementoCommand<AutomationList> (memento_command_binder (), &before, &alist->get_state()));

        trackview.editor().commit_reversible_command ();
        trackview.editor().session()->set_dirty ();
}

void
AutomationLine::get_selectables (framepos_t start, framepos_t end, double botfrac, double topfrac, list<Selectable*>& results)
{
        /* convert fractions to display coordinates with 0 at the top of the track */
        double const bot_track = (1 - topfrac) * trackview.current_height ();
        double const top_track = (1 - botfrac) * trackview.current_height ();

        for (vector<ControlPoint*>::iterator i = control_points.begin(); i != control_points.end(); ++i) {
                double const model_when = (*(*i)->model())->when;

                /* model_when is relative to the start of the source, so we just need to add on the origin_b here
                   (as it is the session frame position of the start of the source)
                */
                
                framepos_t const session_frames_when = _time_converter->to (model_when) + _time_converter->origin_b ();

                if (session_frames_when >= start && session_frames_when <= end && (*i)->get_y() >= bot_track && (*i)->get_y() <= top_track) {
                        results.push_back (*i);
                }
        }
}

void
AutomationLine::get_inverted_selectables (Selection&, list<Selectable*>& /*results*/)
{
        // hmmm ....
}

void
AutomationLine::set_selected_points (PointSelection const & points)
{
        for (vector<ControlPoint*>::iterator i = control_points.begin(); i != control_points.end(); ++i) {
                (*i)->set_selected (false);
        }

        for (PointSelection::const_iterator i = points.begin(); i != points.end(); ++i) {
                (*i)->set_selected (true);
        }

        if (points.empty()) {
                remove_visibility (SelectedControlPoints);
        } else {
                add_visibility (SelectedControlPoints);
        }

        set_colors ();
}

void AutomationLine::set_colors ()
{
        set_line_color (ARDOUR_UI::config()->color ("automation line"));
        for (vector<ControlPoint*>::iterator i = control_points.begin(); i != control_points.end(); ++i) {
                (*i)->set_color ();
        }
}

void
AutomationLine::list_changed ()
{
        DEBUG_TRACE (DEBUG::Automation, string_compose ("\tline changed, existing update pending? %1\n", update_pending));

        if (!update_pending) {
                update_pending = true;
                Gtkmm2ext::UI::instance()->call_slot (invalidator (*this), boost::bind (&AutomationLine::queue_reset, this));
        }
}

void
AutomationLine::reset_callback (const Evoral::ControlList& events)
{
        uint32_t vp = 0;
        uint32_t pi = 0;
        uint32_t np;

        if (events.empty()) {
                for (vector<ControlPoint*>::iterator i = control_points.begin(); i != control_points.end(); ++i) {
                        delete *i;
                }
                control_points.clear ();
                line->hide();
                return;
        }

        /* hide all existing points, and the line */

        for (vector<ControlPoint*>::iterator i = control_points.begin(); i != control_points.end(); ++i) {
                (*i)->hide();
        }

        line->hide ();
        np = events.size();

        Evoral::ControlList& e = const_cast<Evoral::ControlList&> (events);
        
        for (AutomationList::iterator ai = e.begin(); ai != e.end(); ++ai, ++pi) {

                double tx = (*ai)->when;
                double ty = (*ai)->value;

                /* convert from model coordinates to canonical view coordinates */

                model_to_view_coord (tx, ty);

                if (isnan_local (tx) || isnan_local (ty)) {
                        warning << string_compose (_("Ignoring illegal points on AutomationLine \"%1\""),
                                                   _name) << endmsg;
                        continue;
                }
                
                if (tx >= max_framepos || tx < 0 || tx >= _maximum_time) {
                        continue;
                }
                
                /* convert x-coordinate to a canvas unit coordinate (this takes
                 * zoom and scroll into account).
                 */
                        
                tx = trackview.editor().sample_to_pixel_unrounded (tx);
                
                /* convert from canonical view height (0..1.0) to actual
                 * height coordinates (using X11's top-left rooted system)
                 */

                ty = _height - (ty * _height);

                add_visible_control_point (vp, pi, tx, ty, ai, np);
                vp++;
        }

