from helpers import * from mobject.tex_mobject import TexMobject from mobject import Mobject from mobject.image_mobject import ImageMobject from mobject.vectorized_mobject import * from animation.animation import Animation from animation.transform import * from animation.simple_animations import * from animation.playground import * from animation.continual_animation import * from topics.geometry import * from topics.characters import * from topics.functions import * from topics.fractals import * from topics.number_line import * from topics.combinatorics import * from topics.numerals import * from topics.three_dimensions import * from topics.objects import * from topics.probability import * from topics.complex_numbers import * from scene import Scene from scene.reconfigurable_scene import ReconfigurableScene from scene.zoomed_scene import * from camera import * from mobject.svg_mobject import * from mobject.tex_mobject import * from topics.graph_scene import * # Useful constants to play around with UL = UP + LEFT UR = UP + RIGHT DL = DOWN + LEFT DR = DOWN + RIGHT standard_rect = np.array([UL, UR, DR, DL]) # Used in EquationSolver2d, and a few other places border_stroke_width = 10 # Used for clockwise circling in some scenes cw_circle = Circle(color = WHITE).stretch(-1, 0) # Used when walker animations are on black backgrounds, in EquationSolver2d and PiWalker WALKER_LIGHT_COLOR = DARK_GREY # TODO/WARNING: There's a lot of refactoring and cleanup to be done in this code, # (and it will be done, but first I'll figure out what I'm doing with all this...) # -SR # This turns counterclockwise revs into their color. Beware, we use CCW angles # in all display code, but generally think in this video's script in terms of # CW angles def rev_to_rgba(alpha): alpha = (0.5 - alpha) % 1 # For convenience, to go CW from red on left instead of CCW from right # 0 is red, 1/6 is yellow, 1/3 is green, 2/3 is blue hue_list = [0, 0.5/6.0, 1/6.0, 1.1/6.0, 2/6.0, 3/6.0, 4/6.0, 5/6.0] num_hues = len(hue_list) start_index = int(np.floor(num_hues * alpha)) % num_hues end_index = (start_index + 1) % num_hues beta = (alpha % (1.0/num_hues)) * num_hues start_hue = hue_list[start_index] end_hue = hue_list[end_index] if end_hue < start_hue: end_hue = end_hue + 1 hue = interpolate(start_hue, end_hue, beta) return color_to_rgba(Color(hue = hue, saturation = 1, luminance = 0.5)) # alpha = alpha % 1 # colors = colorslist # num_colors = len(colors) # beta = (alpha % (1.0/num_colors)) * num_colors # start_index = int(np.floor(num_colors * alpha)) % num_colors # end_index = (start_index + 1) % num_colors # return interpolate(colors[start_index], colors[end_index], beta) def rev_to_color(alpha): return rgba_to_color(rev_to_rgba(alpha)) def point_to_rev((x, y), allow_origin = False): # Warning: np.arctan2 would happily discontinuously returns the value 0 for (0, 0), due to # design choices in the underlying atan2 library call, but for our purposes, this is # illegitimate, and all winding number calculations must be set up to avoid this if not(allow_origin) and (x, y) == (0, 0): print "Error! Angle of (0, 0) computed!" return return fdiv(np.arctan2(y, x), TAU) def point_to_size((x, y)): return np.sqrt(x**2 + y**2) # rescaled_size goes from 0 to 1 as size goes from 0 to infinity # The exact method is arbitrarily chosen to make pleasing color map # brightness levels def point_to_rescaled_size(p): base_size = point_to_size(p) return np.sqrt(fdiv(base_size, base_size + 1)) def point_to_rgba(point): rev = point_to_rev(point, allow_origin = True) rgba = rev_to_rgba(rev) rescaled_size = point_to_rescaled_size(point) return rgba * [rescaled_size, rescaled_size, rescaled_size, 1] # Preserve alpha positive_color = rev_to_color(0) negative_color = rev_to_color(0.5) neutral_color = rev_to_color(0.25) # This, the first animation I made, has the messiest code, full of cruft, but so it goes class EquationSolver1d(GraphScene, ZoomedScene): CONFIG = { "camera_config" : { "use_z_coordinate_for_display_order": True, }, "func" : lambda x : x, "targetX" : 0, "targetY" : 0, "initial_lower_x" : 0, "initial_upper_x" : 10, "num_iterations" : 10, "iteration_at_which_to_start_zoom" : None, "graph_label" : None, "show_target_line" : True, "base_line_y" : 0, # The y coordinate at which to draw our x guesses "show_y_as_deviation" : False, # Displays y-values as deviations from target } def drawGraph(self): self.setup_axes() self.graph = self.get_graph(self.func) self.add(self.graph) if self.graph_label != None: curve_label = self.get_graph_label(self.graph, self.graph_label, x_val = 4, direction = LEFT) curve_label.shift(LEFT) self.add(curve_label) if self.show_target_line: target_line_object = DashedLine( self.coords_to_point(self.x_min, self.targetY), self.coords_to_point(self.x_max, self.targetY), dashed_segment_length = 0.1) self.add(target_line_object) target_label_num = 0 if self.show_y_as_deviation else self.targetY target_line_label = TexMobject("y = " + str(target_label_num)) target_line_label.next_to(target_line_object.get_left(), UP + RIGHT) self.add(target_line_label) self.wait() # Give us time to appreciate the graph if self.show_target_line: self.play(FadeOut(target_line_label)) # Reduce clutter print "For reference, graphOrigin: ", self.coords_to_point(0, 0) print "targetYPoint: ", self.coords_to_point(0, self.targetY) # This is a mess right now (first major animation coded), # but it works; can be refactored later or never def solveEquation(self): # Under special conditions, used in GuaranteedZeroScene, we let the # "lower" guesses actually be too high, or vice versa, and color # everything accordingly def color_by_comparison(val, ref): if val > ref: return positive_color elif val < ref: return negative_color else: return neutral_color lower_color = color_by_comparison(self.func(self.initial_lower_x), self.targetY) upper_color = color_by_comparison(self.func(self.initial_upper_x), self.targetY) if self.show_y_as_deviation: y_bias = -self.targetY else: y_bias = 0 startBrace = TexMobject("|", stroke_width = 10) #TexMobject("[") # Not using [ and ] because they end up crossing over startBrace.set_color(lower_color) endBrace = startBrace.copy().stretch(-1, 0) endBrace.set_color(upper_color) genericBraces = Group(startBrace, endBrace) #genericBraces.scale(1.5) leftBrace = startBrace.copy() rightBrace = endBrace.copy() xBraces = Group(leftBrace, rightBrace) downBrace = startBrace.copy() upBrace = endBrace.copy() yBraces = Group(downBrace, upBrace) yBraces.rotate(TAU/4) lowerX = self.initial_lower_x lowerY = self.func(lowerX) upperX = self.initial_upper_x upperY = self.func(upperX) leftBrace.move_to(self.coords_to_point(lowerX, self.base_line_y)) #, aligned_edge = RIGHT) leftBraceLabel = DecimalNumber(lowerX) leftBraceLabel.next_to(leftBrace, DOWN + LEFT, buff = SMALL_BUFF) leftBraceLabelAnimation = ContinualChangingDecimal(leftBraceLabel, lambda alpha : self.point_to_coords(leftBrace.get_center())[0], tracked_mobject = leftBrace) self.add(leftBraceLabelAnimation) rightBrace.move_to(self.coords_to_point(upperX, self.base_line_y)) #, aligned_edge = LEFT) rightBraceLabel = DecimalNumber(upperX) rightBraceLabel.next_to(rightBrace, DOWN + RIGHT, buff = SMALL_BUFF) rightBraceLabelAnimation = ContinualChangingDecimal(rightBraceLabel, lambda alpha : self.point_to_coords(rightBrace.get_center())[0], tracked_mobject = rightBrace) self.add(rightBraceLabelAnimation) downBrace.move_to(self.coords_to_point(0, lowerY)) #, aligned_edge = UP) downBraceLabel = DecimalNumber(lowerY) downBraceLabel.next_to(downBrace, LEFT + DOWN, buff = SMALL_BUFF) downBraceLabelAnimation = ContinualChangingDecimal(downBraceLabel, lambda alpha : self.point_to_coords(downBrace.get_center())[1] + y_bias, tracked_mobject = downBrace) self.add(downBraceLabelAnimation) upBrace.move_to(self.coords_to_point(0, upperY)) #, aligned_edge = DOWN) upBraceLabel = DecimalNumber(upperY) upBraceLabel.next_to(upBrace, LEFT + UP, buff = SMALL_BUFF) upBraceLabelAnimation = ContinualChangingDecimal(upBraceLabel, lambda alpha : self.point_to_coords(upBrace.get_center())[1] + y_bias, tracked_mobject = upBrace) self.add(upBraceLabelAnimation) lowerDotPoint = self.input_to_graph_point(lowerX, self.graph) lowerDotXPoint = self.coords_to_point(lowerX, self.base_line_y) lowerDotYPoint = self.coords_to_point(0, self.func(lowerX)) lowerDot = Dot(lowerDotPoint + OUT, color = lower_color) upperDotPoint = self.input_to_graph_point(upperX, self.graph) upperDot = Dot(upperDotPoint + OUT, color = upper_color) upperDotXPoint = self.coords_to_point(upperX, self.base_line_y) upperDotYPoint = self.coords_to_point(0, self.func(upperX)) lowerXLine = Line(lowerDotXPoint, lowerDotPoint, color = lower_color) upperXLine = Line(upperDotXPoint, upperDotPoint, color = upper_color) lowerYLine = Line(lowerDotYPoint, lowerDotPoint, color = lower_color) upperYLine = Line(upperDotYPoint, upperDotPoint, color = upper_color) self.add(lowerXLine, upperXLine, lowerYLine, upperYLine) self.add_foreground_mobjects(xBraces, yBraces, lowerDot, upperDot) x_guess_line = Line(lowerDotXPoint, upperDotXPoint, color = WHITE, stroke_width = 10) self.add(x_guess_line) lowerGroup = Group( lowerDot, leftBrace, downBrace, lowerXLine, lowerYLine, x_guess_line ) upperGroup = Group( upperDot, rightBrace, upBrace, upperXLine, upperYLine, x_guess_line ) initialLowerXDot = Dot(lowerDotXPoint + OUT, color = lower_color) initialUpperXDot = Dot(upperDotXPoint + OUT, color = upper_color) initialLowerYDot = Dot(lowerDotYPoint + OUT, color = lower_color) initialUpperYDot = Dot(upperDotYPoint + OUT, color = upper_color) self.add_foreground_mobjects(initialLowerXDot, initialUpperXDot, initialLowerYDot, initialUpperYDot) for i in range(self.num_iterations): if i == self.iteration_at_which_to_start_zoom: self.activate_zooming() self.little_rectangle.move_to( self.coords_to_point(self.targetX, self.targetY)) inverseZoomFactor = 1/float(self.zoom_factor) self.play( lowerDot.scale_in_place, inverseZoomFactor, upperDot.scale_in_place, inverseZoomFactor) def makeUpdater(xAtStart, fixed_guess_x): def updater(group, alpha): dot, xBrace, yBrace, xLine, yLine, guess_line = group newX = interpolate(xAtStart, midX, alpha) newY = self.func(newX) graphPoint = self.input_to_graph_point(newX, self.graph) dot.move_to(graphPoint) xAxisPoint = self.coords_to_point(newX, self.base_line_y) xBrace.move_to(xAxisPoint) yAxisPoint = self.coords_to_point(0, newY) yBrace.move_to(yAxisPoint) xLine.put_start_and_end_on(xAxisPoint, graphPoint) yLine.put_start_and_end_on(yAxisPoint, graphPoint) fixed_guess_point = self.coords_to_point(fixed_guess_x, self.base_line_y) guess_line.put_start_and_end_on(xAxisPoint, fixed_guess_point) return group return updater midX = (lowerX + upperX)/float(2) midY = self.func(midX) # If we run with an interval whose endpoints start off with same sign, # then nothing after this branching can be trusted to do anything reasonable # in terms of picking branches or assigning colors in_negative_branch = midY < self.targetY sign_color = negative_color if in_negative_branch else positive_color midCoords = self.coords_to_point(midX, midY) midColor = neutral_color # Hm... even the z buffer isn't helping keep this above x_guess_line midXBrace = startBrace.copy() # Had start and endBrace been asymmetric, we'd do something different here midXBrace.set_color(midColor) midXBrace.move_to(self.coords_to_point(midX, self.base_line_y) + OUT) # We only actually add this much later midXPoint = Dot(self.coords_to_point(midX, self.base_line_y) + OUT, color = sign_color) x_guess_label_caption = TextMobject("New guess: x = ", fill_color = midColor) x_guess_label_num = DecimalNumber(midX, fill_color = midColor) x_guess_label_num.move_to(0.9 * SPACE_HEIGHT * DOWN) x_guess_label_caption.next_to(x_guess_label_num, LEFT) x_guess_label = Group(x_guess_label_caption, x_guess_label_num) y_guess_label_caption = TextMobject(", y = ", fill_color = midColor) y_guess_label_num = DecimalNumber(midY, fill_color = sign_color) y_guess_label_caption.next_to(x_guess_label_num, RIGHT) y_guess_label_num.next_to(y_guess_label_caption, RIGHT) y_guess_label = Group(y_guess_label_caption, y_guess_label_num) guess_labels = Group(x_guess_label, y_guess_label) self.play( ReplacementTransform(leftBrace.copy(), midXBrace), ReplacementTransform(rightBrace.copy(), midXBrace), FadeIn(x_guess_label)) self.add_foreground_mobject(midXBrace) midXLine = DashedLine( self.coords_to_point(midX, self.base_line_y), midCoords, color = midColor ) self.play(ShowCreation(midXLine)) midDot = Dot(midCoords, color = sign_color) if(self.iteration_at_which_to_start_zoom != None and i >= self.iteration_at_which_to_start_zoom): midDot.scale_in_place(inverseZoomFactor) self.add(midDot) midYLine = DashedLine(midCoords, self.coords_to_point(0, midY), color = sign_color) self.play( ShowCreation(midYLine), FadeIn(y_guess_label), ApplyMethod(midXBrace.set_color, sign_color), ApplyMethod(midXLine.set_color, sign_color), run_time = 0.25 ) midYPoint = Dot(self.coords_to_point(0, midY), color = sign_color) self.add(midXPoint, midYPoint) if in_negative_branch: self.play( UpdateFromAlphaFunc(lowerGroup, makeUpdater(lowerX, fixed_guess_x = upperX ) ), FadeOut(guess_labels), ) lowerX = midX lowerY = midY else: self.play( UpdateFromAlphaFunc(upperGroup, makeUpdater(upperX, fixed_guess_x = lowerX ) ), FadeOut(guess_labels), ) upperX = midX upperY = midY #mid_group = Group(midXLine, midDot, midYLine) Removing groups doesn't flatten as expected? self.remove(midXLine, midDot, midYLine, midXBrace) self.wait() def construct(self): self.drawGraph() self.solveEquation() # Returns the value with the same fractional component as x, closest to m def resit_near(x, m): frac_diff = (x - m) % 1 if frac_diff > 0.5: frac_diff -= 1 return m + frac_diff # TODO?: Perhaps use modulus of (uniform) continuity instead of num_checkpoints, calculating # latter as needed from former? def make_alpha_winder(func, start, end, num_checkpoints): check_points = [None for i in range(num_checkpoints)] check_points[0] = func(start) step_size = fdiv(end - start, num_checkpoints) for i in range(num_checkpoints - 1): check_points[i + 1] = \ resit_near( func(start + (i + 1) * step_size), check_points[i]) def return_func(alpha): index = clamp(0, num_checkpoints - 1, int(alpha * num_checkpoints)) x = interpolate(start, end, alpha) return resit_near(func(x), check_points[index]) return return_func def split_interval((a, b)): mid = (a + b)/2.0 return ((a, mid), (mid, b)) class RectangleData(): def __init__(self, x_interval, y_interval): self.rect = (x_interval, y_interval) def get_top_left(self): return np.array((self.rect[0][0], self.rect[1][1])) def get_top_right(self): return np.array((self.rect[0][1], self.rect[1][1])) def get_bottom_right(self): return np.array((self.rect[0][1], self.rect[1][0])) def get_bottom_left(self): return np.array((self.rect[0][0], self.rect[1][0])) def get_top(self): return (self.get_top_left(), self.get_top_right()) def get_right(self): return (self.get_top_right(), self.get_bottom_right()) def get_bottom(self): return (self.get_bottom_right(), self.get_bottom_left()) def get_left(self): return (self.get_bottom_left(), self.get_top_left()) def splits_on_dim(self, dim): x_interval = self.rect[0] y_interval = self.rect[1] # TODO: Can refactor the following; will do later if dim == 0: return_data = [RectangleData(new_interval, y_interval) for new_interval in split_interval(x_interval)] elif dim == 1: return_data = [RectangleData(x_interval, new_interval) for new_interval in split_interval(y_interval)[::-1]] else: print "RectangleData.splits_on_dim passed illegitimate dimension!" return tuple(return_data) def split_line_on_dim(self, dim): x_interval = self.rect[0] y_interval = self.rect[1] if dim == 0: sides = (self.get_top(), self.get_bottom()) elif dim == 1: sides = (self.get_left(), self.get_right()) else: print "RectangleData.split_line_on_dim passed illegitimate dimension!" return tuple([mid(x, y) for (x, y) in sides]) # The various inconsistent choices of what datatype to use where are a bit of a mess, # but I'm more keen to rush this video out now than to sort this out. def complex_to_pair(c): return np.array((c.real, c.imag)) # def complex_poly_with_roots(*roots): # def poly(c): # return np.prod([c - z for z in roots]) # return poly # def