view view/View.h @ 1127:9fb8dfd7ce4c spectrogram-minor-refactor

Fix threshold in spectrogram -- it wasn't working in the last release.
There is a new protocol for this. Formerly the threshold parameter had a
range from -50dB to 0 with the default at -50, and -50 treated internally
as "no threshold". However, there was a hardcoded, hidden internal threshold
for spectrogram colour mapping at -80dB with anything below this being rounded
to zero. Now the threshold parameter has range -81 to -1 with the default
at -80, -81 is treated internally as "no threshold", and there is no hidden
internal threshold. So the default behaviour is the same as before, an
effective -80dB threshold, but it is now possible to change this in both
directions. Sessions reloaded from prior versions may look slightly different
because, if the session says there should be no threshold, there will now
actually be no threshold instead of having the hidden internal one.

Still need to do something in the UI to make it apparent that the -81dB
setting removes the threshold entirely. This is at least no worse than the
previous, also obscured, magic -50dB setting.

/* -*- c-basic-offset: 4 indent-tabs-mode: nil -*-  vi:set ts=8 sts=4 sw=4: */

/*
    Sonic Visualiser
    An audio file viewer and annotation editor.
    Centre for Digital Music, Queen Mary, University of London.
    This file copyright 2006 Chris Cannam.
    
    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.  See the file
    COPYING included with this distribution for more information.
*/

#ifndef _VIEW_H_
#define _VIEW_H_

#include <QFrame>
#include <QProgressBar>

#include "layer/LayerGeometryProvider.h"

#include "base/ZoomConstraint.h"
#include "base/PropertyContainer.h"
#include "ViewManager.h"
#include "base/XmlExportable.h"
#include "base/BaseTypes.h"

// #define DEBUG_VIEW_WIDGET_PAINT 1

class Layer;
class ViewPropertyContainer;

class QPushButton;

#include <map>
#include <set>

/**
 * View is the base class of widgets that display one or more
 * overlaid views of data against a horizontal time scale. 
 *
 * A View may have any number of attached Layers, each of which
 * is expected to have one data Model (although multiple views may
 * share the same model).
 *
 * A View may be panned in time and zoomed, although the
 * mechanisms for doing so (as well as any other operations and
 * properties available) depend on the subclass.
 */

class View : public QFrame,
	     public XmlExportable,
             public LayerGeometryProvider
{
    Q_OBJECT

public:
    /**
     * Deleting a View does not delete any of its layers.  They should
     * be managed elsewhere (e.g. by the Document).
     */
    virtual ~View();

    /**
     * Retrieve the id of this object. Views have their own unique
     * ids, but ViewProxy objects share the id of their View.
     */
    int getId() const { return m_id; }
    
    /**
     * Retrieve the first visible sample frame on the widget.
     * This is a calculated value based on the centre-frame, widget
     * width and zoom level.  The result may be negative.
     */
    sv_frame_t getStartFrame() const;

    /**
     * Set the widget pan based on the given first visible frame.  The
     * frame value may be negative.
     */
    void setStartFrame(sv_frame_t);

    /**
     * Return the centre frame of the visible widget.  This is an
     * exact value that does not depend on the zoom block size.  Other
     * frame values (start, end) are calculated from this based on the
     * zoom and other factors.
     */
    sv_frame_t getCentreFrame() const { return m_centreFrame; }

    /**
     * Set the centre frame of the visible widget.
     */
    void setCentreFrame(sv_frame_t f) { setCentreFrame(f, true); }

    /**
     * Retrieve the last visible sample frame on the widget.
     * This is a calculated value based on the centre-frame, widget
     * width and zoom level.
     */
    sv_frame_t getEndFrame() const;

    /**
     * Return the pixel x-coordinate corresponding to a given sample
     * frame (which may be negative).
     */
    int getXForFrame(sv_frame_t frame) const;

    /**
     * Return the closest frame to the given pixel x-coordinate.
     */
    sv_frame_t getFrameForX(int x) const;

    /**
     * Return the closest pixel x-coordinate corresponding to a given
     * view x-coordinate. Default is no scaling, ViewProxy handles
     * scaling case.
     */
    int getXForViewX(int viewx) const { return viewx; }

    /**
     * Return the closest view x-coordinate corresponding to a given
     * pixel x-coordinate. Default is no scaling, ViewProxy handles
     * scaling case.
     */
    int getViewXForX(int x) const { return x; }

    /**
     * Return the pixel y-coordinate corresponding to a given
     * frequency, if the frequency range is as specified.  This does
     * not imply any policy about layer frequency ranges, but it might
     * be useful for layers to match theirs up if desired.
     *
     * Not thread-safe in logarithmic mode.  Call only from GUI thread.
     */
    double getYForFrequency(double frequency, double minFreq, double maxFreq, 
			   bool logarithmic) const;

