Initial zoom in on diamond fractal

constants.py

@@ -6,7 +6,8 @@ DEFAULT_WIDTH  = 1920
 
 LOW_QUALITY_FRAME_DURATION = 1./20
 MEDIUM_QUALITY_FRAME_DURATION = 1./30
-PRODUCTION_QUALITY_FRAME_DURATION = 1./60
+# PRODUCTION_QUALITY_FRAME_DURATION = 1./60
+PRODUCTION_QUALITY_FRAME_DURATION = 1./30
 
 #There might be other configuration than pixel_shape later...
 PRODUCTION_QUALITY_CAMERA_CONFIG = {

fractal_dimension.py

@@ -57,70 +57,111 @@ class SierpinskiTest(Scene):
 class ZoomInOnFractal(PiCreatureScene):
     CONFIG = {
         "fractal_order" : 6,
-        "num_zooms" : 4,
-        "fractal_class" : Sierpinski,
+        "num_zooms" : 5,
+        "fractal_class" : DiamondFractal,
         "index_to_replace" : 0,
     }
     def construct(self):
         morty = self.pi_creature
-        fractal = self.get_zoomable_fractal()
 
-        fractal.show()
-        
-        self.play(
-            ShowCreation(
-                fractal, 
-                run_time = 4, 
-                rate_func = rush_from
-            ),
-            morty.change_mode, "hooray",
-        )
-        self.dither()
-        self.play(
-            ApplyMethod(
-                fractal.scale, 2**self.num_zooms, 
-                self.zoom_in_about_point,
-                run_time = 8
-            ),
-            morty.change_mode, "thinking",
-            morty.look_at, fractal.get_corner(self.zoom_in_about_point),
-        )
-        self.play(Blink(morty))
-        self.dither()
-
-    def get_zoomable_fractal(self):
         fractal = self.fractal_class(order = self.fractal_order)
+        fractal.show()
 
-        to_be_tweaked = fractal
-        for x in range(self.num_zooms):
-            new_corner = self.fractal_class(order = self.fractal_order)
-            new_corner.replace(to_be_tweaked[self.index_to_replace])
-            self.tweak_subpart(new_corner)
-            to_be_tweaked.submobjects[self.index_to_replace] = new_corner
-            to_be_tweaked = new_corner
-        self.zoom_in_about_point = to_be_tweaked.get_center()
+        fractal = self.introduce_fractal()
+        self.change_mode("thinking")
+        self.blink()
+        self.zoom_in(fractal)
 
+
+    def introduce_fractal(self):
+        fractal = self.fractal_class(order = 0)
+        self.play(FadeIn(fractal))
+        for order in range(1, self.fractal_order+1):
+            new_fractal = self.fractal_class(order = order)
+            self.play(
+                Transform(fractal, new_fractal, run_time = 2),
+                self.pi_creature.change_mode, "hooray"
+            )
         return fractal
 
-    def tweak_subpart(self, subpart):
-        pass
+    def zoom_in(self, fractal):
+        grower = fractal[self.index_to_replace]
+        grower_target = fractal.copy()
+
+        for x in range(self.num_zooms):
+            self.tweak_fractal_subpart(grower_target)
+            grower_family = grower.family_members_with_points()
+            everything = VGroup(*[
+                submob
+                for submob in fractal.family_members_with_points()
+                if not submob.is_off_screen()
+                if submob not in grower_family
+            ])
+            everything.generate_target()
+            everything.target.shift(
+                grower_target.get_center()-grower.get_center()
+            )
+            everything.target.scale(
+                grower_target.get_height()/grower.get_height()
+            )
+
+            self.play(
+                Transform(grower, grower_target),
+                MoveToTarget(everything),
+                self.pi_creature.change_mode, "thinking",
+                run_time = 2
+            )
+            self.dither()
+            grower_target = grower.copy()            
+            grower = grower[self.index_to_replace]
 
 
-class ZoomInOnDiamondFractal(ZoomInOnFractal):
-    CONFIG = {
-        "fractal_order" : 5,
-        "fractal_class" : DiamondFractal,
-    }
+    def tweak_fractal_subpart(self, subpart):
+        subpart.rotate_in_place(np.pi/4)
+
+class WhatAreFractals(TeacherStudentsScene):
     def construct(self):
-        high_res_fractal = self.fractal_class(order = self.fractal_order)
-        low_res_fractal = self.fractal_class(order = self.fractal_order-1)
-
-        high_res_fractal.scale(3, high_res_fractal.get_top())
-
-        self.add(low_res_fractal)
+        self.student_says(
+            "But what \\emph{is} a fractal",
+            student_index = 2,
+            width = 6
+        )
+        self.change_student_modes("thinking", "pondering", None)
         self.dither()
-        self.play(Transform(low_res_fractal, high_res_fractal))
-        self.dither(3)
+
+        name = TextMobject("Benoit Mandelbrot")
+        name.to_corner(UP+LEFT)
+        # picture = Rectangle(height = 4, width = 3)
+        picture = ImageMobject("Mandelbrot")
+        picture.scale_to_fit_height(4)
+        picture.next_to(name, DOWN)
+        self.play(
+            Write(name, run_time = 2),
+            FadeIn(picture),
+            *[
+                ApplyMethod(pi.look_at, name)
+                for pi in self.get_everyone()
+            ]
+        )
+        self.dither(2)
+        question = TextMobject("Aren't they", "self-similar", "shapes?")
+        question.highlight_by_tex("self-similar", YELLOW)
+        self.student_says(question)
+        self.play(self.get_teacher().change_mode, "happy")
+        self.dither(2)
+
+
+
+
+
+
+
+
+
+
+
+
+
 
 
 

helpers.py

@@ -116,6 +116,8 @@ def color_to_int_rgb(color):
     return (255*color_to_rgb(color)).astype('uint8')
 
 def color_gradient(reference_colors, length_of_output):
+    if length_of_output == 0:
+        return reference_colors[0]
     rgbs = map(color_to_rgb, reference_colors)
     alphas = np.linspace(0, (len(rgbs) - 1), length_of_output)
     floors = alphas.astype('int')

mobject/mobject.py

@@ -270,6 +270,17 @@ class Mobject(object):
                 self.to_edge(vect, **kwargs)
         return self
 
+    def is_off_screen(self):
+        if self.get_left()[0] > SPACE_WIDTH:
+            return True
+        if self.get_right()[0] < -SPACE_WIDTH:
+            return True
+        if self.get_bottom()[1] > SPACE_HEIGHT:
+            return True
+        if self.get_top()[1] < -SPACE_HEIGHT:
+            return True
+        return False
+
     def stretch_in_place(self, factor, dim):
         self.do_in_place(self.stretch, factor, dim)
         return self

topics/fractals.py

@@ -30,7 +30,12 @@ class SelfSimilarFractal(VMobject):
         self.gradient_highlight(*self.colors)
 
     def generate_points(self):
-        self.submobjects = self.get_order_n_self(self.order).submobjects
+        order_n_self = self.get_order_n_self(self.order)
+        if self.order == 0:
+            self.submobjects = [order_n_self]
+        else:
+            self.submobjects = order_n_self.submobjects
+        return self
 
     def get_order_n_self(self, order):
         if order == 0:
@@ -69,7 +74,8 @@ class Sierpinski(SelfSimilarFractal):
 class DiamondFractal(SelfSimilarFractal):
     CONFIG = {
         "num_subparts" : 4,
-        "height" : 6,
+        "height" : 4,
+        "colors" : [GREEN_E, YELLOW],
     }
     def get_seed_shape(self):
         return RegularPolygon(n = 4)