|
/* (c) 1999-2000 Tino Schwarze, see COPYING for details */
/**@pkg cObject.cVisibleObject.cInteractiveObject.cLight.cSpotLight*/
/**
* a class for managing a directional OpenGL light
*
* #include "cSpotLight.hh"
*
* -lMesaGL or -lGL
*
* @see cInteractiveObject
* @see cLight
* @pkgdoc cObject.cVisibleObject.cInteractiveObject.cLight.cSpotLight
*/
#ifndef cSpotLight_hh
#define cSpotLight_hh
// include class cLight to derive from
#include "cLight.hh"
// include class cColor representing an RGB(A) color for use
// with OpenGL
#include "cADSEColor.hh"
// include common project macros, definitions and headers
#include "common.hh"
/**
* A class for an OpenGL directional light.
* The inherited mRotation quaternion is used (in contrast to cLight)
* - it modifies the light's direction.
*/
class cSpotLight
: public cLight
{
public:
/**
* default constructor
*/
cSpotLight (
cEventDispatcher *disp,
const char *name = NULL);
#if DEBUG
/**
* copy constructor (inherited)
*/
cSpotLight (const cSpotLight &);
#endif
/**
* constructor with initialization of position and name
* @param pos initial position of light source
* @param dir initial direction of light source
* @param state initial state of light source (default: on)
* @param name name of light source (optional)
*/
cSpotLight (
cEventDispatcher *disp,
const cVertex &pos,
const cVertex &dir,
const char *name = NULL);
/**
* constructor with initialization of position, state and name
* @param pos initial position of light source
* @param dir initial direction of light source
* @param state initial state of light source (default: on)
* @param name name of light source (optional)
*/
cSpotLight (
cEventDispatcher *disp,
const cVertex &pos,
const cVertex &dir,
const teLightState state = LIGHT_ON,
const char *name = NULL);
/**
* constructor with initialization of position, color, state
* and name
* @param dir initial direction of light source
* @param pos initial position of light source
* @param col color of the light source (cADSEColor object)
* (emissive color component is not used)
* @param state initial state of light source (default: on)
* @param name name of light source (optional)
*/
cSpotLight (
cEventDispatcher *disp,
const cVertex &pos,
const cVertex &dir,
const cADSEColor &col,
const teLightState state = LIGHT_ON,
const char *name = NULL);
/**
* destructor
*/
virtual ~cSpotLight ();
// OPERATIONS
// note: translating the light is obtained via functions inherited from
// cVisibleObject (@see cVisibleObject::MoveBy, cVisibleObject::MoveTo)
/**
* set new direction to point to
* @param dir new direction
*/
virtual void SetDirection (const cVertex &dir);
/**
* set new cutoff
* @param angle 0..90 (180 means point light)
*/
virtual void SetCutOff (const GLfloat cutoff);
/**
* set new light distribution exponent
* @param exponent 0..128 (0 = uniform light distribution)
*/
virtual void SetExponent (const GLfloat exponent);
/**
* event receiver - we listen for switchon/switchoff events
*
* @return 0 - event accepted, -1 - event not
* accepted
*/
virtual int ReceiveEvent (const cEvent &event);
protected:
/**
* this one performs the actual set up of the light
*
* (called by Activate()); separeted to simplify
* cSpotLight
*/
virtual void ActivateLight ();
/**
* A light is a visible object therefore it needs a drawing function
*
* Not used here - a SpotLight cannot be drawn!
*/
virtual void DrawThisObject ();
/**
* restore old cutoff/exponent (called by cLight::Deactivate())
*/
virtual void DeactivateLight ();
/**
* we want to get events for altering cutoff/exponent
*/
virtual void SubscribeToActiveEvents ();
/**
* unsubscribe from events if we get deselected
*/
virtual void UnsubscribeFromActiveEvents ();
/**
* identify an instance of this class if it's got no name
*/
virtual const char *GetDefaultName () const
{
return "cLight";
}
/** actual direction */
cVertex mDirection;
/** current cutoff */
GLfloat mCutOff;
/** current exponent */
GLfloat mExponent;
/** saved cutoff */
GLfloat mOldCutOff;
/** saved exponent */
GLfloat mOldExponent;
};
#endif // ifndef cSpotLight_hh
|