LUMIERA.clone/src/gui/widgets/timeline/timeline-zoom-scale.cpp
2011-10-23 04:45:10 -05:00

156 lines
4.6 KiB
C++

/*
timeline-zoom-scale.cpp - Implementation of the zoom scale widget
Copyright (C) Lumiera.org
2011, Michael R. Fisher <mfisher31@gmail.com>
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 "gui/widgets/timeline-widget.hpp"
#include "gui/widgets/timeline/timeline-zoom-scale.hpp"
using namespace Gtk;
namespace gui {
namespace widgets {
class TimelineWidget;
namespace timeline {
/**
* @todo The initial adjustment value needs to
* match what the TimelineViewWindow's actual timeScale
* Value is. TimelineViewWindow::get_time_scale() is
* currently a public method, but will soon be private.
* Maybe TimelineViewWindow can have a zoom_adjustment
* that gets passed to this widget's Constructor?
*
* @todo actually there is a more involved problem.
* The TimelineWidget maintains a TimelineState, which in turn
* owns the TimelineViewWindow. Now, the problem is: when we
* switch to another Sequence (View), then this TimelineState
* gets switched too, causing also a entirely different TimelineViewWindow
* to become effective. Thus
* - how can we managed to be notified from that switch?
* - problem is: TimelineZoomScale widget is owned by the TimelinePannel.
* Likewise, TimelineWidget is owned by the TimelinePannel. But the
* state handling/switching logic is embedded within TimelineWidget
* - and finally: how can we translate the actual scale (in time units),
* as maintained within TimelineViewWindow, back into the adjustment
* used here (which uses a relative scale 0...1.0 )
*
*/
TimelineZoomScale::TimelineZoomScale()
: HBox()
, adjustment(0.5, 0.0, 1.0, 0.000001)
, slider()
, zoomIn(Stock::ZOOM_IN)
, zoomOut(Stock::ZOOM_OUT)
, button_step_size(0.03)
{
/* Setup the Slider Control */
slider.set_adjustment (adjustment);
slider.set_size_request (123,10);
slider.set_digits (6);
/* Inverted because smaller values "zoom in" */
slider.set_inverted (true);
slider.set_draw_value (false);
/* Make our connections */
zoomIn.signal_clicked().
connect (sigc::mem_fun(this, &TimelineZoomScale::on_zoom_in_clicked));
zoomOut.signal_clicked().
connect (sigc::mem_fun(this, &TimelineZoomScale::on_zoom_out_clicked));
adjustment.signal_value_changed().
connect (sigc::mem_fun(this, &TimelineZoomScale::on_zoom));
/* Add Our Widgets and show them */
pack_start (zoomOut,PACK_SHRINK);
pack_start (slider,PACK_SHRINK);
pack_start (zoomIn,PACK_SHRINK);
show_all();
}
void
TimelineZoomScale::wireTimelineState (shared_ptr<TimelineState> currentState,
TimelineWidget::TimelineStateChangeSignal stateChangeSignal)
{
on_timeline_state_changed (currentState);
stateChangeSignal.connect (
sigc::mem_fun(this, &TimelineZoomScale::on_timeline_state_changed));
}
void
TimelineZoomScale::on_timeline_state_changed (shared_ptr<TimelineState> newState)
{
REQUIRE (newState);
timelineState = newState;
int64_t current_scale =
getViewWindow().get_time_scale();
double linear_scale =
(double) current_scale / (double) TimelineWidget::MaxScale;
/* We have to Revese the Smoothing */
double new_relative_scale =
pow(linear_scale,(1.0 / TimelineWidget::ZoomSmoothing));
adjustment.set_value(new_relative_scale);
}
void
TimelineZoomScale::on_zoom_in_clicked()
{
double newValue = adjustment.get_value() - button_step_size;
adjustment.set_value(newValue);
}
void
TimelineZoomScale::on_zoom_out_clicked()
{
double newValue = adjustment.get_value() + button_step_size;
adjustment.set_value(newValue);
}
void
TimelineZoomScale::on_zoom()
{
zoomSignal.emit (adjustment.get_value()) ;
}
sigc::signal<void, double>
TimelineZoomScale::signal_zoom()
{
return zoomSignal;
}
TimelineViewWindow&
TimelineZoomScale::getViewWindow()
{
REQUIRE (timelineState, "lifecycle error");
return timelineState->get_view_window();
}
} // namespace gui
} // namespace widgets
} // namespace timeline