annotate layer/SingleColourLayer.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 2007 QMUL.
    
    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 _SINGLE_COLOUR_LAYER_H_
#define _SINGLE_COLOUR_LAYER_H_

#include "Layer.h"
#include <QColor>
#include <vector>
#include <map>

class SingleColourLayer : public Layer
{
    Q_OBJECT
    
public:
    /**
     * Set the colour used to draw primary items in the layer. The
     * colour value is a colour database index as returned by
     * ColourDatabase::getColourIndex().
     */
    virtual void setBaseColour(int);

    /**
     * Retrieve the current primary drawing colour, as a
     * ColourDatabase index value.
     */
    virtual int getBaseColour() const;

    /**
     * Return true if the layer currently has a dark colour on a light
     * background, false if it has a light colour on a dark
     * background.
     */
    virtual bool hasLightBackground() const;

    /**
     * Implements Layer::getLayerColourSignificance()
     */
    virtual ColourSignificance getLayerColourSignificance() const {
        return ColourDistinguishes;
    }

    virtual QPixmap getLayerPresentationPixmap(QSize size) const;

    virtual PropertyList getProperties() const;
    virtual QString getPropertyLabel(const PropertyName &) const;
    virtual PropertyType getPropertyType(const PropertyName &) const;
    virtual QString getPropertyGroupName(const PropertyName &) const;
    virtual int getPropertyRangeAndValue(const PropertyName &,
                                         int *min, int *max, int *deflt) const;
    virtual QString getPropertyValueLabel(const PropertyName &,
					  int value) const;
    virtual RangeMapper *getNewPropertyRangeMapper(const PropertyName &) const;
    virtual void setProperty(const PropertyName &, int value);

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

    virtual void setProperties(const QXmlAttributes &attributes);

    virtual void setDefaultColourFor(LayerGeometryProvider *v);

protected:
    SingleColourLayer();
    virtual ~SingleColourLayer();

    virtual QColor getBaseQColor() const;
    virtual QColor getBackgroundQColor(LayerGeometryProvider *v) const;
    virtual QColor getForegroundQColor(LayerGeometryProvider *v) const;
    std::vector<QColor> getPartialShades(LayerGeometryProvider *v) const;

    virtual void flagBaseColourChanged() { }
    virtual int getDefaultColourHint(bool /* darkBackground */,
                                     bool & /* impose */) { return -1; }

    typedef std::map<int, int> ColourRefCount;
    static ColourRefCount m_colourRefCount;

    int m_colour;
    bool m_colourExplicitlySet;
    bool m_defaultColourSet;

private:
    void refColor();
    void unrefColor();
};

#endif