Are parts of the code, especially those that are tutorials, even understood as copyrighted material?
Under the Berne convention anything put in a preservable form is automatically copyrighted, so yes.
Do I have to attribute to the author?
Seeing as that's the entire point of the license, yes. If you are publishing the work, then the legal code puts it clearly.
If You Distribute, or Publicly Perform the Work or any Adaptations or Collections, You must, unless a request has been made pursuant to Section 4(a), keep intact all copyright notices for the Work and provide, reasonable to the medium or means You are utilizing:
(i) the name of the Original Author (or pseudonym, if applicable) if supplied, and/or if the Original Author and/or Licensor designate another party or parties (e.g., a sponsor institute, publishing entity, journal) for attribution ("Attribution Parties") in Licensor's copyright notice, terms of service or by other reasonable means, the name of such party or parties;
(ii) the title of the Work if supplied;
(iii) to the extent reasonably practicable, the URI, if any, that Licensor specifies to be associated with the Work, unless such URI does not refer to the copyright notice or licensing information for the Work; and
(iv) , consistent with Section 3(b), in the case of an Adaptation, a credit identifying the use of the Work in the Adaptation (e.g., "French translation of the Work by Original Author," or "Screenplay based on original Work by Original Author").
So a statement satisfying all those would be "This product includes code from a tutorial by pointclouds.org, available here."