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I'd like to use a few bones to control a path, so I tried binding the path to the bones using weights but the auto calculation is not available (see the screenshot). I tried simpler paths with two to three bones, but it still didn't work. The "auto" button is always grey for any path with any bones.
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I can paint the weights, but the auto calculation is not available. That button is always grey.
Very frustrating! Does anyone know why? Thank you.