    /**
     * Return the closest frequency to the given pixel y-coordinate,
     * if the frequency range is as specified.
     *
     * Not thread-safe in logarithmic mode.  Call only from GUI thread.
     */
    double getFrequencyForY(double y, double minFreq, double maxFreq,
                            bool logarithmic) const;

    /**
     * Return the zoom level, i.e. the number of frames per pixel
     */
    int getZoomLevel() const;

    /**
     * Set the zoom level, i.e. the number of frames per pixel.  The
     * centre frame will be unchanged; the start and end frames will
     * change.
     */
    virtual void setZoomLevel(int z);

    /**
     * Zoom in or out.
     */
    virtual void zoom(bool in);

    /**
     * Scroll left or right by a smallish or largish amount.
     */
    virtual void scroll(bool right, bool lots, bool doEmit = true);

    /**
     * Add a layer to the view. (Normally this should be handled
     * through some command abstraction instead of using this function
     * directly.)
     */
    virtual void addLayer(Layer *v);

    /**
     * Remove a layer from the view. Does not delete the
     * layer. (Normally this should be handled through some command
     * abstraction instead of using this function directly.)
     */
    virtual void removeLayer(Layer *v);

    /**
     * Return the number of layers, regardless of whether visible or
     * dormant, i.e. invisible, in this view.
     */
    virtual int getLayerCount() const { return int(m_layerStack.size()); }

    /**
     * Return the nth layer, counted in stacking order.  That is,
     * layer 0 is the bottom layer and layer "getLayerCount()-1" is
     * the top one. The returned layer may be visible or it may be
     * dormant, i.e. invisible.
     */
    virtual Layer *getLayer(int n) {
        if (in_range_for(m_layerStack, n)) return m_layerStack[n];
        else return 0;
    }

    /**
     * Return the nth layer, counted in the order they were
     * added. Unlike the stacking order used in getLayer(), which
     * changes each time a layer is selected, this ordering remains
     * fixed. The returned layer may be visible or it may be dormant,
     * i.e. invisible.
     */
    virtual Layer *getFixedOrderLayer(int n) {
        if (n < int(m_fixedOrderLayers.size())) return m_fixedOrderLayers[n];
        else return 0;
    }

    /**
     * Return the layer currently active for tool interaction. This is
     * the topmost non-dormant (i.e. visible) layer in the view. If
     * there are no visible layers in the view, return 0.
     */
    virtual Layer *getInteractionLayer();

    virtual const Layer *getInteractionLayer() const;

    /**
     * Return the layer most recently selected by the user. This is
     * the layer that any non-tool-driven commands should operate on,
     * in the case where this view is the "current" one.
     *
     * If the user has selected the view itself more recently than any
     * of the layers on it, this function will return 0, and any
     * non-tool-driven layer commands should be deactivated while this
     * view is current. It will also return 0 if there are no layers
     * in the view.
     *
     * Note that, unlike getInteractionLayer(), this could return an
     * invisible (dormant) layer.
     */
    virtual Layer *getSelectedLayer();

    virtual const Layer *getSelectedLayer() const;

    /**
     * Return the "top" layer in the view, whether visible or dormant.
     * This is the same as getLayer(getLayerCount()-1) if there is at
     * least one layer, and 0 otherwise.
     *
     * For most purposes involving interaction or commands, you
     * probably want either getInteractionLayer() or
     * getSelectedLayer() instead.
     */
    virtual Layer *getTopLayer() {
        return m_layerStack.empty() ? 0 : m_layerStack[m_layerStack.size()-1];
    }

    virtual void setViewManager(ViewManager *m);
    virtual void setViewManager(ViewManager *m, sv_frame_t initialFrame);
    virtual ViewManager *getViewManager() const { return m_manager; }

    virtual void setFollowGlobalPan(bool f);
    virtual bool getFollowGlobalPan() const { return m_followPan; }

    virtual void setFollowGlobalZoom(bool f);
    virtual bool getFollowGlobalZoom() const { return m_followZoom; }

    virtual bool hasLightBackground() const;
    virtual QColor getForeground() const;
    virtual QColor getBackground() const;

    virtual void drawMeasurementRect(QPainter &p, const Layer *,
                                     QRect rect, bool focus) const;

    virtual bool shouldShowFeatureLabels() const {
        return m_manager && m_manager->shouldShowFeatureLabels();
    }
    virtual bool shouldIlluminateLocalFeatures(const Layer *, QPoint &) const {
	return false;
    }
    virtual bool shouldIlluminateLocalSelection(QPoint &, bool &, bool &) const {
	return false;
    }

    virtual void setPlaybackFollow(PlaybackFollowMode m);
    virtual PlaybackFollowMode getPlaybackFollow() const { return m_followPlay; }

    typedef PropertyContainer::PropertyName PropertyName;

