Setting Pivot Points in the PiXYZ Plugin

1. Setting the Pivot Point

This tutorial has been verified using Unity 2019 LTS and PiXYZ 2020.1.1.8

Depending on the original format of your imported model, your meshes may import without pivot information. In these cases, the pivot is at the center of the bounding box. (Figure 01) This is fine for models which are either static, or only rotate about their centers, but the majority of animated models will behave incorrectly with a centered pivot. The PiXYZ Plugin toolbox makes it quick to move the pivot, also known as the origin. In addition to a position relative to the mesh’s bounding box, the pivot can also be moved to a custom position in local (relative to the center of the mesh’s bounding box) or world space.

Figure 01: The pivot of a mesh defaults to the center of its bounding box when the pivot is not stored or specified in the imported model.

To move the pivot of a mesh, select Toolbox > Modify > Move Origin from the PiXYZ dropdown. (Figure 02)

Figure 02: Move Origin menu entry

There are four options for the pivot target: the minimum, center (default), or maximum of the mesh’s bounding box, or a custom location. The custom location can be either relative to the center of the mesh’s bounding box (local space), or in absolute (world) space. (Figures 03-04)

Figure 03: Options for the Move Origin operation.

Figure 04: Settings used for the door to place its pivot at the center of the bounding box

Set your options accordingly, and click Execute.

In addition to proper hierarchy, correct pivot location is essential to your animated meshes behaving as expected. If the model format doesn’t store the pivot location, PiXYZ Plugin makes it easy to set manually.