light wrapper object

sun.h

@@ -0,0 +1,99 @@
+#pragma once
+
+#include "windows.h"
+#include "opengl/glew.h"
+#include "opengl/wglew.h"
+#include "dumb3d.h"
+
+
+//////////////////////////////////////////////////////////////////////////////////////////
+// cSun -- class responsible for dynamic calculation of position and intensity of the Sun,
+//         given current weather, time and geographic location.
+
+class cSun {
+
+public:
+// types:
+
+// methods:
+    void init();
+    void update();
+	void render( Math3D::vector3 const &Origin );
+    // returns location of the sun in the 3d scene
+    Math3D::vector3 getPosition() { return m_position; }
+	// returns vector pointing at the sun
+	Math3D::vector3 getDirection();
+	// returns current elevation above horizon
+	float getAngle();
+	// returns current intensity of the sun
+	float getIntensity();
+	// sets current geographic location
+	void setLocation( float const Longitude, float const Latitude );
+	// sets ambient temperature in degrees C.
+	void setTemperature( float const Temperature );
+	// sets surface pressure in milibars
+	void setPressure( float const Pressure );
+
+// constructors:
+	cSun();
+
+// deconstructor:
+	~cSun();
+
+// members:
+
+protected:
+// types:
+
+// methods:
+	// calculates sun position on the sky given specified time and location
+	void move();
+	// calculates position adjustment due to refraction
+	void refract();
+	// calculates light intensity at current moment
+	void irradiance();
+	// calculates day of year from given date
+	int yearday( int Day, int const Month, int const Year );
+    // obtains current time for calculations
+    void time( SYSTEMTIME *Time );
+
+// members:
+	GLUquadricObj *sunsphere;	// temporary handler for sun positioning test
+
+	struct celestialbody {	// main planet parameters
+
+		double dayang;		// day angle (daynum*360/year-length) degrees
+		double mnlong;		// mean longitude, degrees
+		double mnanom;		// mean anomaly, degrees
+		double eclong;		// ecliptic longitude, degrees.
+		double ecobli;		// obliquity of ecliptic.
+		double declin;		// declination--zenith angle of solar noon at equator, degrees NORTH.
+		double rascen;		// right ascension, degrees
+		double hrang;		// hour angle--hour of sun from solar noon, degrees WEST
+		double zenetr;		// solar zenith angle, no atmospheric correction (= ETR)
+		double zenref;		// solar zenith angle, deg. from zenith, refracted
+		double coszen;		// cosine of refraction corrected solar zenith angle
+		double elevetr;		// solar elevation, no atmospheric correction (= ETR)
+		double elevref;		// solar elevation angle, deg. from horizon, refracted.
+		double distance;	// distance from earth in AUs
+		double erv;			// earth radius vector (multiplied to solar constant)
+		double etr;			// extraterrestrial (top-of-atmosphere) W/sq m global horizontal solar irradiance
+		double etrn;		// extraterrestrial (top-of-atmosphere) W/sq m direct normal solar irradiance
+    };
+
+	struct observer {		// weather, time and position data in observer's location
+
+		double latitude;	// latitude, degrees north (south negative)
+		double longitude;	// longitude, degrees east (west negative)
+		double utime;		// universal (Greenwich) standard time
+		double timezone;	// time zone, east (west negative). USA:  Mountain = -7, Central = -6, etc.
+		double gmst;		// Greenwich mean sidereal time, hours
+		double lmst;		// local mean sidereal time, degrees
+		double temp;		// ambient dry-bulb temperature, degrees C, used for refraction correction
+		double press;		// surface pressure, millibars, used for refraction correction and ampress
+	};
+
+    celestialbody m_body;
+    observer m_observer;
+    Math3D::vector3 m_position;
+};