comparison view/LayerGeometryProvider.h @ 916:94e4952a6774 osx-retina

Start trying to introduce LayerGeometryProvider as proxyable interface for View methods that the Layer wants to use

+/* -*- 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 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 LAYER_GEOMETRY_PROVIDER_H
+#define LAYER_GEOMETRY_PROVIDER_H
+
+#include "base/BaseTypes.h"
+
+class ViewManager;
+class Layer;
+
+class LayerGeometryProvider
+{
+public:
+    /**
+     * 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.
+     */
+    virtual sv_frame_t getStartFrame() const = 0;
+
+    /**
+     * 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.
+     */
+    virtual sv_frame_t getCentreFrame() const = 0;
+
+    /**
+     * Retrieve the last visible sample frame on the widget.
+     * This is a calculated value based on the centre-frame, widget
+     * width and zoom level.
+     */
+    virtual sv_frame_t getEndFrame() const = 0;
+
+    /**
+     * Return the pixel x-coordinate corresponding to a given sample
+     * frame (which may be negative).
+     */
+    virtual int getXForFrame(sv_frame_t frame) const = 0;
+
+    /**
+     * Return the closest frame to the given pixel x-coordinate.
+     */
+    virtual sv_frame_t getFrameForX(int x) const = 0;
+
+    /**
+     * 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.
+     */
+    virtual double getYForFrequency(double frequency, double minFreq, double maxFreq, 
+                                    bool logarithmic) const = 0;
+
+    /**
+     * 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.
+     */
+    virtual double getFrequencyForY(int y, double minFreq, double maxFreq,
+			   bool logarithmic) const = 0;
+
+    /**
+     * Return the zoom level, i.e. the number of frames per pixel
+     */
+    virtual int getZoomLevel() const = 0;
+
+    /**
+     * 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).
+     */
+    virtual QRect getPaintRect() const = 0;
+
+    virtual QSize getPaintSize() const { return getPaintRect().size(); }
+    virtual int getPaintWidth() const { return getPaintRect().width(); }
+    virtual int getPaintHeight() const { return getPaintRect().height(); }
+
+    virtual bool hasLightBackground() const = 0;
+    virtual QColor getForeground() const = 0;
+    virtual QColor getBackground() const = 0;
+
+    virtual ViewManager *getViewManager() const = 0;
+
+    virtual bool shouldIlluminateLocalFeatures(const Layer *, QPoint &) const = 0;
+
+    enum TextStyle {
+	BoxedText,
+	OutlinedText,
+        OutlinedItalicText
+    };
+
+    virtual void drawVisibleText(QPainter &p, int x, int y,
+				 QString text, TextStyle style) const = 0;
+
+    virtual void drawMeasurementRect(QPainter &p, const Layer *,
+                                     QRect rect, bool focus) const = 0;
+
+    virtual QWidget *getWidget() const = 0;
+};
+
+#endif