Hybrid Worlds:
Formula Mixing, dIFS & Volumetric Light
Go beyond single formulas: stack and alternate formula sets, sculpt with dIFS geometry, and light it all with cinematic volumetrics.
Quick Answer: On the Formulas tab, load several formulas in sequence and set each one’s iteration count — MB3D alternates between them per iteration, creating hybrid fractals. Add dIFS formulas for crystalline architecture, then finish with volumetric light and fog for cinematic depth.
Step 1 — Build Your First Hybrid
Open the Formulas tab. Instead of one formula, choose several in the formula slots — for example Mandelbox followed by Menger Sponge. MB3D calculates them in sequence: each formula is repeated n times according to its ‘iteration count’ value before the next one takes over, producing an alternating hybrid neither formula makes alone.
Set an iteration count to zero to deactivate a formula without removing it, or pick the empty field in the dropdown to remove it entirely. The ‘Repeat from here’ option controls where iteration restarts after the last formula — use it to run a formula once as an “intro” that never repeats.
Watch for formula names starting with an underscore (_): these are designed only for alternating hybrids and will not produce anything sensible on their own.
Step 2 — Sculpt with dIFS
dIFS (deterministic iterated function systems) is the geometry behind Sierpinski gaskets and Menger sponges — crisp, crystalline, architectural structures with razor-sharp edges, a striking contrast to the organic swirls of escapetime fractals.
Try a dIFS formula as the second slot in a hybrid: run 2–3 iterations of Mandelbox first, then switch to the dIFS set. The result is the classic MB3D look — organic mass wrapped in crystalline scaffolding. Adjust the R bailout carefully here: too low and you get artifacts on the sharp edges.
Step 3 — Volumetric Light & Fog
Open the Coloring → Volumetric light tab. Volumetric lighting simulates light scattering through the scene — god-rays in tunnels, glowing fog in cavities. Raise the density slowly: a little goes a long way, and heavy volumetrics multiply render time.
Combine it with Ambient Shadows (post-processing) for contact depth in crevices, and Hard Shadows for crisp directional definition. The two shadow systems stack — that combination is what gives MB3D renders their signature cinematic weight.
Step 4 — Custom Texture Maps
MB3D can map external images onto your fractals as color or lighting maps. Prepare a seamless texture, load it in the map slots, and experiment with mapping modes — a subtle noise texture on a hybrid structure can turn clean math into weathered alien architecture. The community shares curated map packs on FractalForums.
Pro tip: hybrid exploration is a numbers game. Render small previews (low resolution, low iterations), save every interesting .m3p, and only commit to a full-quality render — optionally with the Monte Carlo renderer for true global illumination — once the composition is locked.
Keep going: Level 03: Cinematic Motion turns your stills into animation — or revisit Level 01: Essentials.
Frequently Asked Questions
What is a hybrid fractal in Mandelbulb 3D?
A hybrid alternates between two or more different formulas during iteration — e.g. several iterations of Mandelbox followed by several of Menger Sponge. The result is a structure neither formula produces alone, and it is MB3D’s signature capability.
Why do some formulas start with an underscore?
Underscore-prefixed formulas are built only for use inside alternating hybrids — they are not intended to render meaningfully on their own. Use them as secondary slots in a hybrid stack.
My hybrid render has strange artifacts. What causes that?
The most common cause is an R bailout value set too low for the formula combination. Raise it gradually until the artifacts disappear, and check that iteration counts are not starving any single formula.
Volumetric light makes renders extremely slow. Any tips?
Keep volumetrics off while composing — enable them only for the final render. Lower the density first, and consider rendering the volumetrics as a separate pass you composite later.