complex_func_by_critical_points(roots, poles = []): # numerator = complex_poly_with_roots(*map(pair_to_complex, roots)) # denominator = complex_poly_with_roots(*map(pair_to_complex, poles)) # def rational_func(c): # return numerator(c)/denominator(c) # return rational_func def plane_func_from_complex_func(f): return lambda (x, y) : complex_to_pair(f(complex(x,y))) def point3d_func_from_plane_func(f): def g((x, y, z)): f_val = f((x, y)) return np.array((f_val[0], f_val[1], 0)) return g def point3d_func_from_complex_func(f): return point3d_func_from_plane_func(plane_func_from_complex_func(f)) # Returns a function from 2-ples to 2-ples # This function is specified by a list of (x, y, z) tuples, # and has winding number z (or total of all specified z) around each (x, y) # # Can also pass in (x, y) tuples, interpreted as (x, y, 1) def plane_func_by_wind_spec(*specs): def embiggen(p): if len(p) == 3: return p elif len(p) == 2: return (p[0], p[1], 1) else: print "Error in plane_func_by_wind_spec embiggen!" specs = map(embiggen, specs) pos_specs = filter(lambda (x, y, z) : z > 0, specs) neg_specs = filter(lambda (x, y, z) : z < 0, specs) neg_specs_made_pos = map (lambda (x, y, z) : (x, y, -z), neg_specs) def poly(c, root_specs): return np.prod([(c - complex(x, y))**z for (x, y, z) in root_specs]) def complex_func(c): return poly(c, pos_specs) * np.conjugate(poly(c, neg_specs_made_pos)) return plane_func_from_complex_func(complex_func) # Used in Initial2dFunc scenes, VectorField scene, and ExamplePlaneFunc example_plane_func_spec = [(-3, -1.3, 2), (0.1, 0.2, 1), (2.8, -2, -1)] example_plane_func = plane_func_by_wind_spec(*example_plane_func_spec) empty_animation = EmptyAnimation() class WalkerAnimation(Animation): CONFIG = { "walk_func" : None, # Must be initialized to use "remover" : True, "rate_func" : None, "coords_to_point" : None } def __init__(self, walk_func, val_func, coords_to_point, show_arrows = True, scale_arrows = False, **kwargs): self.walk_func = walk_func self.val_func = val_func self.coords_to_point = coords_to_point self.compound_walker = VGroup() self.show_arrows = show_arrows self.scale_arrows = scale_arrows if "walker_stroke_color" in kwargs: walker_stroke_color = kwargs["walker_stroke_color"] else: walker_stroke_color = BLACK base_walker = Dot().scale(5 * 0.35).set_stroke(walker_stroke_color, 2) # PiCreature().scale(0.8 * 0.35) self.compound_walker.walker = base_walker if show_arrows: self.compound_walker.arrow = Arrow(ORIGIN, 0.5 * RIGHT, buff = 0) self.compound_walker.arrow.match_style(self.compound_walker.walker) self.compound_walker.digest_mobject_attrs() Animation.__init__(self, self.compound_walker, **kwargs) # Perhaps abstract this out into an "Animation updating from original object" class def update_submobject(self, submobject, starting_submobject, alpha): submobject.points = np.array(starting_submobject.points) def update_mobject(self, alpha): Animation.update_mobject(self, alpha) cur_x, cur_y = cur_coords = self.walk_func(alpha) cur_point = self.coords_to_point(cur_x, cur_y) self.mobject.shift(cur_point - self.mobject.walker.get_center()) val = self.val_func(cur_coords) rev = point_to_rev(val) self.mobject.walker.set_fill(rev_to_color(rev)) if self.show_arrows: self.mobject.arrow.set_fill(rev_to_color(rev)) self.mobject.arrow.rotate( rev * TAU, about_point = self.mobject.arrow.get_start() ) if self.scale_arrows: size = point_to_rescaled_size(val) self.mobject.arrow.scale( size * 0.3, # Hack constant; we barely use this feature right now about_point = self.mobject.arrow.get_start() ) def walker_animation_with_display( walk_func, val_func, coords_to_point, number_update_func = None, show_arrows = True, scale_arrows = False, **kwargs ): walker_anim = WalkerAnimation( walk_func = walk_func, val_func = val_func, coords_to_point = coords_to_point, show_arrows = show_arrows, scale_arrows = scale_arrows, **kwargs) walker = walker_anim.compound_walker.walker if number_update_func != None: display = DecimalNumber(0, num_decimal_points = 1, fill_color = WHITE, include_background_rectangle = True) display.background_rectangle.fill_opacity = 0.5 display.background_rectangle.fill_color = GREY display.background_rectangle.scale(1.2) displaycement = 0.5 * DOWN # How about that pun, eh? display.move_to(walker.get_center() + displaycement) display_anim = ChangingDecimal(display, number_update_func, tracked_mobject = walker_anim.compound_walker.walker, **kwargs) anim_group = AnimationGroup(walker_anim, display_anim, rate_func = None) return anim_group else: return walker_anim def LinearWalker( start_coords, end_coords, coords_to_point, val_func, number_update_func = None, show_arrows = True, scale_arrows = False, **kwargs ): walk_func = lambda alpha : interpolate(start_coords, end_coords, alpha) return walker_animation_with_display( walk_func = walk_func, coords_to_point = coords_to_point, val_func = val_func, number_update_func = number_update_func, show_arrows = show_arrows, scale_arrows = scale_arrows, **kwargs) class ColorMappedByFuncScene(Scene): CONFIG = { "func" : lambda p : p, "num_plane" : NumberPlane(), "show_num_plane" : True, "show_output" : False, "hide_background" : False #Background used for color mapped objects, not as background } def short_path_to_long_path(self, filename_with_ext): return os.path.join( self.output_directory, "images", filename_with_ext ) def setup(self): # The composition of input_to_pos and pos_to_color # is to be equal to func (which turns inputs into colors) # However, depending on whether we are showing input or output (via a MappingCamera), # we color the background using either func or the identity map if self.show_output: self.input_to_pos_func = self.func self.pos_to_color_func = lambda p : p else: self.input_to_pos_func = lambda p : p self.pos_to_color_func = self.func jitter_val = 0.1 line_coords = np.linspace(-10, 10) + jitter_val func_hash_points = it.product(line_coords, line_coords) def mini_hasher(p): rgba = point_to_rgba(self.pos_to_color_func(p)) if rgba[3] != 1.0: print "Warning! point_to_rgba assigns fractional alpha", rgba[3] return tuple(rgba) to_hash = tuple(mini_hasher(p) for p in func_hash_points) func_hash = hash(to_hash) # We hash just based on output image # Thus, multiple scenes with same output image can re-use it # without recomputation full_hash = hash((func_hash, self.camera.pixel_shape)) self.background_image_file = self.short_path_to_long_path( "color_mapped_bg_hash_" + str(full_hash) + ".png" ) self.in_background_pass = not os.path.exists(self.background_image_file) print "Background file: " + self.background_image_file if self.in_background_pass: print "The background file does not exist yet; this will be a background creation + video pass" else: print "The background file already exists; this will only be a video pass" def construct(self): if self.in_background_pass: self.camera.set_background_from_func( lambda (x, y): point_to_rgba( self.pos_to_color_func( # Should be self.num_plane.point_to_coords_cheap(np.array([x, y, 0])), # but for cheapness, we'll go with just (x, y), having never altered # any num_plane's from default settings so far (x, y) ) ) ) self.save_image(self.background_image_file, mode = "RGBA") if self.hide_background: # Clearing background self.camera.background_image = None else: # Even if we just computed the background, we switch to the file now self.camera.background_image = self.background_image_file self.camera.init_background() if self.show_num_plane: self.num_plane.fade() self.add(self.num_plane) class PureColorMap(ColorMappedByFuncScene): CONFIG = { "show_num_plane" : False } def construct(self): ColorMappedByFuncScene.construct(self) self.wait() # This sets self.background_image_file, but does not display it as the background class ColorMappedObjectsScene(ColorMappedByFuncScene): CONFIG = { "show_num_plane" : False, "hide_background" : True, } class PiWalker(ColorMappedByFuncScene): CONFIG = { "walk_coords" : [], "step_run_time" : 1, "scale_arrows" : False, "display_size" : False, "display_odometer" : False, "color_foreground_not_background" : False, } def construct(self): ColorMappedByFuncScene.construct(self) if