Rendering Quality & Path Tracing

Two render engines

Switch between them in the Quality panel under "Render Engine Mode." Each suits a different use case.

Direct (Raymarching)

The fast, real-time mode. Up to 60 FPS on decent GPUs. Includes shadows, ambient occlusion, fog, and reflections.

Use when: exploring, editing, animating, anything interactive.

Path Tracer (Global Illumination)

Physically-based Monte Carlo rendering. The image starts noisy and clears over time as samples accumulate. Adds: global illumination (light bouncing off surfaces onto other surfaces), emissive lighting (glowing surfaces actually light the scene), soft area shadows.

Use when: producing final still images or photorealistic renders. Let the camera sit.

Quality panel — the main dials

Ray Detail (epsilon)

Controls how close to a surface a ray has to get before it "hits."

• 1.0 — standard (stop within 1 pixel of surface)
• < 1.0 — faster but blobbier; fine detail blurs into solid masses
• > 1.0 — sharper micro-detail but significantly slower

Internal Scale

Multiplies the render resolution.

• 0.25× – 0.5× — super fast, retro/pixelated. Great for editing on low-end GPUs.
• 1.0× — native resolution (default)
• 1.5× – 2.0× — super-sampling (SSAA). Kills aliasing but 4× the pixels to render.

Adaptive Resolution

Automatic quality scaling to maintain a target FPS (default 30). Drops resolution while moving the camera, restores when still. The top-bar icon shows the state — cyan (auto-restores) or amber (always-on while you're in panels). Disable it if you want locked full resolution, enable it for smooth interactive editing.

Path Tracer specifics

Once you switch to Path Tracer, a few specialized controls appear:

• Bounces — how many times light reflects. 2–4 is typical. Higher = brighter interiors but slower.
• GI Strength — artificial multiplier for bounce light. Useful to brighten deep caves without physically accurate solutions.
• Stochastic Shadows — treats lights as spheres (area lights) instead of points. Shadows get realistically soft. Requires accumulation to look smooth.

Render Region (partial accumulation)

Click the crop icon in the top bar and drag a rectangle in the viewport. The engine accumulates samples only within that region; pixels outside keep their current state. The overlay shows pixel size, sample count, and convergence — it goes green when the region is close to finished.

Essential for refining detail in one area without re-rendering the whole viewport.

High-quality render (Buckets)

Click the grid icon in the top bar for bucket rendering. The image renders in small tiles, each accumulating until converged before moving to the next. This is how you produce 4K and 8K images that would otherwise crash GPU memory.

• Refine View — cleans up the current viewport
• Export Image — renders at scaled resolution and downloads a PNG

Controls: Convergence Threshold (lower = cleaner, longer), Export Scale (2× = 4K from 1080p, 4× = 8K), Bucket Size (smaller uses less VRAM).

Advanced quality controls (backtick ` to reveal)

Press ` for Advanced Mode. Extra quality knobs appear:

• Max Steps — "fuel tank" per ray. Increase if distant parts are getting cut off (black void).
• Step Jitter — randomness per step. Breaks banding; averages out with accumulation.
• Step Relaxation — dynamic step size. Larger in open space, smaller near surfaces. Usually a performance win.
• Distance Metric — Euclidean (default), Chebyshev (cube-like), Manhattan (diamond-like), Minkowski (tunable blend).
• Distance Estimator — the math method. Leave on Analytic Log for most formulas; try Dampened if you see holes.

When things go wrong

• Holes or black speckles — overstepping. Reduce Fudge (slice optimization) below 1.0, or switch DE to Dampened.
• Grainy surfaces — stochastic features active (AO, shadows, PT) not yet accumulated. Hold still.
• Flat black regions — rays running out of Max Steps. Increase it.
• Puffy, blobby surfaces — Ray Detail too low. Increase toward 1.0 or above.