Rhino 8 QuadRemesh guide: clean quad meshes and a SubD workflow

In Rhino 8, the QuadRemesh command generates a remeshed quad mesh from existing surface, mesh or SubD geometry. According to McNeel’s official documentation, the command is designed to create manageable polygon meshes for uses such as rendering, animation, CFD, FEA and reverse engineering. The steps below explain how to choose settings based on the model’s shape and intended use.

1. Choose a target: edge length or face count?

1. Run the QuadRemesh command. The documented command path is SubD / Mesh > Edit Tools > Quad Remesh.

2. To control the approximate size of the output faces, use Target Edge Length. This setting depends on scale: the same target edge length does not produce a similar face count for objects at different scales. The documentation notes that remeshing may fail if the target edge length is set too large relative to the object.

3. If controlling the approximate face count is the priority, choose Target Quad Count. This setting is scale-independent: it targets a similar face count for the same input object, even at different scales.

These two options address different needs. Edge length is more useful when you want to maintain a particular level of geometric detail; a face-count target makes more sense when you want to set an approximate polygon budget. The result is still an algorithmic target—the setting names also make clear that the values are approximate.

2. Adjust adaptive size and face density

1. Choose an Adaptive Size (0-100) value based on the model’s detail requirements. According to the documentation, 0 favors the fewest quads with similar sizes. As the value increases, smaller faces are created in areas of high curvature; 100 can be used to preserve more detail.

2. Increase the value cautiously if keeping the face count low is important. McNeel notes that above 30, control over obtaining fewer quads decreases. For that reason, consider higher values when preserving intricate curves matters more than limiting the face count.

3. Inspect the result with Preview. The preview updates as settings change and provides information about average edge length and face count. This helps you compare the output with your target before confirming the operation.

3. Manage edge flow and hard transitions

1. Use Use Surface Edges to define how polysurface or extrusion boundaries are handled in the mesh. Off ignores these boundaries. Smart preserves most of them while excluding those the algorithm considers meaningless. Strict preserves all polysurface boundaries. Compare these options in the preview when boundaries matter.

2. Use guide curves to direct quad flow in specific areas. The curves must be projected onto the geometry; otherwise, they have no effect on the result. Approximate lightly influences the general direction of the quads. Create Edge Ring attempts to create edge rings perpendicular to the curves. Create Edge Loop places edge loops along the curves and gives the guides their strongest effect.

3. Consider the Detect Hard Edges option at sharp transitions. It adds a hard edge loop to the quad mesh when the angle between adjacent faces exceeds 30 degrees. Turn it off if the input mesh is irregular or you don’t want these kinds of edges in the output mesh.

4. Convert the quad mesh to SubD

1. To use the QuadRemesh result as a SubD, turn on Convert to SubD. This converts the quad mesh into a smoothed, curved surface while preserving hard edges where possible. SubD Creases transfers detected hard edges to creased edges in the SubD. SubD corners converts corner points in the quad mesh into SubD corners.

2. Check how the Interpolate SubD setting affects the model. When enabled, the quad mesh vertices are used as SubD points, and the SubD passes through the quad mesh. The documentation describes this approach as generally suited to reverse engineering. When disabled, the mesh points become control polygon points; the result may be somewhat smaller or larger than the input shape.

3. To convert independently of QuadRemesh, use the ToSubD command. The documentation lists mesh, extrusion, surface and polysurface as supported input types. When converting a mesh, the ControlPoints and Location modes of the UseMesh option determine whether mesh vertices become SubD control points or SubD points. MeshCreases controls whether unwelded edges in the source mesh are converted to creased edges. MeshCorners determines whether a corner vertex on the boundary of a quad mesh face is creased or smooth.

There is also an important limitation to keep in mind when using ToSubD: surface trims are not carried over to the SubD. The individual surfaces in a polysurface are converted separately; non-manifold mesh edges and their associated faces are removed. Checking the geometry before conversion and inspecting the resulting SubD can help catch unexpected differences early.

What changes in architecture and archviz workflows?

QuadRemesh can be useful for architecture and visualization teams looking to convert organic forms, complex surfaces or existing meshes into more regular quad topology. The documentation lists rendering and animation as possible uses; CFD, FEA and reverse engineering are also among the stated applications. Guide curves can be used to direct edge flow in specific areas of a model.

Still, no single setting works for every model. Scale, target face count, detail to preserve and the need for hard edges all affect the result. For irregular input meshes in particular, check Detect Hard Edges and how the surface behaves after conversion. Since the Rhino 8 documentation does not specify hardware requirements or licensing conditions, this guide makes no additional assumptions on those points.

Common mistakes

• Setting Target Edge Length without taking the model’s scale into account. If the target is too large relative to the object, the operation may fail.

• Increasing Adaptive Size for more detail without considering that this can reduce control over the face count.

• Using guide curves without projecting them onto the geometry; in that case, the curves have no effect on the mesh.

• Assuming trims will be preserved during ToSubD conversion. According to the documentation, surface and polysurface trims are lost in the SubD.