self.color_foreground_not_background or self.display_odometer: # Clear background self.camera.background_image = None self.camera.init_background() num_plane = self.num_plane walk_coords = self.walk_coords points = [num_plane.coords_to_point(x, y) for x, y in walk_coords] polygon = Polygon(*points, color = WHITE) if self.color_foreground_not_background: polygon.stroke_width = border_stroke_width polygon.color_using_background_image(self.background_image_file) total_run_time = len(points) * self.step_run_time polygon_anim = ShowCreation(polygon, run_time = total_run_time, rate_func = None) walker_anim = EmptyAnimation for i in range(len(walk_coords)): start_coords = walk_coords[i] end_coords = walk_coords[(i + 1) % len(walk_coords)] # We need to do this roundabout default argument thing to get the closure we want, # so the next iteration changing start_coords, end_coords doesn't change this closure val_alpha_func = lambda a, start_coords = start_coords, end_coords = end_coords : self.func(interpolate(start_coords, end_coords, a)) if self.display_size: # We need to do this roundabout default argument thing to get the closure we want, # so the next iteration changing val_alpha_func doesn't change this closure number_update_func = lambda a, val_alpha_func = val_alpha_func : point_to_rescaled_size(val_alpha_func(a)) # We only use this for diagnostics else: number_update_func = None new_anim = LinearWalker( start_coords = start_coords, end_coords = end_coords, coords_to_point = num_plane.coords_to_point, val_func = self.func, remover = (i < len(walk_coords) - 1), show_arrows = not self.show_output, scale_arrows = self.scale_arrows, number_update_func = number_update_func, run_time = self.step_run_time, walker_stroke_color = WALKER_LIGHT_COLOR if self.color_foreground_not_background else BLACK ) if self.display_odometer: # Discard above animation and show an odometer instead # We need to do this roundabout default argument thing to get the closure we want, # so the next iteration changing val_alpha_func doesn't change this closure rev_func = lambda a, val_alpha_func = val_alpha_func : point_to_rev(val_alpha_func(a)) base_arrow = Arrow(ORIGIN, RIGHT, buff = 0) new_anim = FuncRotater(base_arrow, rev_func = rev_func, run_time = self.step_run_time, rate_func = None, remover = i < len(walk_coords) - 1, ) walker_anim = Succession(walker_anim, new_anim) # TODO: Allow smooth paths instead of breaking them up into lines, and # use point_from_proportion to get points along the way if self.display_odometer: self.play(walker_anim) else: self.play(polygon_anim, walker_anim) self.wait() class PiWalkerRect(PiWalker): CONFIG = { "start_x" : -1, "start_y" : 1, "walk_width" : 2, "walk_height" : 2, "func" : plane_func_from_complex_func(lambda c: c**2) } def setup(self): TL = np.array((self.start_x, self.start_y)) TR = TL + (self.walk_width, 0) BR = TR + (0, -self.walk_height) BL = BR + (-self.walk_width, 0) self.walk_coords = [TL, TR, BR, BL] PiWalker.setup(self) class PiWalkerCircle(PiWalker): CONFIG = { "radius" : 1, "num_steps" : 100, "step_run_time" : 0.01 } def setup(self): r = self.radius N = self.num_steps self.walk_coords = [r * np.array((np.cos(i * TAU/N), np.sin(i * TAU/N))) for i in range(N)] PiWalker.setup(self) class EquationSolver2d(ColorMappedObjectsScene): CONFIG = { "camera_config" : {"use_z_coordinate_for_display_order": True}, "initial_lower_x" : -5, "initial_upper_x" : 5, "initial_lower_y" : -3, "initial_upper_y" : 3, "num_iterations" : 1, "num_checkpoints" : 10, "display_in_parallel" : True, "use_fancy_lines" : True, # TODO: Consider adding a "find_all_roots" flag, which could be turned off # to only explore one of the two candidate subrectangles when both are viable # Walker settings "show_arrows" : True, "scale_arrows" : False, # Special case settings # These are used to hack UhOhScene, where we display different colors than # are actually, secretly, guiding the evolution of the EquationSolver2d # # replacement_background_image_file has to be manually configured "show_winding_numbers" : True, # Used for UhOhScene; "manual_wind_override" : None } def construct(self): ColorMappedObjectsScene.construct(self) num_plane = self.num_plane clockwise_val_func = lambda p : -point_to_rev(self.func(p)) base_line = Line(UP, RIGHT, stroke_width = border_stroke_width, color = WHITE) if self.use_fancy_lines: base_line.color_using_background_image(self.background_image_file) def match_style_with_bg(obj1, obj2): obj1.match_style(obj2) bg = obj2.get_background_image_file() if bg != None: obj1.color_using_background_image(bg) run_time_base = 1 run_time_with_lingering = run_time_base + 0.2 base_rate = lambda t : t linger_rate = squish_rate_func(lambda t : t, 0, fdiv(run_time_base, run_time_with_lingering)) # Helper functions for manual_wind_override def head(m): if m == None: return None return m[0] def child(m, i): if m == None or m == 0: return None return m[i + 1] def Animate2dSolver(cur_depth, rect, dim_to_split, sides_to_draw = [0, 1, 2, 3], manual_wind_override = None): print "Solver at depth: " + str(cur_depth) if cur_depth >= self.num_iterations: return empty_animation def draw_line_return_wind(start, end, start_wind, should_linger = False, draw_line = True): alpha_winder = make_alpha_winder(clockwise_val_func, start, end, self.num_checkpoints) a0 = alpha_winder(0) rebased_winder = lambda alpha: alpha_winder(alpha) - a0 + start_wind colored_line = Line(num_plane.coords_to_point(*start) + IN, num_plane.coords_to_point(*end) + IN) match_style_with_bg(colored_line, base_line) walker_anim = LinearWalker( start_coords = start, end_coords = end, coords_to_point = num_plane.coords_to_point, val_func = self.func, # Note: This is the image func, and not logic_func number_update_func = rebased_winder if self.show_winding_numbers else None, remover = True, walker_stroke_color = WALKER_LIGHT_COLOR, show_arrows = self.show_arrows, scale_arrows = self.scale_arrows, ) if should_linger: # Do we need an "and not self.display_in_parallel" here? run_time = run_time_with_lingering rate_func = linger_rate else: run_time = run_time_base rate_func = base_rate opt_line_anim = ShowCreation(colored_line) if draw_line else empty_animation line_draw_anim = AnimationGroup( opt_line_anim, walker_anim, run_time = run_time, rate_func = rate_func) return (line_draw_anim, rebased_winder(1)) wind_so_far = 0 anim = empty_animation sides = [ rect.get_top(), rect.get_right(), rect.get_bottom(), rect.get_left() ] for (i, (start, end)) in enumerate(sides): (next_anim, wind_so_far) = draw_line_return_wind(start, end, wind_so_far, should_linger = i == len(sides) - 1, draw_line = i in sides_to_draw) anim = Succession(anim, next_anim) total_wind = head(manual_wind_override) or round(wind_so_far) if total_wind == 0: coords = [ rect.get_top_left(), rect.get_top_right(), rect.get_bottom_right(), rect.get_bottom_left() ] points = np.array([num_plane.coords_to_point(x, y) for (x, y) in coords]) + 3 * IN # TODO: Maybe use diagonal lines or something to fill in rectangles indicating # their "Nothing here" status? # Or draw a large X or something fill_rect = polygonObject = Polygon(*points, fill_opacity = 0.8, color = DARK_GREY) return Succession(anim, FadeIn(fill_rect)) else: (sub_rect1, sub_rect2) = rect.splits_on_dim(dim_to_split) if dim_to_split == 0: sub_rect_and_sides = [(sub_rect1, 1), (sub_rect2, 3)] else: sub_rect_and_sides = [(sub_rect1, 2), (sub_rect2, 0)] sub_anims = [ Animate2dSolver( cur_depth = cur_depth + 1, rect = sub_rect, dim_to_split = 1 - dim_to_split, sides_to_draw = [side_to_draw], manual_wind_override = child(manual_wind_override, index) ) for (index, (sub_rect, side_to_draw)) in enumerate(sub_rect_and_sides) ] mid_line_coords = rect.split_line_on_dim(dim_to_split) mid_line_points = [num_plane.coords_to_point(x, y) + 2 * IN for (x, y) in mid_line_coords] mid_line = DashedLine(*mid_line_points) if self.display_in_parallel: recursive_anim = AnimationGroup(*sub_anims) else: recursive_anim = Succession(*sub_anims) return Succession(anim, ShowCreation(mid_line), recursive_anim ) lower_x = self.initial_lower_x upper_x = self.initial_upper_x lower_y = self.initial_lower_y upper_y = self.initial_upper_y