        /* discard extra CP's to avoid confusing ourselves */

        while (control_points.size() > vp) {
                ControlPoint* cp = control_points.back();
                control_points.pop_back ();
                delete cp;
        }

        if (!terminal_points_can_slide) {
                control_points.back()->set_can_slide(false);
        }

        if (vp > 1) {

                /* reset the line coordinates given to the CanvasLine */

                while (line_points.size() < vp) {
                        line_points.push_back (ArdourCanvas::Duple (0,0));
                }

                while (line_points.size() > vp) {
                        line_points.pop_back ();
                }

                for (uint32_t n = 0; n < vp; ++n) {
                        line_points[n].x = control_points[n]->get_x();
                        line_points[n].y = control_points[n]->get_y();
                }

                line->set_steps (line_points, is_stepped());

                update_visibility ();
        }

        set_selected_points (trackview.editor().get_selection().points);
}

void
AutomationLine::reset ()
{
        DEBUG_TRACE (DEBUG::Automation, "\t\tLINE RESET\n");
        update_pending = false;
        have_timeout = false;

        if (no_draw) {
                return;
        }

        alist->apply_to_points (*this, &AutomationLine::reset_callback);
}

void
AutomationLine::queue_reset ()
{
        /* this must be called from the GUI thread
         */

        if (trackview.editor().session()->transport_rolling() && alist->automation_write()) {
                /* automation write pass ... defer to a timeout */
                /* redraw in 1/4 second */
                if (!have_timeout) {
                        DEBUG_TRACE (DEBUG::Automation, "\tqueue timeout\n");
                        Glib::signal_timeout().connect (sigc::bind_return (sigc::mem_fun (*this, &AutomationLine::reset), false), 250);
                        have_timeout = true;
                } else {
                        DEBUG_TRACE (DEBUG::Automation, "\ttimeout already queued, change ignored\n");
                }
        } else {
                reset ();
        }
}

void
AutomationLine::clear ()
{
        /* parent must create and commit command */
        XMLNode &before = alist->get_state();
        alist->clear();

        trackview.editor().session()->add_command (
                new MementoCommand<AutomationList> (memento_command_binder (), &before, &alist->get_state()));
}

void
AutomationLine::set_list (boost::shared_ptr<ARDOUR::AutomationList> list)
{
        alist = list;
        queue_reset ();
        connect_to_list ();
}

void
AutomationLine::add_visibility (VisibleAspects va)
{
        VisibleAspects old = _visible;

        _visible = VisibleAspects (_visible | va);

        if (old != _visible) {
                update_visibility ();
        }
}

void
AutomationLine::set_visibility (VisibleAspects va)
{
        if (_visible != va) {
                _visible = va;
                update_visibility ();
        }
}

void
AutomationLine::remove_visibility (VisibleAspects va)
{
        VisibleAspects old = _visible;

        _visible = VisibleAspects (_visible & ~va);

        if (old != _visible) {
                update_visibility ();
        }
}

void
AutomationLine::track_entered()
{
        add_visibility (ControlPoints);
}

void
AutomationLine::track_exited()
{
        remove_visibility (ControlPoints);
}

XMLNode &
AutomationLine::get_state (void)
{
        /* function as a proxy for the model */
        return alist->get_state();
}

int
AutomationLine::set_state (const XMLNode &node, int version)
{
        /* function as a proxy for the model */
        return alist->set_state (node, version);
}

void
AutomationLine::view_to_model_coord (double& x, double& y) const
{
        x = _time_converter->from (x);
        view_to_model_coord_y (y);
}

void
AutomationLine::view_to_model_coord_y (double& y) const
{
        /* TODO: This should be more generic (use ParameterDescriptor)
         * or better yet:  Controllable -> set_interface();
         */
        if (   alist->parameter().type() == GainAutomation
            || alist->parameter().type() == EnvelopeAutomation
            || (_desc.unit == ParameterDescriptor::DB && _desc.lower == 0.)) {
                y = slider_position_to_gain_with_max (y, _desc.upper);
                y = max ((double)_desc.lower, y);
                y = min ((double)_desc.upper, y);
        } else if (alist->parameter().type() == TrimAutomation
                   || (_desc.unit == ParameterDescriptor::DB && _desc.lower > 0 && _desc.upper > _desc.lower)) {
                const double lower_db = accurate_coefficient_to_dB (_desc.lower);
                const double range_db = accurate_coefficient_to_dB (_desc.upper) - lower_db;
                y = max (0.0, y);
                y = min (1.0, y);
                y = dB_to_coefficient (lower_db + y * range_db);
        } else if (alist->parameter().type() == PanAzimuthAutomation ||
                   alist->parameter().type() == PanElevationAutomation) {
                y = 1.0 - y;
        } else if (alist->parameter().type() == PanWidthAutomation) {
                y = 2.0 * y - 1.0;
        } else {
                y = y * (double)(alist->get_max_y() - alist->get_min_y()) + alist->get_min_y();
                if (_desc.integer_step) {
                        y = round(y);
                } else if (_desc.toggled) {
                        y = (y > 0.5) ? 1.0 : 0.0;
                }
        }
}

