Dim xpen, ypen, zoom, cx, cy /* ペンの現在位置 */ zoom =50 cx = 320 cy = 200 Sub move(x, y) /* ペンアップで移動 */ xpen = x *zoom ypen = y *zoom End Sub
Sub move_rel(dx, dy) /* 同上 (相対座標) */ xpen += dx *zoom ypen += dy *zoom End Sub
Sub draw(x, y) /* ペンダウンで移動 */ Line(cx+xpen, cy-ypen)-(cx+x*zoom,cy- y*zoom) xpen = x *zoom ypen = y *zoom End Sub
Sub draw_rel(dx, dy) /* 同上 (相対座標) */ Line(cx+xpen, cy-ypen)-(cx+(xpen + dx*zoom), cy-(ypen + dy*zoom)) xpen += dx *zoom ypen += dy *zoom End Sub
Sub dragon(i As Long, dx, dy, sign As Long) If i = 0 Then draw_rel(dx, dy) Else dragon(i-1, (dx-sign*dy)/2, (dy+sign*dx)/2, 1) dragon(i-1, (dx+sign*dy)/2, (dy-sign*dx)/2, -1) End If End Sub
Sub main() Dim order As Long
Input "位数 = ";order move(1, 2) dragon(order, 2, 0, 1) End Sub