Refactor curve, sag, and swing methods in Line

class

graphic.py

@@ -42,7 +42,7 @@ class Line:
         self._points = None
         self._rotation = None
 
-    def curve(self):
+    def curve(self,draw=False)->List:
         if self._points:
             return self._points
         start_p = self._start_p
@@ -53,7 +53,7 @@ class Line:
         line = Vector3D(end_p.x, end_p.y, end_p.z) - Vector3D(
             start_p.x, start_p.y, start_p.z
         )
-        # 计算与X轴的角度
+        # 计算与X轴的角度，画弧垂。先沿Z轴旋转到xz平面的x正半轴上。
         xy_project = copy.deepcopy(line)  # 投影到xy平面上
         xy_project.z = 0
         x_abs_angel = xy_project.angle_to(Vector3D(1, 0, 0))
@@ -72,7 +72,7 @@ class Line:
         ] = list()  # 未旋转之前的伪坐标
         for foo in range(len(span_l)):
             p_points.append((span_l[foo] + start_p.x, start_p.y, z_points[foo]))
-        # 绕Z轴旋转
+        # 绕起点，在Z轴方向旋转
         rotation = transformation.Rotation(
             x_angel,
             [start_p.x, start_p.y, start_p.z],
@@ -83,11 +83,12 @@ class Line:
             p_points,
         )
         self._points = points
-        msp = self._msp
-        msp.add_polyline3d(points)
+        if draw:
+            msp = self._msp
+            msp.add_polyline3d(points)
         return points
 
-    def sag(self):
+    def sag(self,draw=False):
         start_p = self._start_p
         end_p = self._end_p
         span = self._span
@@ -114,12 +115,13 @@ class Line:
         ]  # 旋转前的值
         sag_points = rotation.rotate(p_sag_points)
         sag_value = start_p.z + middle_span * height / span - middle_z
-        msp = self._msp
-        msp.add_polyline3d(sag_points)
-        draw_text(msp, f'sag {sag_value}', sag_points[1])
+        if draw:
+            msp = self._msp
+            msp.add_polyline3d(sag_points)
+            draw_text(msp, f'sag {sag_value}', sag_points[1])
         return sag_points
 
-    def swing(self, angel):
+    def swing(self, angel,draw=False)->List:
         if not self._points:
             self.curve()
         points = self._points
@@ -131,8 +133,9 @@ class Line:
             [end_p.x, end_p.y, end_p.z],
         )
         swing_point = swing_rotation.rotate(points)
-        msp = self._msp
-        msp.add_polyline3d(swing_point)
+        if draw:
+            msp = self._msp
+            msp.add_polyline3d(swing_point)
         return swing_point