DIM SHARED angle AS Double

SUB turn (degrees AS Double)
    angle = angle + degrees*3.14159265/180
END SUB

SUB forward (length AS Double)
    LINE - STEP (cos(angle)*length, sin(angle)*length), 7
END SUB

SUB dragon (length AS Double, split AS Integer, d AS Double)
    IF split=0 THEN
        forward length
    ELSE
    turn d*45
    dragon length/1.4142136, split-1, 1
    turn -d*90
    dragon length/1.4142136, split-1, -1
    turn d*45
    END IF
END SUB

' Main program

SCREEN 12
angle = 0
PSET (150,180), 0
dragon 400, 12, 1
SLEEP