Renderbricker

Smooth, render-ready LEGO® parts from Mecabricks imports – without touching the imported meshes.

Renderbricker is a Blender add-on and a batch pipeline for scenes built in Mecabricks by Nicolas 'Scrubs' Jarraud and imported with his Mecabricks Lite or Advanced add-on. Each part mesh is processed once: seams are welded in a temporary copy, edges get creases by a tested rule set, and the subdivided result is baked into a copy that every link of that part uses. The original import stays unchanged, so the conversion can always be undone.

Features

• Rule-based creases – sharp where the real part is sharp, round where it is round; the rules are documented with the part and finding they come from in docs/RULES.md.
• One copy per part – thousands of links share one subdivided mesh; viewport and render level can differ (the render level is switched in for F12 and back afterwards).
• Cache file – the copies can live in <scene>_rbcache.blend next to the scene, linked as library overrides, so the scene file stays small; move or copy the cache with the scene, switch it off to take the copies back into the scene.
• Several Blender processes – Apply and the headless conversion share the parts among several Blenders in the background; how many depends on the processor and the free memory.
• Checks – the original is verified untouched, folds and seam gaps are measured after every conversion.
• Render camera – a camera, a physical sky and render settings of their own, switched on and off without touching yours: six views around the model, sun sliders, transparent background, sample levels, all views in one go.
• Cycles | EEVEE – either engine in the viewport and for rendering; EEVEE gets a sun lamp that follows the sky and comes close to Cycles.
• Real size – models imported at scale 0.001 (the metric real size) work like those at scale 1; the render camera follows scale changes.

Requirements

• Blender 4.5 LTS or newer (developed with 5.2 LTS and 5.3)
• Windows, Linux or macOS
• Scenes from www.mecabricks.com, imported with the Mecabricks Lite or Advanced add-on

Installation

1. Download renderbricker-<version>.zip from the latest release.
2. Blender: Edit → Preferences → Add-ons → Install from Disk → choose the zip, enable "Renderbricker"
3. Panel: 3D Viewport → Sidebar (N) → Renderbricker

To build the package from the source instead: python scripts/core/build_addon.py → addon/dist/renderbricker-<version>.zip

Documentation

• Quick start – the workflow in seven steps
• Tutorial – every step with pictures
• Reference – all settings and buttons
• Troubleshooting · Known issues · Glossary
• Rules – the rule set with the origin of every rule

Usage

• Apply converts all mesh objects (or the selection). Choose viewport and render level first; with "Cache file next to the scene" the scene is saved automatically once the cache is written.
• Subdivision: ON / OFF switches every link between the subdivided copy and the original.
• F12 / Ctrl+F12 render with the render level.
• Convert headless runs the conversion without the window (faster for large scenes).

Batch conversion of many models (system Python):

python scripts/core/convert_models.py [--models NAME ...] [--stale] [--force] [--jobs N]

It expects 01_Sources/<model>.zmbx beside the code, writes 02_Imports/ and 03_Results/<model>_subdiv_A_mecabricks_<version>.blend and checks every result. Blender is taken from RENDERBRICKER_BLENDER, a path in _CLAUDE_/blender_path.txt or blender on the PATH; --blender PATH overrides all.

Feedback

• Ideas and suggestions: Discussions → Ideas – others can comment and vote.
• Questions: Discussions → Q&A
• Your renders: Discussions → Show and tell
• Bugs: Issues – with the Renderbricker and Blender version and, if you can, the log file (option Log file in the panel).

Repository layout

addon/renderbricker/       Blender add-on: registration and UI modules
addon/renderbricker/rbcore/  the core: crease rules, conversion, copies, cache, workers, render camera
scripts/core/              batch conversion, import, verification
docs/RULES.md              the rule set with the origin of every rule

Model files, results and the development journal are kept locally beside the code and are not part of the repository.

Author

© 2026 Renderbricks® – Prof. Michael Klein.

Transparency note on the use of AI: the author is not a programmer but has worked in CGI since 1987. The add-on was developed entirely through vibe coding with Anthropic Claude (Claude Code): Claude wrote the code, the tests and this documentation from his descriptions. The concept, the design decisions, the rules checked against the real LEGO parts, the tests in Blender and the acceptance of every version are the author's; he is responsible for the content.

www.renderbricks.com · Facebook · YouTube

Renderbricks® is a registered word mark in Germany.

Credits

Renderbricker is built on Mecabricks and its Blender add-ons Mecabricks Lite and Mecabricks Advanced – their developer and creator is Nicolas 'Scrubs' Jarraud.

The example scene of the Tutorial is the Italian Riviera by Nicolas 'Scrubs' Jarraud, used with his kind permission – thank you for the model.

License

GPL-3.0-or-later, see LICENSE.

LEGO® is a trademark of the LEGO Group; all other names and marks mentioned here belong to their owners, none of whom sponsors, authorizes or endorses this project.