From f16916e3ec09159da9a921b019a158f9bfb06e3d Mon Sep 17 00:00:00 2001
From: Ben Hambrecht <benhbr@gmail.com>
Date: Tue, 6 Feb 2018 11:13:10 +0100
Subject: [PATCH] Added example 3D scene

---
 example_scenes.py | 81 ++++++++++++++++++++++++++++++++++++++++++-----
 1 file changed, 73 insertions(+), 8 deletions(-)

diff --git a/example_scenes.py b/example_scenes.py
index 6855b3cd..0fdcf4e9 100644
--- a/example_scenes.py
+++ b/example_scenes.py
@@ -6,22 +6,23 @@ from mobject.tex_mobject import TexMobject
 from mobject import Mobject
 from mobject.image_mobject import ImageMobject
 from mobject.vectorized_mobject import *
+from mobject.svg_mobject import *
+from mobject.tex_mobject import *
+
+from scene import Scene
+from camera import Camera
 
 from animation.animation import Animation
 from animation.transform import *
 from animation.simple_animations import *
 from animation.playground import *
+
 from topics.geometry import *
 from topics.characters import *
 from topics.functions import *
 from topics.number_line import *
 from topics.combinatorics import *
-from scene import Scene
-from camera import Camera
-from mobject.svg_mobject import *
-from mobject.tex_mobject import *
-
-from mobject.vectorized_mobject import *
+from topics.three_dimensions import *
 
 # To watch one of these scenes, run the following:
 # python extract_scene.py file_name <SceneName> -p
@@ -35,9 +36,9 @@ from mobject.vectorized_mobject import *
 class SquareToCircle(Scene):
     def construct(self):
         circle = Circle()
-        # circle.flip(RIGHT)
-        # circle.rotate(3*TAU/8)
         square = Square()
+        square.flip(RIGHT)
+        square.rotate(-3*TAU/8)
 
         self.play(ShowCreation(square))
         self.play(Transform(square, circle))
@@ -59,6 +60,70 @@ class WriteStuff(Scene):
 
 
 
+class SpinAroundCube(ThreeDScene):
+    # Take a look at ThreeDSCene in three_dimensions.py.
+    # This has a few methods on it like set_camera_position
+    # and move_camera that will be useful.  The main thing to
+    # know about these is that the camera position is thought
+    # of as having spherical coordinates, phi and theta.
+
+    # In general, the nature of how this 3d camera works
+    # is not always robust, you might discover little
+    # quirks here or there
+    def construct(self):
+        axes = ThreeDAxes()
+        cube = Cube(
+            fill_opacity = 1,
+            stroke_color = LIGHT_GREY,
+            stroke_width = 1,
+        )
+        # The constant OUT is np.array([0, 0, 1])
+        cube.next_to(ORIGIN, UP+RIGHT+OUT)
+        self.add(axes, cube)
+
+        # The camera starts positioned with phi=0, meaning it
+        # is directly above the xy-plane, and theta = -TAU/4, 
+        # which makes the "down" direction of the screen point
+        # in the negative y direction.
+
+        # This animates a camera movement
+        self.move_camera(
+            # Tilted 20 degrees off xy plane (70 degrees off the vertical)
+            phi = (70./360.)*TAU,
+            # Positioned above the third quadrant of
+            # the xy-plane
+            theta = (-110./360.)*TAU, 
+            # pass in animation config just like a .play call
+            run_time = 3
+        )
+        self.wait()
+        # If you want the camera to slowly rotate about
+        # the z-axis
+        self.begin_ambient_camera_rotation()
+        self.wait(4)
+        self.play(FadeOut(cube))
+
+
+
+        text = TextMobject("Your ad here")
+        text.rotate(TAU/4, axis = RIGHT)
+        text.next_to(cube, OUT)
+        self.play(Write(text))
+        # If you want to play animations while moving the camera,
+        # include them in an "added_anims" list to move_camera
+        self.move_camera(
+            theta = -0.2*TAU,
+            added_anims = [
+                text.shift, 3*OUT, 
+                text.set_fill, {"opacity" : 1},
+            ]
+        )
+        self.wait(4)
+
+
+
+
+