Render > Place Projection

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Attaches a projective texture placement object to the bounding box of one or more objects.

Use this tool to ensure that projected textures don’t "swim" on objects if the objects are moved in an animation sequence.

To place a projective texture placement

Pick the projective texture placement object and the items that you want to snap to.
Choose Render > Place Projection or click its icon.
The texture placement object is snapped to the bounding box of the picked items.