用lisp语言如何实现在CAD中给一个正方形充填？（四点坐标已知）

(defun c:tc()
(setq pt1(getpoint"输入第1点坐标"))
(setq pt2(getpoint"输入第2点坐标"))
(setq pt3(getpoint"输入第3点坐标"))
(setq pt4(getpoint"输入第4点坐标"))
(command "line" pt1 pt2 pt3 pt4 "c")
(setq tc entlast)
(command "solid" tc "")
(princ)
)

(defun c:tc()
(setq pt1(getpoint "输入第1点坐标"))
(setq pt2(getpoint pt1 "输入第2点坐标"))
(setq pt3(getpoint pt2 "输入第3点坐标"))
(setq pt4(getpoint pt3 "输入第4点坐标"))
(command "pline" pt1 pt2 pt3 pt4 "c")
(command "_hatch" "SOLID" (entlast) "")
(princ)
)