diff layer/VerticalBinLayer.h @ 1082:5b4fe7bb9430 spectrogram-minor-refactor

VerticalBinLayer for vertical mapping abstraction. Not totally sure about this

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/layer/VerticalBinLayer.h	Fri Jul 01 09:55:48 2016 +0100
@@ -0,0 +1,54 @@
+/* -*- 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 2006-2016 Chris Cannam and 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 VERTICAL_BIN_LAYER_H
+#define VERTICAL_BIN_LAYER_H
+
+/**
+ * Interface for layers in which the Y axis corresponds to bin number
+ * rather than scale value. Colour3DPlotLayer is the obvious example.
+ */
+class VerticalBinLayer
+{
+public:
+    /**
+     * Return the y coordinate at which the given bin "starts"
+     * (i.e. at the bottom of the bin, if the given bin is an integer
+     * and the vertical scale is the usual way up). Bin number may be
+     * fractional, to obtain a position part-way through a bin.
+     */
+    virtual double getYForBin(LayerGeometryProvider *, double bin) const = 0;
+
+    /**
+     * As getYForBin, but rounding to integer values.
+     */
+    virtual int getIYForBin(LayerGeometryProvider *, int bin) const = 0;
+    
+    /**
+     * Return the bin number, possibly fractional, at the given y
+     * coordinate. Note that the whole numbers occur at the positions
+     * at which the bins "start" (i.e. the bottom of the visible bin,
+     * if the vertical scale is the usual way up).
+     */
+    virtual double getBinForY(LayerGeometryProvider *, double y) const = 0;
+
+    /**
+     * As getBinForY, but rounding to integer values.
+     */
+    virtual int getIBinForY(LayerGeometryProvider *, int y) const = 0;
+};
+
+#endif
+