x_interval = (lower_x, upper_x) y_interval = (lower_y, upper_y) rect = RectangleData(x_interval, y_interval) print "Starting to compute anim" anim = Animate2dSolver( cur_depth = 0, rect = rect, dim_to_split = 0, sides_to_draw = [], manual_wind_override = self.manual_wind_override ) print "Done computing anim" # Keep timing details here in sync with details above rect_points = [ rect.get_top_left(), rect.get_top_right(), rect.get_bottom_right(), rect.get_bottom_left(), ] border = Polygon(*map(lambda x : num_plane.coords_to_point(*x) + IN, rect_points)) match_style_with_bg(border, base_line) rect_time_without_linger = 4 * run_time_base rect_time_with_linger = 3 * run_time_base + run_time_with_lingering def rect_rate(alpha): time_in = alpha * rect_time_with_linger if time_in < 3 * run_time_base: return fdiv(time_in, 4 * run_time_base) else: time_in_last_leg = time_in - 3 * run_time_base alpha_in_last_leg = fdiv(time_in_last_leg, run_time_with_lingering) return interpolate(0.75, 1, linger_rate(alpha_in_last_leg)) border_anim = ShowCreation( border, run_time = rect_time_with_linger, rate_func = rect_rate ) self.play(anim, border_anim) self.wait() # TODO: Perhaps have option for bullets (pulses) to fade out and in at ends of line, instead of # jarringly popping out and in? # # TODO: Perhaps have bullets change color corresponding to a function of their coordinates? # This could involve some merging of functoinality with PiWalker class LinePulser(ContinualAnimation): def __init__(self, line, bullet_template, num_bullets, pulse_time, output_func = None, **kwargs): self.line = line self.num_bullets = num_bullets self.pulse_time = pulse_time self.bullets = [bullet_template.copy() for i in range(num_bullets)] self.output_func = output_func ContinualAnimation.__init__(self, VGroup(line, VGroup(*self.bullets)), **kwargs) def update_mobject(self, dt): alpha = self.external_time % self.pulse_time start = self.line.get_start() end = self.line.get_end() for i in range(self.num_bullets): position = interpolate(start, end, fdiv((i + alpha),(self.num_bullets))) self.bullets[i].move_to(position) if self.output_func: position_2d = (position[0], position[1]) rev = point_to_rev(self.output_func(position_2d)) color = rev_to_color(rev) self.bullets[i].set_color(color) class ArrowCircleTest(Scene): def construct(self): circle_radius = 3 circle = Circle(radius = circle_radius, color = WHITE) self.add(circle) base_arrow = Arrow(circle_radius * 0.7 * RIGHT, circle_radius * 1.3 * RIGHT) def rev_rotate(x, revs): x.rotate(revs * TAU, about_point = ORIGIN) x.set_color(rev_to_color(revs)) return x num_arrows = 8 * 3 # 0.5 - fdiv below so as to get a clockwise rotation from left arrows = [rev_rotate(base_arrow.copy(), 0.5 - (fdiv(i, num_arrows))) for i in range(num_arrows)] arrows_vgroup = VGroup(*arrows) self.play(ShowCreation(arrows_vgroup), run_time = 2.5, rate_func = None) self.wait() class FuncRotater(Animation): CONFIG = { "rev_func" : lambda x : x, # Func from alpha to CCW revolutions, } # Perhaps abstract this out into an "Animation updating from original object" class def update_submobject(self, submobject, starting_submobject, alpha): submobject.points = np.array(starting_submobject.points) def update_mobject(self, alpha): Animation.update_mobject(self, alpha) angle_revs = self.rev_func(alpha) self.mobject.rotate( angle_revs * TAU, about_point = ORIGIN ) self.mobject.set_color(rev_to_color(angle_revs)) class TestRotater(Scene): def construct(self): test_line = Line(ORIGIN, RIGHT) self.play(FuncRotater( test_line, rev_func = lambda x : x % 0.25, run_time = 10)) # TODO: Be careful about clockwise vs. counterclockwise convention throughout! # Make sure this is correct everywhere in resulting video. class OdometerScene(ColorMappedObjectsScene): CONFIG = { # "func" : lambda p : 100 * p # Full coloring, essentially "rotate_func" : lambda x : np.sin(x * TAU), # This is given in terms of CW revs "run_time" : 5, "dashed_line_angle" : None, "biased_display_start" : None } def construct(self): ColorMappedObjectsScene.construct(self) radius = 1.3 circle = Circle(center = ORIGIN, radius = radius) circle.color_using_background_image(self.background_image_file) self.add(circle) if self.dashed_line_angle: dashed_line = DashedLine(ORIGIN, radius * RIGHT) # Clockwise rotation dashed_line.rotate(-self.dashed_line_angle * TAU, about_point = ORIGIN) self.add(dashed_line) num_display = DecimalNumber(0, include_background_rectangle = False) num_display.move_to(2 * DOWN) caption = TextMobject("turns clockwise") caption.next_to(num_display, DOWN) self.add(caption) display_val_bias = 0 if self.biased_display_start != None: display_val_bias = self.biased_display_start - self.rotate_func(0) display_func = lambda alpha : self.rotate_func(alpha) + display_val_bias base_arrow = Arrow(ORIGIN, RIGHT, buff = 0) self.play( FuncRotater(base_arrow, rev_func = lambda x : -self.rotate_func(x)), ChangingDecimal(num_display, display_func), run_time = self.run_time, rate_func = None) ############# # Above are mostly general tools; here, we list, in order, finished or near-finished scenes class FirstSqrtScene(EquationSolver1d): CONFIG = { "x_min" : 0, "x_max" : 2.5, "y_min" : 0, "y_max" : 2.5**2, "graph_origin" : 2.5*DOWN + 5.5*LEFT, "x_axis_width" : 12, "zoom_factor" : 3, "zoomed_canvas_center" : 2.25 * UP + 1.75 * LEFT, "func" : lambda x : x**2, "targetX" : np.sqrt(2), "targetY" : 2, "initial_lower_x" : 1, "initial_upper_x" : 2, "num_iterations" : 5, "iteration_at_which_to_start_zoom" : 3, "graph_label" : "y = x^2", "show_target_line" : True, } class TestFirstSqrtScene(FirstSqrtScene): CONFIG = { "num_iterations" : 1, } FirstSqrtSceneConfig = FirstSqrtScene.CONFIG shiftVal = FirstSqrtSceneConfig["targetY"] class SecondSqrtScene(FirstSqrtScene): CONFIG = { "graph_label" : FirstSqrtSceneConfig["graph_label"] + " - " + str(shiftVal), "show_y_as_deviation" : True, } class TestSecondSqrtScene(SecondSqrtScene): CONFIG = { "num_iterations" : 1 } class GuaranteedZeroScene(SecondSqrtScene): CONFIG = { # Manual config values, not automatically synced to anything above "initial_lower_x" : 1.75, "initial_upper_x" : 2 } class TestGuaranteedZeroScene(GuaranteedZeroScene): CONFIG = { "num_iterations" : 1 } # TODO: Pi creatures intrigued class RewriteEquation(Scene): def construct(self): # Can maybe use get_center() to perfectly center Groups before and after transform f_old = TexMobject("f(x)") f_new = f_old.copy() equals_old = TexMobject("=") equals_old_2 = equals_old.copy() equals_new = equals_old.copy() g_old = TexMobject("g(x)") g_new = g_old.copy() minus_new = TexMobject("-") zero_new = TexMobject("0") f_old.next_to(equals_old, LEFT) g_old.next_to(equals_old, RIGHT) minus_new.next_to(g_new, LEFT) f_new.next_to(minus_new, LEFT) equals_new.next_to(g_new, RIGHT) zero_new.next_to(equals_new, RIGHT) # where_old = TextMobject("Where does ") # where_old.next_to(f_old, LEFT) # where_new = where_old.copy() # where_new.next_to(f_new, LEFT) # qmark_old = TextMobject("?") # qmark_old.next_to(g_old, RIGHT) # qmark_new = qmark_old.copy() # qmark_new.next_to(zero_new, RIGHT) self.add(f_old, equals_old, equals_old_2, g_old) #, where_old, qmark_old) self.wait() self.play( ReplacementTransform(f_old, f_new), ReplacementTransform(equals_old, equals_new), ReplacementTransform(g_old, g_new), ReplacementTransform(equals_old_2, minus_new), ShowCreation(zero_new), # ReplacementTransform(where_old, where_new), # ReplacementTransform(qmark_old, qmark_new), ) self.wait() class SignsExplanation(Scene): def construct(self): num_line = NumberLine(stroke_width = 1) largest_num = 10 num_line.add_numbers(*range(-largest_num, largest_num + 1)) self.add(num_line) self.wait() pos_num = 3 neg_num = -pos_num pos_arrow = Arrow( num_line.number_to_point(0), num_line.number_to_point(pos_num), buff = 0, color = positive_color) neg_arrow = Arrow( num_line.number_to_point(0), num_line.number_to_point(neg_num), buff = 0, color = negative_color) plus_sign = TexMobject("+", fill_color = positive_color) minus_sign = TexMobject("-", fill_color = negative_color) plus_sign.next_to(pos_arrow, UP) minus_sign.next_to(neg_arrow, UP) #num_line.add_numbers(pos_num) self.play(ShowCreation(pos_arrow), FadeIn(plus_sign)) #num_line.add_numbers(neg_num) self.play(ShowCreation(neg_arrow), FadeIn(minus_sign)) class VectorField(Scene): CONFIG = { "func" : example_plane_func, "granularity" : 10, "arrow_scale_factor" : 0.1, "normalized_arrow_scale_factor" : 5 } def construct(self): num_plane = NumberPlane() self.add(num_plane) x_min, y_min = num_plane.point_to_coords(SPACE_WIDTH * LEFT + SPACE_HEIGHT * UP) x_max, y_max = num_plane.point_to_coords(SPACE_WIDTH * RIGHT + SPACE_HEIGHT * DOWN) x_points = np.linspace(x_min, x_max, self.granularity) y_points = np.linspace(y_min, y_max, self.granularity) points = it.product(x_points, y_points) sized_arrows = Group() unsized_arrows = Group() for (x, y) in points: output = self.func((x, y)) output_size = np.sqrt(sum(output**2)) normalized_output = output * fdiv(self.normalized_arrow_scale_factor, output_size) # Assume output has nonzero size here arrow = Vector(output * self.arrow_scale_factor) normalized_arrow = Vector(normalized_output * self.arrow_scale_factor) arrow.move_to(num_plane.coords_to_point(x, y)) normalized_arrow.move_to(arrow) sized_arrows.add(arrow) unsized_arrows.add(normalized_arrow) self.add(sized_arrows) self.wait() self.play(ReplacementTransform(sized_arrows, unsized_arrows)) self.wait() class HasItsLimitations(Scene): CONFIG = { "camera_config" : {"use_z_coordinate_for_display_order": True}, } def construct(self): num_line = NumberLine() num_line.add_numbers() self.add(num_line) self.wait() # We arrange to go from 2 to 4, a la the squaring in FirstSqrtScene base_point = num_line.number_to_point(2) + OUT dot_color = ORANGE DOT_Z = OUT # Note: This z-buffer value is needed for our static scenes, but is # not sufficient for everything, in that we still need to use # the foreground_mobjects trick during animations. # At some point, we should figure out how to have animations # play well with z coordinates. input_dot = Dot(base_point + DOT_Z, color = dot_color) input_label = TexMobject("Input", fill_color = dot_color) input_label.next_to(input_dot, UP + LEFT) input_label.add_background_rectangle() self.add_foreground_mobject(input_dot) self.add(input_label) curved_arrow = Arc(0, color = MAROON_E) curved_arrow.set_bound_angles(np.pi, 0) curved_arrow.generate_points() curved_arrow.add_tip() curved_arrow.move_arc_center_to(base_point + RIGHT) # Could do something smoother, with arrowhead moving along partial arc? self.play(ShowCreation(curved_arrow)) output_dot = Dot(base_point + 2 * RIGHT + DOT_Z, color = dot_color) output_label = TexMobject("Output", fill_color = dot_color) output_label.next_to(output_dot, UP + RIGHT) output_label.add_background_rectangle() self.add_foreground_mobject(output_dot) self.add(output_label) self.wait() num_plane = NumberPlane() num_plane.add_coordinates() new_base_point = base_point + 2 * UP new_input_dot = input_dot.copy().move_to(new_base_point) new_input_label = input_label.copy().next_to(new_input_dot, UP + LEFT) new_curved_arrow = Arc(0).match_style(curved_arrow) new_curved_arrow.set_bound_angles(np.pi * 3/4, 0) new_curved_arrow.generate_points() new_curved_arrow.add_tip() input_diff = input_dot.get_center() - curved_arrow.points[0] output_diff = output_dot.get_center() - curved_arrow.points[-1] new_curved_arrow.shift((new_input_dot.get_center() - new_curved_arrow.points[0]) - input_diff) new_output_dot = output_dot.copy().move_to(new_curved_arrow.points[-1] + output_diff) new_output_label = output_label.copy().next_to(new_output_dot, UP + RIGHT) dot_objects = Group(input_dot, input_label, output_dot, output_label, curved_arrow) new_dot_objects = Group(new_input_dot, new_input_label, new_output_dot, new_output_label, new_curved_arrow) self.play( FadeOut(num_line), FadeIn(num_plane), ReplacementTransform(dot_objects, new_dot_objects), ) self.wait() self.add_foreground_mobject(new_dot_objects) complex_plane = ComplexPlane() complex_plane.add_coordinates() # This looks a little wonky and we may wish to do a crossfade in Premiere instead self.play(FadeOut(num_plane), FadeIn(complex_plane)) self.wait() class ComplexPlaneIs2d(Scene): def construct(self): com_plane = ComplexPlane() self.add(com_plane) # TODO: Add labels to axes, specific complex points self.wait() class NumberLineScene(Scene): def construct(self): num_line = NumberLine() self.add(num_line) # TODO: Add labels, arrows, specific points self.wait() border_color = PURPLE_E inner_color = RED stroke_width = 10 left_point = num_line.number_to_point(-1) right_point = num_line.number_to_point(1) # TODO: Make this line a thin rectangle interval_1d = Line(left_point, right_point, stroke_color = inner_color, stroke_width = stroke_width) rect_1d = Rectangle(stroke_width = 0, fill_opacity = 1, fill_color = inner_color) rect_1d.replace(interval_1d) rect_1d.stretch_to_fit_height(SMALL_BUFF) left_dot = Dot(left_point, stroke_width = stroke_width, color = border_color) right_dot = Dot(right_point, stroke_width = stroke_width, color = border_color) endpoints_1d = VGroup(left_dot, right_dot) full_1d = VGroup(rect_1d, endpoints_1d) self.play(ShowCreation(full_1d)) self.wait() # TODO: Can polish the morphing above; have dots become left and right sides, and # only then fill in the top and bottom num_plane = NumberPlane() random_points = [UP + LEFT, UP + RIGHT, DOWN + RIGHT, DOWN + LEFT] border_2d = Polygon( *random_points, stroke_color = border_color, stroke_width = stroke_width) filling_2d = Polygon( *random_points, fill_color = inner_color, fill_opacity = 0.8, stroke_width = stroke_width) full_2d = VGroup(filling_2d, border_2d) self.play( FadeOut(num_line), FadeIn(num_plane), ReplacementTransform(full_1d, full_2d)) self.wait() class Initial2dFuncSceneBase(Scene): CONFIG = { "func" : point3d_func_from_complex_func(lambda c : c**2 - c**3/5 + 1) # We don't use example_plane_func because, unfortunately, the sort of examples # which are good for demonstrating our color mapping haven't turned out to be # good for visualizing in this manner; the gridlines run over themselves multiple # times in too confusing a fashion } def show_planes(self): print "Error! Unimplemented (pure virtual) show_planes" def shared_construct(self): points = [LEFT + DOWN, RIGHT + DOWN, LEFT + UP, RIGHT + UP] for i in range(len(points) - 1): line = Line(points[i], points[i + 1], color = RED) self.obj_draw(line) def wiggle_around(point): radius = 0.2 small_circle = cw_circle.copy() small_circle.scale(radius) small_circle.move_to(point + radius * RIGHT) small_circle.set_color(RED) self.obj_draw(small_circle) wiggle_around(points[-1]) def obj_draw(self, input_object): self.play(ShowCreation(input_object)) def construct(self): self.show_planes() self.shared_construct() # Alternative to the below, using MappingCameras, but no morphing animation class Initial2dFuncSceneWithoutMorphing(Initial2dFuncSceneBase): def setup(self): left_camera = Camera(**self.camera_config) right_camera = MappingCamera( mapping_func = self.func, **self.camera_config) split_screen_camera = SplitScreenCamera(left_camera, right_camera, **self.camera_config) self.camera = split_screen_camera def show_planes(self): self.num_plane = NumberPlane() self.num_plane.prepare_for_nonlinear_transform() #num_plane.fade() self.add(self.num_plane) # Alternative to the above, manually implementing split screen with a morphing animation class Initial2dFuncSceneMorphing(Initial2dFuncSceneBase): CONFIG = { "num_needed_anchor_points" : 10, } def setup(self): split_line = DashedLine(SPACE_HEIGHT * UP, SPACE_HEIGHT * DOWN) self.num_plane = NumberPlane(x_radius = SPACE_WIDTH/2) self.num_plane.to_edge(LEFT, buff = 0) self.num_plane.prepare_for_nonlinear_transform() self.add(self.num_plane, split_line) def squash_onto_left(self, object): object.shift(SPACE_WIDTH/2 * LEFT) def squash_onto_right(self, object): object.shift(SPACE_WIDTH/2 * RIGHT) def obj_draw(self, input_object): output_object = input_object.copy() if input_object.get_num_anchor_points() < self.num_needed_anchor_points: input_object.insert_n_anchor_points(self.num_needed_anchor_points) output_object.apply_function(self.func) self.squash_onto_left(input_object) self.squash_onto_right(output_object) self.play( ShowCreation(input_object), ShowCreation(output_object) ) def