1 files changed, 33 insertions, 0 deletions
diff --git a/FSF-2020/calculus-of-several-variables/geometry-of-planes-and-curves/space-curves/file4_cone.py b/FSF-2020/calculus-of-several-variables/geometry-of-planes-and-curves/space-curves/file4_cone.py
new file mode 100644
index 0000000..e6ae1c6
--- /dev/null
+++ b/FSF-2020/calculus-of-several-variables/geometry-of-planes-and-curves/space-curves/file4_cone.py
@@ -0,0 +1,33 @@
+from manimlib.imports import *
+
+class cone(ThreeDScene):
+    def construct(self):
+        axes = ThreeDAxes()
+        eqn = TextMobject(r'$z^{2} = x^{2} + y^{2}$')
+
+        conecurve = ParametricFunction(
+            lambda t: np.array([
+                t*np.cos(TAU*t),
+                t*np.sin(TAU*t),
+                t
+            ]), t_min = -2.6, t_max = 2.6
+        ).scale(0.85)
+
+        conesurface = ParametricSurface(
+            lambda u,v: np.array([
+                3*np.sin(u)*np.cos(TAU*v),
+                3*np.sin(u)*np.sin(TAU*v),
+                2.7*u
+            ]), u_min = -1
+        ).scale(0.85)
+
+        self.play(FadeIn(eqn))
+        self.wait(2)
+        self.play(FadeOut(eqn))
+        self.set_camera_orientation(phi = 75*DEGREES, theta=50*DEGREES)
+        self.play(FadeIn(axes), ShowCreation(conecurve, run_time = 3))
+        self.play(FadeOut(conecurve), FadeIn(conesurface))
+        self.begin_ambient_camera_rotation(rate=0.03)
+        self.wait(2)
+        self.play(FadeOut(axes), FadeOut(conesurface))
+        self.wait(2)