Animation beyond imagination. Give life to cutscenes.
The Orchestrator creates smooth animations and sequences by applying effects to Transform objects over time.
The Orchestrator manages effects — transformations applied to objects over time. Unlike manual animation, effects automatically interpolate values, perfect for:
Create an orchestrator with a target object:
# Create a transform to animate
transform = kn.Transform(pos=kn.Vec2(100, 300))
# Create orchestrator targeting the transform
orch = kn.Orchestrator(transform)
The target must be a Transform object.
Chain effects with then() for sequential animation:
from pykraken import fx
# Create a bouncing ball animation
(
orch.then(fx.move_to(kn.Vec2(400, 100), dur=0.5))
.then(fx.move_to(kn.Vec2(400, 500), dur=0.5))
.then(fx.scale_to(kn.Vec2(1.2, 0.8), dur=0.1)) # Squash
.then(fx.scale_to(kn.Vec2(0.8, 1.2), dur=0.1)) # Stretch
.then(fx.scale_to(1.0, dur=0.1))
)
Run multiple effects simultaneously with parallel().
The duration of the parallel block is determined by the longest effect.
from pykraken import fx
# Move and rotate at the same time
# Entire sequence lasts 1.2 seconds
orch.parallel(
fx.move_to(kn.Vec2(600, 300), dur=1.0),
fx.rotate_to(180 * kn.math.DEG2RAD, dur=1.2),
)
Effects returned by factory functions like fx.move_to, fx.rotate_to, and fx.scale_to are single-use objects.
When you pass an effect to then() or parallel(), that orchestrator consumes it as part of its timeline.
That means this is the right pattern:
orch.then(fx.move_to(kn.Vec2(400, 100), dur=0.5))
orch.then(fx.move_to(kn.Vec2(100, 300), dur=0.5))
Avoid reusing the same effect object in multiple timeline steps:
hop = fx.move_to(kn.Vec2(400, 100), dur=0.5)
orch.then(hop)
orch.then(hop) # Do not reuse an already-consumed effect.
If you intentionally want the same effect settings in more than one place, clone it before giving it to another timeline step:
hop = fx.move_to(kn.Vec2(400, 100), dur=0.5)
orch.then(hop.clone())
orch.then(hop.clone())
See Effect.clone for the API reference.
Add easing for natural motion:
from pykraken import fx
# Smooth start and end
orch.then(fx.move_to(
kn.Vec2(700, 300),
dur=1.0,
ease=kn.ease.in_out_quad
))
# Bouncy ending
orch.then(fx.move_to(
kn.Vec2(100, 300),
dur=1.0,
ease=kn.ease.out_bounce
))
# Elastic overshoot
orch.then(fx.scale_to(
1.5,
dur=1.0,
ease=kn.ease.out_elastic
))
You can find more easing functions in the kn.ease submodule.
Before playing, you MUST finalize the orchestrator. This will prevent further changes and prepare the timeline.
# Finalize and play
orch.finalize()
orch.play()
The orchestrator updates itself every frame behind the scenes once played, which means no manual updating is necessary.
while kn.window.is_open():
kn.event.poll()
# Render using the animated transform
kn.renderer.clear()
kn.renderer.draw(texture, transform)
kn.renderer.present()
if orch.playing:
print("Animation is running")
if orch.finished:
print("Animation completed")
orch.pause() # Pause at current position
orch.resume() # Continue from paused position
orch.stop() # Stop and reset to beginning
orch.rewind() # Reset to beginning without stopping
Set looping for repeating animations:
orch.looping = True
orch.finalize()
orch.play() # Will loop when finished