show_planes(self): right_plane = self.num_plane.copy() right_plane.center() right_plane.prepare_for_nonlinear_transform() right_plane.apply_function(self.func) right_plane.shift(SPACE_WIDTH/2 * RIGHT) self.right_plane = right_plane crappy_cropper = FullScreenFadeRectangle(fill_opacity = 1) crappy_cropper.stretch_to_fit_width(SPACE_WIDTH) crappy_cropper.to_edge(LEFT, buff = 0) self.play( ReplacementTransform(self.num_plane.copy(), right_plane), FadeIn(crappy_cropper), Animation(self.num_plane), run_time = 3 ) class DemonstrateColorMapping(ColorMappedObjectsScene): CONFIG = { "show_num_plane" : False } def construct(self): ColorMappedObjectsScene.construct(self) circle = cw_circle.copy() circle.color_using_background_image(self.background_image_file) ray = Line(ORIGIN, 10 * LEFT) ray.color_using_background_image(self.background_image_file) self.play(ShowCreation(circle)) self.play(ShowCreation(ray)) scale_up_factor = 5 scale_down_factor = 20 self.play(ApplyMethod(circle.scale, scale_up_factor)) self.play(ApplyMethod(circle.scale, fdiv(1, scale_up_factor * scale_down_factor))) self.play(ApplyMethod(circle.scale, scale_down_factor)) self.play(Rotating(ray, about_point = ORIGIN, radians = -TAU)) # TODO: Illustrations for introducing domain coloring # TODO: Bunch of Pi walker scenes # TODO: An odometer scene when introducing winding numbers # (Just set up an OdometerScene with function matching the walking of the Pi # creature from previous scene, then place it as a simultaneous inset with Premiere) class LoopSplitScene(ColorMappedObjectsScene): CONFIG = { # TODO: Change this to something more colorful down the midline "func" : plane_func_by_wind_spec((0.1/2, 1.1/2, 1), (-4.1/2, -1.3/2, 2), (1.8/2, -2.1/2, -1)), "use_fancy_lines" : True, } def PulsedLine(self, start, end, bullet_template, num_bullets = 4, pulse_time = 1, **kwargs): line = Line(start, end, **kwargs) if self.use_fancy_lines: line.color_using_background_image(self.background_image_file) anim = LinePulser( line = line, bullet_template = bullet_template, num_bullets = num_bullets, pulse_time = pulse_time, output_func = self.func, **kwargs) return [VGroup(line, *anim.bullets), anim] def construct(self): ColorMappedObjectsScene.construct(self) scale_factor = 2 shift_term = 0 # TODO: Change all this to use a wider than tall loop, made of two squares # Original loop tl = scale_factor * (UP + LEFT) + shift_term tm = scale_factor * UP + shift_term tr = scale_factor * (UP + RIGHT) + shift_term mr = scale_factor * RIGHT + shift_term br = scale_factor * (DOWN + RIGHT) + shift_term bm = scale_factor * DOWN + shift_term bl = scale_factor * (DOWN + LEFT) + shift_term lm = scale_factor * LEFT + shift_term loop_color = WHITE default_bullet = PiCreature(color = RED) default_bullet.scale(0.15) modified_bullet = PiCreature(color = PINK) modified_bullet.scale(0.15) def SGroup(*args): return VGroup(*[arg[0] for arg in args]) top_line = self.PulsedLine(tl, tr, default_bullet, color = loop_color) right_line = self.PulsedLine(tr, br, modified_bullet, color = loop_color) bottom_line = self.PulsedLine(br, bl, default_bullet, color = loop_color) left_line = self.PulsedLine(bl, tl, default_bullet, color = loop_color) line_list = [top_line, right_line, bottom_line, left_line] loop = SGroup(*line_list) for line in line_list: self.add(*line) self.wait() # Splits in middle if self.use_fancy_lines: split_line = Line(tm, bm) split_line.color_using_background_image(self.background_image_file) else: split_line = DashedLine(tm, bm) self.play(ShowCreation(split_line)) self.remove(*split_line) mid_line_left = self.PulsedLine(tm, bm, default_bullet, color = loop_color) mid_line_right = self.PulsedLine(bm, tm, modified_bullet, color = loop_color) self.add(*mid_line_left) self.add(*mid_line_right) top_line_left_half = self.PulsedLine(tl, tm, default_bullet, 2, 1, color = loop_color) top_line_right_half = self.PulsedLine(tm, tr, modified_bullet, 2, 1, color = loop_color) bottom_line_left_half = self.PulsedLine(bm, bl, default_bullet, 2, 1, color = loop_color) bottom_line_right_half = self.PulsedLine(br, bm, modified_bullet, 2, 1, color = loop_color) self.remove(*top_line) self.add(*top_line_left_half) self.add(*top_line_right_half) self.remove(*bottom_line) self.add(*bottom_line_left_half) self.add(*bottom_line_right_half) left_open_loop = SGroup(top_line_left_half, left_line, bottom_line_left_half) left_closed_loop = VGroup(left_open_loop, mid_line_left[0]) right_open_loop = SGroup(top_line_right_half, right_line, bottom_line_right_half) right_closed_loop = VGroup(right_open_loop, mid_line_right[0]) # self.play( # ApplyMethod(left_closed_loop.shift, LEFT), # ApplyMethod(right_closed_loop.shift, RIGHT) # ) self.wait() # self.play( # ApplyMethod(left_open_loop.shift, LEFT), # ApplyMethod(right_open_loop.shift, RIGHT) # ) self.wait() mid_lines = SGroup(mid_line_left, mid_line_right) highlight_circle = Circle(color = WHITE) # Perhaps make this a dashed circle? highlight_circle.surround(mid_lines) highlight_circle.stretch(0.3, 0) self.play(Indicate(mid_lines), ShowCreation(highlight_circle, run_time = 0.5)) self.wait() self.play(FadeOut(highlight_circle), FadeOut(mid_lines)) # Because FadeOut didn't remove the continual pulsers, we remove them manually self.remove(mid_line_left[1], mid_line_right[1]) # Brings loop back together; keep in sync with motions which bring loop apart above # self.play( # ApplyMethod(left_open_loop.shift, 2 * RIGHT), # ApplyMethod(right_open_loop.shift, 2 * LEFT) # ) self.wait() # Is there a way to abstract this into a general process to derive a new mapped scene from an old scene? class LoopSplitSceneMapped(LoopSplitScene): def setup(self): left_camera = Camera(**self.camera_config) right_camera = MappingCamera( mapping_func = lambda (x, y, z) : complex_to_R3(((complex(x,y) + 3)**1.1) - 3), **self.camera_config) split_screen_camera = SplitScreenCamera(left_camera, right_camera, **self.camera_config) self.camera = split_screen_camera # TODO: Perhaps do extra illustration of zooming out and winding around a large circle, # to illustrate relation between degree and large-scale winding number class FundThmAlg(EquationSolver2d): CONFIG = { "func" : plane_func_by_wind_spec((1, 2), (-1, 1.5), (-1, 1.5)), "num_iterations" : 2, "display_in_parallel" : True, "use_fancy_lines" : True, } class PreviewClip(EquationSolver2d): CONFIG = { "func" : example_plane_func, "num_iterations" : 5, "display_in_parallel" : True, "use_fancy_lines" : True, } # TODO: Borsuk-Ulam visuals # Note: May want to do an ordinary square scene, then MappingCamera it into a circle # class BorsukUlamScene(PiWalker): # 3-way scene of "Good enough"-illustrating odometers; to be composed in Premiere left_func = lambda x : x**2 - x + 1 diff_func = lambda x : np.cos(1.4 * (x - 0.1) * (np.log(x + 0.1) - 0.3) * TAU)/2.1 class LeftOdometer(OdometerScene): CONFIG = { "rotate_func" : left_func, "biased_display_start" : 0 } class RightOdometer(OdometerScene): CONFIG = { "rotate_func" : lambda x : left_func(x) + diff_func(x), "biased_display_start" : 0 } class DiffOdometer(OdometerScene): CONFIG = { "rotate_func" : diff_func, "dashed_line_angle" : 0.5, "biased_display_start" : 0 } class CombineInterval(Scene): def construct(self): plus_sign = TexMobject("+", fill_color = positive_color) minus_sign = TexMobject("-", fill_color = negative_color) left_point = Dot(LEFT, color = positive_color) right_point = Dot(RIGHT, color = negative_color) line1 = Line(LEFT, RIGHT) interval1 = Group(line1, left_point, right_point) plus_sign.next_to(left_point, UP) minus_sign.next_to(right_point, UP) self.add(interval1, plus_sign, minus_sign) self.wait() self.play( CircleIndicate(plus_sign), CircleIndicate(minus_sign), ) self.wait() mid_point = Dot(ORIGIN, color = GREY) question_mark = TexMobject("?", fill_color = GREY) plus_sign_copy = plus_sign.copy() minus_sign_copy = minus_sign.copy() new_signs = Group(question_mark, plus_sign_copy, minus_sign_copy) for sign in new_signs: