MCG Ray to Surface Position and Orientation Constraints

The MCG Ray to Surface Position and Orientation Constraints command applies two constraints to set an object's position and orientation based on the intersection of a ray cast from another object onto one or more meshes. Unlike MCG Ray to Surface Transform Constraint, it does not affect scaling.

• Animation menu > MCG Controllers > MCG Ray to Surface Position Constraint
• Assign Controller (object Position track) > MCG_rayToSurfacePosition and Assign Controller (object Rotation track) > MCG_rayToSurfaceOrientation

1. Prepare at least three objects:
   • An object to constrain.
   • A mesh to constrain to.
   • An object to serve as the ray origin.
2. Select the object to constrain.
3. Choose Animation menu > MCG Controllers > MCG Ray to Surface Position Constraint.
4. Click the surface mesh.
5. Click the ray origin object.
6. If desired, you can use Pick Surface to add more mesh surfaces.

Alternatively, you can use Assign Controller on the object's Position and Rotation tracks in the Track View or Motion Panel to assign MCG_rayToSurfacePosition and MCG_rayToSurfaceOrientation manually, and then use the Pick Surface and Ray Cast Object buttons to specify the appropriate objects.

Interface

Ray to Surface Position

See MCG Ray to Surface Position Constraint.

Ray to Surface Orientation

Cast Ray To

Pick Surface

Click to select additional meshes.

[surface list]

Lists the meshes.

Remove Selected

Select an object in the list, and then click this button to remove it.

Ray Cast Object

Ray Cast Object

Click this button to select an object in the scene to serve as the ray origin.

Aim at Surface Pivot

When activated, rays are cast from the ray cast object's center to the centers of the surfaces. Otherwise, a ray is cast along one of the ray cast object's local axes.

Ray Axis

The direction of the ray cast from the ray cast object, when Aim at Surface Pivot is off.

Local Up Axis

Specifies which local axis of the object to align with the surface normal or ray.

Local Forward

Specifies which local axis of the object to align with the world forward axis or forward object.

Orientation Parameters

Use Surface Normal

Aligns the object's local up axis with the normal of the mesh surface at the ray intersection. When this option is off, the object is aligned with the ray instead.

Use Forward Object

Aligns the object's local forward axis to point at the forward object. When this option is off, or when the forward object is not defined, the object is aligned with the world instead.

Forward Object

Click to select an object to point the constrained object's local forward axis at.

World Forward Axis

The world axis to align the object's local forward axis with, when not using a forward object.