Paper check About

Point Set Surfaces

2001 · paper · Computer science

Advocates representing shapes as point sets and defines a smooth manifold surface from them using moving least squares. It gives tools to raise or lower point density and a point-rendering technique producing smooth shading and silhouettes at interactive frame rates.

Checked: PDF from sci.utah.edu, fetched 4 Oct 2026. Page numbers are those of that PDF.

3 findings

Reference or label Text: "applied on the set of red points depicted in (a). First, the red points are projected on the MLS surface to yield the blue points"; Figure 6 caption and panel (a) show green input points and orange projected points.
  • p. 5 Figure 6 caption
    Noisy input points (green points) are projected onto their smooth MLS curve (orange points).
  • p. 5 Down-sampling, paragraph on Figure 6
    First, the red points are projected on the MLS surface to yield the blue points.
  • p. 5 Decimation text
    First, the red points are projected on the
  • p. 5 Figure 6 caption
    Noisy input points (green points) are projected onto their

Judge's note: Looked at the full p.5 image. Panel (a) of Figure 6 shows green/yellow and orange points, with no red or blue. Red and blue appear only in panel (b), where they code error value. The colour names in the text do not match the figure or the caption.

Second check: another model agreed

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Wording Introduction states the surface is "guaranteed to be a 2-manifold and C∞ smooth", but Section 3.1 says Levin proves only the 2-manifold property and that infinite smoothness is a "conjecture".
  • p. 2 Section 1, 'Smooth manifold surface' property
    guaranteed to be a 2-manifold and C∞ smooth
  • p. 3 Section 3.1, end
    leads to the conjecture that the resulting surface is infinitely smooth
  • p. 3 Section 3.1
    leads to the conjecture that the

Only the authors can say what is right here.

Judge's note: Checked p.2 (Smooth manifold surface bullet) and p.3 Section 3.1 end: "Levin proves ... two-dimensional manifold [27]. Further, a general analysis of moving least squares [26] leads to the conjecture that the resulting surface is infinitely smooth as long as θ ∈ C∞". The introduction calls C∞ smoothness guaranteed, which is more than the body supports.

Second check: another model agreed

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Wording Conclusion: "We showed that the error of these approximations is bounded and dependent on the spacing among points", but no such bound is derived, stated or measured in the paper.
  • p. 7 Section 6 Conclusion, second paragraph
    We showed that the error of these approximations is bounded and dependent on the spacing among points.

Only the authors can say what is right here.

Judge's note: Searched the text for bound, error, tolerance, spacing and approximation order. Section 3 gives only qualitative remarks about h reflecting point spacing, and Section 5 says patches are "a good approximation". No error bound for the polynomial patches appears, and none is cited at that point. The authors may have meant Levin [26,27].

Second check: another model agreed

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13 minor (typos and the like; most checked by the judge only)
Reference or label Reference [30] (Lloyd, "Least squares quantization in PCM") gives the pages as "28:128–137, 1982"; the published first page is 129.
  • p. 8
    S. P. Lloyd. Least squares quantization in PCM. IEEE Transactions on Information Theory, 2

Only the authors can say what is right here.

Judge's note: Rests on outside knowledge: that Crossref (doi:10.1109/tit.1982.1056489) records pages 129–137 for this article. The page image confirms that ref [30] prints "28:128–137, 1982".

Second check: another model agreed, code check

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Wording Results: "The number of representation points ranges from 1000 (for the torus)", but the wavy torus depicted in Figure 7 originally has "800 points"; it is not stated which torus is meant.
  • p. 5 Figure 7 caption
    originally consisting of 800 points has been up-sampled to 20K points
  • p. 6 Up-sampling, last sentence
    the same object after adding 20K points over its MLS surface
  • p. 7 Results, last paragraph
    ranges from 1000 (for the torus)
  • p. 5 Figure 7 caption
    torus originally consisting of 800 points has been up-sampled to 20K points

Judge's note: Figure 10 caption (p.8) gives a torus mesh of "1000 vertices", which fits the Results value. The wavy torus in Figure 7 (p.5) and the p.6 text has 800 points, which is below the stated minimum for "all models depicted". The likely reading is that the 1000 refers to the Figure 10 torus, so this is an ambiguity, not an error. The 20K total-versus-added point is handled under C013.

Second check: another model agreed

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Wording Figure 7 caption: torus of 800 points "has been up-sampled to 20K points" (a total), while the p.6 text says "after adding 20K points over its MLS surface" (an increment).
  • p. 6 Up-sampling text
    after adding 20K points over its MLS surface
  • p. 5 Figure 7 caption
    has been up-sampled to 20K points
  • p. 5 Figure 7 caption
    up-sampled to 20K points

Judge's note: Both seen in the page images (p.5 caption, p.6 text). Adding 20K points gives about 20.8K, so the two phrasings describe different quantities. The difference is small and could be rounding or loose wording.