sign.next_to(mid_point, UP) self.play(FadeIn(mid_point), FadeIn(question_mark)) self.wait() self.play( ApplyMethod(mid_point.set_color, positive_color), ReplacementTransform(question_mark, plus_sign_copy), ) self.play( CircleIndicate(plus_sign_copy), CircleIndicate(minus_sign), ) self.wait() self.play( ApplyMethod(mid_point.set_color, negative_color), ReplacementTransform(plus_sign_copy, minus_sign_copy), ) self.play( CircleIndicate(minus_sign_copy), CircleIndicate(plus_sign), ) self.wait() class CombineInterval2(Scene): def construct(self): plus_sign = TexMobject("+", fill_color = positive_color) def make_interval(a, b): line = Line(a, b) start_dot = Dot(a, color = positive_color) end_dot = Dot(b, color = positive_color) start_sign = plus_sign.copy().next_to(start_dot, UP) end_sign = plus_sign.copy().next_to(end_dot, UP) return Group(start_sign, end_sign, line, start_dot, end_dot) def pair_indicate(a, b): self.play( CircleIndicate(a), CircleIndicate(b) ) left_interval = make_interval(2 * LEFT, LEFT) right_interval = make_interval(RIGHT, 2 * RIGHT) self.play(FadeIn(left_interval), FadeIn(right_interval)) pair_indicate(left_interval[0], left_interval[1]) pair_indicate(right_interval[0], right_interval[1]) self.play( ApplyMethod(left_interval.shift, RIGHT), ApplyMethod(right_interval.shift, LEFT), ) pair_indicate(left_interval[0], right_interval[1]) self.wait() tiny_loop_func = plane_func_by_wind_spec((-1, -2), (1, 1), (1, 1)) class TinyLoopInInputPlane(ColorMappedByFuncScene): CONFIG = { "func" : tiny_loop_func, "show_num_plane" : False, } def construct(self): ColorMappedByFuncScene.construct(self) self.wait() circle = cw_circle.copy() circle.move_to(UP + RIGHT) self.play(ShowCreation(circle)) class TinyLoopInOutputPlane(TinyLoopInInputPlane): CONFIG = { "camera_class" : MappingCamera, "camera_config" : {"mapping_func" : point3d_func_from_plane_func(tiny_loop_func)}, "show_output" : True, "show_num_plane" : False, } class BorderOf2dRegionScene(Scene): def construct(self): num_plane = NumberPlane() self.add(num_plane) points = standard_rect + 1.5 * UP + 2 * RIGHT interior = Polygon(*points, fill_color = neutral_color, fill_opacity = 1, stroke_width = 0) self.play(FadeIn(interior)) border = Polygon(*points, color = negative_color, stroke_width = border_stroke_width) self.play(ShowCreation(border)) big_loop_no_zeros_func = lambda (x, y) : complex_to_pair(np.exp(complex(10, y * np.pi))) class BigLoopNoZeros(ColorMappedObjectsScene): CONFIG = { "func" : big_loop_no_zeros_func } def construct(self): ColorMappedObjectsScene.construct(self) points = 3 * np.array([UL, UR, DR, DL]) polygon = Polygon(*points) polygon.color_using_background_image(self.background_image_file) self.play(ShowCreation(polygon)) self.wait() polygon2 = polygon.copy() polygon2.fill_opacity = 1 self.play(FadeIn(polygon2)) self.wait() class ExamplePlaneFunc(ColorMappedByFuncScene): CONFIG = { "show_num_plane" : False, "func" : example_plane_func } def construct(self): ColorMappedByFuncScene.construct(self) radius = 0.5 def circle_point(point): circle = cw_circle.copy().scale(radius).move_to(point) self.play(ShowCreation(circle)) return circle def circle_spec(spec): point = spec[0] * RIGHT + spec[1] * UP return circle_point(point) nonzero_point = ORIGIN # Manually chosen, not auto-synced with example_plane_func nonzero_point_circle = circle_point(nonzero_point) self.wait() self.play(FadeOut(nonzero_point_circle)) self.wait() zero_circles = Group() for spec in example_plane_func_spec: zero_circles.add(circle_spec(spec)) self.wait() # TODO: Fix the code in Fade to automatically propagate correctly # to subobjects, even with special vectorized object handler. # Also, remove the special handling from FadeOut, have it implemented # solely through Fade. # # But for now, I'll just take care of this stuff myself here. # self.play(*[FadeOut(zero_circle) for zero_circle in zero_circles]) self.play(FadeOut(zero_circles)) self.wait() # We can reuse our nonzero point from before for "Output doesn't go through ever color" # Do re-use in Premiere # We can also re-use the first of our zero-circles for "Output does go through every color", # but just in case it would be useful, here's another one, all on its own specific_spec_index = 0 temp_circle = circle_spec(example_plane_func_spec[specific_spec_index]) self.play(FadeOut(temp_circle)) self.wait() class PiWalkerExamplePlaneFunc(PiWalkerRect): CONFIG = { "show_num_plane" : False, "func" : example_plane_func, # These are just manually entered, not # automatically kept in sync with example_plane_func: "start_x" : -4, "start_y" : 3, "walk_width" : 8, "walk_height" : 6, } class PiWalkerExamplePlaneFuncWithScaling(PiWalkerExamplePlaneFunc): CONFIG = { "scale_arrows" : True, "display_size" : True, } class TinyLoopOfBasicallySameColor(PureColorMap): def construct(self): PureColorMap.construct(self) radius = 0.5 circle = cw_circle.copy().scale(radius).move_to(UP + RIGHT) self.play(ShowCreation(circle)) self.wait() def uhOhFunc((x, y)): x = np.clip(x, -5, 5)/5 y = np.clip(y, -3, 3)/3 alpha = 0.5 # Most things will return green # These next three things should really be abstracted into some "Interpolated triangle" function if x >= 0 and y >= x and y <= 1: alpha = interpolate(0.5, 1, y - x) if x < 0 and y >= -2 * x and y <= 1: alpha = interpolate(0.5, 1, y + 2 * x) if x >= -1 and y >= 2 * (x + 1) and y <= 1: alpha = interpolate(0.5, 0, y - 2 * (x + 1)) return complex_to_pair(100 * np.exp(complex(0, TAU * (0.5 - alpha)))) class UhOhFuncTest(PureColorMap): CONFIG = { "func" : uhOhFunc } class UhOhScene(EquationSolver2d): CONFIG = { "func" : uhOhFunc, "display_in_parallel" : True, "manual_wind_override" : (1, (1, (1, None, None), None), None), # Tailored to UhOhFunc above "show_winding_numbers" : False, "num_iterations" : 5, } class UhOhSalientStill(ColorMappedObjectsScene): CONFIG = { "func" : uhOhFunc } def construct(self): ColorMappedObjectsScene.construct(self) new_up = 3 * UP new_left = 5 * LEFT thin_line = Line(UP, RIGHT, color = WHITE) main_points = [new_left + new_up, new_up, ORIGIN, new_left] polygon = Polygon(*main_points, stroke_width = border_stroke_width) thin_polygon = polygon.copy().match_style(thin_line) polygon.color_using_background_image(self.background_image_file) midline = Line(new_up + 0.5 * new_left, 0.5 * new_left, stroke_width = border_stroke_width) thin_midline = midline.copy().match_style(thin_line) midline.color_using_background_image(self.background_image_file) self.add(polygon, midline) self.wait() everything_filler = FullScreenFadeRectangle(fill_opacity = 1) everything_filler.color_using_background_image(self.background_image_file) thin_white_copy = Group(thin_polygon, thin_midline) self.play(FadeIn(everything_filler), FadeIn(thin_white_copy)) self.wait() # TODO: Brouwer's fixed point theorem visuals # class BFTScene(Scene): # TODO: Pi creatures wide-eyed in amazement ################# # TODOs, from easiest to hardest: # Minor fiddling with little things in each animation; placements, colors, timing, text # Initial odometer scene (simple once previous Pi walker scene is decided upon) # Writing new Pi walker scenes by parametrizing general template # (All the above are basically trivial tinkering at this point) # ---- # Pi creature emotion stuff # BFT visuals # Borsuk-Ulam visuals #################### # Random test scenes and test functions go here: def rect_to_circle((x, y, z)): size = np.sqrt(x**2 + y**2) max_abs_size = max(abs(x), abs(y)) return fdiv(np.array((x, y, z)) * max_abs_size, size) class MapPiWalkerRect(PiWalkerRect): CONFIG = { "camera_class" : MappingCamera, "camera_config" : {"mapping_func" : rect_to_circle}, "show_output" : True } class ShowBack(PiWalkerRect): CONFIG = { "func" : plane_func_by_wind_spec((1, 2), (-1, 1.5), (-1, 1.5)) } class Diagnostic(Scene): def construct(self): testList = map(lambda n : (n, rev_to_rgba(n)), [0, 0.1, 0.2, 0.3, 0.4]) print "Here you go:", testList self.wait() class DiagnosticColorMap(PureColorMap): CONFIG = { "func" : lambda (x, y) : (25 * x, 25 * y), "show_num_plane" : False, } class PiWalkerOdometerTest(PiWalkerExamplePlaneFunc): CONFIG = { "display_odometer" : True } class PiWalkerFancyLineTest(PiWalkerExamplePlaneFunc): CONFIG = { "color_foreground_not_background" : True } # FIN