Koo Fruit Engine: Banana

Koo Fruit Engine in Materials and Shading


Pro tip — does using more markers give better results?
Counterintuitively, fewer markers usually produce a cleaner banana than many. If you're trying to match a specific shape (or wrapping the engine onto a non-banana subject — a cucumber, a portrait, anything elongated), reduce the silhouette polygon density. The 10 anatomical markers are usually enough to define the shape skeleton; the 38 silhouette markers refine outline. Many noisy markers over-fit and lock the shape into the photo's exact noisy pixels. A useful rule of thumb: 10 anatomical markers + 5 to 10 silhouette markers covers 90% of shapes cleanly.
What do the 10 anatomical markers mean?
The 10 anatomical markers define the banana's structural anatomy. Auto-trace places them automatically; manually adjusting them changes the generated mesh's shape directly. (1) Stem — the stem-end tip. The X-low endpoint of the central axis. (2) StemW up / StemW down — width boundary on either side of the stem cap. (3) Neck — the narrowing point where the stem cap transitions into the main body. (4) Thick up / Thick down — the two width boundary points at the banana's widest cross-section. (5) StigW up / StigW down — width boundary on either side of the stigma cap. (6) Stigma — the stigma-end tip (flower scar). Moving Stem or Stigma changes the length and axis; moving Thick changes body radius; moving StemW or StigW changes cap width; moving Neck changes taper sharpness. The remaining 38 markers form the silhouette polygon for outline refinement.
Auto-trace got the contour almost right but a few markers need nudging. How do I move them manually?
After Auto-trace Contour runs, the photo overlay on the right shows all 48 markers as colored circles. To move a marker manually: 1) Enable the Manual Trace toggle in the Image Source section (pencil icon next to Confirm). 2) Hover over the marker on the photo overlay; the cursor changes to a grab icon. 3) Click and drag the marker to its correct position. 4) Release to lock. 5) Repeat for any markers that need adjustment. When done, toggle Confirm to lock the corrected markers, then click Generate Realistic Banana to rebuild the mesh with the adjusted silhouette.
How does the photo-to-3D workflow work step by step?
1) Switch to the Realistic tab. 2) Image Source: click the folder icon and load a banana photo (png, jpg, webp). The photo appears on the right side with markers overlaid. 3) Click Auto-trace Contour — the bundled u2netp ONNX model runs in 1-2 seconds and extracts the silhouette, dropping 48 markers (4 anatomical: Stem, Stigma, StemW, StigW + 44 silhouette polygon, plus Neck and Thick reference points). 4) Review markers, toggle Confirm to lock. 5) Click Generate Realistic Banana — a procedural 3D banana matching the photo's outline, color, and curvature appears in about 4 seconds (Low quality). The photo skin is wrapped onto the peel automatically.
How do I use presets?
The Quality / Preset section has a dropdown listing built-in presets (preset_example_cavendish, preset_example_yellow, preset_example_aged, preset_example_pink, etc.). Select one and click Load — every slider on the panel jumps to that preset's values. The mesh is not rebuilt; click Apply Mesh Changes on the active banana to materialize the new values, or click Generate to build a fresh banana in a new slot. Save stores the current panel state as a new named preset; Save as creates a renamed copy. Preset files persist across Blender sessions.
What is mathematically grounded about it?
Every parameter has a documented mathematical or biological basis. Peel curl uses Euler-Bernoulli beam-bending physics. Stem packing follows constant-radius constraint at the natural neck transition. Aging models 13 biochemical state variables (chlorophyll, carotenoids, anthocyanin, polyphenol oxidase, etc.) via ODE integration. No magic numbers — every constant traces back to a paper or measurement.
How does the Shift+D cluster work? Are duplicates really independent?
Yes. The instant you click a Shift+D copy, the addon auto-renames it (banana_pinned_N.*) and detaches its mesh and material datablocks. Color, skin, deform, and Apply Mesh Changes affect only the active banana. Verified up to 40 bananas in a single scene without crosstalk.
What if auto-trace fails on my photo?
Two fallbacks. (1) Manually place the 48 markers by dragging them on the photo overlay. (2) Try the bundled preset banana from any tab (Stylized → Generate Stylized) without a photo. Auto-trace works best with a contrasting background; high-contrast natural backgrounds (table, cloth, wood) usually give clean silhouettes.
Can I use the bananas commercially?
Yes. The extension is GPL-3.0-or-later. Any output mesh, render, or animation is yours to use in commercial work without royalties. The GPL license only applies to the source code of the extension itself if you redistribute it.
Which Blender versions are supported?
Blender 4.2 LTS through 5.0+. Tested on Windows 5.0.1 and macOS Apple Silicon 5.0.1. Newer versions likely work but are not officially tested yet.
Do I need to install Python packages (Pillow, onnxruntime) myself?

No. All required wheels are bundled in the extension. Blender 4.2+

  automatically installs the right wheel for your platform (Windows, macOS Intel, macOS

   Apple Silicon, Linux) when you install the .zip. No pip install, no internet at

  runtime.

$9.99

Have questions about this product?
Login to message

Details
Blender Extension Compatible Yes
Published 4 months ago
Blender Version 4.2 - 5.0
Extension Type Add-on
Render Engine Used Cycles, Eevee
License GPL