comparison base/MagnitudeRange.h @ 1186:12a8daa89970 spectrogram-minor-refactor

Mid-refactor to pull out the bulk of paintDrawBuffer into chunks

+/* -*- 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 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 MAGNITUDE_RANGE_H
+#define MAGNITUDE_RANGE_H
+
+/**
+ * Maintain a min and max value, and update them when supplied a new
+ * data point.
+ */
+class MagnitudeRange
+{
+public:
+    MagnitudeRange() : m_min(0), m_max(0) { }
+    bool operator==(const MagnitudeRange &r) {
+	return r.m_min == m_min && r.m_max == m_max;
+    }
+    bool isSet() const { return (m_min != 0.f || m_max != 0.f); }
+    void set(float min, float max) {
+	m_min = min;
+	m_max = max;
+	if (m_max < m_min) m_max = m_min;
+    }
+    bool sample(float f) {
+	bool changed = false;
+	if (isSet()) {
+	    if (f < m_min) { m_min = f; changed = true; }
+	    if (f > m_max) { m_max = f; changed = true; }
+	} else {
+	    m_max = m_min = f;
+	    changed = true;
+	}
+	return changed;
+    }            
+    bool sample(const MagnitudeRange &r) {
+	bool changed = false;
+	if (isSet()) {
+	    if (r.m_min < m_min) { m_min = r.m_min; changed = true; }
+	    if (r.m_max > m_max) { m_max = r.m_max; changed = true; }
+	} else {
+	    m_min = r.m_min;
+	    m_max = r.m_max;
+	    changed = true;
+	}
+	return changed;
+    }            
+    float getMin() const { return m_min; }
+    float getMax() const { return m_max; }
+private:
+    float m_min;
+    float m_max;
+};
+
+#endif