Rhino 8 QuadRemesh Guide: Quad Mesh and SubD Workflow

The QuadRemesh command, described in McNeel’s official Rhino 8 documentation, creates a quad mesh with editable topology from existing surfaces, meshes, or SubD objects. Its location is shown as SubD / Mesh > Edit Tools > Quad Remesh. The steps below explain the core options, from setting mesh density to converting the result to SubD.

1. Choose the input geometry and target density

First, select the object to convert and run QuadRemesh. The command creates quad meshes for a range of potential uses; Rhino’s documentation lists rendering, animation, CFD, FEA, and reverse engineering as examples. That does not mean the output will automatically be ideal for each of these tasks. Check the target face count and topology against the model’s intended use.

There are two main approaches to setting density:

• Target Edge Length: Sets an approximate target edge length for the output mesh. It depends on model scale; as the object gets larger, the resulting face count also increases. If the value is set too high relative to the object’s size, the operation may fail.

• Target Quad Count: Sets the approximate face count the algorithm will try to reach. It is scale-independent; the same input processed at different scales will target a similar face count.

When scene scale may vary, targeting a face count can make comparisons easier. Target Edge Length may be preferable when working toward a specific approximate edge size, but remember that this setting depends on model scale.

2. Manage face distribution and subsurface boundaries

Adaptive Size (0-100) affects the size and density distribution of faces. A value of 0 aims for fewer quads of more uniform size. As the value increases, smaller faces may form in areas of high curvature; 100 is intended to preserve more detail. The documentation notes that above 30, control over producing fewer quads may decrease.

Use Surface Edges applies only to polysurface and extrusion inputs. Off ignores subsurface boundaries. Smart preserves some boundaries while excluding those the algorithm considers meaningless; Strict keeps all subsurface boundaries. If you need to preserve boundaries, compare the options in the preview.

3. Shape the flow with guide curves and symmetry

Use Guide Curves if you want the mesh to flow in a specific direction or edge loops to follow defined curves. For the curves to have an effect, they must be projected onto the input object. The Curve Influence options determine how strongly the curves affect the result:

1. Approximate gives the natural flow of the quads a gentle directional influence.

2. Create Edge Ring tries to orient edges that cross the curves perpendicular to them. Its influence is stronger, but the edge rings may not follow the curves exactly.

3. Create Edge Loop attempts to place edge loops along the curves and applies the strongest influence of the available options.

For a symmetrical model, you can enable the X, Y, or Z axis that matches the object’s center plane; you can also select more than one axis. This setting is meaningful only if the model is actually symmetrical and the selected plane is correct. Do not use it if these symmetry conditions are not met.

4. Check the preview and convert to SubD

Preview updates the result as you change settings; it also displays the approximate average edge length and face count. If the dense wireframe of the input object obscures the preview, you can use Hide Input Objects. Delete Input Objects determines whether the source objects are deleted when the operation is complete; check this option if you need to preserve the source geometry.

The Convert to SubD option in QuadRemesh converts the result to SubD. Separately, ToSubD supports mesh, extrusion, surface, and subsurface types. In the UseMesh options, ControlPoints converts mesh vertices to SubD control points, while Location converts SubD points to the locations of the mesh vertices.

QuadRemesh’s Interpolate SubD option also affects the output shape. When enabled, mesh vertices are used as SubD points, and the SubD passes through the quad mesh. When disabled, mesh vertices become control polygon points, and the result may be slightly smaller or larger than the input. SubD Creases preserves in the SubD the creased edges created by QuadRemesh’s Detect Hard Edges option. SubD corners converts corner points to SubD corners.

In the ToSubD options, MeshCreases determines whether unwelded mesh edges are converted to creased edges; MeshCorners determines whether the boundary corner point of a quad mesh face is creased or smooth. Trims may be lost when converting from a surface to SubD. Subsurfaces within a polysurface are converted individually; non-manifold mesh edges and their associated faces are removed.

Workflow for architecture, interior design, and visualization

Teams looking to convert a complex or curved form into an editable quad structure and then refine it with SubD can benefit from this workflow. Options for target face count, detail preservation, and edge flow make it possible to try different results based on the model’s needs. The documentation also lists rendering, animation, CFD, and FEA as use cases; it does not promise a specific performance gain or a suitable result for every project.

These settings are described in the Rhino 8 documentation; this does not establish support or compatibility for other versions. The sources do not provide information about hardware requirements, licensing terms, or costs. Before production, it is useful to test the input geometry type, projection of guide curves, mesh boundaries, and trim behavior during SubD conversion on a small sample.

Common mistakes

• Setting the target edge length too high for the model’s size: The remeshing operation may fail. As an alternative density approach, consider Target Quad Count, which targets an approximate face count.

• Not projecting guide curves onto the object: Unprojected curves do not affect the QuadRemesh result.

• Enabling symmetry on the wrong axis: The option is meaningful for symmetrical objects on the correct center plane.

• Not checking hard edges on an irregular input mesh: The documentation notes that Detect Hard Edges can be turned off for these inputs to avoid unwanted edges.

• Overlooking source geometry or surface trims during conversion: Check the Delete Input setting and ToSubD’s trim behavior before proceeding.