This simple short demo shows a how to set night and day on an x model terrain using a sun and light source rotating around the terrain model. NB. Uses EZrotate

                                    ` This code was downloaded from The Game Creators
                                    ` It is reproduced here with full permission
                                    ` http://www.thegamecreators.com
                                    
                                    REM Project: Terrain x
REM Created: 9/7/2005 18:15:12
REM
REM ***** Main Source File *****
REM ****** DAY & NIGHT DEMO ****
REM ** By John Keenleyside *****

global sun=3
global sunangle=0
global seconds
global count
posy#=90
posx#=0

perform checklist for graphics cards
for c=1 to checklist quantity()
name$=checklist string$(c)
next c
set graphics card name$
SET DISPLAY MODE 640,480,32

sync on : sync rate 0 : Autocam off : hide mouse : randomize timer(): backdrop on

make camera 1
set current camera 1
set camera range 1,2,8300
set ambient light 10

load object "media\mesh.x",1
Position Object 1,0,0,0

make object sphere sun,150
position object sun,2000,0,6000
SET POINT LIGHT 0,object position X(sun),object position Y(sun),object position Z(sun)
SET LIGHT RANGE 0,18000

make object sphere 2,200
hide object 2
Position Object 2,-1600,1000,2000

do
text 0,40, "FPS          :"+str$(screen fps())
text 0,80, "Sun Angle    :"+str$(sunangle)
text 0,100, "Player x POS :"+str$(object position x(2))
text 0,120, "Player z POS :"+str$(object position z(2))
gosub Movement
gosub TimerS
gosub sunmove
sync
loop

Movement:
posy#=posy#+(mousemovex()/4)
posx#=posx#+(mousemovey()/4)
posx#=posx#
posy#=posy#
Rotate Object 2,posx#,posy#,0
SET camera TO OBJECT ORIENTATION 1,2
POSITION CAMERA 1,object position x(2),object position y(2),object position Z(2)
if upkey() then Move Object 2,4
if downkey() then Move Object 2,-4
if leftkey() then Move Object Left 2,4
if rightkey() then Move Object Right 2,4
return

TimerS:
seconds=count/100
cycle=Timer()/1000
if cycle=Timer()/1000 then count=count+1
return

sunmove:
if seconds=1 `Activate to slow time
restore sun
for l= 1 to 8
read d
if sunangle=d then color backdrop rgb(d,d,d)
next l
   position light 0,object position X(sun),object position Y(sun),object position Z(sun)
   EZro_SetEuler OBJECT ANGLE X(sun),OBJECT ANGLE Y(sun),OBJECT ANGLE Z(sun)
   EZro_SetPos OBJECT POSITION X(sun),OBJECT POSITION Y(sun),OBJECT POSITION Z(sun)
   EZro_Orbit 1,-500,0,2000,4500,0,2000,1
   sunangle=sunangle+1
   if sunangle=360 then sunangle=0
   EZro_FindEuler
   Rotate Object sun,EZro_GetEulerX(),EZro_GetEulerY(),EZro_GetEulerZ()
   Position Object sun,EZro_GetPosX(),EZro_GetPosY(),EZro_GetPosZ()
   count=0
endif  `Activate to slow time
return
sun:
data 4,170,170,255, 10,200,200,255, 140,170,170,255, 100,160,60,60
data 176,40,40,80, 186,0,0,20, 344,60,150,200, 355,150,150,200