#include

#include

float x $=0$;

float y $=0$;

int ligt $=0$;

float red $=1\mathrm{.}0$f$,$ blue $=0\mathrm{.}0$f$,$ green $=0\mathrm{.}0$f;

void processSpecialKeys$($int key, int x$,$ int y$)$;

void processSpecialKeys$($int key, int x$,$ int y$)\{$

switch $($key$)\{$

case GLUT$\_$KEY$\_$F$1$:

red $=1\mathrm{.}0$;

green $=1\mathrm{.}0$;

blue $=0\mathrm{.}0$; break;

case GLUT$\_$KEY$\_$F$2$:

red $=0\mathrm{.}666$;

green $=\mathrm{.}666$;

blue $=1\mathrm{.}0$; break;

case GLUT$\_$KEY$\_$F$3$:

red $=0\mathrm{.}0$;

green $=0\mathrm{.}555$;

blue $=\mathrm{.}555$; break;

$\}$

$\}$

void Drow$()\{$

glClear$($GL$\_$COLOR$\_$BUFFER$\_$BIT $|$ GL$\_$DEPTH$\_$BUFFER$\_$BIT$)$;

glPushMatrix$()$;

gluLookAt$(0\mathrm{.}0$f$,0\mathrm{.}0$f$,150\mathrm{.}0$f$,0\mathrm{.}0$f$,0\mathrm{.}0$f$,0\mathrm{.}0$f$,0\mathrm{.}0$f$,1\mathrm{.}0$f$,0\mathrm{.}0$f$)$;

glShadeModel$($GL$\_$SMOOTH$)$;

glEnable$($GL$\_$LIGHTING$)$;

glEnable$($GL$\_$LIGHT$1)$;

GLfloat position$[]=\{0,0,1,0\}$;

glLightfv$($GL$\_$LIGHT$1,$ GL$\_$POSITION, position$)$;

glEnable$($GL$\_$COLOR$\_$MATERIAL$)$;

glEnable$($GL$\_$LIGHTING$)$;

glEnable$($GL$\_$LIGHT$0)$;

$//$spaceship

glColor$3$f$($red$,$ green, blue$)$;

glColor$3$f$(0,1,1)$;

glPushMatrix$()$;

glTranslated$($x$,$ y$,0)$;

glRotatef$(50,0,0,1)$;

glScaled$(1,\mathrm{.}9,1)$;

glutSolidSphere$(13,15,15)$;

glPopMatrix$()$;

glPushMatrix$()$;

$//$ the moon

glColor$3$f$(\mathrm{.}888,\mathrm{.}888,\mathrm{.}888)$;

glTranslated$(-50,-50,0)$;

glutSolidSphere$(30,100,5)$;

glPopMatrix$()$;

$//$black circule in the moon

glPushMatrix$()$;

glColor$3$f$(0,1,0)$;

glTranslated$(-40,-40,0)$;

glutSolidSphere$(10,20,5)$;

glPopMatrix$()$;

glPushMatrix$()$;

$//$the earth

glColor$3$f$(0,0,\mathrm{.}777)$;

glTranslated$(-10,40,0)$;

glutSolidSphere$(17,100,100)$;

glPopMatrix$()$;

glPushMatrix$()$;

glTranslated$($x$,$ y$,0)$;

glLineWidth$(5\mathrm{.}0$f$)$;

glBegin$($GL$\_$LINES$)$;

glColor$3$f$(1,1,0)$;

glVertex$3$f$(0,0,0)$; $//$ Center of the circle

glVertex$3$f$(12,12,9)$; $//$ Point on the circle's circumference

glEnd$()$;

glPopMatrix$()$;

glPushMatrix$()$;

glTranslated$($x$,$ y$,0)$;

glLineWidth$(5\mathrm{.}0$f$)$;

glBegin$($GL$\_$LINES$)$;

glColor$3$f$(1,1,0)$;

glVertex$3$f$(-4,-2,0)$; $//$ Center of the circle

glVertex$3$f$(-17,-11,-16)$; $//$ Point on the circle's circumference

glEnd$()$;

glPopMatrix$()$;

glPushMatrix$()$;

glTranslated$($x$,$ y$,0)$;

glLineWidth$(5\mathrm{.}0$f$)$;

glBegin$($GL$\_$LINES$)$;

glColor$3$f$(1,1,0)$;

glVertex$3$f$(-3,-6,-1)$; $//$ Center of the circle

glVertex$3$f$(-8,-19,-17)$; $//$ Point on the circle's circumference

glEnd$()$;

glPopMatrix$()$;

glColor$3$f$(1\mathrm{.}0$f$,1\mathrm{.}0$f$,1\mathrm{.}0$f$)$;

glPointSize$(4\mathrm{.}5$f$)$; $//$ Set the point size for stars

glBegin$($GL$\_$POINTS$)$;

glColor$3$f$(1,1,1)$;

for $($int i $=0$; i $<1000$; $++$i$)\{$

float rx $=($float$)($rand$()\%600-300)$; $//$ Random x coordinate within viewport

float ry $=($float$)($rand$()\%600-300)$; $//$ Random y coordinate within viewport

glVertex$3$f$($rx$,$ ry$,-50\mathrm{.}0$f$)$; $//$ Draw stars randomly in the background

$\}$

glEnd$()$;

$//$circul around the space ship

glPushMatrix$()$;

glColor$3$f$(1,1,0)$;

glTranslated$($x$,$ y$,0)$;

glRotatef$(250,1,0,1)$;

glutSolidTorus$(2\mathrm{.}5,17,15,15)$;

glPopMatrix$()$;

glPopMatrix$()$;

glPopMatrix$()$;

glDisable$($GL$\_$LIGHTING$)$;

glDisable$($GL$\_$COLOR$\_$MATERIAL$)$;

glDisable$($GL$\_$LIGHT$0)$;

$//$moving the space ship

x $+=0\mathrm{.}03$;

if $($x $>50)\{$

x $=-50$;

$\}$

y $+=0\mathrm{.}03$;

if $($y $>50)\{$

y $=-50$;

$\}$

glutSwapBuffers$()$;

glutSpecialFunc$($processSpecialKeys$)$;

$\}$

int main$()\{$

glutInitDisplayMode$($GLUT$\_$DEPTH $|$ GLUT$\_$DOUBLE $|$ GLUT$\_$RGBA$)$;

glutInitWindowPosition$(100,100)$;

glutInitWindowSize$(400,400)$;

glutCreateWindow$("$project$")$;

glEnable$($GL$\_$DEPTH$\_$TEST$)$;

glMatrixMode$($GL$\_$PROJECTION$)$;

glLoadIdentity$()$;

gluPerspective$(45,1,80,-100\mathrm{.}0$f$)$;

glMatrixMode$($GL$\_$MODELVIEW$)$;

glLoadIdentity$()$;

glutDisplayFunc$($Drow$)$;

glClearColor$(0,0,0,0)$;

glutIdleFunc$($Drow$)$;

glutMainLoop$()$;

$\}$

I want to modify the code above by $1-$ Adding gray spots on the moon to make it more realistic. $2-$ Adding a green color to the blue ball to resemble planet Earth.