FGFS-4.1/simgear
3
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Changes to integrate Durk's moon/sun code updates + clean up.

Browse Source
This commit is contained in:
curt
1997-11-25 19:25:27 +00:00
parent 5730a47b00
commit b6f07f3058
5 changed files with 348 additions and 71 deletions
Download Patch File Download Diff File Expand all files Collapse all files
Scenery/sun.c
+148 -6
View File
@@ -22,9 +22,18 @@
* (Log is kept at end of this file)
**************************************************************************/
#include <GL/glut.h>
#include "../Time/fg_time.h"
#include "../Main/views.h"
#include "orbits.h"
#include "sun.h"
GLint sun;
static struct CelestialCoord
sunPos;
float xSun, ySun, zSun;
struct SunPos fgCalcSunPos(struct OrbElements params)
{
@@ -38,24 +47,157 @@ struct SunPos fgCalcSunPos(struct OrbElements params)
EccAnom = fgCalcEccAnom(params.M, params.e);
/* calculate the Suns distance (r) and its true anomaly (v) */
xv = cos(EccAnom) - params.e;
xv = cos(EccAnom) - params.e;
yv = sqrt(1.0 - params.e*params.e) * sin(EccAnom);
v = atan2(yv, xv);
r = sqrt(xv*xv + yv*yv);
/* calculate the the Suns true longitude (lonsun) */
/* calculate the the Sun's true longitude (lonsun) */
lonSun = v + params.w;
/* convert true longitude and distance to ecliptic rectangular geocentric
coordinates (xs, ys) */
coordinates (xs, ys) */
solarPosition.xs = r * cos(lonSun);
solarPosition.ys = r * sin(lonSun);
return solarPosition;
}
struct CelestialCoord fgCalculateSun(struct OrbElements params, struct fgTIME t)
{
struct CelestialCoord
result;
struct SunPos
SolarPosition;
double
xe, ye, ze, ecl, actTime;
/* calculate the angle between ecliptic and equatorial coordinate system */
actTime = fgCalcActTime(t);
ecl = fgDegToRad(23.4393 - 3.563E-7 * actTime); // Angle now in Rads
/* calculate the sun's ecliptic position */
SolarPosition = fgCalcSunPos(params);
/* convert ecliptic coordinates to equatorial rectangular geocentric coordinates */
xe = SolarPosition.xs;
ye = SolarPosition.ys * cos(ecl);
ze = SolarPosition.ys * sin(ecl);
/* and finally... Calulate Right Ascention and Declination */
result.RightAscension = atan2( ye, xe);
result.Declination = atan2(ze, sqrt(xe*xe + ye*ye));
return result;
}
/* Initialize the Sun */
void fgSunInit()
{
// int i;
// sun = glGenLists(1);
// glNewList(sun, GL_COMPILE );
// glBegin( GL_POINTS );
fgSolarSystemUpdate(&(pltOrbElements[0]), cur_time_params);
sunPos = fgCalculateSun(pltOrbElements[0], cur_time_params);
#ifdef DEBUG
printf("Sun found at %f (ra), %f (dec)\n", sunPos.RightAscension, sunPos.Declination);
#endif
/* give the moon a temporary color, for testing purposes */
// glColor3f( 0.0, 1.0, 0.0);
// glVertex3f( 190000.0 * cos(moonPos.RightAscension) * cos(moonPos.Declination),
// 190000.0 * sin(moonPos.RightAscension) * cos(moonPos.Declination),
// 190000.0 * sin(moonPos.Declination) );
//glVertex3f(0.0, 0.0, 0.0);
// glEnd();
// glColor3f(1.0, 1.0, 1.0);
//xMoon = 190000.0 * cos(moonPos.RightAscension) * cos(moonPos.Declination);
//yMoon = 190000.0 * sin(moonPos.RightAscension) * cos(moonPos.Declination);
//zMoon = 190000.0 * sin(moonPos.Declination);
xSun = 60000.0 * cos(sunPos.RightAscension) * cos(sunPos.Declination);
ySun = 60000.0 * sin(sunPos.RightAscension) * cos(sunPos.Declination);
zSun = 60000.0 * sin(sunPos.Declination);
// glPushMatrix();
// glTranslatef(x, y, z);
// glScalef(16622.8, 16622.8, 16622.8);
// glBegin(GL_TRIANGLES);
// for (i = 0; i < 20; i++)
// subdivide(&vdata[tindices[i][0]][0],
// &vdata[tindices[i][1]][0],
// &vdata[tindices[i][2]][0], 3);
// glutSolidSphere(1.0, 25, 25);
// glEnd();
//glPopMatrix();
// glEndList();
}
/* Draw the Sun */
void fgSunRender() {
struct VIEW *v;
struct fgTIME *t;
GLfloat color[4] = { 0.85, 0.65, 0.05, 1.0 };
/* double x_2, x_4, x_8, x_10; */
/* GLfloat ambient; */
/* GLfloat amb[3], diff[3]; */
t = &cur_time_params;
v = &current_view;
/* x_2 = t->sun_angle * t->sun_angle;
x_4 = x_2 * x_2;
x_8 = x_4 * x_4;
x_10 = x_8 * x_2; */
/* ambient = (0.4 * pow(1.1, -x_10 / 30.0));
if ( ambient < 0.3 ) ambient = 0.3;
if ( ambient > 1.0 ) ambient = 1.0;
amb[0] = 0.50 + ((ambient * 6.66) - 1.6);
amb[1] = 0.00 + ((ambient * 6.66) - 1.6);
amb[2] = 0.00 + ((ambient * 6.66) - 1.6);
amb[3] = 0.00;
#ifdef DEBUG
printf("Color of the sun: %f, %f, %f\n"
"Ambient value : %f\n"
"Sun Angle : %f\n" , amb[0], amb[1], amb[2], ambient, t->sun_angle);
#endif
diff[0] = 0.0;
diff[1] = 0.0;
diff[2] = 0.0;
diff[3] = 0.0; */
/* set lighting parameters */
/* glLightfv(GL_LIGHT0, GL_AMBIENT, color );
glLightfv(GL_LIGHT0, GL_DIFFUSE, color );
glMaterialfv(GL_FRONT, GL_AMBIENT, amb);
glMaterialfv(GL_FRONT, GL_DIFFUSE, diff); */
glDisable( GL_LIGHTING );
glPushMatrix();
glTranslatef(xSun, ySun, zSun);
glScalef(1400, 1400, 1400);
glColor3fv( color );
/* glutSolidSphere(1.0, 25, 25); */
glutSolidSphere(1.0, 10, 10);
//glCallList(sun);
glPopMatrix();
glEnable( GL_LIGHTING );
}
/* $Log$
/* Revision 1.1 1997/10/25 03:16:11 curt
/* Initial revision of code contributed by Durk Talsma.
/* Revision 1.2 1997/11/25 19:25:39 curt
/* Changes to integrate Durk's moon/sun code updates + clean up.
/*
* Revision 1.1 1997/10/25 03:16:11 curt
* Initial revision of code contributed by Durk Talsma.
*
*/