anchor.diff:      ;; change box
       ;; (in future we can look up based on some hash)
       (setf (%sampler-id-box sampler)
  -          (make-sampler-id-box :id (%get-id))))
  +          (make-sampler-id-box :id (%get-id) :shared-p nil)))
     sampler)
   
   
  
positive.code:       (format stream "#<SAMPLER :UNINITIALIZED>")))
  
  (defun+ free-sampler (sampler)
    (unless (sampler-shared-p sampler)
      ;; Be sure to add this back in when you implement freeing
      ;; samplers.
      (warn "CEPL: free-sampler not yet implemented~%leaking ~s"
            sampler)))
  
  (defmethod free ((sampler sampler))
    (free-sampler sampler))
  
negative.code:   (let ((wrap (if (keywordp wrap)
                    (vector wrap wrap wrap)
                    wrap)))
      (if (and (= lod-bias 0.0)
               (= min-lod -1000.0)
               (= max-lod 1000.0)
               (eq minify-filter :linear)
               (eq magnify-filter :linear)
               (wrap-eq wrap #(:repeat :repeat :repeat))
               (eq compare :none))
          *default-sampler-id-box*
  