Second check: another model agreed

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Wording Section 5 says polynomials "are a good approximation to the surface inside a patch [−h, h]2 around a point", while the Figure 8 caption says "a square patch of [−h, h]2 would lead to unpleasant effects in some cases, as the polynomial might leave the ball of radius h".
  • p. 6 Sampling additional points, first paragraph
    are a good approximation to the surface inside a patch [−h, h]2 around a point
  • p. 6 Figure 8 caption
    a square patch of [−h, h]2 would lead to unpleasant effects in some cases

Judge's note: Both seen on the p.6 image. The two statements are in tension: the square's corners lie outside the radius-h ball. The text then defines the patch extent as the bounding box of the projected neighbours. Could be loose wording, but it is unresolved as printed.

Second check: another model agreed

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Typo Misspellings: "distance to a locally defined tangent plan" (plane) on p.2; in the references, "IEEE Transaltions on Pattern Analysis" [5] and "Geometric structues" [6].
  • p. 2 Section 2 Consolidation
    distance to a locally defined tangent plan
  • p. 4 Section 3.2
    main memroy of 512MB
  • p. 2 Related work
    locally defined tangent plan
  • p. 6 Sampling additional points
    displayed with the approach. pre-

Judge's note: Each was seen in the page images (p.2 right column; p.8 refs [5], [6]). The other items reviewers grouped here ('memroy', 'then', the stray full stop) are judged separately under C006, C009 and C012.

Second check: none (judge only)

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Typo "The volumetric sign-distance techniques described above" should read "signed-distance", the term used in the preceding paragraph.
  • p. 2 Section 2 Consolidation
    The volumetric sign-distance techniques

Judge's note: Seen in the p.2 image. The previous paragraph says "signed distance" twice.

Second check: none (judge only)

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Typo "the available main memroy of 512MB" should read "memory".
  • p. 4 Section 3.2, last paragraph
    main memroy of 512MB
  • p. 4
    available main memroy of 512MB

Judge's note: Seen in the p.4 image, end of Section 3.2.

Second check: none (judge only)

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Typo "where the spacing among points is larger then a specified bound" should read "than".
  • p. 5 Up-sampling, first paragraph
    larger then a specified bound
  • p. 5 Up-sampling
    is larger then a specified bound

Judge's note: Seen in the p.5 image, Up-sampling paragraph.

Second check: none (judge only)

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Typo Stray full stop: "can be readily displayed with the approach. presented here."
  • p. 6 Sampling additional points
    with the approach. pre-
  • p. 6 Sampling additional points
    displayed with the approach. pre-
  • p. 6
    displayed with the approach. pre-sented here

Judge's note: Seen in the p.6 image, Sampling additional points paragraph.

Second check: none (judge only)

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Typo "An example of a environment mapping" should read "an environment mapping".
  • p. 7 Results paragraph
    An example of a environment mapping

Judge's note: Seen in the p.7 image, Results paragraph.

Second check: none (judge only)

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Typo Reference [5] misspells the journal name: "IEEE Transaltions on Pattern Analysis and Machine Intelligence" should read "Transactions".
  • p. 8 Reference [5]
    Transaltions on Pattern Analysis and Machine Intelligence
  • p. 8 Ref [5]
    Transaltions on Pattern Analysis
  • p. 8 Ref [6]
    Geometric structues for
  • p. 8 Ref [32]
    Spatial Tesselations

Judge's note: The page image shows "Transaltions" in ref [5] on p. 8. The cluster also lists the [6] 'structues' and [32] 'Tesselations' quotes, but those are judged separately under C017 and C018. This verdict covers only the [5] misspelling.

Second check: none (judge only)

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Typo Reference [6] misspells a word in the title: "Geometric structues for three-dimensional shape representation" should read "structures".
  • p. 8 Reference [6]
    Geometric structues for three-dimensional shape representa-

Judge's note: The page image shows "structues" in the title of ref [6] (Boissonnat) on p. 8.

Second check: none (judge only)

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Typo Reference [32] gives the book title as "Spatial Tesselations — Concepts and Applications of Voronoi Diagrams"; the book's published title spells it "Tessellations".
  • p. 8 Reference [32]
    Spatial Tesselations

Only the authors can say what is right here.

Judge's note: Rests on outside knowledge: that the Okabe/Boots/Sugihara book (Wiley 1992) is titled 'Spatial Tessellations'. The page image confirms the printed text reads "Tesselations". 'Tesselation' is a variant spelling, so this is minor.

Second check: none (judge only)

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