CLS
T_INIT

':::::::::::::::::::::::::::
' BASICS EXAMPLES :

'FIGURE 1
CLS
t_pen = 0
T_HOME
 T_PEN = 1
FOR N = 1 TO 720
 T_FD (10)
 T_RT (N)
NEXT N

PAUSE 1

'POLYGONS
CLS
 T_PEN = 0
 T_HOME
 T_PEN = 1
FOR J = 3 TO 12
COLOR J
FOR N = 1 TO J
 T_FD (50)
 T_RT (360/ J)
NEXT N
NEXT J

PAUSE 1

'SPIRAL
CLS
 T_PEN = 0
 T_HOME
 T_PEN = 1
J = 0.05
FOR N = 1 TO 360 * 10
J = J + 0.001
 T_FD (J)
 T_RT (1)
NEXT N

PAUSE 1

'POLIGON SPIRAL
FOR J = 3 TO 12
CLS
 T_PEN = 0
T_HOME
 T_PEN = 1
FOR N = 10 TO 360* 2 STEP 3
 T_FD (10+N)
 T_RT (360/J)
NEXT N
PAUSE 1
NEXT J
PAUSE 1

'CIRCLES
CLS
 T_PEN = 0
T_HOME
 T_PEN = 1
FOR J = 0 TO 5 STEP 0.1
FOR N = 0.25 TO 360
 T_FD (J)
 T_RT (1)
NEXT N
NEXT J

PAUSE 1
COLOR 3
'SHAPE
CLS
T_HOME
 T_PEN = 0
 T_HOME
 T_PEN = 1
FOR N = 1 TO 20
 T_FD (50)
 T_LT (90)
 T_FD (50)
 T_RT (90)
 T_FD (50)
 T_RT (90)
 T_FD (50)
NEXT N
COLOR 1
'Atom Orbit
CLS
T_HOME
 T_PEN = 0
 T_HOME
 T_PEN = 1
for n = 1 to 11
for i = 0 to 359
t_fd (1)
t_rt ((sin(rad(i/2))))
next i
next n

PAUSE 1
COLOR 0
'X
CLS
T_HOME
 T_PEN = 0
FOR J =  0 TO 360*10 STEP 10
T_HOME
T_RT 150
T_FD 100 + (SQR(J/1000))
T_PEN = 1
FOR N = 0 TO 360
T_FD 2+(J/1000)
T_RT 1
NEXT N
T_PEN = 0
NEXT J

COLOR 0
'Z
CLS
T_PEN = 0
T_HOME
T_PEN = 1
FOR N = 0 TO 360000 
T_GT ((sqr(N) * SIN(RAD(n))),( sqr(N) * COS(RAD(n))))
NEXT N

end

'::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
'GRAPH TURTLE 

'VARIABLES
'T_X : DISTANCE IN PIXELS
'T_Y : DISTANCE IN PIXELS
'T_DISTANCE : DISTANCE IN PIXELS
'T_PEN : 0 = PEN OFF   1 = PEN ON
'T_ANGLE : ANGLE IN DEGREES

SUB T_INIT
'INIT GRAPH TURTLE
T_W = XMAX
T_H = YMAX
T_CENTER_SCREEN_X = INT (T_W / 2)
T_CENTER_SCREEN_Y = INT (T_H / 2)
T_POSITION_X = T_CENTER_SCREEN_X
T_POSITION_Y = T_CENTER_SCREEN_Y
T_HEADING = 0
T_PEN = 1
END

SUB T_GT (T_X,T_Y)
'GO TO NEW POSITION X,Y PIXELS
T_NEW_POSITION_X = T_CENTER_SCREEN_X + T_X 
T_NEW_POSITION_Y = T_CENTER_SCREEN_Y + T_Y
IF T_PEN = 1 THEN LINE T_POSITION_X, T_POSITION_Y, T_NEW_POSITION_X, T_NEW_POSITION_Y
T_POSITION_X = T_NEW_POSITION_X
T_POSITION_Y = T_NEW_POSITION_Y
END

SUB T_HOME
'GO HOME TURTLE
IF T_PEN = 1 THEN LINE T_POSITION_X, T_POSITION_Y, T_CENTER_SCREEN_X,T_CENTER_SCREEN_Y
T_POSITION_X  = INT(T_W/2)
T_POSITION_Y  = INT(T_H/2)
END

SUB T_FD (T_DISTANCE)
'FORWARD X DISTANCE PIXELES
T_NEW_POSITION_X = T_POSITION_X + (T_DISTANCE * SIN (T_HEADING))
T_NEW_POSITION_Y = T_POSITION_Y - (T_DISTANCE * COS (T_HEADING))
IF T_PEN = 1 THEN LINE T_POSITION_X, T_POSITION_Y, T_NEW_POSITION_X,T_NEW_POSITION_Y
T_POSITION_X = T_NEW_POSITION_X
T_POSITION_Y = T_NEW_POSITION_Y 
END

SUB T_BK(T_DISTANCE)
'BACK X DISTANCE PIXELES
T_NEW_POSITION_X = T_POSITION_X - ( T_DISTANCE * SIN (T_HEADING))
T_NEW_POSITION_Y = T_POSITION_Y + ( T_DISTANCE * COS (T_HEADING))
IF T_PEN = 1 THEN LINE T_POSITION_X, T_POSITION_Y, T_NEW_POSITION_X,T_NEW_POSITION_Y
T_POSITION_X = T_NEW_POSITION_X
T_POSITION_Y = T_NEW_POSITION_Y 
END

sub T_RT (T_ANGLE)
'TURN RIGHT, ANGLE DEGREES
T_HEADING = T_HEADING +  RAD (T_ANGLE)
END

sub T_LT (T_ANGLE) 
'TURN LEFT, ANGLE DEGREES
T_HEADING = T_HEADING - RAD (T_ANGLE)     
END

sub T_ORIENT (T_ANGLE)
'SET ORIENTATION TURTLE ANGLE DEGREES
T_HEADING = RAD (T_ANGLE)
END