    // We implement the PropertyContainer API, although we don't
    // actually subclass PropertyContainer.  We have our own
    // PropertyContainer that we can return on request that just
    // delegates back to us.
    virtual PropertyContainer::PropertyList getProperties() const;
    virtual QString getPropertyLabel(const PropertyName &) const;
    virtual PropertyContainer::PropertyType getPropertyType(const PropertyName &) const;
    virtual int getPropertyRangeAndValue(const PropertyName &,
					 int *min, int *max, int *deflt) const;
    virtual QString getPropertyValueLabel(const PropertyName &,
					  int value) const;
    virtual void setProperty(const PropertyName &, int value);
    virtual QString getPropertyContainerName() const {
	return objectName();
    }
    virtual QString getPropertyContainerIconName() const = 0;

    virtual int getPropertyContainerCount() const;

    // The 0th property container is the view's own; the rest are the
    // layers in fixed-order series
    virtual const PropertyContainer *getPropertyContainer(int i) const;
    virtual PropertyContainer *getPropertyContainer(int i);

    // Render the contents on a wide canvas
    virtual QImage *toNewImage(sv_frame_t f0, sv_frame_t f1);
    virtual QImage *toNewImage();
    virtual QSize getImageSize(sv_frame_t f0, sv_frame_t f1);
    virtual QSize getImageSize();

    virtual int getTextLabelHeight(const Layer *layer, QPainter &) const;

    virtual bool getValueExtents(QString unit, double &min, double &max,
                                 bool &log) const;

    virtual void toXml(QTextStream &stream, QString indent = "",
                       QString extraAttributes = "") const;

    // First frame actually in model, to right of scale, if present
    virtual sv_frame_t getFirstVisibleFrame() const;
    virtual sv_frame_t getLastVisibleFrame() const;

    sv_frame_t getModelsStartFrame() const;
    sv_frame_t getModelsEndFrame() const;

    /**
     * To be called from a layer, to obtain the extent of the surface
     * that the layer is currently painting to. This may be the extent
     * of the view (if 1x display scaling is in effect) or of a larger
     * cached pixmap (if greater display scaling is in effect).
     */
    QRect getPaintRect() const;

    QSize getPaintSize() const { return getPaintRect().size(); }
    int getPaintWidth() const { return getPaintRect().width(); }
    int getPaintHeight() const { return getPaintRect().height(); }

    typedef std::set<Model *> ModelSet;
    ModelSet getModels();

    //!!!
    Model *getAligningModel() const;
    sv_frame_t alignFromReference(sv_frame_t) const;
    sv_frame_t alignToReference(sv_frame_t) const;
    sv_frame_t getAlignedPlaybackFrame() const;

    void updatePaintRect(QRect r) { update(r); }
    
    View *getView() { return this; } 
    const View *getView() const { return this; } 
    
signals:
    void propertyContainerAdded(PropertyContainer *pc);
    void propertyContainerRemoved(PropertyContainer *pc);
    void propertyContainerPropertyChanged(PropertyContainer *pc);
    void propertyContainerPropertyRangeChanged(PropertyContainer *pc);
    void propertyContainerNameChanged(PropertyContainer *pc);
    void propertyContainerSelected(PropertyContainer *pc);
    void propertyChanged(PropertyContainer::PropertyName);

    void layerModelChanged();

    void centreFrameChanged(sv_frame_t frame,
                            bool globalScroll,
                            PlaybackFollowMode followMode);

    void zoomLevelChanged(int level, bool locked);

    void contextHelpChanged(const QString &);

public slots:
    virtual void modelChanged();
    virtual void modelChangedWithin(sv_frame_t startFrame, sv_frame_t endFrame);
    virtual void modelCompletionChanged();
    virtual void modelAlignmentCompletionChanged();
    virtual void modelReplaced();
    virtual void layerParametersChanged();
    virtual void layerParameterRangesChanged();
    virtual void layerMeasurementRectsChanged();
    virtual void layerNameChanged();

    virtual void globalCentreFrameChanged(sv_frame_t);
    virtual void viewCentreFrameChanged(View *, sv_frame_t);
    virtual void viewManagerPlaybackFrameChanged(sv_frame_t);
    virtual void viewZoomLevelChanged(View *, int, bool);

    virtual void propertyContainerSelected(View *, PropertyContainer *pc);

    virtual void selectionChanged();
    virtual void toolModeChanged();
    virtual void overlayModeChanged();
    virtual void zoomWheelsEnabledChanged();

    virtual void cancelClicked();

    virtual void progressCheckStalledTimerElapsed();

protected:
    View(QWidget *, bool showProgress);

    int m_id;
    
    virtual void paintEvent(QPaintEvent *e);
    virtual void drawSelections(QPainter &);
    virtual bool shouldLabelSelections() const { return true; }
    virtual bool render(QPainter &paint, int x0, sv_frame_t f0, sv_frame_t f1);
    virtual void setPaintFont(QPainter &paint);