void
AutomationLine::model_to_view_coord_y (double& y) const
{
        /* TODO: This should be more generic (use ParameterDescriptor) */
        if (   alist->parameter().type() == GainAutomation
            || alist->parameter().type() == EnvelopeAutomation
            || (_desc.unit == ParameterDescriptor::DB && _desc.lower == 0.)) {
                y = gain_to_slider_position_with_max (y, Config->get_max_gain());
        } else if (alist->parameter().type() == TrimAutomation
                   || (_desc.unit == ParameterDescriptor::DB && _desc.lower > 0 && _desc.upper > _desc.lower)) {
                const double lower_db = accurate_coefficient_to_dB (_desc.lower);
                const double range_db = accurate_coefficient_to_dB (_desc.upper) - lower_db;
                y = (accurate_coefficient_to_dB (y) - lower_db) / range_db;
        } else if (alist->parameter().type() == PanAzimuthAutomation ||
                   alist->parameter().type() == PanElevationAutomation) {
                y = 1.0 - y;
        } else if (alist->parameter().type() == PanWidthAutomation) {
                y = .5 + y * .5;
        } else {
                y = (y - alist->get_min_y()) / (double)(alist->get_max_y() - alist->get_min_y());
        }
}

void
AutomationLine::model_to_view_coord (double& x, double& y) const
{
        model_to_view_coord_y (y);
        x = _time_converter->to (x) - _offset;
}

void
AutomationLine::interpolation_changed (AutomationList::InterpolationStyle style)
{
        if (line_points.size() > 1) {
                line->set_steps(line_points, is_stepped());
        }
}

void
AutomationLine::add_visible_control_point (uint32_t view_index, uint32_t pi, double tx, double ty, 
                                           AutomationList::iterator model, uint32_t npoints)
{
        ControlPoint::ShapeType shape;

        if (view_index >= control_points.size()) {

                /* make sure we have enough control points */

                ControlPoint* ncp = new ControlPoint (*this);
                ncp->set_size (control_point_box_size ());

                control_points.push_back (ncp);
        }

        if (!terminal_points_can_slide) {
                if (pi == 0) {
                        control_points[view_index]->set_can_slide (false);
                        if (tx == 0) {
                                shape = ControlPoint::Start;
                        } else {
                                shape = ControlPoint::Full;
                        }
                } else if (pi == npoints - 1) {
                        control_points[view_index]->set_can_slide (false);
                        shape = ControlPoint::End;
                } else {
                        control_points[view_index]->set_can_slide (true);
                        shape = ControlPoint::Full;
                }
        } else {
                control_points[view_index]->set_can_slide (true);
                shape = ControlPoint::Full;
        }

        control_points[view_index]->reset (tx, ty, model, view_index, shape);

        /* finally, control visibility */

        if (_visible & ControlPoints) {
                control_points[view_index]->show ();
        } else {
                control_points[view_index]->hide ();
        }
}

void
AutomationLine::connect_to_list ()
{
        _list_connections.drop_connections ();

        alist->StateChanged.connect (_list_connections, invalidator (*this), boost::bind (&AutomationLine::list_changed, this), gui_context());

        alist->InterpolationChanged.connect (
                _list_connections, invalidator (*this), boost::bind (&AutomationLine::interpolation_changed, this, _1), gui_context());
}

MementoCommandBinder<AutomationList>*
AutomationLine::memento_command_binder ()
{
        return new SimpleMementoCommandBinder<AutomationList> (*alist.get());
}

void
AutomationLine::set_maximum_time (framecnt_t t)
{
        if (_maximum_time == t) {
                return;
        }

        _maximum_time = t;
        reset ();
}


pair<framepos_t, framepos_t>
AutomationLine::get_point_x_range () const
{
        pair<framepos_t, framepos_t> r (max_framepos, 0);

        for (AutomationList::const_iterator i = the_list()->begin(); i != the_list()->end(); ++i) {
                r.first = min (r.first, session_position (i));
                r.second = max (r.second, session_position (i));
        }

        return r;
}

framepos_t
AutomationLine::session_position (AutomationList::const_iterator p) const
{
        return _time_converter->to ((*p)->when) + _offset + _time_converter->origin_b ();
}

void
AutomationLine::set_offset (framepos_t off)
{
        if (_offset == off) {
                return;
        }

        _offset = off;
        reset ();
}