Chromatic Aberration Feedback

Inspired by: Okamirufu Vizualizer

The signature post-processing technique used by Okamirufu Vizualizer to give generative visuals a “rendered,” high-end feel. It uses time-delayed RGB splitting to create movement-based color separation.

Operator Families in this Recipe

• TOPs (Texture Operators): Time-based caching and feedback loops.

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Part 1: Movement-Based RGB Split

Instead of a static lens effect, this technique separates colors based on time, making fast-moving objects “ghost” in different colors.

1. Three Cache TOPs: Connect your final Render TOP to three Cache TOP nodes in parallel (connect the same output to all three).
   • Cache 1: Index → 0, Cache Size → 2 (current frame).
   • Cache 2: Index → -5, Cache Size → 10 (5 frames back).
   • Cache 3: Index → -10, Cache Size → 15 (10 frames back).
   • Note: Each Cache TOP must have a Size larger than the absolute value of its Index, or the indexed frame won’t exist yet.
2. Reorder TOP: Connect all three Cache TOPs to a Reorder TOP.
   • Output Red → Input 1 (current frame, Red).
   • Output Green → Input 2 (5 frames ago, Green).
   • Output Blue → Input 3 (10 frames ago, Blue).
3. The Result: You now have an RGB split that only appears when objects move.

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Part 2: Growth Feedback Loop

To make the visuals “bloom” and grow over time:

1. Feedback TOP: Connect your Reorder TOP to a Feedback TOP.
2. Transform TOP: Add a Transform TOP after the feedback.
   • Scale → 1.005.
   • Rotate → 0.1.
3. Level TOP: Add a Level TOP after the transform.
   • Opacity → 0.98.
4. Blur TOP: Add a Blur TOP after the level.
   • Filter Size → 2 (Small).
5. Composite TOP: Connect your Reorder TOP and the Blur TOP to a Composite TOP.
   • Operation → Screen or Add.
6. Close the Loop: Drag the Composite TOP back onto the Feedback TOP.

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Part 3: Final Polishing

1. Luma Blur TOP: Connect your composite to a Luma Blur TOP for a final soft glow.
2. HSV Adjust TOP: Use this to boost Saturation Multiplier and slightly shift the Hue for a more psychedelic feel.

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Troubleshooting

• “It’s getting too bright!” - Lower the Opacity on your Level TOP or the Brightness 1 of the feedback.
• “The trails aren’t moving.” - Make sure the Transform TOP has a non-zero Scale or Rotate.

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Parameter Tuning & Behavior

Parameter	Behavior
Cache Index offset	More negative values (e.g. -10 vs -2) = more pronounced time-based color separation (ghosting).
Feedback Scale	Higher = trails expand faster; Lower = tighter, more concentrated trails.
Feedback Rotation	Higher = more spiral-like motion in trails; Zero = straight expansion.
Level Opacity	Higher = trails persist longer (more “ghosting”); Lower = trails fade out quickly.
Blur Filter Size	Higher = softer, glowier feedback; Lower = sharper, more defined trail edges.

Network Architecture

To visualize how the data flows, here is a map of the final network:

[ INPUT ]
Render TOP
    │
    ├─▶ [ Cache TOP ] (Index  0, Size  2) ──┐
    ├─▶ [ Cache TOP ] (Index -5, Size 10) ──┼─▶ [ Reorder TOP ] (R, G, B Split)
    └─▶ [ Cache TOP ] (Index-10, Size 15) ──┘           │
                                                        ▼
[ TOP FEEDBACK LOOP ] ◀────────────────────────────────┘
    │
    ▼
[ Feedback TOP ] ──▶ [ Transform TOP ] ──▶ [ Level TOP ] ──▶ [ Composite TOP ]

📚 Learning Path · Stage 2 - Your First Visuals · step 12 of 44

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