// -*- Mode: c++ -*-
#ifndef	__UISTATE_H__
#define	__UISTATE_H__

// include files
#include <assert.h>

// class definition
// pointer to function taking void returning void
typedef void ( *vFv )( void );

// so ... this class is a bit weird. It has no members but statics. Thus it
// really is just a device to create a lexical scope for a number of things
// associated with the ui.
// this can be done with namespaces in recent versions of C++ compilers

class UIState{
public:
  static const int UNDEF;
  // since there never is an object of this kind, none of the standard
  // functions are there.
  
  // accessors
  static vFv&   Animate( void ) { return p_animate; }
  static float& Angle( void ) { return p_angle; }
  static float& AngleIncr( void ) { return p_angle_incr; }
  static int&   MouseX( void ) { return p_mousex; }
  static int&   MouseY( void ) { return p_mousey; }
  static float& TransX( void ) { return p_transx; }
  static float& TransY( void ) { return p_transy; }
  
  // methods
  static void ResetModelTransform( void );
  static void ApplyModelTransform( void );
protected:
private:
  // last know mouse position
  static int p_mousex, p_mousey;
  // animation function pointer
  static void ( *p_animate )( void );
  // state variable for animation
  static float p_angle_incr;

  // state variable for rotation
  static float p_angle;

  // state variables for translation
  static float p_transx, p_transy;
  
  // can't make it, can't destroy it, and sure can't do anything else...
  // to make sure that it is not done accidentally,
  // abort the program when the constructor or destructor are called
  UIState( void ) { assert( 0 ); }
  ~UIState( void ) { assert( 0 ); }
};

#endif	/* __UISTATE_H__ */