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recycleFeedback Loops

Each change, becomes everything.

Feedback loops are where Nodalin gets wild. A feedback loop happens when the result of one frame becomes part of the next. This creates motion trails, echoes, smears, pulsations — visuals that evolve instead of simply updating. It’s one of the most powerful things you can do in Nodalin.

How feedback (usually) work

In most node-based apps, building a feedback loop means assembling a mini-architecture:

  • a node to capture the previous frame

  • a node to send it back

  • a node to blend it with the new frame

  • plus whatever effect nodes must sit inside the loop

It works, but it’s fragile and gets messy quickly.

How Nodalin does it

In Nodalin, all of this collapses into one node: Post.

Every frame, Post:

  1. Takes a snapshot of what was drawn

  2. On the next frame, mixes that snapshot with the new frame

  3. Outputs the blend so the loop continues

Since each new frame carries a trace of the last, your scene gains a sense of memory. Patterns stretch, duplicate, melt, or jitter depending on how you mix them.

Feedback isn’t just repetition — it’s accumulation.

Blend In to Stand Out

As mentioned earlier, the Post node blends the previous and current frame using modes similar to the Blend node. This opens up fun creative options — including using Post as a post-processing effect for glow, bloom, or brightness boosts.

To brighten the image, switch its blending mode (right-click the Post node) to something light-friendly:

  • Screen adds gentle glow and lift

  • Linear Dodge (Add) builds intense highlights and bloom

  • Others — Overlay, Color Dodge, Color Burn — each have their own energy

On top of the blend mode, Post includes:

  • Opacity, to control how much of the past leaks into the present

  • Scale, which shrinks or enlarges the previous frame to create outward or inward trails

  • Gain, which boosts brightness and exaggerates pixel structure

Simple controls — a lot of possibilities.

Embrace the Difference

This chapter title isn’t just a pun. If you’ve ever used a photo editor, you’ve probably skipped the blending mode always sitting at the bottom: Difference.

It looks chaotic and hard to control — which is exactly why it shines in feedback loops.

Difference works by subtracting pixel values between frames. With something moving, that means it only reveals change. What you see is the “leftover shape” — the pieces no longer overlapping. It’s like drawing with the gaps.

This naturally produces visuals that feel almost biological. Once the output is fed back into itself, tiny shifts get amplified and spread, creating structures reminiscent of diffusion–reaction systems… but without the simulation cost or math.

Example Projects

Blend Stellarinarrow-up-right All the glitching artifacts are driven by a single Post node.

Flock Of Feedbackarrow-up-right Using a single Post node and just a couple of Effects

Statix Datainarrow-up-right

Static Datarin Remixarrow-up-right Exactly the same graph as the original project, with a few tweaks.

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There can also be data-based feedback (numbers or values feeding back into themselves). Learn more on our Wave node reference.

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