Mercurial > hg > svcore
diff base/RangeMapper.h @ 880:b4787b595db3
Implement and test the interpolating and auto range mappers
author | Chris Cannam |
---|---|
date | Fri, 31 Jan 2014 17:09:02 +0000 |
parents | eb6b6a88faed |
children | 12a6140b3ae0 |
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--- a/base/RangeMapper.h Fri Jan 31 13:39:37 2014 +0000 +++ b/base/RangeMapper.h Fri Jan 31 17:09:02 2014 +0000 @@ -19,7 +19,7 @@ #include <QString> #include "Debug.h" - +#include <map> class RangeMapper { @@ -58,10 +58,16 @@ bool m_inverted; }; - class LogRangeMapper : public RangeMapper { public: + /** + * Map values in range minval->maxval into integer range + * minpos->maxpos such that logs of the values are mapped + * linearly. minval and minpos must be less than maxval and maxpos + * respectively. If inverted is true, the range will be mapped + * "backwards" (minval to maxpos and maxval to minpos). + */ LogRangeMapper(int minpos, int maxpos, float minval, float maxval, QString m_unit = "", bool inverted = false); @@ -89,5 +95,111 @@ bool m_inverted; }; +class InterpolatingRangeMapper : public RangeMapper +{ +public: + typedef std::map<float, int> CoordMap; + + /** + * Given a series of (value, position) coordinate mappings, + * construct a range mapper that maps arbitrary values, in the + * range between minimum and maximum of the provided values, onto + * coordinates using linear interpolation between the supplied + * points. + * + *!!! todo: Cubic -- more generally useful than linear interpolation + *!!! todo: inverted flag + * + * The set of provided mappings must contain at least two + * coordinates. + * + * It is expected that the values and positions in the coordinate + * mappings will both be monotonically increasing (i.e. no + * inflections in the mapping curve). Behaviour is undefined if + * this is not the case. + */ + InterpolatingRangeMapper(CoordMap pointMappings, + QString unit); + + virtual int getPositionForValue(float value) const; + virtual float getValueForPosition(int position) const; + + virtual QString getUnit() const { return m_unit; } + +protected: + CoordMap m_mappings; + std::map<int, float> m_reverse; + QString m_unit; +}; + +class AutoRangeMapper : public RangeMapper +{ +public: + enum MappingType { + Interpolating, + StraightLine, + Logarithmic, + }; + + typedef std::map<float, int> CoordMap; + + /** + * Given a series of (value, position) coordinate mappings, + * construct a range mapper that maps arbitrary values, in the + * range between minimum and maximum of the provided values, onto + * coordinates. + * + * The mapping used may be + * + * Interpolating -- an InterpolatingRangeMapper will be used + * + * StraightLine -- a LinearRangeMapper from the minimum to + * maximum value coordinates will be used, ignoring all other + * supplied coordinate mappings + * + * Logarithmic -- a LogRangeMapper from the minimum to + * maximum value coordinates will be used, ignoring all other + * supplied coordinate mappings + * + * The mapping will be chosen automatically by looking at the + * supplied coordinates. If the supplied coordinates fall on a + * straight line, a StraightLine mapping will be used; if they + * fall on a log curve, a Logarithmic mapping will be used; + * otherwise an Interpolating mapping will be used. + * + *!!! todo: inverted flag + * + * The set of provided mappings must contain at least two + * coordinates, or at least three if the points are not supposed + * to be in a straight line. + * + * It is expected that the values and positions in the coordinate + * mappings will both be monotonically increasing (i.e. no + * inflections in the mapping curve). Behaviour is undefined if + * this is not the case. + */ + AutoRangeMapper(CoordMap pointMappings, + QString unit); + + ~AutoRangeMapper(); + + /** + * Return the mapping type in use. + */ + MappingType getType() const { return m_type; } + + virtual int getPositionForValue(float value) const; + virtual float getValueForPosition(int position) const; + + virtual QString getUnit() const { return m_unit; } + +protected: + MappingType m_type; + CoordMap m_mappings; + QString m_unit; + RangeMapper *m_mapper; + + MappingType chooseMappingTypeFor(const CoordMap &); +}; #endif