    QSize scaledSize(const QSize &s, int factor) {
        return QSize(s.width() * factor, s.height() * factor);
    }
    QRect scaledRect(const QRect &r, int factor) {
        return QRect(r.x() * factor, r.y() * factor,
                     r.width() * factor, r.height() * factor);
    }
    
    typedef std::vector<Layer *> LayerList;

    sv_samplerate_t getModelsSampleRate() const;
    bool areLayersScrollable() const;
    LayerList getScrollableBackLayers(bool testChanged, bool &changed) const;
    LayerList getNonScrollableFrontLayers(bool testChanged, bool &changed) const;
    int getZoomConstraintBlockSize(int blockSize,
				      ZoomConstraint::RoundingDirection dir =
				      ZoomConstraint::RoundNearest) const;

    // True if the top layer(s) use colours for meaningful things.  If
    // this is the case, selections will be shown using unfilled boxes
    // rather than with a translucent fill.
    bool areLayerColoursSignificant() const;

    // True if the top layer has a time axis on the x coordinate (this
    // is generally the case except for spectrum/slice layers).  It
    // will not be possible to make or display selections if this is
    // false.
    bool hasTopLayerTimeXAxis() const;

    bool setCentreFrame(sv_frame_t f, bool doEmit);

    void movePlayPointer(sv_frame_t f);

    void checkProgress(void *object);
    int getProgressBarWidth() const; // if visible

    int effectiveDevicePixelRatio() const;

    sv_frame_t          m_centreFrame;
    int                 m_zoomLevel;
    bool                m_followPan;
    bool                m_followZoom;
    PlaybackFollowMode  m_followPlay;
    bool                m_followPlayIsDetached;
    sv_frame_t          m_playPointerFrame;
    bool                m_lightBackground;
    bool                m_showProgress;

    QPixmap            *m_cache;
    QPixmap            *m_buffer;
    sv_frame_t          m_cacheCentreFrame;
    int                 m_cacheZoomLevel;
    bool                m_selectionCached;

    bool                m_deleting;

    LayerList           m_layerStack; // I don't own these, but see dtor note above
    LayerList           m_fixedOrderLayers;
    bool                m_haveSelectedLayer;

    QString             m_lastError;

    // caches for use in getScrollableBackLayers, getNonScrollableFrontLayers
    mutable LayerList m_lastScrollableBackLayers;
    mutable LayerList m_lastNonScrollableBackLayers;

    struct ProgressBarRec {
        QPushButton *cancel;
        QProgressBar *bar;
        int lastCheck;
        QTimer *checkTimer;
    };
    typedef std::map<Layer *, ProgressBarRec> ProgressMap;
    ProgressMap m_progressBars; // I own the ProgressBars

    ViewManager *m_manager; // I don't own this
    ViewPropertyContainer *m_propertyContainer; // I own this
};


// Use this for delegation, because we can't subclass from
// PropertyContainer (which is a QObject) ourselves because of
// ambiguity with QFrame parent

class ViewPropertyContainer : public PropertyContainer
{
    Q_OBJECT

public:
    ViewPropertyContainer(View *v);
    virtual ~ViewPropertyContainer();

    PropertyList getProperties() const { return m_v->getProperties(); }
    QString getPropertyLabel(const PropertyName &n) const {
        return m_v->getPropertyLabel(n);
    }
    PropertyType getPropertyType(const PropertyName &n) const {
	return m_v->getPropertyType(n);
    }
    int getPropertyRangeAndValue(const PropertyName &n, int *min, int *max,
                                 int *deflt) const {
	return m_v->getPropertyRangeAndValue(n, min, max, deflt);
    }
    QString getPropertyValueLabel(const PropertyName &n, int value) const {
	return m_v->getPropertyValueLabel(n, value);
    }
    QString getPropertyContainerName() const {
	return m_v->getPropertyContainerName();
    }
    QString getPropertyContainerIconName() const {
	return m_v->getPropertyContainerIconName();
    }

public slots:
    virtual void setProperty(const PropertyName &n, int value) {
	m_v->setProperty(n, value);
    }

protected:
    View *m_v;
};

#endif