Keyframes Spline Interpolator

Tutorial on making keyframe-based animation in FURY using Spline interpolators.

import numpy as np

from fury import actor, window
from fury.animation import Animation, Timeline
from fury.animation.interpolator import spline_interpolator

scene = window.Scene()

showm = window.ShowManager(
    scene, size=(900, 768), reset_camera=False, order_transparent=True
)

Position keyframes as a dict object containing timestamps as keys and positions as values.

position_keyframes = {
    0.0: np.array([0, 0, 0]),
    2.0: np.array([10, 3, 5]),
    4.0: np.array([20, 14, 13]),
    6.0: np.array([-20, 20, 0]),
    8.0: np.array([17, -10, 15]),
    10.0: np.array([0, -6, 0]),
}

creating FURY dots to visualize the position values.

pos_dots = actor.dot(np.array(list(position_keyframes.values())))

creating two timelines (one uses linear and the other uses’ spline interpolator), each timeline controls a sphere actor

sphere_linear = actor.sphere(np.array([[0, 0, 0]]), (1, 0.5, 0.2), 0.5)

linear_anim = Animation()
linear_anim.add_actor(sphere_linear)

linear_anim.set_position_keyframes(position_keyframes)

Note: linear_interpolator is used by default. So, no need to set it for this first animation that we need to linearly interpolate positional animation.

creating a second timeline that translates another larger sphere actor using spline interpolator.

sphere_spline = actor.sphere(np.array([[0, 0, 0]]), (0.3, 0.9, 0.6), 1)
spline_anim = Animation(sphere_spline)
spline_anim.set_position_keyframes(position_keyframes)

Setting 5th degree spline interpolator for position keyframes.

spline_anim.set_position_interpolator(spline_interpolator, degree=5)

Wrapping animations up!

Adding everything to a Timeline to control the two timelines.

First we create a timeline with a playback panel:

timeline = Timeline(playback_panel=True)

Add visualization dots actor to the scene.

scene.add(pos_dots)

Adding the animations to the timeline (so that it controls their playback).

timeline.add_animation([linear_anim, spline_anim])

Adding the timeline to the show manager.

showm.add_animation(timeline)

Now that these two animations are added to timeline, if the timeline is played, paused, …, all these changes will reflect on the animations.

interactive = False

if interactive:
    showm.start()

window.record(scene, out_path='viz_keyframe_animation_spline.png', size=(900, 768))