Add example for :class:~.ParametricSurface (#1657)

* Add example.

* fix example placement.

* Update manim/mobject/three_dimensions.py

Co-authored-by: Jason Villanueva <[email protected]>

* Update manim/mobject/three_dimensions.py

Co-authored-by: Abhijith Muthyala <[email protected]>

* Update manim/mobject/three_dimensions.py

Co-authored-by: Abhijith Muthyala <[email protected]>

* Update three_dimensions.py

Co-authored-by: Jason Villanueva <[email protected]>
Co-authored-by: Abhijith Muthyala <[email protected]>

Author: 3 people

manim/mobject/three_dimensions.py

@@ -32,6 +32,30 @@ def __init__(self, shade_in_3d=True, **kwargs):
 
 
 class ParametricSurface(VGroup):
+    """Creates a Parametric Surface
+
+    Examples
+    --------
+    .. manim:: ParaSurface
+        :save_last_frame:
+
+        class ParaSurface(ThreeDScene):
+            def func(self, u, v):
+                return np.array([np.cos(u) * np.cos(v), np.cos(u) * np.sin(v), u])
+
+            def construct(self):
+                axes = ThreeDAxes(x_range=[-4,4], x_length=8)
+                surface = ParametricSurface(
+                    lambda u, v: axes.c2p(*self.func(u, v)),
+                    u_min=-PI,
+                    u_max=PI,
+                    v_min=0,
+                    v_max=TAU,
+                )
+                self.set_camera_orientation(theta=70 * DEGREES, phi=75 * DEGREES)
+                self.add(axes, surface)
+    """
+
     def __init__(
         self,
         func,