Stager can import many common formats from CAD (Computer Aided Design) software. Stager provides some special import settings and workflows when working with CAD data. See import & export formats for a full list.

CAD import settings

Tessellation level

3D modeling applications have a few underlying technology types. There are some tools like Maya, 3DS MAX, and ZBrush that primarily work on polygon based infrastructure where every surface is created from small triangles. CAD tools usually are more mathematically based, and build models from surfaces, curves, and intersection logic. Stager is a polygon based rendering tool, so when you import CAD data the original surfaces and curves are converted into polygon and triangle based meshes.

Tessellation is a general concept in 3D that controls how many triangles are used to represent a mesh. Increasing tessellation divides each polygon (usually a triangle) into two, many times over. Higher tessellation results in smoother curve and surface representation and more detail for displacement workflows, but at the cost of adding more polygon geometry.

When importing your CAD data you'll first be asked to choose a tessellation level. Lower tessellation levels result in less smooth curves, but faster general performance. Higher tessellation will result in smoother curves, but may be slower especially for complex models. Generally the larger your CAD data set the lower your resolution may need to be to work with it at performant speeds.

Left: A CAD model imported at extra low tessellation quality. Right: The same CAD model imported at medium tessellation quality.

Generate UVs

Stager has two ways to apply materials to models: UV projection and triplanar projection. For more details on both UV and triplanar workflows in Stager see material projections.

Most CAD software does not utilize UVs so most CAD models will not have them. You can use the triplanar projection workflow without generating UVs. Triplanar projection benefits are that it is usually faster, can be represented in real world physical units more easily, and can blend the seams where the material meets. Projection workflows work well when working with materials with less patterns, like plastics, metals, papers, and other generally uniform materials. It can also work with some materials that have some pattern in it like wood or fabric.

Learn more about material projections in Stager.

Left: Materials applied in UV projection mode. Seams will show hard lines where textures meet. Right: Materials applied in triplanar projection mode. Seams can be blended to improve results.

When importing your CAD model, you can also choose to automatically generate UVs for any parts that don't have UVs. Stager will use the CAD surfaces to provide improved automatic UV generation and layout, based on the original CAD information. This can often provide great automatic UV results without any additional manual UVing needed. Automatic UVs can sometimes provide better seam placement based on the geometry edges and curve data, but seams cannot be blended.

There are limits to both automatic UV generation and triplanar projection workflows. If you need to line up edges of graphics very specifically you may need to go through the additional step of manually creating UVs for your model. This can be done in most 3D modeling software like Maya, Blender, Cinema 4D, and more.