---
title: Chisel
order: 1
---

Chisel turns Blender into a real-time SDF modeling studio. Carve with math, not meshes. Every surface is mathematically smooth, every boolean blends like molten metal, and the ray-marched viewport shows the final result as you sculpt.

## First-run shader compilation

The first time you enable the Chisel render engine in a session, the GPU compiles the ray-marching pipelines on the fly. **Expect a noticeable pause on the first viewport frame**, typically a couple of seconds on Vulkan, longer on OpenGL. Compilation runs in parallel and is non-blocking, but the viewport will look empty until the first variant is ready.

A few things to know:

- **It's a one-time cost per session.** Subsequent renders use the cached pipeline. The compiled binaries are also persisted to disk, so warm starts after the first run are much faster.
- **Vulkan is dramatically faster than OpenGL.** If your status bar shows the OpenGL backend, switch to Vulkan in Blender's preferences (`Edit → Preferences → System → Backend`) for a 5–10× compile and runtime speedup.
- **The pie menu warns you.** When you press `Q` before shaders are ready, the menu shows *"Shaders not compiled, first run may take longer"*, and if you are on the OpenGL backend, *"OpenGL backend, Vulkan is much faster"*.

If you ever see flat shading, blank silhouettes, or stalls on the first interaction with a new feature (booleans, mirrors, curve primitives), it's almost always shader compilation finishing in the background. Wait a few seconds and the viewport will catch up.

## Why SDFs?

Traditional mesh modeling trades resolution for smoothness. SDFs don't trade. They compute. A sphere stays spherical at any scale, a blend stays blended through every boolean in the stack, and a rounded corner is a math constant, not a subdivision setting. Production-ready surfaces, no topology headaches.

## What's new in v4.1 (4.1.0)

Version 4.1 is about **shaping**. Five new modifiers bend, sweep, carve, revolve and smooth your models, the bisect plane grows handles, and Chisel now tracks GPU memory so heavy scenes slow down rather than fail.

- **[Smooth](modifiers/smooth.md)**: one radius rounds the whole model. Every join, edge and bevel sharper than the radius rounds up to it; anything you already made rounder keeps its own value
- **[Lattice](modifiers/lattice.md)**: bend and stretch a shape with a cage of points you drag in the viewport
- **[Carve](modifiers/carve.md)**: cut with a grown copy of another shape. The cutter stays visible, sitting in the pocket it carved
- **[Revolve](modifiers/revolve.md)**: spin a profile around an axis for rings, vases and turned parts
- **[Sweep](modifiers/sweep.md)**: run a shape along a path of points, with exact fillets at every corner
- **[Bisect handles](modifiers/bisect.md#gizmo)**: slide the cutting plane, drag the blend ring, round each polyline corner
- **[Gizmo visibility](render-engine/gizmos.md)**: dots and the Ngon gizmo follow the active object, all selected objects, or stay off
- **[Clean Mods](operations/clean-mods.md)** and **[Convert Legacy Curve](operations/convert-legacy-curve.md)**: one click to drop broken modifier rows, one click to turn an old curve shape into an Ngon, Revolve or Sweep
- **[Subdivision Level](render-engine/quality.md#brick-detail)** and **[Auto Cell Size](render-engine/performance.md#auto-cell-size)**: one detail slider for the whole scene, and detail that no longer depends on how big you built the object
- **[Mesh shapes that fit your GPU](primitives/mesh.md#when-a-grid-does-not-fit)**: a conversion that would not fit is refused up front, naming the largest resolution that does, and a shape that cannot be shown draws as a box instead of a blank scene
- **Undo no longer loses a shape's material**: the Chisel material now lives on the object, so proxy swaps and undo keep it

For a complete list, see the [changelog](changelog.md).

## Where to start

- [Getting Started](getting-started/index.md): install Chisel, system requirements, first launch
- [Primitives](primitives/index.md): every SDF shape and its parameters
- [Modifiers](modifiers/index.md): booleans, carve, mirror, bisect, array, solidify, emboss, twist, bend, revolve, sweep, lattice, smooth
- [Rounding & Blending](rounding-and-blending/index.md): the five profiles and when to use each
- [Materials](materials/index.md): per-object color and the Chisel node editor
- [Render Engine](render-engine/index.md): viewport quality, matcap, proxy mesh, baking
- [Interface](interface/index.md): panels, pie menu, active tool, gizmos
- [Operations](operations/index.md): convert to mesh, convert to SDF, apply, rebuild, clean, convert legacy curve, veil