comparison layer/HorizontalScaleProvider.h @ 1282:f90a3c2f2930

Merge from branch horizontal-scale

+/* -*- 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 2006-2018 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 SV_HORIZONTAL_SCALE_PROVIDER_H
+#define SV_HORIZONTAL_SCALE_PROVIDER_H
+
+class LayerGeometryProvider;
+
+/**
+ * Interface to be implemented by objects, such as layers or objects
+ * they delegate to, in which the X axis corresponds to frequency. For
+ * example, SpectrumLayer.
+ */
+class HorizontalScaleProvider
+{
+public:
+    virtual double getFrequencyForX(const LayerGeometryProvider *,
+                                    double x)
+        const = 0;
+    
+    virtual double getXForFrequency(const LayerGeometryProvider *,
+                                    double freq)
+        const = 0;
+};
+
+#endif