qwt3d_scale.h

#ifndef qwt3d_scale_h__2004_06_02_22_02_begin_guarded_code
#define qwt3d_scale_h__2004_06_02_22_02_begin_guarded_code

#include <qstring.h>
#include "qwt3d_types.h"
#include "qwt3d_autoscaler.h"
#include "qwt3d_autoptr.h"

namespace Qwt3D
{

/*! 
The class encapsulates non-visual scales. 
She is utilized by Axis and also collaborates closely with AutoScaler.
A Scale allows control over all aspects of tic generation including 
arbitrary transformations of tic values into corresponding strings. 
The strings contain what eventually will be shown as tic labels.\n
Standard linear and logarithmic scales have been integrated yet into the Axis 
interface. User-defined axes can be derived from Scale, LinearScale et al.
*/
class QWT3D_EXPORT Scale
{
  friend class Axis;
  friend class qwt3d_ptr<Scale>;

  protected:
    Scale();
    virtual ~Scale(){}
    virtual QString ticLabel(unsigned int idx) const;

    virtual void setLimits(double start, double stop); 
    virtual void setMajors(int val) {majorintervals_p=val;} //!< Sets number of major intervals
    virtual void setMinors(int val) {minorintervals_p=val;} //!< Sets number of minor intervals per major interval
    virtual void setMajorLimits(double start, double stop);

    int majors() const {return majorintervals_p;} //!< Returns major intervals
    int minors() const {return minorintervals_p;} //!< Returns minor intervals

    //! Derived classes should return a new heap based object here.  
    virtual Scale* clone() const = 0;
    //! This function should setup the 2 vectors for major and minor positions;
    virtual void calculate() = 0;
    virtual int autoscale(double& a, double& b, double start, double stop, int ivals);

    std::vector<double> majors_p, minors_p; 
    double start_p, stop_p;
    int majorintervals_p, minorintervals_p;
    double mstart_p, mstop_p;
  
  private:
    void destroy() const {delete this;} //!< Used by qwt3d_ptr   
};

//! The standard (1:1) mapping class for axis numbering
class QWT3D_EXPORT LinearScale : public Scale
{
  friend class Axis;
  friend class qwt3d_ptr<Scale>;
protected:
  int autoscale(double& a, double& b, double start, double stop, int ivals);
  //! Returns a new heap based object utilized from qwt3d_ptr
  Scale* clone() const {return new LinearScale(*this);}
  void calculate();
  LinearAutoScaler autoscaler_p;
};

//! log10 scale
class QWT3D_EXPORT LogScale : public Scale
{
  friend class Axis;
  friend class qwt3d_ptr<Scale>;
protected:
  QString ticLabel(unsigned int idx) const;
  void setMinors(int val);
  //! Standard ctor
  LogScale();
  //! Returns a new heap based object utilized from qwt3d_ptr
  Scale* clone() const {return new LogScale;}
  void calculate();
private:
  void setupCounter(double& k, int& step);
};

} // namespace Qwt3D


#endif /* include guarded */