Rotation Constrained

The Rotation Constrained panel (VIEW3D_PT_rotation_constrained) performs a controlled bend on selected mesh faces by rotating them around one axis while constraining the vertex motion along another. It is the preferred tool for hinging panels, opening swing-out elevations, or modelling the rotation of a fragment around a known pivot edge.

This page is the parameter and operator reference for the panel.

Source: utils/rotation_constrained.py. Sidebar tab: 3DSC. Default state: collapsed (DEFAULT_CLOSED). Visible only when the active object is a mesh.

Required state

The panel walks the user through two prerequisites before exposing the operator:

  1. The mesh must be in Edit Mode (the panel offers a shortcut button to enter it).

  2. At least one face must be selected (the panel offers a shortcut to switch to face select mode).

Parameters

Rotation Axis (rc_raxis)

Pivot axis for the rotation (X, Y or Z).

Constraint Axis (rc_caxis)

Axis along which the moved vertices are allowed to travel. Must be different from Rotation Axis — if equal, the panel shows a warning and the operator refuses to run.

Rotation Point (rc_rpoint)

Pivot anchor used for the rotation (typically the median of the selected edge — refer to source for the supported enum values).

Mirror (rc_rmirror)

When enabled, mirrors the rotation around the chosen pivot to produce symmetrical bends.

Degrees (rc_rdeg)

Rotation amount in degrees. A value of 0 is treated as a no-op and reported as such.

Operators

mesh.apply_rotation_constrained — Apply Rotation

Validates the selection and the axis configuration, then calls mesh.rotation_constrained with the panel parameters.

mesh.rotation_constrained

The underlying low-level operator. Can be invoked directly or via the Alt + Shift + R keyboard shortcut documented in the panel.

Typical workflow

  1. Enter Edit Mode on the target mesh.

  2. Select one or more faces representing the moving panel.

  3. Pick Rotation Axis (the hinge) and Constraint Axis (the direction the free edge is allowed to travel along).

  4. Set Rotation Point and Degrees; toggle Mirror if needed.

  5. Press Apply Rotation, or use Alt + Shift + R.

Remember

Rotation Axis and Constraint Axis must always be different — otherwise the rotation is geometrically undefined. The panel surfaces this with an inline warning, but no movement happens until the configuration is valid.